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fs/namei.c
111 KB
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/* * linux/fs/namei.c * * Copyright (C) 1991, 1992 Linus Torvalds */ /* * Some corrections by tytso. */ /* [Feb 1997 T. Schoebel-Theuer] Complete rewrite of the pathname * lookup logic. */ /* [Feb-Apr 2000, AV] Rewrite to the new namespace architecture. */ #include <linux/init.h> |
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#include <linux/export.h> |
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#include <linux/kernel.h> |
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#include <linux/slab.h> #include <linux/fs.h> #include <linux/namei.h> |
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#include <linux/pagemap.h> |
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#include <linux/fsnotify.h> |
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#include <linux/personality.h> #include <linux/security.h> |
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#include <linux/ima.h> |
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#include <linux/syscalls.h> #include <linux/mount.h> #include <linux/audit.h> |
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#include <linux/capability.h> |
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#include <linux/file.h> |
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#include <linux/fcntl.h> |
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#include <linux/device_cgroup.h> |
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#include <linux/fs_struct.h> |
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#include <linux/posix_acl.h> |
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#include <asm/uaccess.h> |
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#include "internal.h" |
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#include "mount.h" |
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|
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/* [Feb-1997 T. Schoebel-Theuer] * Fundamental changes in the pathname lookup mechanisms (namei) * were necessary because of omirr. The reason is that omirr needs * to know the _real_ pathname, not the user-supplied one, in case * of symlinks (and also when transname replacements occur). * * The new code replaces the old recursive symlink resolution with * an iterative one (in case of non-nested symlink chains). It does * this with calls to <fs>_follow_link(). * As a side effect, dir_namei(), _namei() and follow_link() are now * replaced with a single function lookup_dentry() that can handle all * the special cases of the former code. * * With the new dcache, the pathname is stored at each inode, at least as * long as the refcount of the inode is positive. As a side effect, the * size of the dcache depends on the inode cache and thus is dynamic. * * [29-Apr-1998 C. Scott Ananian] Updated above description of symlink * resolution to correspond with current state of the code. * * Note that the symlink resolution is not *completely* iterative. * There is still a significant amount of tail- and mid- recursion in * the algorithm. Also, note that <fs>_readlink() is not used in * lookup_dentry(): lookup_dentry() on the result of <fs>_readlink() * may return different results than <fs>_follow_link(). Many virtual * filesystems (including /proc) exhibit this behavior. */ /* [24-Feb-97 T. Schoebel-Theuer] Side effects caused by new implementation: * New symlink semantics: when open() is called with flags O_CREAT | O_EXCL * and the name already exists in form of a symlink, try to create the new * name indicated by the symlink. The old code always complained that the * name already exists, due to not following the symlink even if its target * is nonexistent. The new semantics affects also mknod() and link() when |
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* the name is a symlink pointing to a non-existent name. |
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* * I don't know which semantics is the right one, since I have no access * to standards. But I found by trial that HP-UX 9.0 has the full "new" * semantics implemented, while SunOS 4.1.1 and Solaris (SunOS 5.4) have the * "old" one. Personally, I think the new semantics is much more logical. * Note that "ln old new" where "new" is a symlink pointing to a non-existing * file does succeed in both HP-UX and SunOs, but not in Solaris * and in the old Linux semantics. */ /* [16-Dec-97 Kevin Buhr] For security reasons, we change some symlink * semantics. See the comments in "open_namei" and "do_link" below. * * [10-Sep-98 Alan Modra] Another symlink change. */ /* [Feb-Apr 2000 AV] Complete rewrite. Rules for symlinks: * inside the path - always follow. * in the last component in creation/removal/renaming - never follow. * if LOOKUP_FOLLOW passed - follow. * if the pathname has trailing slashes - follow. * otherwise - don't follow. * (applied in that order). * * [Jun 2000 AV] Inconsistent behaviour of open() in case if flags==O_CREAT * restored for 2.4. This is the last surviving part of old 4.2BSD bug. * During the 2.4 we need to fix the userland stuff depending on it - * hopefully we will be able to get rid of that wart in 2.5. So far only * XEmacs seems to be relying on it... */ /* * [Sep 2001 AV] Single-semaphore locking scheme (kudos to David Holland) |
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* implemented. Let's see if raised priority of ->s_vfs_rename_mutex gives |
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* any extra contention... */ /* In order to reduce some races, while at the same time doing additional * checking and hopefully speeding things up, we copy filenames to the * kernel data space before using them.. * * POSIX.1 2.4: an empty pathname is invalid (ENOENT). * PATH_MAX includes the nul terminator --RR. */ |
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void final_putname(struct filename *name) |
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{ |
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if (name->separate) { __putname(name->name); kfree(name); } else { __putname(name); } |
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} |
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#define EMBEDDED_NAME_MAX (PATH_MAX - sizeof(struct filename)) |
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static struct filename * getname_flags(const char __user *filename, int flags, int *empty) { struct filename *result, *err; |
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int len; |
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long max; char *kname; |
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|
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result = audit_reusename(filename); if (result) return result; |
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result = __getname(); |
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if (unlikely(!result)) |
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return ERR_PTR(-ENOMEM); |
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/* * First, try to embed the struct filename inside the names_cache * allocation */ kname = (char *)result + sizeof(*result); |
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result->name = kname; |
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result->separate = false; max = EMBEDDED_NAME_MAX; recopy: len = strncpy_from_user(kname, filename, max); |
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if (unlikely(len < 0)) { err = ERR_PTR(len); |
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goto error; |
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} |
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|
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/* * Uh-oh. We have a name that's approaching PATH_MAX. Allocate a * separate struct filename so we can dedicate the entire * names_cache allocation for the pathname, and re-do the copy from * userland. */ if (len == EMBEDDED_NAME_MAX && max == EMBEDDED_NAME_MAX) { kname = (char *)result; result = kzalloc(sizeof(*result), GFP_KERNEL); if (!result) { err = ERR_PTR(-ENOMEM); result = (struct filename *)kname; goto error; } result->name = kname; result->separate = true; max = PATH_MAX; goto recopy; } |
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/* The empty path is special. */ if (unlikely(!len)) { if (empty) |
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*empty = 1; |
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err = ERR_PTR(-ENOENT); if (!(flags & LOOKUP_EMPTY)) goto error; |
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} |
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err = ERR_PTR(-ENAMETOOLONG); |
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if (unlikely(len >= PATH_MAX)) goto error; result->uptr = filename; |
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result->aname = NULL; |
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audit_getname(result); return result; |
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error: |
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final_putname(result); |
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return err; |
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} |
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struct filename * getname(const char __user * filename) |
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{ |
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return getname_flags(filename, 0, NULL); |
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} |
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/* * The "getname_kernel()" interface doesn't do pathnames longer * than EMBEDDED_NAME_MAX. Deal with it - you're a kernel user. */ struct filename * getname_kernel(const char * filename) { struct filename *result; char *kname; int len; len = strlen(filename); if (len >= EMBEDDED_NAME_MAX) return ERR_PTR(-ENAMETOOLONG); result = __getname(); if (unlikely(!result)) return ERR_PTR(-ENOMEM); kname = (char *)result + sizeof(*result); result->name = kname; result->uptr = NULL; result->aname = NULL; result->separate = false; strlcpy(kname, filename, EMBEDDED_NAME_MAX); return result; } |
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#ifdef CONFIG_AUDITSYSCALL |
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void putname(struct filename *name) |
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{ |
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if (unlikely(!audit_dummy_context())) |
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return audit_putname(name); final_putname(name); |
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} |
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#endif |
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static int check_acl(struct inode *inode, int mask) { |
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#ifdef CONFIG_FS_POSIX_ACL |
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struct posix_acl *acl; |
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if (mask & MAY_NOT_BLOCK) { |
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acl = get_cached_acl_rcu(inode, ACL_TYPE_ACCESS); if (!acl) |
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return -EAGAIN; |
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/* no ->get_acl() calls in RCU mode... */ if (acl == ACL_NOT_CACHED) return -ECHILD; |
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return posix_acl_permission(inode, acl, mask & ~MAY_NOT_BLOCK); |
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} |
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acl = get_acl(inode, ACL_TYPE_ACCESS); if (IS_ERR(acl)) return PTR_ERR(acl); |
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if (acl) { int error = posix_acl_permission(inode, acl, mask); posix_acl_release(acl); return error; } |
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#endif |
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return -EAGAIN; } |
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/* |
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* This does the basic permission checking |
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*/ |
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static int acl_permission_check(struct inode *inode, int mask) |
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{ |
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unsigned int mode = inode->i_mode; |
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|
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if (likely(uid_eq(current_fsuid(), inode->i_uid))) |
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mode >>= 6; else { |
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if (IS_POSIXACL(inode) && (mode & S_IRWXG)) { |
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int error = check_acl(inode, mask); |
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if (error != -EAGAIN) return error; |
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} if (in_group_p(inode->i_gid)) mode >>= 3; } /* * If the DACs are ok we don't need any capability check. */ |
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if ((mask & ~mode & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0) |
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return 0; |
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return -EACCES; } /** |
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* generic_permission - check for access rights on a Posix-like filesystem |
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* @inode: inode to check access rights for |
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* @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC, ...) |
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* * Used to check for read/write/execute permissions on a file. * We use "fsuid" for this, letting us set arbitrary permissions * for filesystem access without changing the "normal" uids which |
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* are used for other things. * * generic_permission is rcu-walk aware. It returns -ECHILD in case an rcu-walk * request cannot be satisfied (eg. requires blocking or too much complexity). * It would then be called again in ref-walk mode. |
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*/ |
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int generic_permission(struct inode *inode, int mask) |
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{ int ret; /* |
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* Do the basic permission checks. |
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*/ |
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ret = acl_permission_check(inode, mask); |
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if (ret != -EACCES) return ret; |
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|
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if (S_ISDIR(inode->i_mode)) { /* DACs are overridable for directories */ |
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if (capable_wrt_inode_uidgid(inode, CAP_DAC_OVERRIDE)) |
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return 0; if (!(mask & MAY_WRITE)) |
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if (capable_wrt_inode_uidgid(inode, CAP_DAC_READ_SEARCH)) |
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return 0; return -EACCES; } |
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/* * Read/write DACs are always overridable. |
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* Executable DACs are overridable when there is * at least one exec bit set. |
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*/ |
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if (!(mask & MAY_EXEC) || (inode->i_mode & S_IXUGO)) |
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if (capable_wrt_inode_uidgid(inode, CAP_DAC_OVERRIDE)) |
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return 0; /* * Searching includes executable on directories, else just read. */ |
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mask &= MAY_READ | MAY_WRITE | MAY_EXEC; |
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if (mask == MAY_READ) |
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if (capable_wrt_inode_uidgid(inode, CAP_DAC_READ_SEARCH)) |
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return 0; return -EACCES; } |
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EXPORT_SYMBOL(generic_permission); |
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|
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/* * We _really_ want to just do "generic_permission()" without * even looking at the inode->i_op values. So we keep a cache * flag in inode->i_opflags, that says "this has not special * permission function, use the fast case". */ static inline int do_inode_permission(struct inode *inode, int mask) { if (unlikely(!(inode->i_opflags & IOP_FASTPERM))) { if (likely(inode->i_op->permission)) return inode->i_op->permission(inode, mask); /* This gets set once for the inode lifetime */ spin_lock(&inode->i_lock); inode->i_opflags |= IOP_FASTPERM; spin_unlock(&inode->i_lock); } return generic_permission(inode, mask); } |
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/** |
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* __inode_permission - Check for access rights to a given inode * @inode: Inode to check permission on * @mask: Right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC) |
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* |
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* Check for read/write/execute permissions on an inode. |
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* * When checking for MAY_APPEND, MAY_WRITE must also be set in @mask. |
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* * This does not check for a read-only file system. You probably want * inode_permission(). |
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*/ |
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int __inode_permission(struct inode *inode, int mask) |
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{ |
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int retval; |
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|
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if (unlikely(mask & MAY_WRITE)) { |
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/* * Nobody gets write access to an immutable file. */ if (IS_IMMUTABLE(inode)) return -EACCES; } |
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retval = do_inode_permission(inode, mask); |
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if (retval) return retval; |
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retval = devcgroup_inode_permission(inode, mask); if (retval) return retval; |
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return security_inode_permission(inode, mask); |
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} |
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/** |
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* sb_permission - Check superblock-level permissions * @sb: Superblock of inode to check permission on |
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* @inode: Inode to check permission on |
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* @mask: Right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC) * * Separate out file-system wide checks from inode-specific permission checks. */ static int sb_permission(struct super_block *sb, struct inode *inode, int mask) { if (unlikely(mask & MAY_WRITE)) { umode_t mode = inode->i_mode; /* Nobody gets write access to a read-only fs. */ if ((sb->s_flags & MS_RDONLY) && (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) return -EROFS; } return 0; } /** * inode_permission - Check for access rights to a given inode * @inode: Inode to check permission on * @mask: Right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC) * * Check for read/write/execute permissions on an inode. We use fs[ug]id for * this, letting us set arbitrary permissions for filesystem access without * changing the "normal" UIDs which are used for other things. * * When checking for MAY_APPEND, MAY_WRITE must also be set in @mask. */ int inode_permission(struct inode *inode, int mask) { int retval; retval = sb_permission(inode->i_sb, inode, mask); if (retval) return retval; return __inode_permission(inode, mask); } |
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EXPORT_SYMBOL(inode_permission); |
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/** |
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* path_get - get a reference to a path * @path: path to get the reference to * * Given a path increment the reference count to the dentry and the vfsmount. */ |
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void path_get(const struct path *path) |
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{ mntget(path->mnt); dget(path->dentry); } EXPORT_SYMBOL(path_get); /** |
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* path_put - put a reference to a path * @path: path to put the reference to * * Given a path decrement the reference count to the dentry and the vfsmount. */ |
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void path_put(const struct path *path) |
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{ |
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dput(path->dentry); mntput(path->mnt); |
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} |
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EXPORT_SYMBOL(path_put); |
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|
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/* |
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* Path walking has 2 modes, rcu-walk and ref-walk (see |
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* Documentation/filesystems/path-lookup.txt). In situations when we can't * continue in RCU mode, we attempt to drop out of rcu-walk mode and grab * normal reference counts on dentries and vfsmounts to transition to rcu-walk * mode. Refcounts are grabbed at the last known good point before rcu-walk * got stuck, so ref-walk may continue from there. If this is not successful * (eg. a seqcount has changed), then failure is returned and it's up to caller * to restart the path walk from the beginning in ref-walk mode. |
31e6b01f4 fs: rcu-walk for ... |
479 |
*/ |
31e6b01f4 fs: rcu-walk for ... |
480 481 |
/** |
19660af73 consolidate namei... |
482 483 484 |
* unlazy_walk - try to switch to ref-walk mode. * @nd: nameidata pathwalk data * @dentry: child of nd->path.dentry or NULL |
39191628e fs: fix namei.c k... |
485 |
* Returns: 0 on success, -ECHILD on failure |
31e6b01f4 fs: rcu-walk for ... |
486 |
* |
19660af73 consolidate namei... |
487 488 489 |
* unlazy_walk attempts to legitimize the current nd->path, nd->root and dentry * for ref-walk mode. @dentry must be a path found by a do_lookup call on * @nd or NULL. Must be called from rcu-walk context. |
31e6b01f4 fs: rcu-walk for ... |
490 |
*/ |
19660af73 consolidate namei... |
491 |
static int unlazy_walk(struct nameidata *nd, struct dentry *dentry) |
31e6b01f4 fs: rcu-walk for ... |
492 493 494 495 496 |
{ struct fs_struct *fs = current->fs; struct dentry *parent = nd->path.dentry; BUG_ON(!(nd->flags & LOOKUP_RCU)); |
e5c832d55 vfs: fix dentry R... |
497 498 |
/* |
48a066e72 RCU'd vfsmounts |
499 500 501 502 503 504 |
* After legitimizing the bastards, terminate_walk() * will do the right thing for non-RCU mode, and all our * subsequent exit cases should rcu_read_unlock() * before returning. Do vfsmount first; if dentry * can't be legitimized, just set nd->path.dentry to NULL * and rely on dput(NULL) being a no-op. |
e5c832d55 vfs: fix dentry R... |
505 |
*/ |
48a066e72 RCU'd vfsmounts |
506 |
if (!legitimize_mnt(nd->path.mnt, nd->m_seq)) |
e5c832d55 vfs: fix dentry R... |
507 |
return -ECHILD; |
e5c832d55 vfs: fix dentry R... |
508 |
nd->flags &= ~LOOKUP_RCU; |
15570086b vfs: reimplement ... |
509 |
|
48a066e72 RCU'd vfsmounts |
510 511 |
if (!lockref_get_not_dead(&parent->d_lockref)) { nd->path.dentry = NULL; |
d870b4a19 fix bogus path_pu... |
512 |
goto out; |
48a066e72 RCU'd vfsmounts |
513 |
} |
15570086b vfs: reimplement ... |
514 515 516 517 518 519 520 521 522 523 524 |
/* * For a negative lookup, the lookup sequence point is the parents * sequence point, and it only needs to revalidate the parent dentry. * * For a positive lookup, we need to move both the parent and the * dentry from the RCU domain to be properly refcounted. And the * sequence number in the dentry validates *both* dentry counters, * since we checked the sequence number of the parent after we got * the child sequence number. So we know the parent must still * be valid if the child sequence number is still valid. */ |
19660af73 consolidate namei... |
525 |
if (!dentry) { |
e5c832d55 vfs: fix dentry R... |
526 527 |
if (read_seqcount_retry(&parent->d_seq, nd->seq)) goto out; |
19660af73 consolidate namei... |
528 529 |
BUG_ON(nd->inode != parent->d_inode); } else { |
e5c832d55 vfs: fix dentry R... |
530 531 532 533 |
if (!lockref_get_not_dead(&dentry->d_lockref)) goto out; if (read_seqcount_retry(&dentry->d_seq, nd->seq)) goto drop_dentry; |
19660af73 consolidate namei... |
534 |
} |
e5c832d55 vfs: fix dentry R... |
535 536 537 538 539 540 541 542 543 |
/* * Sequence counts matched. Now make sure that the root is * still valid and get it if required. */ if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) { spin_lock(&fs->lock); if (nd->root.mnt != fs->root.mnt || nd->root.dentry != fs->root.dentry) goto unlock_and_drop_dentry; |
31e6b01f4 fs: rcu-walk for ... |
544 545 546 |
path_get(&nd->root); spin_unlock(&fs->lock); } |
31e6b01f4 fs: rcu-walk for ... |
547 |
|
8b61e74ff get rid of {lock,... |
548 |
rcu_read_unlock(); |
31e6b01f4 fs: rcu-walk for ... |
549 |
return 0; |
19660af73 consolidate namei... |
550 |
|
e5c832d55 vfs: fix dentry R... |
551 552 553 |
unlock_and_drop_dentry: spin_unlock(&fs->lock); drop_dentry: |
8b61e74ff get rid of {lock,... |
554 |
rcu_read_unlock(); |
15570086b vfs: reimplement ... |
555 |
dput(dentry); |
d0d272771 vfs: make sure we... |
556 |
goto drop_root_mnt; |
e5c832d55 vfs: fix dentry R... |
557 |
out: |
8b61e74ff get rid of {lock,... |
558 |
rcu_read_unlock(); |
d0d272771 vfs: make sure we... |
559 560 561 |
drop_root_mnt: if (!(nd->flags & LOOKUP_ROOT)) nd->root.mnt = NULL; |
31e6b01f4 fs: rcu-walk for ... |
562 563 |
return -ECHILD; } |
4ce16ef3f fs/namei.c: don't... |
564 |
static inline int d_revalidate(struct dentry *dentry, unsigned int flags) |
34286d666 fs: rcu-walk awar... |
565 |
{ |
4ce16ef3f fs/namei.c: don't... |
566 |
return dentry->d_op->d_revalidate(dentry, flags); |
34286d666 fs: rcu-walk awar... |
567 |
} |
9f1fafee9 merge handle_reva... |
568 569 570 |
/** * complete_walk - successful completion of path walk * @nd: pointer nameidata |
39159de2a vfs: force reval ... |
571 |
* |
9f1fafee9 merge handle_reva... |
572 573 574 575 576 |
* If we had been in RCU mode, drop out of it and legitimize nd->path. * Revalidate the final result, unless we'd already done that during * the path walk or the filesystem doesn't ask for it. Return 0 on * success, -error on failure. In case of failure caller does not * need to drop nd->path. |
39159de2a vfs: force reval ... |
577 |
*/ |
9f1fafee9 merge handle_reva... |
578 |
static int complete_walk(struct nameidata *nd) |
39159de2a vfs: force reval ... |
579 |
{ |
16c2cd717 untangle the "nee... |
580 |
struct dentry *dentry = nd->path.dentry; |
39159de2a vfs: force reval ... |
581 |
int status; |
39159de2a vfs: force reval ... |
582 |
|
9f1fafee9 merge handle_reva... |
583 584 585 586 |
if (nd->flags & LOOKUP_RCU) { nd->flags &= ~LOOKUP_RCU; if (!(nd->flags & LOOKUP_ROOT)) nd->root.mnt = NULL; |
15570086b vfs: reimplement ... |
587 |
|
48a066e72 RCU'd vfsmounts |
588 |
if (!legitimize_mnt(nd->path.mnt, nd->m_seq)) { |
8b61e74ff get rid of {lock,... |
589 |
rcu_read_unlock(); |
48a066e72 RCU'd vfsmounts |
590 591 |
return -ECHILD; } |
e5c832d55 vfs: fix dentry R... |
592 |
if (unlikely(!lockref_get_not_dead(&dentry->d_lockref))) { |
8b61e74ff get rid of {lock,... |
593 |
rcu_read_unlock(); |
48a066e72 RCU'd vfsmounts |
594 |
mntput(nd->path.mnt); |
e5c832d55 vfs: fix dentry R... |
595 596 597 |
return -ECHILD; } if (read_seqcount_retry(&dentry->d_seq, nd->seq)) { |
8b61e74ff get rid of {lock,... |
598 |
rcu_read_unlock(); |
e5c832d55 vfs: fix dentry R... |
599 |
dput(dentry); |
48a066e72 RCU'd vfsmounts |
600 |
mntput(nd->path.mnt); |
9f1fafee9 merge handle_reva... |
601 602 |
return -ECHILD; } |
8b61e74ff get rid of {lock,... |
603 |
rcu_read_unlock(); |
9f1fafee9 merge handle_reva... |
604 |
} |
16c2cd717 untangle the "nee... |
605 606 |
if (likely(!(nd->flags & LOOKUP_JUMPED))) return 0; |
ecf3d1f1a vfs: kill FS_REVA... |
607 |
if (likely(!(dentry->d_flags & DCACHE_OP_WEAK_REVALIDATE))) |
39159de2a vfs: force reval ... |
608 |
return 0; |
ecf3d1f1a vfs: kill FS_REVA... |
609 |
status = dentry->d_op->d_weak_revalidate(dentry, nd->flags); |
39159de2a vfs: force reval ... |
610 611 |
if (status > 0) return 0; |
16c2cd717 untangle the "nee... |
612 |
if (!status) |
39159de2a vfs: force reval ... |
613 |
status = -ESTALE; |
16c2cd717 untangle the "nee... |
614 |
|
9f1fafee9 merge handle_reva... |
615 |
path_put(&nd->path); |
39159de2a vfs: force reval ... |
616 617 |
return status; } |
2a7378711 Cache root in nam... |
618 619 |
static __always_inline void set_root(struct nameidata *nd) { |
f7ad3c6be vfs: add helpers ... |
620 621 |
if (!nd->root.mnt) get_fs_root(current->fs, &nd->root); |
2a7378711 Cache root in nam... |
622 |
} |
6de88d729 kill __link_path_... |
623 |
static int link_path_walk(const char *, struct nameidata *); |
31e6b01f4 fs: rcu-walk for ... |
624 625 626 627 |
static __always_inline void set_root_rcu(struct nameidata *nd) { if (!nd->root.mnt) { struct fs_struct *fs = current->fs; |
c28cc3646 fs: fs_struct use... |
628 629 630 631 632 |
unsigned seq; do { seq = read_seqcount_begin(&fs->seq); nd->root = fs->root; |
c1530019e vfs: Fix absolute... |
633 |
nd->seq = __read_seqcount_begin(&nd->root.dentry->d_seq); |
c28cc3646 fs: fs_struct use... |
634 |
} while (read_seqcount_retry(&fs->seq, seq)); |
31e6b01f4 fs: rcu-walk for ... |
635 636 |
} } |
1d957f9bf Introduce path_put() |
637 |
static void path_put_conditional(struct path *path, struct nameidata *nd) |
051d38125 [PATCH] autofs4: ... |
638 639 |
{ dput(path->dentry); |
4ac913785 Embed a struct pa... |
640 |
if (path->mnt != nd->path.mnt) |
051d38125 [PATCH] autofs4: ... |
641 642 |
mntput(path->mnt); } |
7b9337aaf fs: namei fix ->p... |
643 644 |
static inline void path_to_nameidata(const struct path *path, struct nameidata *nd) |
051d38125 [PATCH] autofs4: ... |
645 |
{ |
31e6b01f4 fs: rcu-walk for ... |
646 647 648 649 |
if (!(nd->flags & LOOKUP_RCU)) { dput(nd->path.dentry); if (nd->path.mnt != path->mnt) mntput(nd->path.mnt); |
9a2296832 namei.c : update ... |
650 |
} |
31e6b01f4 fs: rcu-walk for ... |
651 |
nd->path.mnt = path->mnt; |
4ac913785 Embed a struct pa... |
652 |
nd->path.dentry = path->dentry; |
051d38125 [PATCH] autofs4: ... |
653 |
} |
b5fb63c18 fs: add nd_jump_link |
654 655 656 657 658 659 660 661 662 663 664 |
/* * Helper to directly jump to a known parsed path from ->follow_link, * caller must have taken a reference to path beforehand. */ void nd_jump_link(struct nameidata *nd, struct path *path) { path_put(&nd->path); nd->path = *path; nd->inode = nd->path.dentry->d_inode; nd->flags |= LOOKUP_JUMPED; |
b5fb63c18 fs: add nd_jump_link |
665 |
} |
574197e0d tidy the trailing... |
666 667 668 |
static inline void put_link(struct nameidata *nd, struct path *link, void *cookie) { struct inode *inode = link->dentry->d_inode; |
6d7b5aaed namei.c: let foll... |
669 |
if (inode->i_op->put_link) |
574197e0d tidy the trailing... |
670 671 672 |
inode->i_op->put_link(link->dentry, nd, cookie); path_put(link); } |
561ec64ae VFS: don't do pro... |
673 674 |
int sysctl_protected_symlinks __read_mostly = 0; int sysctl_protected_hardlinks __read_mostly = 0; |
800179c9b fs: add link rest... |
675 676 677 678 |
/** * may_follow_link - Check symlink following for unsafe situations * @link: The path of the symlink |
55852635a fs: fix fs/namei.... |
679 |
* @nd: nameidata pathwalk data |
800179c9b fs: add link rest... |
680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 |
* * In the case of the sysctl_protected_symlinks sysctl being enabled, * CAP_DAC_OVERRIDE needs to be specifically ignored if the symlink is * in a sticky world-writable directory. This is to protect privileged * processes from failing races against path names that may change out * from under them by way of other users creating malicious symlinks. * It will permit symlinks to be followed only when outside a sticky * world-writable directory, or when the uid of the symlink and follower * match, or when the directory owner matches the symlink's owner. * * Returns 0 if following the symlink is allowed, -ve on error. */ static inline int may_follow_link(struct path *link, struct nameidata *nd) { const struct inode *inode; const struct inode *parent; if (!sysctl_protected_symlinks) return 0; /* Allowed if owner and follower match. */ inode = link->dentry->d_inode; |
81abe27b1 userns: Fix link... |
702 |
if (uid_eq(current_cred()->fsuid, inode->i_uid)) |
800179c9b fs: add link rest... |
703 704 705 706 707 708 709 710 |
return 0; /* Allowed if parent directory not sticky and world-writable. */ parent = nd->path.dentry->d_inode; if ((parent->i_mode & (S_ISVTX|S_IWOTH)) != (S_ISVTX|S_IWOTH)) return 0; /* Allowed if parent directory and link owner match. */ |
81abe27b1 userns: Fix link... |
711 |
if (uid_eq(parent->i_uid, inode->i_uid)) |
800179c9b fs: add link rest... |
712 |
return 0; |
ffd8d101a fs: prevent use a... |
713 |
audit_log_link_denied("follow_link", link); |
800179c9b fs: add link rest... |
714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 |
path_put_conditional(link, nd); path_put(&nd->path); return -EACCES; } /** * safe_hardlink_source - Check for safe hardlink conditions * @inode: the source inode to hardlink from * * Return false if at least one of the following conditions: * - inode is not a regular file * - inode is setuid * - inode is setgid and group-exec * - access failure for read and write * * Otherwise returns true. */ static bool safe_hardlink_source(struct inode *inode) { umode_t mode = inode->i_mode; /* Special files should not get pinned to the filesystem. */ if (!S_ISREG(mode)) return false; /* Setuid files should not get pinned to the filesystem. */ if (mode & S_ISUID) return false; /* Executable setgid files should not get pinned to the filesystem. */ if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) return false; /* Hardlinking to unreadable or unwritable sources is dangerous. */ if (inode_permission(inode, MAY_READ | MAY_WRITE)) return false; return true; } /** * may_linkat - Check permissions for creating a hardlink * @link: the source to hardlink from * * Block hardlink when all of: * - sysctl_protected_hardlinks enabled * - fsuid does not match inode * - hardlink source is unsafe (see safe_hardlink_source() above) * - not CAP_FOWNER * * Returns 0 if successful, -ve on error. */ static int may_linkat(struct path *link) { const struct cred *cred; struct inode *inode; if (!sysctl_protected_hardlinks) return 0; cred = current_cred(); inode = link->dentry->d_inode; /* Source inode owner (or CAP_FOWNER) can hardlink all they like, * otherwise, it must be a safe source. */ |
81abe27b1 userns: Fix link... |
780 |
if (uid_eq(cred->fsuid, inode->i_uid) || safe_hardlink_source(inode) || |
800179c9b fs: add link rest... |
781 782 |
capable(CAP_FOWNER)) return 0; |
a51d9eaa4 fs: add link rest... |
783 |
audit_log_link_denied("linkat", link); |
800179c9b fs: add link rest... |
784 785 |
return -EPERM; } |
def4af30c Get rid of symlin... |
786 |
static __always_inline int |
574197e0d tidy the trailing... |
787 |
follow_link(struct path *link, struct nameidata *nd, void **p) |
1da177e4c Linux-2.6.12-rc2 |
788 |
{ |
7b9337aaf fs: namei fix ->p... |
789 |
struct dentry *dentry = link->dentry; |
6d7b5aaed namei.c: let foll... |
790 791 |
int error; char *s; |
1da177e4c Linux-2.6.12-rc2 |
792 |
|
844a39179 nothing in do_fol... |
793 |
BUG_ON(nd->flags & LOOKUP_RCU); |
0e794589e fix follow_link()... |
794 795 |
if (link->mnt == nd->path.mnt) mntget(link->mnt); |
6d7b5aaed namei.c: let foll... |
796 797 798 |
error = -ELOOP; if (unlikely(current->total_link_count >= 40)) goto out_put_nd_path; |
574197e0d tidy the trailing... |
799 800 |
cond_resched(); current->total_link_count++; |
68ac1234f switch touch_atim... |
801 |
touch_atime(link); |
1da177e4c Linux-2.6.12-rc2 |
802 |
nd_set_link(nd, NULL); |
cd4e91d3b [PATCH] namei fix... |
803 |
|
36f3b4f69 pull security_ino... |
804 |
error = security_inode_follow_link(link->dentry, nd); |
6d7b5aaed namei.c: let foll... |
805 806 |
if (error) goto out_put_nd_path; |
36f3b4f69 pull security_ino... |
807 |
|
86acdca1b fix autofs/afs/et... |
808 |
nd->last_type = LAST_BIND; |
def4af30c Get rid of symlin... |
809 810 |
*p = dentry->d_inode->i_op->follow_link(dentry, nd); error = PTR_ERR(*p); |
6d7b5aaed namei.c: let foll... |
811 |
if (IS_ERR(*p)) |
408ef013c fs: move path_put... |
812 |
goto out_put_nd_path; |
6d7b5aaed namei.c: let foll... |
813 814 815 816 |
error = 0; s = nd_get_link(nd); if (s) { |
443ed254c ... and fold the ... |
817 818 819 820 821 822 823 824 825 826 827 828 829 830 |
if (unlikely(IS_ERR(s))) { path_put(&nd->path); put_link(nd, link, *p); return PTR_ERR(s); } if (*s == '/') { set_root(nd); path_put(&nd->path); nd->path = nd->root; path_get(&nd->root); nd->flags |= LOOKUP_JUMPED; } nd->inode = nd->path.dentry->d_inode; error = link_path_walk(s, nd); |
b5fb63c18 fs: add nd_jump_link |
831 832 |
if (unlikely(error)) put_link(nd, link, *p); |
1da177e4c Linux-2.6.12-rc2 |
833 |
} |
6d7b5aaed namei.c: let foll... |
834 835 836 837 |
return error; out_put_nd_path: |
98f6ef64b vfs: bogus warnin... |
838 |
*p = NULL; |
6d7b5aaed namei.c: let foll... |
839 |
path_put(&nd->path); |
6d7b5aaed namei.c: let foll... |
840 |
path_put(link); |
1da177e4c Linux-2.6.12-rc2 |
841 842 |
return error; } |
31e6b01f4 fs: rcu-walk for ... |
843 844 |
static int follow_up_rcu(struct path *path) { |
0714a5338 vfs: now it can b... |
845 846 |
struct mount *mnt = real_mount(path->mnt); struct mount *parent; |
31e6b01f4 fs: rcu-walk for ... |
847 |
struct dentry *mountpoint; |
0714a5338 vfs: now it can b... |
848 849 |
parent = mnt->mnt_parent; if (&parent->mnt == path->mnt) |
31e6b01f4 fs: rcu-walk for ... |
850 |
return 0; |
a73324da7 vfs: move mnt_mou... |
851 |
mountpoint = mnt->mnt_mountpoint; |
31e6b01f4 fs: rcu-walk for ... |
852 |
path->dentry = mountpoint; |
0714a5338 vfs: now it can b... |
853 |
path->mnt = &parent->mnt; |
31e6b01f4 fs: rcu-walk for ... |
854 855 |
return 1; } |
f015f1267 VFS: Comment moun... |
856 857 858 859 860 861 862 863 864 865 |
/* * follow_up - Find the mountpoint of path's vfsmount * * Given a path, find the mountpoint of its source file system. * Replace @path with the path of the mountpoint in the parent mount. * Up is towards /. * * Return 1 if we went up a level and 0 if we were already at the * root. */ |
bab77ebf5 switch follow_up(... |
866 |
int follow_up(struct path *path) |
1da177e4c Linux-2.6.12-rc2 |
867 |
{ |
0714a5338 vfs: now it can b... |
868 869 |
struct mount *mnt = real_mount(path->mnt); struct mount *parent; |
1da177e4c Linux-2.6.12-rc2 |
870 |
struct dentry *mountpoint; |
99b7db7b8 fs: brlock vfsmou... |
871 |
|
48a066e72 RCU'd vfsmounts |
872 |
read_seqlock_excl(&mount_lock); |
0714a5338 vfs: now it can b... |
873 |
parent = mnt->mnt_parent; |
3c0a61636 unobfuscate follo... |
874 |
if (parent == mnt) { |
48a066e72 RCU'd vfsmounts |
875 |
read_sequnlock_excl(&mount_lock); |
1da177e4c Linux-2.6.12-rc2 |
876 877 |
return 0; } |
0714a5338 vfs: now it can b... |
878 |
mntget(&parent->mnt); |
a73324da7 vfs: move mnt_mou... |
879 |
mountpoint = dget(mnt->mnt_mountpoint); |
48a066e72 RCU'd vfsmounts |
880 |
read_sequnlock_excl(&mount_lock); |
bab77ebf5 switch follow_up(... |
881 882 883 |
dput(path->dentry); path->dentry = mountpoint; mntput(path->mnt); |
0714a5338 vfs: now it can b... |
884 |
path->mnt = &parent->mnt; |
1da177e4c Linux-2.6.12-rc2 |
885 886 |
return 1; } |
4d3595073 namei.c: move EXP... |
887 |
EXPORT_SYMBOL(follow_up); |
1da177e4c Linux-2.6.12-rc2 |
888 |
|
b5c84bf6f fs: dcache remove... |
889 |
/* |
9875cf806 Add a dentry op t... |
890 891 892 |
* Perform an automount * - return -EISDIR to tell follow_managed() to stop and return the path we * were called with. |
1da177e4c Linux-2.6.12-rc2 |
893 |
*/ |
9875cf806 Add a dentry op t... |
894 895 |
static int follow_automount(struct path *path, unsigned flags, bool *need_mntput) |
31e6b01f4 fs: rcu-walk for ... |
896 |
{ |
9875cf806 Add a dentry op t... |
897 |
struct vfsmount *mnt; |
ea5b778a8 Unexport do_add_m... |
898 |
int err; |
9875cf806 Add a dentry op t... |
899 900 901 |
if (!path->dentry->d_op || !path->dentry->d_op->d_automount) return -EREMOTE; |
0ec26fd06 vfs: automount sh... |
902 903 904 905 906 907 908 909 910 911 |
/* We don't want to mount if someone's just doing a stat - * unless they're stat'ing a directory and appended a '/' to * the name. * * We do, however, want to mount if someone wants to open or * create a file of any type under the mountpoint, wants to * traverse through the mountpoint or wants to open the * mounted directory. Also, autofs may mark negative dentries * as being automount points. These will need the attentions * of the daemon to instantiate them before they can be used. |
9875cf806 Add a dentry op t... |
912 |
*/ |
0ec26fd06 vfs: automount sh... |
913 |
if (!(flags & (LOOKUP_PARENT | LOOKUP_DIRECTORY | |
d94c177be vfs pathname look... |
914 |
LOOKUP_OPEN | LOOKUP_CREATE | LOOKUP_AUTOMOUNT)) && |
0ec26fd06 vfs: automount sh... |
915 916 |
path->dentry->d_inode) return -EISDIR; |
9875cf806 Add a dentry op t... |
917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 |
current->total_link_count++; if (current->total_link_count >= 40) return -ELOOP; mnt = path->dentry->d_op->d_automount(path); if (IS_ERR(mnt)) { /* * The filesystem is allowed to return -EISDIR here to indicate * it doesn't want to automount. For instance, autofs would do * this so that its userspace daemon can mount on this dentry. * * However, we can only permit this if it's a terminal point in * the path being looked up; if it wasn't then the remainder of * the path is inaccessible and we should say so. */ |
49084c3bb kill LOOKUP_CONTINUE |
932 |
if (PTR_ERR(mnt) == -EISDIR && (flags & LOOKUP_PARENT)) |
9875cf806 Add a dentry op t... |
933 934 |
return -EREMOTE; return PTR_ERR(mnt); |
31e6b01f4 fs: rcu-walk for ... |
935 |
} |
ea5b778a8 Unexport do_add_m... |
936 |
|
9875cf806 Add a dentry op t... |
937 938 |
if (!mnt) /* mount collision */ return 0; |
31e6b01f4 fs: rcu-walk for ... |
939 |
|
8aef18845 VFS: Fix vfsmount... |
940 941 942 943 944 |
if (!*need_mntput) { /* lock_mount() may release path->mnt on error */ mntget(path->mnt); *need_mntput = true; } |
19a167af7 Take the completi... |
945 |
err = finish_automount(mnt, path); |
9875cf806 Add a dentry op t... |
946 |
|
ea5b778a8 Unexport do_add_m... |
947 948 949 |
switch (err) { case -EBUSY: /* Someone else made a mount here whilst we were busy */ |
19a167af7 Take the completi... |
950 |
return 0; |
ea5b778a8 Unexport do_add_m... |
951 |
case 0: |
8aef18845 VFS: Fix vfsmount... |
952 |
path_put(path); |
ea5b778a8 Unexport do_add_m... |
953 954 |
path->mnt = mnt; path->dentry = dget(mnt->mnt_root); |
ea5b778a8 Unexport do_add_m... |
955 |
return 0; |
19a167af7 Take the completi... |
956 957 |
default: return err; |
ea5b778a8 Unexport do_add_m... |
958 |
} |
19a167af7 Take the completi... |
959 |
|
463ffb2e9 [PATCH] namei fix... |
960 |
} |
9875cf806 Add a dentry op t... |
961 962 |
/* * Handle a dentry that is managed in some way. |
cc53ce53c Add a dentry op t... |
963 |
* - Flagged for transit management (autofs) |
9875cf806 Add a dentry op t... |
964 965 966 967 968 969 970 971 |
* - Flagged as mountpoint * - Flagged as automount point * * This may only be called in refwalk mode. * * Serialization is taken care of in namespace.c */ static int follow_managed(struct path *path, unsigned flags) |
1da177e4c Linux-2.6.12-rc2 |
972 |
{ |
8aef18845 VFS: Fix vfsmount... |
973 |
struct vfsmount *mnt = path->mnt; /* held by caller, must be left alone */ |
9875cf806 Add a dentry op t... |
974 975 |
unsigned managed; bool need_mntput = false; |
8aef18845 VFS: Fix vfsmount... |
976 |
int ret = 0; |
9875cf806 Add a dentry op t... |
977 978 979 980 981 982 983 |
/* Given that we're not holding a lock here, we retain the value in a * local variable for each dentry as we look at it so that we don't see * the components of that value change under us */ while (managed = ACCESS_ONCE(path->dentry->d_flags), managed &= DCACHE_MANAGED_DENTRY, unlikely(managed != 0)) { |
cc53ce53c Add a dentry op t... |
984 985 986 987 988 |
/* Allow the filesystem to manage the transit without i_mutex * being held. */ if (managed & DCACHE_MANAGE_TRANSIT) { BUG_ON(!path->dentry->d_op); BUG_ON(!path->dentry->d_op->d_manage); |
1aed3e420 lose 'mounting_he... |
989 |
ret = path->dentry->d_op->d_manage(path->dentry, false); |
cc53ce53c Add a dentry op t... |
990 |
if (ret < 0) |
8aef18845 VFS: Fix vfsmount... |
991 |
break; |
cc53ce53c Add a dentry op t... |
992 |
} |
9875cf806 Add a dentry op t... |
993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 |
/* Transit to a mounted filesystem. */ if (managed & DCACHE_MOUNTED) { struct vfsmount *mounted = lookup_mnt(path); if (mounted) { dput(path->dentry); if (need_mntput) mntput(path->mnt); path->mnt = mounted; path->dentry = dget(mounted->mnt_root); need_mntput = true; continue; } /* Something is mounted on this dentry in another * namespace and/or whatever was mounted there in this |
48a066e72 RCU'd vfsmounts |
1008 1009 |
* namespace got unmounted before lookup_mnt() could * get it */ |
9875cf806 Add a dentry op t... |
1010 1011 1012 1013 1014 1015 |
} /* Handle an automount point */ if (managed & DCACHE_NEED_AUTOMOUNT) { ret = follow_automount(path, flags, &need_mntput); if (ret < 0) |
8aef18845 VFS: Fix vfsmount... |
1016 |
break; |
9875cf806 Add a dentry op t... |
1017 1018 1019 1020 1021 |
continue; } /* We didn't change the current path point */ break; |
1da177e4c Linux-2.6.12-rc2 |
1022 |
} |
8aef18845 VFS: Fix vfsmount... |
1023 1024 1025 1026 1027 |
if (need_mntput && path->mnt == mnt) mntput(path->mnt); if (ret == -EISDIR) ret = 0; |
a3fbbde70 VFS: we need to s... |
1028 |
return ret < 0 ? ret : need_mntput; |
1da177e4c Linux-2.6.12-rc2 |
1029 |
} |
cc53ce53c Add a dentry op t... |
1030 |
int follow_down_one(struct path *path) |
1da177e4c Linux-2.6.12-rc2 |
1031 1032 |
{ struct vfsmount *mounted; |
1c755af4d switch lookup_mnt() |
1033 |
mounted = lookup_mnt(path); |
1da177e4c Linux-2.6.12-rc2 |
1034 |
if (mounted) { |
9393bd07c switch follow_down() |
1035 1036 1037 1038 |
dput(path->dentry); mntput(path->mnt); path->mnt = mounted; path->dentry = dget(mounted->mnt_root); |
1da177e4c Linux-2.6.12-rc2 |
1039 1040 1041 1042 |
return 1; } return 0; } |
4d3595073 namei.c: move EXP... |
1043 |
EXPORT_SYMBOL(follow_down_one); |
1da177e4c Linux-2.6.12-rc2 |
1044 |
|
b8faf035e VFS: allow ->d_ma... |
1045 |
static inline int managed_dentry_rcu(struct dentry *dentry) |
62a7375e5 vfs - check non-m... |
1046 |
{ |
b8faf035e VFS: allow ->d_ma... |
1047 1048 |
return (dentry->d_flags & DCACHE_MANAGE_TRANSIT) ? dentry->d_op->d_manage(dentry, true) : 0; |
62a7375e5 vfs - check non-m... |
1049 |
} |
9875cf806 Add a dentry op t... |
1050 |
/* |
287548e46 split __follow_mo... |
1051 1052 |
* Try to skip to top of mountpoint pile in rcuwalk mode. Fail if * we meet a managed dentry that would need blocking. |
9875cf806 Add a dentry op t... |
1053 1054 |
*/ static bool __follow_mount_rcu(struct nameidata *nd, struct path *path, |
287548e46 split __follow_mo... |
1055 |
struct inode **inode) |
9875cf806 Add a dentry op t... |
1056 |
{ |
62a7375e5 vfs - check non-m... |
1057 |
for (;;) { |
c71053659 vfs: spread struc... |
1058 |
struct mount *mounted; |
62a7375e5 vfs - check non-m... |
1059 1060 1061 1062 |
/* * Don't forget we might have a non-mountpoint managed dentry * that wants to block transit. */ |
b8faf035e VFS: allow ->d_ma... |
1063 1064 1065 |
switch (managed_dentry_rcu(path->dentry)) { case -ECHILD: default: |
ab90911ff Allow d_manage() ... |
1066 |
return false; |
b8faf035e VFS: allow ->d_ma... |
1067 1068 1069 1070 1071 |
case -EISDIR: return true; case 0: break; } |
62a7375e5 vfs - check non-m... |
1072 1073 |
if (!d_mountpoint(path->dentry)) |
b8faf035e VFS: allow ->d_ma... |
1074 |
return !(path->dentry->d_flags & DCACHE_NEED_AUTOMOUNT); |
62a7375e5 vfs - check non-m... |
1075 |
|
474279dc0 split __lookup_mn... |
1076 |
mounted = __lookup_mnt(path->mnt, path->dentry); |
9875cf806 Add a dentry op t... |
1077 1078 |
if (!mounted) break; |
c71053659 vfs: spread struc... |
1079 1080 |
path->mnt = &mounted->mnt; path->dentry = mounted->mnt.mnt_root; |
a3fbbde70 VFS: we need to s... |
1081 |
nd->flags |= LOOKUP_JUMPED; |
9875cf806 Add a dentry op t... |
1082 |
nd->seq = read_seqcount_begin(&path->dentry->d_seq); |
594302624 vfs: fix race in ... |
1083 1084 1085 1086 1087 1088 |
/* * Update the inode too. We don't need to re-check the * dentry sequence number here after this d_inode read, * because a mount-point is always pinned. */ *inode = path->dentry->d_inode; |
9875cf806 Add a dentry op t... |
1089 |
} |
b8faf035e VFS: allow ->d_ma... |
1090 1091 |
return read_seqretry(&mount_lock, nd->m_seq) && !(path->dentry->d_flags & DCACHE_NEED_AUTOMOUNT); |
287548e46 split __follow_mo... |
1092 |
} |
31e6b01f4 fs: rcu-walk for ... |
1093 1094 |
static int follow_dotdot_rcu(struct nameidata *nd) { |
31e6b01f4 fs: rcu-walk for ... |
1095 |
set_root_rcu(nd); |
9875cf806 Add a dentry op t... |
1096 |
while (1) { |
31e6b01f4 fs: rcu-walk for ... |
1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 |
if (nd->path.dentry == nd->root.dentry && nd->path.mnt == nd->root.mnt) { break; } if (nd->path.dentry != nd->path.mnt->mnt_root) { struct dentry *old = nd->path.dentry; struct dentry *parent = old->d_parent; unsigned seq; seq = read_seqcount_begin(&parent->d_seq); if (read_seqcount_retry(&old->d_seq, nd->seq)) |
ef7562d52 make handle_dots(... |
1108 |
goto failed; |
31e6b01f4 fs: rcu-walk for ... |
1109 1110 1111 1112 1113 1114 1115 |
nd->path.dentry = parent; nd->seq = seq; break; } if (!follow_up_rcu(&nd->path)) break; nd->seq = read_seqcount_begin(&nd->path.dentry->d_seq); |
31e6b01f4 fs: rcu-walk for ... |
1116 |
} |
b37199e62 rcuwalk: recheck ... |
1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 |
while (d_mountpoint(nd->path.dentry)) { struct mount *mounted; mounted = __lookup_mnt(nd->path.mnt, nd->path.dentry); if (!mounted) break; nd->path.mnt = &mounted->mnt; nd->path.dentry = mounted->mnt.mnt_root; nd->seq = read_seqcount_begin(&nd->path.dentry->d_seq); if (!read_seqretry(&mount_lock, nd->m_seq)) goto failed; } |
dea393761 Trim excessive ar... |
1128 |
nd->inode = nd->path.dentry->d_inode; |
31e6b01f4 fs: rcu-walk for ... |
1129 |
return 0; |
ef7562d52 make handle_dots(... |
1130 1131 1132 |
failed: nd->flags &= ~LOOKUP_RCU; |
5b6ca027d reduce vfs_path_l... |
1133 1134 |
if (!(nd->flags & LOOKUP_ROOT)) nd->root.mnt = NULL; |
8b61e74ff get rid of {lock,... |
1135 |
rcu_read_unlock(); |
ef7562d52 make handle_dots(... |
1136 |
return -ECHILD; |
31e6b01f4 fs: rcu-walk for ... |
1137 |
} |
9875cf806 Add a dentry op t... |
1138 |
/* |
cc53ce53c Add a dentry op t... |
1139 1140 1141 |
* Follow down to the covering mount currently visible to userspace. At each * point, the filesystem owning that dentry may be queried as to whether the * caller is permitted to proceed or not. |
cc53ce53c Add a dentry op t... |
1142 |
*/ |
7cc90cc3f don't pass 'mount... |
1143 |
int follow_down(struct path *path) |
cc53ce53c Add a dentry op t... |
1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 |
{ unsigned managed; int ret; while (managed = ACCESS_ONCE(path->dentry->d_flags), unlikely(managed & DCACHE_MANAGED_DENTRY)) { /* Allow the filesystem to manage the transit without i_mutex * being held. * * We indicate to the filesystem if someone is trying to mount * something here. This gives autofs the chance to deny anyone * other than its daemon the right to mount on its * superstructure. * * The filesystem may sleep at this point. */ if (managed & DCACHE_MANAGE_TRANSIT) { BUG_ON(!path->dentry->d_op); BUG_ON(!path->dentry->d_op->d_manage); |
ab90911ff Allow d_manage() ... |
1163 |
ret = path->dentry->d_op->d_manage( |
1aed3e420 lose 'mounting_he... |
1164 |
path->dentry, false); |
cc53ce53c Add a dentry op t... |
1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 |
if (ret < 0) return ret == -EISDIR ? 0 : ret; } /* Transit to a mounted filesystem. */ if (managed & DCACHE_MOUNTED) { struct vfsmount *mounted = lookup_mnt(path); if (!mounted) break; dput(path->dentry); mntput(path->mnt); path->mnt = mounted; path->dentry = dget(mounted->mnt_root); continue; } /* Don't handle automount points here */ break; } return 0; } |
4d3595073 namei.c: move EXP... |
1186 |
EXPORT_SYMBOL(follow_down); |
cc53ce53c Add a dentry op t... |
1187 1188 |
/* |
9875cf806 Add a dentry op t... |
1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 |
* Skip to top of mountpoint pile in refwalk mode for follow_dotdot() */ static void follow_mount(struct path *path) { while (d_mountpoint(path->dentry)) { struct vfsmount *mounted = lookup_mnt(path); if (!mounted) break; dput(path->dentry); mntput(path->mnt); path->mnt = mounted; path->dentry = dget(mounted->mnt_root); } } |
31e6b01f4 fs: rcu-walk for ... |
1203 |
static void follow_dotdot(struct nameidata *nd) |
1da177e4c Linux-2.6.12-rc2 |
1204 |
{ |
2a7378711 Cache root in nam... |
1205 |
set_root(nd); |
e518ddb7b [PATCH] fs/namei.... |
1206 |
|
1da177e4c Linux-2.6.12-rc2 |
1207 |
while(1) { |
4ac913785 Embed a struct pa... |
1208 |
struct dentry *old = nd->path.dentry; |
1da177e4c Linux-2.6.12-rc2 |
1209 |
|
2a7378711 Cache root in nam... |
1210 1211 |
if (nd->path.dentry == nd->root.dentry && nd->path.mnt == nd->root.mnt) { |
1da177e4c Linux-2.6.12-rc2 |
1212 1213 |
break; } |
4ac913785 Embed a struct pa... |
1214 |
if (nd->path.dentry != nd->path.mnt->mnt_root) { |
3088dd708 Clean follow_dotd... |
1215 1216 |
/* rare case of legitimate dget_parent()... */ nd->path.dentry = dget_parent(nd->path.dentry); |
1da177e4c Linux-2.6.12-rc2 |
1217 1218 1219 |
dput(old); break; } |
3088dd708 Clean follow_dotd... |
1220 |
if (!follow_up(&nd->path)) |
1da177e4c Linux-2.6.12-rc2 |
1221 |
break; |
1da177e4c Linux-2.6.12-rc2 |
1222 |
} |
79ed02261 switch follow_mou... |
1223 |
follow_mount(&nd->path); |
31e6b01f4 fs: rcu-walk for ... |
1224 |
nd->inode = nd->path.dentry->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
1225 |
} |
1da177e4c Linux-2.6.12-rc2 |
1226 |
/* |
bad611897 vfs: split __look... |
1227 1228 1229 1230 1231 |
* This looks up the name in dcache, possibly revalidates the old dentry and * allocates a new one if not found or not valid. In the need_lookup argument * returns whether i_op->lookup is necessary. * * dir->d_inode->i_mutex must be held |
baa038907 fs: dentry alloca... |
1232 |
*/ |
bad611897 vfs: split __look... |
1233 |
static struct dentry *lookup_dcache(struct qstr *name, struct dentry *dir, |
201f956e4 fs/namei.c: don't... |
1234 |
unsigned int flags, bool *need_lookup) |
baa038907 fs: dentry alloca... |
1235 |
{ |
baa038907 fs: dentry alloca... |
1236 |
struct dentry *dentry; |
bad611897 vfs: split __look... |
1237 |
int error; |
baa038907 fs: dentry alloca... |
1238 |
|
bad611897 vfs: split __look... |
1239 1240 1241 |
*need_lookup = false; dentry = d_lookup(dir, name); if (dentry) { |
39e3c9553 vfs: remove DCACH... |
1242 |
if (dentry->d_flags & DCACHE_OP_REVALIDATE) { |
201f956e4 fs/namei.c: don't... |
1243 |
error = d_revalidate(dentry, flags); |
bad611897 vfs: split __look... |
1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 |
if (unlikely(error <= 0)) { if (error < 0) { dput(dentry); return ERR_PTR(error); } else if (!d_invalidate(dentry)) { dput(dentry); dentry = NULL; } } } } |
baa038907 fs: dentry alloca... |
1255 |
|
bad611897 vfs: split __look... |
1256 1257 1258 1259 |
if (!dentry) { dentry = d_alloc(dir, name); if (unlikely(!dentry)) return ERR_PTR(-ENOMEM); |
baa038907 fs: dentry alloca... |
1260 |
|
bad611897 vfs: split __look... |
1261 |
*need_lookup = true; |
baa038907 fs: dentry alloca... |
1262 1263 1264 1265 1266 |
} return dentry; } /* |
13a2c3be0 dcache: fix outda... |
1267 1268 |
* Call i_op->lookup on the dentry. The dentry must be negative and * unhashed. |
bad611897 vfs: split __look... |
1269 1270 |
* * dir->d_inode->i_mutex must be held |
44396f4b5 fs: add a DCACHE_... |
1271 |
*/ |
bad611897 vfs: split __look... |
1272 |
static struct dentry *lookup_real(struct inode *dir, struct dentry *dentry, |
72bd866a0 fs/namei.c: don't... |
1273 |
unsigned int flags) |
44396f4b5 fs: add a DCACHE_... |
1274 |
{ |
44396f4b5 fs: add a DCACHE_... |
1275 1276 1277 |
struct dentry *old; /* Don't create child dentry for a dead directory. */ |
bad611897 vfs: split __look... |
1278 |
if (unlikely(IS_DEADDIR(dir))) { |
e188dc02d vfs: fix d_inode_... |
1279 |
dput(dentry); |
44396f4b5 fs: add a DCACHE_... |
1280 |
return ERR_PTR(-ENOENT); |
e188dc02d vfs: fix d_inode_... |
1281 |
} |
44396f4b5 fs: add a DCACHE_... |
1282 |
|
72bd866a0 fs/namei.c: don't... |
1283 |
old = dir->i_op->lookup(dir, dentry, flags); |
44396f4b5 fs: add a DCACHE_... |
1284 1285 1286 1287 1288 1289 |
if (unlikely(old)) { dput(dentry); dentry = old; } return dentry; } |
a32555466 untangling do_loo... |
1290 |
static struct dentry *__lookup_hash(struct qstr *name, |
72bd866a0 fs/namei.c: don't... |
1291 |
struct dentry *base, unsigned int flags) |
a32555466 untangling do_loo... |
1292 |
{ |
bad611897 vfs: split __look... |
1293 |
bool need_lookup; |
a32555466 untangling do_loo... |
1294 |
struct dentry *dentry; |
72bd866a0 fs/namei.c: don't... |
1295 |
dentry = lookup_dcache(name, base, flags, &need_lookup); |
bad611897 vfs: split __look... |
1296 1297 |
if (!need_lookup) return dentry; |
a32555466 untangling do_loo... |
1298 |
|
72bd866a0 fs/namei.c: don't... |
1299 |
return lookup_real(base->d_inode, dentry, flags); |
a32555466 untangling do_loo... |
1300 |
} |
44396f4b5 fs: add a DCACHE_... |
1301 |
/* |
1da177e4c Linux-2.6.12-rc2 |
1302 1303 1304 1305 |
* It's more convoluted than I'd like it to be, but... it's still fairly * small and for now I'd prefer to have fast path as straight as possible. * It _is_ time-critical. */ |
e97cdc87b lookup_fast: get ... |
1306 |
static int lookup_fast(struct nameidata *nd, |
697f514df vfs: split do_loo... |
1307 |
struct path *path, struct inode **inode) |
1da177e4c Linux-2.6.12-rc2 |
1308 |
{ |
4ac913785 Embed a struct pa... |
1309 |
struct vfsmount *mnt = nd->path.mnt; |
31e6b01f4 fs: rcu-walk for ... |
1310 |
struct dentry *dentry, *parent = nd->path.dentry; |
5a18fff20 untangle do_lookup() |
1311 1312 |
int need_reval = 1; int status = 1; |
9875cf806 Add a dentry op t... |
1313 |
int err; |
3cac260ad Take hash recalcu... |
1314 |
/* |
b04f784e5 fs: remove extra ... |
1315 1316 1317 1318 |
* Rename seqlock is not required here because in the off chance * of a false negative due to a concurrent rename, we're going to * do the non-racy lookup, below. */ |
31e6b01f4 fs: rcu-walk for ... |
1319 1320 |
if (nd->flags & LOOKUP_RCU) { unsigned seq; |
da53be12b Don't pass inode ... |
1321 |
dentry = __d_lookup_rcu(parent, &nd->last, &seq); |
5a18fff20 untangle do_lookup() |
1322 1323 |
if (!dentry) goto unlazy; |
12f8ad4b0 vfs: clean up __d... |
1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 |
/* * This sequence count validates that the inode matches * the dentry name information from lookup. */ *inode = dentry->d_inode; if (read_seqcount_retry(&dentry->d_seq, seq)) return -ECHILD; /* * This sequence count validates that the parent had no * changes while we did the lookup of the dentry above. * * The memory barrier in read_seqcount_begin of child is * enough, we can use __read_seqcount_retry here. */ |
31e6b01f4 fs: rcu-walk for ... |
1339 1340 |
if (__read_seqcount_retry(&parent->d_seq, nd->seq)) return -ECHILD; |
31e6b01f4 fs: rcu-walk for ... |
1341 |
nd->seq = seq; |
5a18fff20 untangle do_lookup() |
1342 |
|
24643087e in do_lookup() sp... |
1343 |
if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE)) { |
4ce16ef3f fs/namei.c: don't... |
1344 |
status = d_revalidate(dentry, nd->flags); |
5a18fff20 untangle do_lookup() |
1345 1346 1347 1348 1349 |
if (unlikely(status <= 0)) { if (status != -ECHILD) need_reval = 0; goto unlazy; } |
24643087e in do_lookup() sp... |
1350 |
} |
31e6b01f4 fs: rcu-walk for ... |
1351 1352 |
path->mnt = mnt; path->dentry = dentry; |
b8faf035e VFS: allow ->d_ma... |
1353 1354 |
if (likely(__follow_mount_rcu(nd, path, inode))) return 0; |
5a18fff20 untangle do_lookup() |
1355 |
unlazy: |
19660af73 consolidate namei... |
1356 1357 |
if (unlazy_walk(nd, dentry)) return -ECHILD; |
5a18fff20 untangle do_lookup() |
1358 |
} else { |
e97cdc87b lookup_fast: get ... |
1359 |
dentry = __d_lookup(parent, &nd->last); |
9875cf806 Add a dentry op t... |
1360 |
} |
5a18fff20 untangle do_lookup() |
1361 |
|
81e6f5208 untangling do_loo... |
1362 1363 |
if (unlikely(!dentry)) goto need_lookup; |
5a18fff20 untangle do_lookup() |
1364 |
if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE) && need_reval) |
4ce16ef3f fs/namei.c: don't... |
1365 |
status = d_revalidate(dentry, nd->flags); |
5a18fff20 untangle do_lookup() |
1366 1367 1368 1369 1370 1371 1372 |
if (unlikely(status <= 0)) { if (status < 0) { dput(dentry); return status; } if (!d_invalidate(dentry)) { dput(dentry); |
81e6f5208 untangling do_loo... |
1373 |
goto need_lookup; |
5a18fff20 untangle do_lookup() |
1374 |
} |
24643087e in do_lookup() sp... |
1375 |
} |
697f514df vfs: split do_loo... |
1376 |
|
9875cf806 Add a dentry op t... |
1377 1378 1379 |
path->mnt = mnt; path->dentry = dentry; err = follow_managed(path, nd->flags); |
893122141 vfs - fix dentry ... |
1380 1381 |
if (unlikely(err < 0)) { path_put_conditional(path, nd); |
9875cf806 Add a dentry op t... |
1382 |
return err; |
893122141 vfs - fix dentry ... |
1383 |
} |
a3fbbde70 VFS: we need to s... |
1384 1385 |
if (err) nd->flags |= LOOKUP_JUMPED; |
9875cf806 Add a dentry op t... |
1386 |
*inode = path->dentry->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
1387 |
return 0; |
81e6f5208 untangling do_loo... |
1388 1389 |
need_lookup: |
697f514df vfs: split do_loo... |
1390 1391 1392 1393 |
return 1; } /* Fast lookup failed, do it the slow way */ |
cc2a52711 lookup_slow: get ... |
1394 |
static int lookup_slow(struct nameidata *nd, struct path *path) |
697f514df vfs: split do_loo... |
1395 1396 1397 1398 1399 |
{ struct dentry *dentry, *parent; int err; parent = nd->path.dentry; |
81e6f5208 untangling do_loo... |
1400 1401 1402 |
BUG_ON(nd->inode != parent->d_inode); mutex_lock(&parent->d_inode->i_mutex); |
cc2a52711 lookup_slow: get ... |
1403 |
dentry = __lookup_hash(&nd->last, parent, nd->flags); |
81e6f5208 untangling do_loo... |
1404 1405 1406 |
mutex_unlock(&parent->d_inode->i_mutex); if (IS_ERR(dentry)) return PTR_ERR(dentry); |
697f514df vfs: split do_loo... |
1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 |
path->mnt = nd->path.mnt; path->dentry = dentry; err = follow_managed(path, nd->flags); if (unlikely(err < 0)) { path_put_conditional(path, nd); return err; } if (err) nd->flags |= LOOKUP_JUMPED; return 0; |
1da177e4c Linux-2.6.12-rc2 |
1417 |
} |
52094c8a0 take RCU-dependen... |
1418 1419 1420 |
static inline int may_lookup(struct nameidata *nd) { if (nd->flags & LOOKUP_RCU) { |
4ad5abb3d no reason to keep... |
1421 |
int err = inode_permission(nd->inode, MAY_EXEC|MAY_NOT_BLOCK); |
52094c8a0 take RCU-dependen... |
1422 1423 |
if (err != -ECHILD) return err; |
19660af73 consolidate namei... |
1424 |
if (unlazy_walk(nd, NULL)) |
52094c8a0 take RCU-dependen... |
1425 1426 |
return -ECHILD; } |
4ad5abb3d no reason to keep... |
1427 |
return inode_permission(nd->inode, MAY_EXEC); |
52094c8a0 take RCU-dependen... |
1428 |
} |
9856fa1b2 pull handling of ... |
1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 |
static inline int handle_dots(struct nameidata *nd, int type) { if (type == LAST_DOTDOT) { if (nd->flags & LOOKUP_RCU) { if (follow_dotdot_rcu(nd)) return -ECHILD; } else follow_dotdot(nd); } return 0; } |
951361f95 get rid of the la... |
1440 1441 1442 1443 1444 1445 |
static void terminate_walk(struct nameidata *nd) { if (!(nd->flags & LOOKUP_RCU)) { path_put(&nd->path); } else { nd->flags &= ~LOOKUP_RCU; |
5b6ca027d reduce vfs_path_l... |
1446 1447 |
if (!(nd->flags & LOOKUP_ROOT)) nd->root.mnt = NULL; |
8b61e74ff get rid of {lock,... |
1448 |
rcu_read_unlock(); |
951361f95 get rid of the la... |
1449 1450 |
} } |
3ddcd0569 vfs: optimize ino... |
1451 1452 1453 1454 1455 1456 |
/* * Do we need to follow links? We _really_ want to be able * to do this check without having to look at inode->i_op, * so we keep a cache of "no, this doesn't need follow_link" * for the common case. */ |
b18825a7c VFS: Put a small ... |
1457 |
static inline int should_follow_link(struct dentry *dentry, int follow) |
3ddcd0569 vfs: optimize ino... |
1458 |
{ |
b18825a7c VFS: Put a small ... |
1459 |
return unlikely(d_is_symlink(dentry)) ? follow : 0; |
3ddcd0569 vfs: optimize ino... |
1460 |
} |
ce57dfc17 pull handling of ... |
1461 |
static inline int walk_component(struct nameidata *nd, struct path *path, |
21b9b0739 get rid of name a... |
1462 |
int follow) |
ce57dfc17 pull handling of ... |
1463 1464 1465 1466 1467 1468 1469 1470 |
{ struct inode *inode; int err; /* * "." and ".." are special - ".." especially so because it has * to be able to know about the current root directory and * parent relationships. */ |
21b9b0739 get rid of name a... |
1471 1472 |
if (unlikely(nd->last_type != LAST_NORM)) return handle_dots(nd, nd->last_type); |
e97cdc87b lookup_fast: get ... |
1473 |
err = lookup_fast(nd, path, &inode); |
ce57dfc17 pull handling of ... |
1474 |
if (unlikely(err)) { |
697f514df vfs: split do_loo... |
1475 1476 |
if (err < 0) goto out_err; |
cc2a52711 lookup_slow: get ... |
1477 |
err = lookup_slow(nd, path); |
697f514df vfs: split do_loo... |
1478 1479 1480 1481 |
if (err < 0) goto out_err; inode = path->dentry->d_inode; |
ce57dfc17 pull handling of ... |
1482 |
} |
697f514df vfs: split do_loo... |
1483 |
err = -ENOENT; |
22213318a fix races between... |
1484 |
if (!inode || d_is_negative(path->dentry)) |
697f514df vfs: split do_loo... |
1485 |
goto out_path_put; |
b18825a7c VFS: Put a small ... |
1486 |
if (should_follow_link(path->dentry, follow)) { |
19660af73 consolidate namei... |
1487 1488 |
if (nd->flags & LOOKUP_RCU) { if (unlikely(unlazy_walk(nd, path->dentry))) { |
697f514df vfs: split do_loo... |
1489 1490 |
err = -ECHILD; goto out_err; |
19660af73 consolidate namei... |
1491 1492 |
} } |
ce57dfc17 pull handling of ... |
1493 1494 1495 1496 1497 1498 |
BUG_ON(inode != path->dentry->d_inode); return 1; } path_to_nameidata(path, nd); nd->inode = inode; return 0; |
697f514df vfs: split do_loo... |
1499 1500 1501 1502 1503 1504 |
out_path_put: path_to_nameidata(path, nd); out_err: terminate_walk(nd); return err; |
ce57dfc17 pull handling of ... |
1505 |
} |
1da177e4c Linux-2.6.12-rc2 |
1506 |
/* |
b356379a0 Turn resolution o... |
1507 1508 1509 1510 1511 1512 1513 1514 1515 |
* This limits recursive symlink follows to 8, while * limiting consecutive symlinks to 40. * * Without that kind of total limit, nasty chains of consecutive * symlinks can cause almost arbitrarily long lookups. */ static inline int nested_symlink(struct path *path, struct nameidata *nd) { int res; |
b356379a0 Turn resolution o... |
1516 1517 1518 1519 1520 |
if (unlikely(current->link_count >= MAX_NESTED_LINKS)) { path_put_conditional(path, nd); path_put(&nd->path); return -ELOOP; } |
1a4022f88 VFS: move BUG_ON ... |
1521 |
BUG_ON(nd->depth >= MAX_NESTED_LINKS); |
b356379a0 Turn resolution o... |
1522 1523 1524 1525 1526 1527 1528 |
nd->depth++; current->link_count++; do { struct path link = *path; void *cookie; |
574197e0d tidy the trailing... |
1529 1530 |
res = follow_link(&link, nd, &cookie); |
6d7b5aaed namei.c: let foll... |
1531 1532 |
if (res) break; |
21b9b0739 get rid of name a... |
1533 |
res = walk_component(nd, path, LOOKUP_FOLLOW); |
574197e0d tidy the trailing... |
1534 |
put_link(nd, &link, cookie); |
b356379a0 Turn resolution o... |
1535 1536 1537 1538 1539 1540 1541 1542 |
} while (res > 0); current->link_count--; nd->depth--; return res; } /* |
bfcfaa77b vfs: use 'unsigne... |
1543 1544 1545 1546 1547 1548 1549 |
* We can do the critical dentry name comparison and hashing * operations one word at a time, but we are limited to: * * - Architectures with fast unaligned word accesses. We could * do a "get_unaligned()" if this helps and is sufficiently * fast. * |
bfcfaa77b vfs: use 'unsigne... |
1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 |
* - non-CONFIG_DEBUG_PAGEALLOC configurations (so that we * do not trap on the (extremely unlikely) case of a page * crossing operation. * * - Furthermore, we need an efficient 64-bit compile for the * 64-bit case in order to generate the "number of bytes in * the final mask". Again, that could be replaced with a * efficient population count instruction or similar. */ #ifdef CONFIG_DCACHE_WORD_ACCESS |
f68e556e2 Make the "word-at... |
1560 |
#include <asm/word-at-a-time.h> |
bfcfaa77b vfs: use 'unsigne... |
1561 |
|
f68e556e2 Make the "word-at... |
1562 |
#ifdef CONFIG_64BIT |
bfcfaa77b vfs: use 'unsigne... |
1563 1564 1565 1566 1567 1568 1569 1570 |
static inline unsigned int fold_hash(unsigned long hash) { hash += hash >> (8*sizeof(int)); return hash; } #else /* 32-bit case */ |
bfcfaa77b vfs: use 'unsigne... |
1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 |
#define fold_hash(x) (x) #endif unsigned int full_name_hash(const unsigned char *name, unsigned int len) { unsigned long a, mask; unsigned long hash = 0; for (;;) { |
e419b4cc5 vfs: make word-at... |
1581 |
a = load_unaligned_zeropad(name); |
bfcfaa77b vfs: use 'unsigne... |
1582 1583 1584 |
if (len < sizeof(unsigned long)) break; hash += a; |
f132c5be0 Fix full_name_has... |
1585 |
hash *= 9; |
bfcfaa77b vfs: use 'unsigne... |
1586 1587 1588 1589 1590 |
name += sizeof(unsigned long); len -= sizeof(unsigned long); if (!len) goto done; } |
a5c21dcef dcache: allow wor... |
1591 |
mask = bytemask_from_count(len); |
bfcfaa77b vfs: use 'unsigne... |
1592 1593 1594 1595 1596 |
hash += mask & a; done: return fold_hash(hash); } EXPORT_SYMBOL(full_name_hash); |
bfcfaa77b vfs: use 'unsigne... |
1597 1598 1599 1600 1601 1602 |
/* * Calculate the length and hash of the path component, and * return the length of the component; */ static inline unsigned long hash_name(const char *name, unsigned int *hashp) { |
36126f8f2 word-at-a-time: m... |
1603 1604 |
unsigned long a, b, adata, bdata, mask, hash, len; const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS; |
bfcfaa77b vfs: use 'unsigne... |
1605 1606 1607 1608 1609 1610 |
hash = a = 0; len = -sizeof(unsigned long); do { hash = (hash + a) * 9; len += sizeof(unsigned long); |
e419b4cc5 vfs: make word-at... |
1611 |
a = load_unaligned_zeropad(name+len); |
36126f8f2 word-at-a-time: m... |
1612 1613 1614 1615 1616 1617 1618 1619 1620 |
b = a ^ REPEAT_BYTE('/'); } while (!(has_zero(a, &adata, &constants) | has_zero(b, &bdata, &constants))); adata = prep_zero_mask(a, adata, &constants); bdata = prep_zero_mask(b, bdata, &constants); mask = create_zero_mask(adata | bdata); hash += a & zero_bytemask(mask); |
bfcfaa77b vfs: use 'unsigne... |
1621 |
*hashp = fold_hash(hash); |
36126f8f2 word-at-a-time: m... |
1622 |
return len + find_zero(mask); |
bfcfaa77b vfs: use 'unsigne... |
1623 1624 1625 |
} #else |
0145acc20 vfs: uninline ful... |
1626 1627 1628 1629 1630 1631 1632 |
unsigned int full_name_hash(const unsigned char *name, unsigned int len) { unsigned long hash = init_name_hash(); while (len--) hash = partial_name_hash(*name++, hash); return end_name_hash(hash); } |
ae942ae71 vfs: export full_... |
1633 |
EXPORT_SYMBOL(full_name_hash); |
0145acc20 vfs: uninline ful... |
1634 |
|
3ddcd0569 vfs: optimize ino... |
1635 |
/* |
200e9ef7a vfs: split up nam... |
1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 |
* We know there's a real path component here of at least * one character. */ static inline unsigned long hash_name(const char *name, unsigned int *hashp) { unsigned long hash = init_name_hash(); unsigned long len = 0, c; c = (unsigned char)*name; do { len++; hash = partial_name_hash(c, hash); c = (unsigned char)name[len]; } while (c && c != '/'); *hashp = end_name_hash(hash); return len; } |
bfcfaa77b vfs: use 'unsigne... |
1653 |
#endif |
200e9ef7a vfs: split up nam... |
1654 |
/* |
1da177e4c Linux-2.6.12-rc2 |
1655 |
* Name resolution. |
ea3834d9f namei: add audit_... |
1656 1657 |
* This is the basic name resolution function, turning a pathname into * the final dentry. We expect 'base' to be positive and a directory. |
1da177e4c Linux-2.6.12-rc2 |
1658 |
* |
ea3834d9f namei: add audit_... |
1659 1660 |
* Returns 0 and nd will have valid dentry and mnt on success. * Returns error and drops reference to input namei data on failure. |
1da177e4c Linux-2.6.12-rc2 |
1661 |
*/ |
6de88d729 kill __link_path_... |
1662 |
static int link_path_walk(const char *name, struct nameidata *nd) |
1da177e4c Linux-2.6.12-rc2 |
1663 1664 |
{ struct path next; |
1da177e4c Linux-2.6.12-rc2 |
1665 |
int err; |
1da177e4c Linux-2.6.12-rc2 |
1666 1667 1668 1669 |
while (*name=='/') name++; if (!*name) |
086e183a6 pull dropping RCU... |
1670 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
1671 |
|
1da177e4c Linux-2.6.12-rc2 |
1672 1673 |
/* At this point we know we have a real path component. */ for(;;) { |
1da177e4c Linux-2.6.12-rc2 |
1674 |
struct qstr this; |
200e9ef7a vfs: split up nam... |
1675 |
long len; |
fe479a580 merge component t... |
1676 |
int type; |
1da177e4c Linux-2.6.12-rc2 |
1677 |
|
52094c8a0 take RCU-dependen... |
1678 |
err = may_lookup(nd); |
1da177e4c Linux-2.6.12-rc2 |
1679 1680 |
if (err) break; |
200e9ef7a vfs: split up nam... |
1681 |
len = hash_name(name, &this.hash); |
1da177e4c Linux-2.6.12-rc2 |
1682 |
this.name = name; |
200e9ef7a vfs: split up nam... |
1683 |
this.len = len; |
1da177e4c Linux-2.6.12-rc2 |
1684 |
|
fe479a580 merge component t... |
1685 |
type = LAST_NORM; |
200e9ef7a vfs: split up nam... |
1686 |
if (name[0] == '.') switch (len) { |
fe479a580 merge component t... |
1687 |
case 2: |
200e9ef7a vfs: split up nam... |
1688 |
if (name[1] == '.') { |
fe479a580 merge component t... |
1689 |
type = LAST_DOTDOT; |
16c2cd717 untangle the "nee... |
1690 1691 |
nd->flags |= LOOKUP_JUMPED; } |
fe479a580 merge component t... |
1692 1693 1694 1695 |
break; case 1: type = LAST_DOT; } |
5a202bcd7 sanitize pathname... |
1696 1697 |
if (likely(type == LAST_NORM)) { struct dentry *parent = nd->path.dentry; |
16c2cd717 untangle the "nee... |
1698 |
nd->flags &= ~LOOKUP_JUMPED; |
5a202bcd7 sanitize pathname... |
1699 |
if (unlikely(parent->d_flags & DCACHE_OP_HASH)) { |
da53be12b Don't pass inode ... |
1700 |
err = parent->d_op->d_hash(parent, &this); |
5a202bcd7 sanitize pathname... |
1701 1702 1703 1704 |
if (err < 0) break; } } |
fe479a580 merge component t... |
1705 |
|
5f4a6a695 link_path_walk():... |
1706 1707 |
nd->last = this; nd->last_type = type; |
200e9ef7a vfs: split up nam... |
1708 |
if (!name[len]) |
5f4a6a695 link_path_walk():... |
1709 |
return 0; |
200e9ef7a vfs: split up nam... |
1710 1711 1712 1713 1714 1715 1716 1717 |
/* * If it wasn't NUL, we know it was '/'. Skip that * slash, and continue until no more slashes. */ do { len++; } while (unlikely(name[len] == '/')); if (!name[len]) |
5f4a6a695 link_path_walk():... |
1718 |
return 0; |
200e9ef7a vfs: split up nam... |
1719 |
name += len; |
1da177e4c Linux-2.6.12-rc2 |
1720 |
|
21b9b0739 get rid of name a... |
1721 |
err = walk_component(nd, &next, LOOKUP_FOLLOW); |
ce57dfc17 pull handling of ... |
1722 1723 |
if (err < 0) return err; |
1da177e4c Linux-2.6.12-rc2 |
1724 |
|
ce57dfc17 pull handling of ... |
1725 |
if (err) { |
b356379a0 Turn resolution o... |
1726 |
err = nested_symlink(&next, nd); |
1da177e4c Linux-2.6.12-rc2 |
1727 |
if (err) |
a7472baba make nameidata_de... |
1728 |
return err; |
31e6b01f4 fs: rcu-walk for ... |
1729 |
} |
44b1d5304 vfs: add d_is_dir() |
1730 |
if (!d_can_lookup(nd->path.dentry)) { |
5f4a6a695 link_path_walk():... |
1731 1732 1733 |
err = -ENOTDIR; break; } |
1da177e4c Linux-2.6.12-rc2 |
1734 |
} |
951361f95 get rid of the la... |
1735 |
terminate_walk(nd); |
1da177e4c Linux-2.6.12-rc2 |
1736 1737 |
return err; } |
70e9b3571 get rid of nd->file |
1738 1739 |
static int path_init(int dfd, const char *name, unsigned int flags, struct nameidata *nd, struct file **fp) |
31e6b01f4 fs: rcu-walk for ... |
1740 1741 |
{ int retval = 0; |
31e6b01f4 fs: rcu-walk for ... |
1742 1743 |
nd->last_type = LAST_ROOT; /* if there are only slashes... */ |
16c2cd717 untangle the "nee... |
1744 |
nd->flags = flags | LOOKUP_JUMPED; |
31e6b01f4 fs: rcu-walk for ... |
1745 |
nd->depth = 0; |
5b6ca027d reduce vfs_path_l... |
1746 |
if (flags & LOOKUP_ROOT) { |
b18825a7c VFS: Put a small ... |
1747 1748 |
struct dentry *root = nd->root.dentry; struct inode *inode = root->d_inode; |
73d049a40 open-style analog... |
1749 |
if (*name) { |
44b1d5304 vfs: add d_is_dir() |
1750 |
if (!d_can_lookup(root)) |
73d049a40 open-style analog... |
1751 1752 1753 1754 1755 |
return -ENOTDIR; retval = inode_permission(inode, MAY_EXEC); if (retval) return retval; } |
5b6ca027d reduce vfs_path_l... |
1756 1757 1758 |
nd->path = nd->root; nd->inode = inode; if (flags & LOOKUP_RCU) { |
8b61e74ff get rid of {lock,... |
1759 |
rcu_read_lock(); |
5b6ca027d reduce vfs_path_l... |
1760 |
nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq); |
48a066e72 RCU'd vfsmounts |
1761 |
nd->m_seq = read_seqbegin(&mount_lock); |
5b6ca027d reduce vfs_path_l... |
1762 1763 1764 1765 1766 |
} else { path_get(&nd->path); } return 0; } |
31e6b01f4 fs: rcu-walk for ... |
1767 |
nd->root.mnt = NULL; |
31e6b01f4 fs: rcu-walk for ... |
1768 |
|
48a066e72 RCU'd vfsmounts |
1769 |
nd->m_seq = read_seqbegin(&mount_lock); |
31e6b01f4 fs: rcu-walk for ... |
1770 |
if (*name=='/') { |
e41f7d4ee merge path_init a... |
1771 |
if (flags & LOOKUP_RCU) { |
8b61e74ff get rid of {lock,... |
1772 |
rcu_read_lock(); |
e41f7d4ee merge path_init a... |
1773 1774 1775 1776 1777 1778 |
set_root_rcu(nd); } else { set_root(nd); path_get(&nd->root); } nd->path = nd->root; |
31e6b01f4 fs: rcu-walk for ... |
1779 |
} else if (dfd == AT_FDCWD) { |
e41f7d4ee merge path_init a... |
1780 1781 1782 |
if (flags & LOOKUP_RCU) { struct fs_struct *fs = current->fs; unsigned seq; |
31e6b01f4 fs: rcu-walk for ... |
1783 |
|
8b61e74ff get rid of {lock,... |
1784 |
rcu_read_lock(); |
c28cc3646 fs: fs_struct use... |
1785 |
|
e41f7d4ee merge path_init a... |
1786 1787 1788 1789 1790 1791 1792 1793 |
do { seq = read_seqcount_begin(&fs->seq); nd->path = fs->pwd; nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq); } while (read_seqcount_retry(&fs->seq, seq)); } else { get_fs_pwd(current->fs, &nd->path); } |
31e6b01f4 fs: rcu-walk for ... |
1794 |
} else { |
582aa64a0 vfs: remove unnee... |
1795 |
/* Caller must check execute permissions on the starting path component */ |
2903ff019 switch simple cas... |
1796 |
struct fd f = fdget_raw(dfd); |
31e6b01f4 fs: rcu-walk for ... |
1797 |
struct dentry *dentry; |
2903ff019 switch simple cas... |
1798 1799 |
if (!f.file) return -EBADF; |
31e6b01f4 fs: rcu-walk for ... |
1800 |
|
2903ff019 switch simple cas... |
1801 |
dentry = f.file->f_path.dentry; |
31e6b01f4 fs: rcu-walk for ... |
1802 |
|
f52e0c113 New AT_... flag: ... |
1803 |
if (*name) { |
44b1d5304 vfs: add d_is_dir() |
1804 |
if (!d_can_lookup(dentry)) { |
2903ff019 switch simple cas... |
1805 1806 1807 |
fdput(f); return -ENOTDIR; } |
f52e0c113 New AT_... flag: ... |
1808 |
} |
31e6b01f4 fs: rcu-walk for ... |
1809 |
|
2903ff019 switch simple cas... |
1810 |
nd->path = f.file->f_path; |
e41f7d4ee merge path_init a... |
1811 |
if (flags & LOOKUP_RCU) { |
9c225f265 vfs: atomic f_pos... |
1812 |
if (f.flags & FDPUT_FPUT) |
2903ff019 switch simple cas... |
1813 |
*fp = f.file; |
e41f7d4ee merge path_init a... |
1814 |
nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq); |
8b61e74ff get rid of {lock,... |
1815 |
rcu_read_lock(); |
e41f7d4ee merge path_init a... |
1816 |
} else { |
2903ff019 switch simple cas... |
1817 1818 |
path_get(&nd->path); fdput(f); |
e41f7d4ee merge path_init a... |
1819 |
} |
31e6b01f4 fs: rcu-walk for ... |
1820 |
} |
31e6b01f4 fs: rcu-walk for ... |
1821 |
|
31e6b01f4 fs: rcu-walk for ... |
1822 |
nd->inode = nd->path.dentry->d_inode; |
9b4a9b14a Preparations to c... |
1823 |
return 0; |
9b4a9b14a Preparations to c... |
1824 |
} |
bd92d7fed Make trailing sym... |
1825 1826 1827 1828 1829 1830 |
static inline int lookup_last(struct nameidata *nd, struct path *path) { if (nd->last_type == LAST_NORM && nd->last.name[nd->last.len]) nd->flags |= LOOKUP_FOLLOW | LOOKUP_DIRECTORY; nd->flags &= ~LOOKUP_PARENT; |
21b9b0739 get rid of name a... |
1831 |
return walk_component(nd, path, nd->flags & LOOKUP_FOLLOW); |
bd92d7fed Make trailing sym... |
1832 |
} |
9b4a9b14a Preparations to c... |
1833 |
/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */ |
ee0827cd6 sanitize path_wal... |
1834 |
static int path_lookupat(int dfd, const char *name, |
9b4a9b14a Preparations to c... |
1835 1836 |
unsigned int flags, struct nameidata *nd) { |
70e9b3571 get rid of nd->file |
1837 |
struct file *base = NULL; |
bd92d7fed Make trailing sym... |
1838 1839 |
struct path path; int err; |
31e6b01f4 fs: rcu-walk for ... |
1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 |
/* * Path walking is largely split up into 2 different synchronisation * schemes, rcu-walk and ref-walk (explained in * Documentation/filesystems/path-lookup.txt). These share much of the * path walk code, but some things particularly setup, cleanup, and * following mounts are sufficiently divergent that functions are * duplicated. Typically there is a function foo(), and its RCU * analogue, foo_rcu(). * * -ECHILD is the error number of choice (just to avoid clashes) that * is returned if some aspect of an rcu-walk fails. Such an error must * be handled by restarting a traditional ref-walk (which will always * be able to complete). */ |
bd92d7fed Make trailing sym... |
1855 |
err = path_init(dfd, name, flags | LOOKUP_PARENT, nd, &base); |
ee0827cd6 sanitize path_wal... |
1856 |
|
bd92d7fed Make trailing sym... |
1857 1858 |
if (unlikely(err)) return err; |
ee0827cd6 sanitize path_wal... |
1859 1860 |
current->total_link_count = 0; |
bd92d7fed Make trailing sym... |
1861 1862 1863 |
err = link_path_walk(name, nd); if (!err && !(flags & LOOKUP_PARENT)) { |
bd92d7fed Make trailing sym... |
1864 1865 1866 1867 |
err = lookup_last(nd, &path); while (err > 0) { void *cookie; struct path link = path; |
800179c9b fs: add link rest... |
1868 1869 1870 |
err = may_follow_link(&link, nd); if (unlikely(err)) break; |
bd92d7fed Make trailing sym... |
1871 |
nd->flags |= LOOKUP_PARENT; |
574197e0d tidy the trailing... |
1872 |
err = follow_link(&link, nd, &cookie); |
6d7b5aaed namei.c: let foll... |
1873 1874 1875 |
if (err) break; err = lookup_last(nd, &path); |
574197e0d tidy the trailing... |
1876 |
put_link(nd, &link, cookie); |
bd92d7fed Make trailing sym... |
1877 1878 |
} } |
ee0827cd6 sanitize path_wal... |
1879 |
|
9f1fafee9 merge handle_reva... |
1880 1881 |
if (!err) err = complete_walk(nd); |
bd92d7fed Make trailing sym... |
1882 1883 |
if (!err && nd->flags & LOOKUP_DIRECTORY) { |
44b1d5304 vfs: add d_is_dir() |
1884 |
if (!d_can_lookup(nd->path.dentry)) { |
bd92d7fed Make trailing sym... |
1885 |
path_put(&nd->path); |
bd23a539d fix leaks in path... |
1886 |
err = -ENOTDIR; |
bd92d7fed Make trailing sym... |
1887 1888 |
} } |
16c2cd717 untangle the "nee... |
1889 |
|
70e9b3571 get rid of nd->file |
1890 1891 |
if (base) fput(base); |
ee0827cd6 sanitize path_wal... |
1892 |
|
5b6ca027d reduce vfs_path_l... |
1893 |
if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) { |
2a7378711 Cache root in nam... |
1894 1895 1896 |
path_put(&nd->root); nd->root.mnt = NULL; } |
bd92d7fed Make trailing sym... |
1897 |
return err; |
ee0827cd6 sanitize path_wal... |
1898 |
} |
31e6b01f4 fs: rcu-walk for ... |
1899 |
|
873f1eedc vfs: turn do_path... |
1900 |
static int filename_lookup(int dfd, struct filename *name, |
ee0827cd6 sanitize path_wal... |
1901 1902 |
unsigned int flags, struct nameidata *nd) { |
873f1eedc vfs: turn do_path... |
1903 |
int retval = path_lookupat(dfd, name->name, flags | LOOKUP_RCU, nd); |
ee0827cd6 sanitize path_wal... |
1904 |
if (unlikely(retval == -ECHILD)) |
873f1eedc vfs: turn do_path... |
1905 |
retval = path_lookupat(dfd, name->name, flags, nd); |
ee0827cd6 sanitize path_wal... |
1906 |
if (unlikely(retval == -ESTALE)) |
873f1eedc vfs: turn do_path... |
1907 1908 |
retval = path_lookupat(dfd, name->name, flags | LOOKUP_REVAL, nd); |
31e6b01f4 fs: rcu-walk for ... |
1909 |
|
f78570dd6 audit: remove unn... |
1910 |
if (likely(!retval)) |
adb5c2473 audit: make audit... |
1911 |
audit_inode(name, nd->path.dentry, flags & LOOKUP_PARENT); |
170aa3d02 [PATCH] namei.c: ... |
1912 |
return retval; |
1da177e4c Linux-2.6.12-rc2 |
1913 |
} |
873f1eedc vfs: turn do_path... |
1914 1915 1916 1917 1918 1919 1920 |
static int do_path_lookup(int dfd, const char *name, unsigned int flags, struct nameidata *nd) { struct filename filename = { .name = name }; return filename_lookup(dfd, &filename, flags, nd); } |
79714f72d get rid of kern_p... |
1921 1922 |
/* does lookup, returns the object with parent locked */ struct dentry *kern_path_locked(const char *name, struct path *path) |
5590ff0d5 [PATCH] vfs: *at ... |
1923 |
{ |
79714f72d get rid of kern_p... |
1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 |
struct nameidata nd; struct dentry *d; int err = do_path_lookup(AT_FDCWD, name, LOOKUP_PARENT, &nd); if (err) return ERR_PTR(err); if (nd.last_type != LAST_NORM) { path_put(&nd.path); return ERR_PTR(-EINVAL); } mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); |
1e0ea0014 use __lookup_hash... |
1934 |
d = __lookup_hash(&nd.last, nd.path.dentry, 0); |
79714f72d get rid of kern_p... |
1935 1936 1937 1938 1939 1940 1941 |
if (IS_ERR(d)) { mutex_unlock(&nd.path.dentry->d_inode->i_mutex); path_put(&nd.path); return d; } *path = nd.path; return d; |
5590ff0d5 [PATCH] vfs: *at ... |
1942 |
} |
d18114657 [PATCH] new helpe... |
1943 1944 1945 1946 1947 1948 1949 1950 |
int kern_path(const char *name, unsigned int flags, struct path *path) { struct nameidata nd; int res = do_path_lookup(AT_FDCWD, name, flags, &nd); if (!res) *path = nd.path; return res; } |
4d3595073 namei.c: move EXP... |
1951 |
EXPORT_SYMBOL(kern_path); |
d18114657 [PATCH] new helpe... |
1952 |
|
16f182002 fs: introduce vfs... |
1953 1954 1955 1956 1957 1958 |
/** * vfs_path_lookup - lookup a file path relative to a dentry-vfsmount pair * @dentry: pointer to dentry of the base directory * @mnt: pointer to vfs mount of the base directory * @name: pointer to file name * @flags: lookup flags |
e0a012493 switch vfs_path_l... |
1959 |
* @path: pointer to struct path to fill |
16f182002 fs: introduce vfs... |
1960 1961 1962 |
*/ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt, const char *name, unsigned int flags, |
e0a012493 switch vfs_path_l... |
1963 |
struct path *path) |
16f182002 fs: introduce vfs... |
1964 |
{ |
e0a012493 switch vfs_path_l... |
1965 1966 1967 1968 1969 |
struct nameidata nd; int err; nd.root.dentry = dentry; nd.root.mnt = mnt; BUG_ON(flags & LOOKUP_PARENT); |
5b6ca027d reduce vfs_path_l... |
1970 |
/* the first argument of do_path_lookup() is ignored with LOOKUP_ROOT */ |
e0a012493 switch vfs_path_l... |
1971 1972 1973 1974 |
err = do_path_lookup(AT_FDCWD, name, flags | LOOKUP_ROOT, &nd); if (!err) *path = nd.path; return err; |
16f182002 fs: introduce vfs... |
1975 |
} |
4d3595073 namei.c: move EXP... |
1976 |
EXPORT_SYMBOL(vfs_path_lookup); |
16f182002 fs: introduce vfs... |
1977 |
|
057f6c019 security: prevent... |
1978 1979 1980 1981 1982 |
/* * Restricted form of lookup. Doesn't follow links, single-component only, * needs parent already locked. Doesn't follow mounts. * SMP-safe. */ |
eead19115 partially fix up ... |
1983 |
static struct dentry *lookup_hash(struct nameidata *nd) |
057f6c019 security: prevent... |
1984 |
{ |
72bd866a0 fs/namei.c: don't... |
1985 |
return __lookup_hash(&nd->last, nd->path.dentry, nd->flags); |
1da177e4c Linux-2.6.12-rc2 |
1986 |
} |
eead19115 partially fix up ... |
1987 |
/** |
a6b91919e fs: fix kernel-do... |
1988 |
* lookup_one_len - filesystem helper to lookup single pathname component |
eead19115 partially fix up ... |
1989 1990 1991 1992 |
* @name: pathname component to lookup * @base: base directory to lookup from * @len: maximum length @len should be interpreted to * |
a6b91919e fs: fix kernel-do... |
1993 1994 |
* Note that this routine is purely a helper for filesystem usage and should * not be called by generic code. Also note that by using this function the |
eead19115 partially fix up ... |
1995 1996 1997 |
* nameidata argument is passed to the filesystem methods and a filesystem * using this helper needs to be prepared for that. */ |
057f6c019 security: prevent... |
1998 1999 |
struct dentry *lookup_one_len(const char *name, struct dentry *base, int len) { |
057f6c019 security: prevent... |
2000 |
struct qstr this; |
6a96ba544 kill __lookup_one... |
2001 |
unsigned int c; |
cda309de2 vfs: move MAY_EXE... |
2002 |
int err; |
057f6c019 security: prevent... |
2003 |
|
2f9092e10 Fix i_mutex vs. r... |
2004 |
WARN_ON_ONCE(!mutex_is_locked(&base->d_inode->i_mutex)); |
6a96ba544 kill __lookup_one... |
2005 2006 |
this.name = name; this.len = len; |
0145acc20 vfs: uninline ful... |
2007 |
this.hash = full_name_hash(name, len); |
6a96ba544 kill __lookup_one... |
2008 2009 |
if (!len) return ERR_PTR(-EACCES); |
21d8a15ac lookup_one_len: d... |
2010 2011 2012 2013 |
if (unlikely(name[0] == '.')) { if (len < 2 || (len == 2 && name[1] == '.')) return ERR_PTR(-EACCES); } |
6a96ba544 kill __lookup_one... |
2014 2015 2016 2017 |
while (len--) { c = *(const unsigned char *)name++; if (c == '/' || c == '\0') return ERR_PTR(-EACCES); |
6a96ba544 kill __lookup_one... |
2018 |
} |
5a202bcd7 sanitize pathname... |
2019 2020 2021 2022 2023 |
/* * See if the low-level filesystem might want * to use its own hash.. */ if (base->d_flags & DCACHE_OP_HASH) { |
da53be12b Don't pass inode ... |
2024 |
int err = base->d_op->d_hash(base, &this); |
5a202bcd7 sanitize pathname... |
2025 2026 2027 |
if (err < 0) return ERR_PTR(err); } |
eead19115 partially fix up ... |
2028 |
|
cda309de2 vfs: move MAY_EXE... |
2029 2030 2031 |
err = inode_permission(base->d_inode, MAY_EXEC); if (err) return ERR_PTR(err); |
72bd866a0 fs/namei.c: don't... |
2032 |
return __lookup_hash(&this, base, 0); |
057f6c019 security: prevent... |
2033 |
} |
4d3595073 namei.c: move EXP... |
2034 |
EXPORT_SYMBOL(lookup_one_len); |
057f6c019 security: prevent... |
2035 |
|
1fa1e7f61 readlinkat: ensur... |
2036 2037 |
int user_path_at_empty(int dfd, const char __user *name, unsigned flags, struct path *path, int *empty) |
1da177e4c Linux-2.6.12-rc2 |
2038 |
{ |
2d8f30380 [PATCH] sanitize ... |
2039 |
struct nameidata nd; |
91a27b2a7 vfs: define struc... |
2040 |
struct filename *tmp = getname_flags(name, flags, empty); |
1da177e4c Linux-2.6.12-rc2 |
2041 |
int err = PTR_ERR(tmp); |
1da177e4c Linux-2.6.12-rc2 |
2042 |
if (!IS_ERR(tmp)) { |
2d8f30380 [PATCH] sanitize ... |
2043 2044 |
BUG_ON(flags & LOOKUP_PARENT); |
873f1eedc vfs: turn do_path... |
2045 |
err = filename_lookup(dfd, tmp, flags, &nd); |
1da177e4c Linux-2.6.12-rc2 |
2046 |
putname(tmp); |
2d8f30380 [PATCH] sanitize ... |
2047 2048 |
if (!err) *path = nd.path; |
1da177e4c Linux-2.6.12-rc2 |
2049 2050 2051 |
} return err; } |
1fa1e7f61 readlinkat: ensur... |
2052 2053 2054 |
int user_path_at(int dfd, const char __user *name, unsigned flags, struct path *path) { |
f7493e5d9 vfs: tidy up spar... |
2055 |
return user_path_at_empty(dfd, name, flags, path, NULL); |
1fa1e7f61 readlinkat: ensur... |
2056 |
} |
4d3595073 namei.c: move EXP... |
2057 |
EXPORT_SYMBOL(user_path_at); |
1fa1e7f61 readlinkat: ensur... |
2058 |
|
873f1eedc vfs: turn do_path... |
2059 2060 2061 2062 2063 2064 |
/* * NB: most callers don't do anything directly with the reference to the * to struct filename, but the nd->last pointer points into the name string * allocated by getname. So we must hold the reference to it until all * path-walking is complete. */ |
91a27b2a7 vfs: define struc... |
2065 |
static struct filename * |
9e790bd65 vfs: add a flags ... |
2066 2067 |
user_path_parent(int dfd, const char __user *path, struct nameidata *nd, unsigned int flags) |
2ad94ae65 [PATCH] new (loca... |
2068 |
{ |
91a27b2a7 vfs: define struc... |
2069 |
struct filename *s = getname(path); |
2ad94ae65 [PATCH] new (loca... |
2070 |
int error; |
9e790bd65 vfs: add a flags ... |
2071 2072 |
/* only LOOKUP_REVAL is allowed in extra flags */ flags &= LOOKUP_REVAL; |
2ad94ae65 [PATCH] new (loca... |
2073 |
if (IS_ERR(s)) |
91a27b2a7 vfs: define struc... |
2074 |
return s; |
2ad94ae65 [PATCH] new (loca... |
2075 |
|
9e790bd65 vfs: add a flags ... |
2076 |
error = filename_lookup(dfd, s, flags | LOOKUP_PARENT, nd); |
91a27b2a7 vfs: define struc... |
2077 |
if (error) { |
2ad94ae65 [PATCH] new (loca... |
2078 |
putname(s); |
91a27b2a7 vfs: define struc... |
2079 2080 |
return ERR_PTR(error); } |
2ad94ae65 [PATCH] new (loca... |
2081 |
|
91a27b2a7 vfs: define struc... |
2082 |
return s; |
2ad94ae65 [PATCH] new (loca... |
2083 |
} |
8033426e6 vfs: allow umount... |
2084 |
/** |
197df04c7 rename user_path_... |
2085 |
* mountpoint_last - look up last component for umount |
8033426e6 vfs: allow umount... |
2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 |
* @nd: pathwalk nameidata - currently pointing at parent directory of "last" * @path: pointer to container for result * * This is a special lookup_last function just for umount. In this case, we * need to resolve the path without doing any revalidation. * * The nameidata should be the result of doing a LOOKUP_PARENT pathwalk. Since * mountpoints are always pinned in the dcache, their ancestors are too. Thus, * in almost all cases, this lookup will be served out of the dcache. The only * cases where it won't are if nd->last refers to a symlink or the path is * bogus and it doesn't exist. * * Returns: * -error: if there was an error during lookup. This includes -ENOENT if the * lookup found a negative dentry. The nd->path reference will also be * put in this case. * * 0: if we successfully resolved nd->path and found it to not to be a * symlink that needs to be followed. "path" will also be populated. * The nd->path reference will also be put. * * 1: if we successfully resolved nd->last and found it to be a symlink * that needs to be followed. "path" will be populated with the path * to the link, and nd->path will *not* be put. */ static int |
197df04c7 rename user_path_... |
2112 |
mountpoint_last(struct nameidata *nd, struct path *path) |
8033426e6 vfs: allow umount... |
2113 2114 2115 2116 |
{ int error = 0; struct dentry *dentry; struct dentry *dir = nd->path.dentry; |
35759521e take unlazy_walk(... |
2117 2118 2119 2120 2121 2122 |
/* If we're in rcuwalk, drop out of it to handle last component */ if (nd->flags & LOOKUP_RCU) { if (unlazy_walk(nd, NULL)) { error = -ECHILD; goto out; } |
8033426e6 vfs: allow umount... |
2123 2124 2125 2126 2127 2128 |
} nd->flags &= ~LOOKUP_PARENT; if (unlikely(nd->last_type != LAST_NORM)) { error = handle_dots(nd, nd->last_type); |
35759521e take unlazy_walk(... |
2129 2130 2131 2132 |
if (error) goto out; dentry = dget(nd->path.dentry); goto done; |
8033426e6 vfs: allow umount... |
2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 |
} mutex_lock(&dir->d_inode->i_mutex); dentry = d_lookup(dir, &nd->last); if (!dentry) { /* * No cached dentry. Mounted dentries are pinned in the cache, * so that means that this dentry is probably a symlink or the * path doesn't actually point to a mounted dentry. */ dentry = d_alloc(dir, &nd->last); if (!dentry) { error = -ENOMEM; |
bcceeeba9 Add missing unloc... |
2146 |
mutex_unlock(&dir->d_inode->i_mutex); |
35759521e take unlazy_walk(... |
2147 |
goto out; |
8033426e6 vfs: allow umount... |
2148 |
} |
35759521e take unlazy_walk(... |
2149 2150 |
dentry = lookup_real(dir->d_inode, dentry, nd->flags); error = PTR_ERR(dentry); |
bcceeeba9 Add missing unloc... |
2151 2152 |
if (IS_ERR(dentry)) { mutex_unlock(&dir->d_inode->i_mutex); |
35759521e take unlazy_walk(... |
2153 |
goto out; |
bcceeeba9 Add missing unloc... |
2154 |
} |
8033426e6 vfs: allow umount... |
2155 2156 |
} mutex_unlock(&dir->d_inode->i_mutex); |
35759521e take unlazy_walk(... |
2157 |
done: |
22213318a fix races between... |
2158 |
if (!dentry->d_inode || d_is_negative(dentry)) { |
35759521e take unlazy_walk(... |
2159 2160 2161 |
error = -ENOENT; dput(dentry); goto out; |
8033426e6 vfs: allow umount... |
2162 |
} |
35759521e take unlazy_walk(... |
2163 |
path->dentry = dentry; |
295dc39d9 fs: umount on sym... |
2164 |
path->mnt = nd->path.mnt; |
b18825a7c VFS: Put a small ... |
2165 |
if (should_follow_link(dentry, nd->flags & LOOKUP_FOLLOW)) |
35759521e take unlazy_walk(... |
2166 |
return 1; |
295dc39d9 fs: umount on sym... |
2167 |
mntget(path->mnt); |
35759521e take unlazy_walk(... |
2168 2169 2170 |
follow_mount(path); error = 0; out: |
8033426e6 vfs: allow umount... |
2171 2172 2173 2174 2175 |
terminate_walk(nd); return error; } /** |
197df04c7 rename user_path_... |
2176 |
* path_mountpoint - look up a path to be umounted |
8033426e6 vfs: allow umount... |
2177 2178 |
* @dfd: directory file descriptor to start walk from * @name: full pathname to walk |
606d6fe3f fs/namei.c: fix n... |
2179 |
* @path: pointer to container for result |
8033426e6 vfs: allow umount... |
2180 |
* @flags: lookup flags |
8033426e6 vfs: allow umount... |
2181 2182 |
* * Look up the given name, but don't attempt to revalidate the last component. |
606d6fe3f fs/namei.c: fix n... |
2183 |
* Returns 0 and "path" will be valid on success; Returns error otherwise. |
8033426e6 vfs: allow umount... |
2184 2185 |
*/ static int |
197df04c7 rename user_path_... |
2186 |
path_mountpoint(int dfd, const char *name, struct path *path, unsigned int flags) |
8033426e6 vfs: allow umount... |
2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 |
{ struct file *base = NULL; struct nameidata nd; int err; err = path_init(dfd, name, flags | LOOKUP_PARENT, &nd, &base); if (unlikely(err)) return err; current->total_link_count = 0; err = link_path_walk(name, &nd); if (err) goto out; |
197df04c7 rename user_path_... |
2200 |
err = mountpoint_last(&nd, path); |
8033426e6 vfs: allow umount... |
2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 |
while (err > 0) { void *cookie; struct path link = *path; err = may_follow_link(&link, &nd); if (unlikely(err)) break; nd.flags |= LOOKUP_PARENT; err = follow_link(&link, &nd, &cookie); if (err) break; |
197df04c7 rename user_path_... |
2211 |
err = mountpoint_last(&nd, path); |
8033426e6 vfs: allow umount... |
2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 |
put_link(&nd, &link, cookie); } out: if (base) fput(base); if (nd.root.mnt && !(nd.flags & LOOKUP_ROOT)) path_put(&nd.root); return err; } |
2d8646510 introduce kern_pa... |
2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 |
static int filename_mountpoint(int dfd, struct filename *s, struct path *path, unsigned int flags) { int error = path_mountpoint(dfd, s->name, path, flags | LOOKUP_RCU); if (unlikely(error == -ECHILD)) error = path_mountpoint(dfd, s->name, path, flags); if (unlikely(error == -ESTALE)) error = path_mountpoint(dfd, s->name, path, flags | LOOKUP_REVAL); if (likely(!error)) audit_inode(s, path->dentry, 0); return error; } |
8033426e6 vfs: allow umount... |
2236 |
/** |
197df04c7 rename user_path_... |
2237 |
* user_path_mountpoint_at - lookup a path from userland in order to umount it |
8033426e6 vfs: allow umount... |
2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 |
* @dfd: directory file descriptor * @name: pathname from userland * @flags: lookup flags * @path: pointer to container to hold result * * A umount is a special case for path walking. We're not actually interested * in the inode in this situation, and ESTALE errors can be a problem. We * simply want track down the dentry and vfsmount attached at the mountpoint * and avoid revalidating the last component. * * Returns 0 and populates "path" on success. */ int |
197df04c7 rename user_path_... |
2251 |
user_path_mountpoint_at(int dfd, const char __user *name, unsigned int flags, |
8033426e6 vfs: allow umount... |
2252 2253 2254 2255 |
struct path *path) { struct filename *s = getname(name); int error; |
8033426e6 vfs: allow umount... |
2256 2257 |
if (IS_ERR(s)) return PTR_ERR(s); |
2d8646510 introduce kern_pa... |
2258 |
error = filename_mountpoint(dfd, s, path, flags); |
8033426e6 vfs: allow umount... |
2259 2260 2261 |
putname(s); return error; } |
2d8646510 introduce kern_pa... |
2262 2263 2264 2265 2266 2267 2268 2269 |
int kern_path_mountpoint(int dfd, const char *name, struct path *path, unsigned int flags) { struct filename s = {.name = name}; return filename_mountpoint(dfd, &s, path, flags); } EXPORT_SYMBOL(kern_path_mountpoint); |
1da177e4c Linux-2.6.12-rc2 |
2270 2271 2272 2273 2274 2275 |
/* * It's inline, so penalty for filesystems that don't use sticky bit is * minimal. */ static inline int check_sticky(struct inode *dir, struct inode *inode) { |
8e96e3b7b userns: Use uid_e... |
2276 |
kuid_t fsuid = current_fsuid(); |
da9592ede CRED: Wrap task c... |
2277 |
|
1da177e4c Linux-2.6.12-rc2 |
2278 2279 |
if (!(dir->i_mode & S_ISVTX)) return 0; |
8e96e3b7b userns: Use uid_e... |
2280 |
if (uid_eq(inode->i_uid, fsuid)) |
1da177e4c Linux-2.6.12-rc2 |
2281 |
return 0; |
8e96e3b7b userns: Use uid_e... |
2282 |
if (uid_eq(dir->i_uid, fsuid)) |
1da177e4c Linux-2.6.12-rc2 |
2283 |
return 0; |
23adbe12e fs,userns: Change... |
2284 |
return !capable_wrt_inode_uidgid(inode, CAP_FOWNER); |
1da177e4c Linux-2.6.12-rc2 |
2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 |
} /* * Check whether we can remove a link victim from directory dir, check * whether the type of victim is right. * 1. We can't do it if dir is read-only (done in permission()) * 2. We should have write and exec permissions on dir * 3. We can't remove anything from append-only dir * 4. We can't do anything with immutable dir (done in permission()) * 5. If the sticky bit on dir is set we should either * a. be owner of dir, or * b. be owner of victim, or * c. have CAP_FOWNER capability * 6. If the victim is append-only or immutable we can't do antyhing with * links pointing to it. * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR. * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR. * 9. We can't remove a root or mountpoint. * 10. We don't allow removal of NFS sillyrenamed files; it's handled by * nfs_async_unlink(). */ |
b18825a7c VFS: Put a small ... |
2306 |
static int may_delete(struct inode *dir, struct dentry *victim, bool isdir) |
1da177e4c Linux-2.6.12-rc2 |
2307 |
{ |
b18825a7c VFS: Put a small ... |
2308 |
struct inode *inode = victim->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
2309 |
int error; |
b18825a7c VFS: Put a small ... |
2310 |
if (d_is_negative(victim)) |
1da177e4c Linux-2.6.12-rc2 |
2311 |
return -ENOENT; |
b18825a7c VFS: Put a small ... |
2312 |
BUG_ON(!inode); |
1da177e4c Linux-2.6.12-rc2 |
2313 2314 |
BUG_ON(victim->d_parent->d_inode != dir); |
4fa6b5ecb audit: overhaul _... |
2315 |
audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE); |
1da177e4c Linux-2.6.12-rc2 |
2316 |
|
f419a2e3b [PATCH] kill name... |
2317 |
error = inode_permission(dir, MAY_WRITE | MAY_EXEC); |
1da177e4c Linux-2.6.12-rc2 |
2318 2319 2320 2321 |
if (error) return error; if (IS_APPEND(dir)) return -EPERM; |
b18825a7c VFS: Put a small ... |
2322 2323 2324 |
if (check_sticky(dir, inode) || IS_APPEND(inode) || IS_IMMUTABLE(inode) || IS_SWAPFILE(inode)) |
1da177e4c Linux-2.6.12-rc2 |
2325 2326 |
return -EPERM; if (isdir) { |
44b1d5304 vfs: add d_is_dir() |
2327 |
if (!d_is_dir(victim)) |
1da177e4c Linux-2.6.12-rc2 |
2328 2329 2330 |
return -ENOTDIR; if (IS_ROOT(victim)) return -EBUSY; |
44b1d5304 vfs: add d_is_dir() |
2331 |
} else if (d_is_dir(victim)) |
1da177e4c Linux-2.6.12-rc2 |
2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 |
return -EISDIR; if (IS_DEADDIR(dir)) return -ENOENT; if (victim->d_flags & DCACHE_NFSFS_RENAMED) return -EBUSY; return 0; } /* Check whether we can create an object with dentry child in directory * dir. * 1. We can't do it if child already exists (open has special treatment for * this case, but since we are inlined it's OK) * 2. We can't do it if dir is read-only (done in permission()) * 3. We should have write and exec permissions on dir * 4. We can't do it if dir is immutable (done in permission()) */ |
a95164d97 [patch 3/4] vfs: ... |
2348 |
static inline int may_create(struct inode *dir, struct dentry *child) |
1da177e4c Linux-2.6.12-rc2 |
2349 |
{ |
14e972b45 audit: add child ... |
2350 |
audit_inode_child(dir, child, AUDIT_TYPE_CHILD_CREATE); |
1da177e4c Linux-2.6.12-rc2 |
2351 2352 2353 2354 |
if (child->d_inode) return -EEXIST; if (IS_DEADDIR(dir)) return -ENOENT; |
f419a2e3b [PATCH] kill name... |
2355 |
return inode_permission(dir, MAY_WRITE | MAY_EXEC); |
1da177e4c Linux-2.6.12-rc2 |
2356 |
} |
1da177e4c Linux-2.6.12-rc2 |
2357 2358 2359 2360 2361 2362 2363 2364 |
/* * p1 and p2 should be directories on the same fs. */ struct dentry *lock_rename(struct dentry *p1, struct dentry *p2) { struct dentry *p; if (p1 == p2) { |
f2eace23e [PATCH] lockdep: ... |
2365 |
mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT); |
1da177e4c Linux-2.6.12-rc2 |
2366 2367 |
return NULL; } |
a11f3a057 [PATCH] sem2mutex... |
2368 |
mutex_lock(&p1->d_inode->i_sb->s_vfs_rename_mutex); |
1da177e4c Linux-2.6.12-rc2 |
2369 |
|
e2761a116 [PATCH vfs-2.6 2/... |
2370 2371 2372 2373 2374 |
p = d_ancestor(p2, p1); if (p) { mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_PARENT); mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_CHILD); return p; |
1da177e4c Linux-2.6.12-rc2 |
2375 |
} |
e2761a116 [PATCH vfs-2.6 2/... |
2376 2377 2378 2379 2380 |
p = d_ancestor(p1, p2); if (p) { mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT); mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD); return p; |
1da177e4c Linux-2.6.12-rc2 |
2381 |
} |
f2eace23e [PATCH] lockdep: ... |
2382 2383 |
mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT); mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD); |
1da177e4c Linux-2.6.12-rc2 |
2384 2385 |
return NULL; } |
4d3595073 namei.c: move EXP... |
2386 |
EXPORT_SYMBOL(lock_rename); |
1da177e4c Linux-2.6.12-rc2 |
2387 2388 2389 |
void unlock_rename(struct dentry *p1, struct dentry *p2) { |
1b1dcc1b5 [PATCH] mutex sub... |
2390 |
mutex_unlock(&p1->d_inode->i_mutex); |
1da177e4c Linux-2.6.12-rc2 |
2391 |
if (p1 != p2) { |
1b1dcc1b5 [PATCH] mutex sub... |
2392 |
mutex_unlock(&p2->d_inode->i_mutex); |
a11f3a057 [PATCH] sem2mutex... |
2393 |
mutex_unlock(&p1->d_inode->i_sb->s_vfs_rename_mutex); |
1da177e4c Linux-2.6.12-rc2 |
2394 2395 |
} } |
4d3595073 namei.c: move EXP... |
2396 |
EXPORT_SYMBOL(unlock_rename); |
1da177e4c Linux-2.6.12-rc2 |
2397 |
|
4acdaf27e switch ->create()... |
2398 |
int vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, |
312b63fba don't pass nameid... |
2399 |
bool want_excl) |
1da177e4c Linux-2.6.12-rc2 |
2400 |
{ |
a95164d97 [patch 3/4] vfs: ... |
2401 |
int error = may_create(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
2402 2403 |
if (error) return error; |
acfa4380e inode->i_op is ne... |
2404 |
if (!dir->i_op->create) |
1da177e4c Linux-2.6.12-rc2 |
2405 2406 2407 2408 2409 2410 |
return -EACCES; /* shouldn't it be ENOSYS? */ mode &= S_IALLUGO; mode |= S_IFREG; error = security_inode_create(dir, dentry, mode); if (error) return error; |
312b63fba don't pass nameid... |
2411 |
error = dir->i_op->create(dir, dentry, mode, want_excl); |
a74574aaf [PATCH] Remove se... |
2412 |
if (!error) |
f38aa9422 [PATCH] Pass dent... |
2413 |
fsnotify_create(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
2414 2415 |
return error; } |
4d3595073 namei.c: move EXP... |
2416 |
EXPORT_SYMBOL(vfs_create); |
1da177e4c Linux-2.6.12-rc2 |
2417 |
|
73d049a40 open-style analog... |
2418 |
static int may_open(struct path *path, int acc_mode, int flag) |
1da177e4c Linux-2.6.12-rc2 |
2419 |
{ |
3fb64190a pass a struct pat... |
2420 |
struct dentry *dentry = path->dentry; |
1da177e4c Linux-2.6.12-rc2 |
2421 2422 |
struct inode *inode = dentry->d_inode; int error; |
bcda76524 Allow O_PATH for ... |
2423 2424 2425 |
/* O_PATH? */ if (!acc_mode) return 0; |
1da177e4c Linux-2.6.12-rc2 |
2426 2427 |
if (!inode) return -ENOENT; |
c8fe8f30c cleanup may_open |
2428 2429 |
switch (inode->i_mode & S_IFMT) { case S_IFLNK: |
1da177e4c Linux-2.6.12-rc2 |
2430 |
return -ELOOP; |
c8fe8f30c cleanup may_open |
2431 2432 2433 2434 2435 2436 |
case S_IFDIR: if (acc_mode & MAY_WRITE) return -EISDIR; break; case S_IFBLK: case S_IFCHR: |
3fb64190a pass a struct pat... |
2437 |
if (path->mnt->mnt_flags & MNT_NODEV) |
1da177e4c Linux-2.6.12-rc2 |
2438 |
return -EACCES; |
c8fe8f30c cleanup may_open |
2439 2440 2441 |
/*FALLTHRU*/ case S_IFIFO: case S_IFSOCK: |
1da177e4c Linux-2.6.12-rc2 |
2442 |
flag &= ~O_TRUNC; |
c8fe8f30c cleanup may_open |
2443 |
break; |
4a3fd211c [PATCH] r/o bind ... |
2444 |
} |
b41572e92 r/o bind mounts: ... |
2445 |
|
3fb64190a pass a struct pat... |
2446 |
error = inode_permission(inode, acc_mode); |
b41572e92 r/o bind mounts: ... |
2447 2448 |
if (error) return error; |
6146f0d5e integrity: IMA hooks |
2449 |
|
1da177e4c Linux-2.6.12-rc2 |
2450 2451 2452 2453 |
/* * An append-only file must be opened in append mode for writing. */ if (IS_APPEND(inode)) { |
8737c9305 Switch may_open()... |
2454 |
if ((flag & O_ACCMODE) != O_RDONLY && !(flag & O_APPEND)) |
7715b5212 O_TRUNC open shou... |
2455 |
return -EPERM; |
1da177e4c Linux-2.6.12-rc2 |
2456 |
if (flag & O_TRUNC) |
7715b5212 O_TRUNC open shou... |
2457 |
return -EPERM; |
1da177e4c Linux-2.6.12-rc2 |
2458 2459 2460 |
} /* O_NOATIME can only be set by the owner or superuser */ |
2e1496707 userns: rename is... |
2461 |
if (flag & O_NOATIME && !inode_owner_or_capable(inode)) |
7715b5212 O_TRUNC open shou... |
2462 |
return -EPERM; |
1da177e4c Linux-2.6.12-rc2 |
2463 |
|
f3c7691e8 leases: fix write... |
2464 |
return 0; |
7715b5212 O_TRUNC open shou... |
2465 |
} |
1da177e4c Linux-2.6.12-rc2 |
2466 |
|
e1181ee65 vfs: pass struct ... |
2467 |
static int handle_truncate(struct file *filp) |
7715b5212 O_TRUNC open shou... |
2468 |
{ |
e1181ee65 vfs: pass struct ... |
2469 |
struct path *path = &filp->f_path; |
7715b5212 O_TRUNC open shou... |
2470 2471 2472 2473 2474 2475 2476 |
struct inode *inode = path->dentry->d_inode; int error = get_write_access(inode); if (error) return error; /* * Refuse to truncate files with mandatory locks held on them. */ |
d7a06983a locks: fix locks_... |
2477 |
error = locks_verify_locked(filp); |
7715b5212 O_TRUNC open shou... |
2478 |
if (!error) |
ea0d3ab23 LSM: Remove unuse... |
2479 |
error = security_path_truncate(path); |
7715b5212 O_TRUNC open shou... |
2480 2481 2482 |
if (!error) { error = do_truncate(path->dentry, 0, ATTR_MTIME|ATTR_CTIME|ATTR_OPEN, |
e1181ee65 vfs: pass struct ... |
2483 |
filp); |
7715b5212 O_TRUNC open shou... |
2484 2485 |
} put_write_access(inode); |
acd0c9351 IMA: update ima_c... |
2486 |
return error; |
1da177e4c Linux-2.6.12-rc2 |
2487 |
} |
d57999e15 [PATCH] do namei_... |
2488 2489 |
static inline int open_to_namei_flags(int flag) { |
8a5e929dd don't translitera... |
2490 2491 |
if ((flag & O_ACCMODE) == 3) flag--; |
d57999e15 [PATCH] do namei_... |
2492 2493 |
return flag; } |
d18e9008c vfs: add i_op->at... |
2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 |
static int may_o_create(struct path *dir, struct dentry *dentry, umode_t mode) { int error = security_path_mknod(dir, dentry, mode, 0); if (error) return error; error = inode_permission(dir->dentry->d_inode, MAY_WRITE | MAY_EXEC); if (error) return error; return security_inode_create(dir->dentry->d_inode, dentry, mode); } |
1acf0af9b VFS: Fix the bann... |
2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 |
/* * Attempt to atomically look up, create and open a file from a negative * dentry. * * Returns 0 if successful. The file will have been created and attached to * @file by the filesystem calling finish_open(). * * Returns 1 if the file was looked up only or didn't need creating. The * caller will need to perform the open themselves. @path will have been * updated to point to the new dentry. This may be negative. * * Returns an error code otherwise. */ |
2675a4eb6 fs/namei.c: get d... |
2519 2520 2521 |
static int atomic_open(struct nameidata *nd, struct dentry *dentry, struct path *path, struct file *file, const struct open_flags *op, |
64894cf84 simplify lookup_o... |
2522 |
bool got_write, bool need_lookup, |
2675a4eb6 fs/namei.c: get d... |
2523 |
int *opened) |
d18e9008c vfs: add i_op->at... |
2524 2525 2526 2527 2528 2529 |
{ struct inode *dir = nd->path.dentry->d_inode; unsigned open_flag = open_to_namei_flags(op->open_flag); umode_t mode; int error; int acc_mode; |
d18e9008c vfs: add i_op->at... |
2530 2531 |
int create_error = 0; struct dentry *const DENTRY_NOT_SET = (void *) -1UL; |
116cc0225 vfs: don't set FI... |
2532 |
bool excl; |
d18e9008c vfs: add i_op->at... |
2533 2534 2535 2536 2537 |
BUG_ON(dentry->d_inode); /* Don't create child dentry for a dead directory. */ if (unlikely(IS_DEADDIR(dir))) { |
2675a4eb6 fs/namei.c: get d... |
2538 |
error = -ENOENT; |
d18e9008c vfs: add i_op->at... |
2539 2540 |
goto out; } |
62b259d8b vfs: atomic_open(... |
2541 |
mode = op->mode; |
d18e9008c vfs: add i_op->at... |
2542 2543 |
if ((open_flag & O_CREAT) && !IS_POSIXACL(dir)) mode &= ~current_umask(); |
116cc0225 vfs: don't set FI... |
2544 2545 |
excl = (open_flag & (O_EXCL | O_CREAT)) == (O_EXCL | O_CREAT); if (excl) |
d18e9008c vfs: add i_op->at... |
2546 |
open_flag &= ~O_TRUNC; |
d18e9008c vfs: add i_op->at... |
2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 |
/* * Checking write permission is tricky, bacuse we don't know if we are * going to actually need it: O_CREAT opens should work as long as the * file exists. But checking existence breaks atomicity. The trick is * to check access and if not granted clear O_CREAT from the flags. * * Another problem is returing the "right" error value (e.g. for an * O_EXCL open we want to return EEXIST not EROFS). */ |
64894cf84 simplify lookup_o... |
2557 2558 2559 |
if (((open_flag & (O_CREAT | O_TRUNC)) || (open_flag & O_ACCMODE) != O_RDONLY) && unlikely(!got_write)) { if (!(open_flag & O_CREAT)) { |
d18e9008c vfs: add i_op->at... |
2560 2561 2562 2563 2564 2565 2566 |
/* * No O_CREATE -> atomicity not a requirement -> fall * back to lookup + open */ goto no_open; } else if (open_flag & (O_EXCL | O_TRUNC)) { /* Fall back and fail with the right error */ |
64894cf84 simplify lookup_o... |
2567 |
create_error = -EROFS; |
d18e9008c vfs: add i_op->at... |
2568 2569 2570 |
goto no_open; } else { /* No side effects, safe to clear O_CREAT */ |
64894cf84 simplify lookup_o... |
2571 |
create_error = -EROFS; |
d18e9008c vfs: add i_op->at... |
2572 2573 2574 2575 2576 |
open_flag &= ~O_CREAT; } } if (open_flag & O_CREAT) { |
38227f78a vfs: pass right c... |
2577 |
error = may_o_create(&nd->path, dentry, mode); |
d18e9008c vfs: add i_op->at... |
2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 |
if (error) { create_error = error; if (open_flag & O_EXCL) goto no_open; open_flag &= ~O_CREAT; } } if (nd->flags & LOOKUP_DIRECTORY) open_flag |= O_DIRECTORY; |
30d904947 kill struct opendata |
2588 2589 2590 |
file->f_path.dentry = DENTRY_NOT_SET; file->f_path.mnt = nd->path.mnt; error = dir->i_op->atomic_open(dir, dentry, file, open_flag, mode, |
47237687d ->atomic_open() p... |
2591 |
opened); |
d95852777 make ->atomic_ope... |
2592 |
if (error < 0) { |
d95852777 make ->atomic_ope... |
2593 2594 |
if (create_error && error == -ENOENT) error = create_error; |
d18e9008c vfs: add i_op->at... |
2595 2596 |
goto out; } |
d95852777 make ->atomic_ope... |
2597 |
if (error) { /* returned 1, that is */ |
30d904947 kill struct opendata |
2598 |
if (WARN_ON(file->f_path.dentry == DENTRY_NOT_SET)) { |
2675a4eb6 fs/namei.c: get d... |
2599 |
error = -EIO; |
d18e9008c vfs: add i_op->at... |
2600 2601 |
goto out; } |
30d904947 kill struct opendata |
2602 |
if (file->f_path.dentry) { |
d18e9008c vfs: add i_op->at... |
2603 |
dput(dentry); |
30d904947 kill struct opendata |
2604 |
dentry = file->f_path.dentry; |
d18e9008c vfs: add i_op->at... |
2605 |
} |
03da633aa atomic_open: take... |
2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 |
if (*opened & FILE_CREATED) fsnotify_create(dir, dentry); if (!dentry->d_inode) { WARN_ON(*opened & FILE_CREATED); if (create_error) { error = create_error; goto out; } } else { if (excl && !(*opened & FILE_CREATED)) { error = -EEXIST; goto out; } |
62b2ce964 vfs: fix propagat... |
2619 |
} |
d18e9008c vfs: add i_op->at... |
2620 2621 2622 2623 2624 2625 2626 |
goto looked_up; } /* * We didn't have the inode before the open, so check open permission * here. */ |
03da633aa atomic_open: take... |
2627 2628 2629 2630 2631 2632 |
acc_mode = op->acc_mode; if (*opened & FILE_CREATED) { WARN_ON(!(open_flag & O_CREAT)); fsnotify_create(dir, dentry); acc_mode = MAY_OPEN; } |
2675a4eb6 fs/namei.c: get d... |
2633 2634 2635 |
error = may_open(&file->f_path, acc_mode, open_flag); if (error) fput(file); |
d18e9008c vfs: add i_op->at... |
2636 2637 2638 |
out: dput(dentry); |
2675a4eb6 fs/namei.c: get d... |
2639 |
return error; |
d18e9008c vfs: add i_op->at... |
2640 |
|
d18e9008c vfs: add i_op->at... |
2641 2642 |
no_open: if (need_lookup) { |
72bd866a0 fs/namei.c: don't... |
2643 |
dentry = lookup_real(dir, dentry, nd->flags); |
d18e9008c vfs: add i_op->at... |
2644 |
if (IS_ERR(dentry)) |
2675a4eb6 fs/namei.c: get d... |
2645 |
return PTR_ERR(dentry); |
d18e9008c vfs: add i_op->at... |
2646 2647 2648 |
if (create_error) { int open_flag = op->open_flag; |
2675a4eb6 fs/namei.c: get d... |
2649 |
error = create_error; |
d18e9008c vfs: add i_op->at... |
2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 |
if ((open_flag & O_EXCL)) { if (!dentry->d_inode) goto out; } else if (!dentry->d_inode) { goto out; } else if ((open_flag & O_TRUNC) && S_ISREG(dentry->d_inode->i_mode)) { goto out; } /* will fail later, go on to get the right error */ } } looked_up: path->dentry = dentry; path->mnt = nd->path.mnt; |
2675a4eb6 fs/namei.c: get d... |
2665 |
return 1; |
d18e9008c vfs: add i_op->at... |
2666 |
} |
31e6b01f4 fs: rcu-walk for ... |
2667 |
/* |
1acf0af9b VFS: Fix the bann... |
2668 |
* Look up and maybe create and open the last component. |
d58ffd35c vfs: add lookup_o... |
2669 2670 2671 |
* * Must be called with i_mutex held on parent. * |
1acf0af9b VFS: Fix the bann... |
2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 |
* Returns 0 if the file was successfully atomically created (if necessary) and * opened. In this case the file will be returned attached to @file. * * Returns 1 if the file was not completely opened at this time, though lookups * and creations will have been performed and the dentry returned in @path will * be positive upon return if O_CREAT was specified. If O_CREAT wasn't * specified then a negative dentry may be returned. * * An error code is returned otherwise. * * FILE_CREATE will be set in @*opened if the dentry was created and will be * cleared otherwise prior to returning. |
d58ffd35c vfs: add lookup_o... |
2684 |
*/ |
2675a4eb6 fs/namei.c: get d... |
2685 2686 2687 |
static int lookup_open(struct nameidata *nd, struct path *path, struct file *file, const struct open_flags *op, |
64894cf84 simplify lookup_o... |
2688 |
bool got_write, int *opened) |
d58ffd35c vfs: add lookup_o... |
2689 2690 |
{ struct dentry *dir = nd->path.dentry; |
54ef48724 vfs: lookup_open(... |
2691 |
struct inode *dir_inode = dir->d_inode; |
d58ffd35c vfs: add lookup_o... |
2692 2693 |
struct dentry *dentry; int error; |
54ef48724 vfs: lookup_open(... |
2694 |
bool need_lookup; |
d58ffd35c vfs: add lookup_o... |
2695 |
|
47237687d ->atomic_open() p... |
2696 |
*opened &= ~FILE_CREATED; |
201f956e4 fs/namei.c: don't... |
2697 |
dentry = lookup_dcache(&nd->last, dir, nd->flags, &need_lookup); |
d58ffd35c vfs: add lookup_o... |
2698 |
if (IS_ERR(dentry)) |
2675a4eb6 fs/namei.c: get d... |
2699 |
return PTR_ERR(dentry); |
d58ffd35c vfs: add lookup_o... |
2700 |
|
d18e9008c vfs: add i_op->at... |
2701 2702 2703 2704 2705 |
/* Cached positive dentry: will open in f_op->open */ if (!need_lookup && dentry->d_inode) goto out_no_open; if ((nd->flags & LOOKUP_OPEN) && dir_inode->i_op->atomic_open) { |
64894cf84 simplify lookup_o... |
2706 |
return atomic_open(nd, dentry, path, file, op, got_write, |
47237687d ->atomic_open() p... |
2707 |
need_lookup, opened); |
d18e9008c vfs: add i_op->at... |
2708 |
} |
54ef48724 vfs: lookup_open(... |
2709 2710 |
if (need_lookup) { BUG_ON(dentry->d_inode); |
72bd866a0 fs/namei.c: don't... |
2711 |
dentry = lookup_real(dir_inode, dentry, nd->flags); |
54ef48724 vfs: lookup_open(... |
2712 |
if (IS_ERR(dentry)) |
2675a4eb6 fs/namei.c: get d... |
2713 |
return PTR_ERR(dentry); |
54ef48724 vfs: lookup_open(... |
2714 |
} |
d58ffd35c vfs: add lookup_o... |
2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 |
/* Negative dentry, just create the file */ if (!dentry->d_inode && (op->open_flag & O_CREAT)) { umode_t mode = op->mode; if (!IS_POSIXACL(dir->d_inode)) mode &= ~current_umask(); /* * This write is needed to ensure that a * rw->ro transition does not occur between * the time when the file is created and when * a permanent write count is taken through |
015c3bbcd vfs: remove open ... |
2725 |
* the 'struct file' in finish_open(). |
d58ffd35c vfs: add lookup_o... |
2726 |
*/ |
64894cf84 simplify lookup_o... |
2727 2728 |
if (!got_write) { error = -EROFS; |
d58ffd35c vfs: add lookup_o... |
2729 |
goto out_dput; |
64894cf84 simplify lookup_o... |
2730 |
} |
47237687d ->atomic_open() p... |
2731 |
*opened |= FILE_CREATED; |
d58ffd35c vfs: add lookup_o... |
2732 2733 2734 |
error = security_path_mknod(&nd->path, dentry, mode, 0); if (error) goto out_dput; |
312b63fba don't pass nameid... |
2735 2736 |
error = vfs_create(dir->d_inode, dentry, mode, nd->flags & LOOKUP_EXCL); |
d58ffd35c vfs: add lookup_o... |
2737 2738 2739 |
if (error) goto out_dput; } |
d18e9008c vfs: add i_op->at... |
2740 |
out_no_open: |
d58ffd35c vfs: add lookup_o... |
2741 2742 |
path->dentry = dentry; path->mnt = nd->path.mnt; |
2675a4eb6 fs/namei.c: get d... |
2743 |
return 1; |
d58ffd35c vfs: add lookup_o... |
2744 2745 2746 |
out_dput: dput(dentry); |
2675a4eb6 fs/namei.c: get d... |
2747 |
return error; |
d58ffd35c vfs: add lookup_o... |
2748 2749 2750 |
} /* |
fe2d35ff0 switch non-create... |
2751 |
* Handle the last step of open() |
31e6b01f4 fs: rcu-walk for ... |
2752 |
*/ |
2675a4eb6 fs/namei.c: get d... |
2753 2754 |
static int do_last(struct nameidata *nd, struct path *path, struct file *file, const struct open_flags *op, |
669abf4e5 vfs: make path_op... |
2755 |
int *opened, struct filename *name) |
fb1cc555d gut do_filp_open(... |
2756 |
{ |
a1e28038d pull the common p... |
2757 |
struct dentry *dir = nd->path.dentry; |
ca344a894 do_last: unify ma... |
2758 |
int open_flag = op->open_flag; |
77d660a8a vfs: do_last(): c... |
2759 |
bool will_truncate = (open_flag & O_TRUNC) != 0; |
64894cf84 simplify lookup_o... |
2760 |
bool got_write = false; |
bcda76524 Allow O_PATH for ... |
2761 |
int acc_mode = op->acc_mode; |
a1eb33153 vfs: do_last(): i... |
2762 |
struct inode *inode; |
77d660a8a vfs: do_last(): c... |
2763 |
bool symlink_ok = false; |
16b1c1cd7 vfs: retry last c... |
2764 2765 |
struct path save_parent = { .dentry = NULL, .mnt = NULL }; bool retried = false; |
16c2cd717 untangle the "nee... |
2766 |
int error; |
1f36f774b Switch !O_CREAT c... |
2767 |
|
c3e380b0b Collect "operatio... |
2768 2769 |
nd->flags &= ~LOOKUP_PARENT; nd->flags |= op->intent; |
bc77daa78 do_last(): fix mi... |
2770 |
if (nd->last_type != LAST_NORM) { |
fe2d35ff0 switch non-create... |
2771 2772 |
error = handle_dots(nd, nd->last_type); if (error) |
2675a4eb6 fs/namei.c: get d... |
2773 |
return error; |
e83db1672 vfs: do_last(): c... |
2774 |
goto finish_open; |
1f36f774b Switch !O_CREAT c... |
2775 |
} |
67ee3ad21 Pull handling of ... |
2776 |
|
ca344a894 do_last: unify ma... |
2777 |
if (!(open_flag & O_CREAT)) { |
fe2d35ff0 switch non-create... |
2778 2779 |
if (nd->last.name[nd->last.len]) nd->flags |= LOOKUP_FOLLOW | LOOKUP_DIRECTORY; |
bcda76524 Allow O_PATH for ... |
2780 |
if (open_flag & O_PATH && !(nd->flags & LOOKUP_FOLLOW)) |
77d660a8a vfs: do_last(): c... |
2781 |
symlink_ok = true; |
fe2d35ff0 switch non-create... |
2782 |
/* we _can_ be in RCU mode here */ |
e97cdc87b lookup_fast: get ... |
2783 |
error = lookup_fast(nd, path, &inode); |
715748654 vfs: do_last(): c... |
2784 2785 2786 2787 |
if (likely(!error)) goto finish_lookup; if (error < 0) |
2675a4eb6 fs/namei.c: get d... |
2788 |
goto out; |
715748654 vfs: do_last(): c... |
2789 2790 |
BUG_ON(nd->inode != dir->d_inode); |
b6183df7b vfs: do_last(): s... |
2791 2792 2793 2794 2795 2796 2797 2798 2799 |
} else { /* create side of things */ /* * This will *only* deal with leaving RCU mode - LOOKUP_JUMPED * has been cleared when we got to the last component we are * about to look up */ error = complete_walk(nd); if (error) |
2675a4eb6 fs/namei.c: get d... |
2800 |
return error; |
fe2d35ff0 switch non-create... |
2801 |
|
33e2208ac audit: vfs: fix a... |
2802 |
audit_inode(name, dir, LOOKUP_PARENT); |
b6183df7b vfs: do_last(): s... |
2803 2804 2805 |
error = -EISDIR; /* trailing slashes? */ if (nd->last.name[nd->last.len]) |
2675a4eb6 fs/namei.c: get d... |
2806 |
goto out; |
b6183df7b vfs: do_last(): s... |
2807 |
} |
a2c36b450 pull more into do... |
2808 |
|
16b1c1cd7 vfs: retry last c... |
2809 |
retry_lookup: |
64894cf84 simplify lookup_o... |
2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 |
if (op->open_flag & (O_CREAT | O_TRUNC | O_WRONLY | O_RDWR)) { error = mnt_want_write(nd->path.mnt); if (!error) got_write = true; /* * do _not_ fail yet - we might not need that or fail with * a different error; let lookup_open() decide; we'll be * dropping this one anyway. */ } |
a1e28038d pull the common p... |
2820 |
mutex_lock(&dir->d_inode->i_mutex); |
64894cf84 simplify lookup_o... |
2821 |
error = lookup_open(nd, path, file, op, got_write, opened); |
d58ffd35c vfs: add lookup_o... |
2822 |
mutex_unlock(&dir->d_inode->i_mutex); |
a1e28038d pull the common p... |
2823 |
|
2675a4eb6 fs/namei.c: get d... |
2824 2825 |
if (error <= 0) { if (error) |
d18e9008c vfs: add i_op->at... |
2826 |
goto out; |
47237687d ->atomic_open() p... |
2827 |
if ((*opened & FILE_CREATED) || |
496ad9aa8 new helper: file_... |
2828 |
!S_ISREG(file_inode(file)->i_mode)) |
77d660a8a vfs: do_last(): c... |
2829 |
will_truncate = false; |
d18e9008c vfs: add i_op->at... |
2830 |
|
adb5c2473 audit: make audit... |
2831 |
audit_inode(name, file->f_path.dentry, 0); |
d18e9008c vfs: add i_op->at... |
2832 2833 |
goto opened; } |
fb1cc555d gut do_filp_open(... |
2834 |
|
47237687d ->atomic_open() p... |
2835 |
if (*opened & FILE_CREATED) { |
9b44f1b39 move may_open() f... |
2836 |
/* Don't check for write permission, don't truncate */ |
ca344a894 do_last: unify ma... |
2837 |
open_flag &= ~O_TRUNC; |
77d660a8a vfs: do_last(): c... |
2838 |
will_truncate = false; |
bcda76524 Allow O_PATH for ... |
2839 |
acc_mode = MAY_OPEN; |
d58ffd35c vfs: add lookup_o... |
2840 |
path_to_nameidata(path, nd); |
e83db1672 vfs: do_last(): c... |
2841 |
goto finish_open_created; |
fb1cc555d gut do_filp_open(... |
2842 2843 2844 |
} /* |
3134f37e9 vfs: don't let do... |
2845 |
* create/update audit record if it already exists. |
fb1cc555d gut do_filp_open(... |
2846 |
*/ |
b18825a7c VFS: Put a small ... |
2847 |
if (d_is_positive(path->dentry)) |
adb5c2473 audit: make audit... |
2848 |
audit_inode(name, path->dentry, 0); |
fb1cc555d gut do_filp_open(... |
2849 |
|
d18e9008c vfs: add i_op->at... |
2850 2851 2852 2853 2854 |
/* * If atomic_open() acquired write access it is dropped now due to * possible mount and symlink following (this might be optimized away if * necessary...) */ |
64894cf84 simplify lookup_o... |
2855 |
if (got_write) { |
d18e9008c vfs: add i_op->at... |
2856 |
mnt_drop_write(nd->path.mnt); |
64894cf84 simplify lookup_o... |
2857 |
got_write = false; |
d18e9008c vfs: add i_op->at... |
2858 |
} |
fb1cc555d gut do_filp_open(... |
2859 |
error = -EEXIST; |
f8310c592 fix O_EXCL handli... |
2860 |
if ((open_flag & (O_EXCL | O_CREAT)) == (O_EXCL | O_CREAT)) |
fb1cc555d gut do_filp_open(... |
2861 |
goto exit_dput; |
9875cf806 Add a dentry op t... |
2862 2863 2864 |
error = follow_managed(path, nd->flags); if (error < 0) goto exit_dput; |
fb1cc555d gut do_filp_open(... |
2865 |
|
a3fbbde70 VFS: we need to s... |
2866 2867 |
if (error) nd->flags |= LOOKUP_JUMPED; |
decf34008 vfs: do_last(): u... |
2868 2869 |
BUG_ON(nd->flags & LOOKUP_RCU); inode = path->dentry->d_inode; |
5f5daac12 vfs: do_last() co... |
2870 2871 |
finish_lookup: /* we _can_ be in RCU mode here */ |
fb1cc555d gut do_filp_open(... |
2872 |
error = -ENOENT; |
22213318a fix races between... |
2873 |
if (!inode || d_is_negative(path->dentry)) { |
54c33e7f9 vfs: do_last(): m... |
2874 |
path_to_nameidata(path, nd); |
2675a4eb6 fs/namei.c: get d... |
2875 |
goto out; |
54c33e7f9 vfs: do_last(): m... |
2876 |
} |
9e67f3616 Kill is_link argu... |
2877 |
|
b18825a7c VFS: Put a small ... |
2878 |
if (should_follow_link(path->dentry, !symlink_ok)) { |
d45ea8679 vfs: make follow_... |
2879 2880 2881 |
if (nd->flags & LOOKUP_RCU) { if (unlikely(unlazy_walk(nd, path->dentry))) { error = -ECHILD; |
2675a4eb6 fs/namei.c: get d... |
2882 |
goto out; |
d45ea8679 vfs: make follow_... |
2883 2884 2885 |
} } BUG_ON(inode != path->dentry->d_inode); |
2675a4eb6 fs/namei.c: get d... |
2886 |
return 1; |
d45ea8679 vfs: make follow_... |
2887 |
} |
fb1cc555d gut do_filp_open(... |
2888 |
|
16b1c1cd7 vfs: retry last c... |
2889 2890 2891 2892 2893 2894 2895 2896 |
if ((nd->flags & LOOKUP_RCU) || nd->path.mnt != path->mnt) { path_to_nameidata(path, nd); } else { save_parent.dentry = nd->path.dentry; save_parent.mnt = mntget(path->mnt); nd->path.dentry = path->dentry; } |
decf34008 vfs: do_last(): u... |
2897 |
nd->inode = inode; |
a3fbbde70 VFS: we need to s... |
2898 |
/* Why this, you ask? _Now_ we might have grown LOOKUP_JUMPED... */ |
bc77daa78 do_last(): fix mi... |
2899 |
finish_open: |
a3fbbde70 VFS: we need to s... |
2900 |
error = complete_walk(nd); |
16b1c1cd7 vfs: retry last c... |
2901 2902 |
if (error) { path_put(&save_parent); |
2675a4eb6 fs/namei.c: get d... |
2903 |
return error; |
16b1c1cd7 vfs: retry last c... |
2904 |
} |
bc77daa78 do_last(): fix mi... |
2905 |
audit_inode(name, nd->path.dentry, 0); |
fb1cc555d gut do_filp_open(... |
2906 |
error = -EISDIR; |
44b1d5304 vfs: add d_is_dir() |
2907 |
if ((open_flag & O_CREAT) && d_is_dir(nd->path.dentry)) |
2675a4eb6 fs/namei.c: get d... |
2908 |
goto out; |
af2f55426 vfs: do_last(): c... |
2909 |
error = -ENOTDIR; |
44b1d5304 vfs: add d_is_dir() |
2910 |
if ((nd->flags & LOOKUP_DIRECTORY) && !d_can_lookup(nd->path.dentry)) |
2675a4eb6 fs/namei.c: get d... |
2911 |
goto out; |
6c0d46c49 fold __open_namei... |
2912 |
if (!S_ISREG(nd->inode->i_mode)) |
77d660a8a vfs: do_last(): c... |
2913 |
will_truncate = false; |
6c0d46c49 fold __open_namei... |
2914 |
|
0f9d1a10c expand finish_ope... |
2915 2916 2917 |
if (will_truncate) { error = mnt_want_write(nd->path.mnt); if (error) |
2675a4eb6 fs/namei.c: get d... |
2918 |
goto out; |
64894cf84 simplify lookup_o... |
2919 |
got_write = true; |
0f9d1a10c expand finish_ope... |
2920 |
} |
e83db1672 vfs: do_last(): c... |
2921 |
finish_open_created: |
bcda76524 Allow O_PATH for ... |
2922 |
error = may_open(&nd->path, acc_mode, open_flag); |
ca344a894 do_last: unify ma... |
2923 |
if (error) |
2675a4eb6 fs/namei.c: get d... |
2924 |
goto out; |
30d904947 kill struct opendata |
2925 2926 2927 |
file->f_path.mnt = nd->path.mnt; error = finish_open(file, nd->path.dentry, NULL, opened); if (error) { |
30d904947 kill struct opendata |
2928 |
if (error == -EOPENSTALE) |
f60dc3db6 vfs: do_last(): c... |
2929 |
goto stale_open; |
015c3bbcd vfs: remove open ... |
2930 |
goto out; |
f60dc3db6 vfs: do_last(): c... |
2931 |
} |
a8277b9ba vfs: move O_DIREC... |
2932 |
opened: |
2675a4eb6 fs/namei.c: get d... |
2933 |
error = open_check_o_direct(file); |
015c3bbcd vfs: remove open ... |
2934 2935 |
if (error) goto exit_fput; |
2675a4eb6 fs/namei.c: get d... |
2936 |
error = ima_file_check(file, op->acc_mode); |
aa4caadb7 vfs: do_last(): c... |
2937 2938 2939 2940 |
if (error) goto exit_fput; if (will_truncate) { |
2675a4eb6 fs/namei.c: get d... |
2941 |
error = handle_truncate(file); |
aa4caadb7 vfs: do_last(): c... |
2942 2943 |
if (error) goto exit_fput; |
0f9d1a10c expand finish_ope... |
2944 |
} |
ca344a894 do_last: unify ma... |
2945 |
out: |
64894cf84 simplify lookup_o... |
2946 |
if (got_write) |
0f9d1a10c expand finish_ope... |
2947 |
mnt_drop_write(nd->path.mnt); |
16b1c1cd7 vfs: retry last c... |
2948 |
path_put(&save_parent); |
e276ae672 vfs: do_last(): m... |
2949 |
terminate_walk(nd); |
2675a4eb6 fs/namei.c: get d... |
2950 |
return error; |
fb1cc555d gut do_filp_open(... |
2951 |
|
fb1cc555d gut do_filp_open(... |
2952 2953 |
exit_dput: path_put_conditional(path, nd); |
ca344a894 do_last: unify ma... |
2954 |
goto out; |
015c3bbcd vfs: remove open ... |
2955 |
exit_fput: |
2675a4eb6 fs/namei.c: get d... |
2956 2957 |
fput(file); goto out; |
015c3bbcd vfs: remove open ... |
2958 |
|
f60dc3db6 vfs: do_last(): c... |
2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 |
stale_open: /* If no saved parent or already retried then can't retry */ if (!save_parent.dentry || retried) goto out; BUG_ON(save_parent.dentry != dir); path_put(&nd->path); nd->path = save_parent; nd->inode = dir->d_inode; save_parent.mnt = NULL; save_parent.dentry = NULL; |
64894cf84 simplify lookup_o... |
2970 |
if (got_write) { |
f60dc3db6 vfs: do_last(): c... |
2971 |
mnt_drop_write(nd->path.mnt); |
64894cf84 simplify lookup_o... |
2972 |
got_write = false; |
f60dc3db6 vfs: do_last(): c... |
2973 2974 2975 |
} retried = true; goto retry_lookup; |
fb1cc555d gut do_filp_open(... |
2976 |
} |
60545d0d4 [O_TMPFILE] it's ... |
2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 |
static int do_tmpfile(int dfd, struct filename *pathname, struct nameidata *nd, int flags, const struct open_flags *op, struct file *file, int *opened) { static const struct qstr name = QSTR_INIT("/", 1); struct dentry *dentry, *child; struct inode *dir; int error = path_lookupat(dfd, pathname->name, flags | LOOKUP_DIRECTORY, nd); if (unlikely(error)) return error; error = mnt_want_write(nd->path.mnt); if (unlikely(error)) goto out; /* we want directory to be writable */ error = inode_permission(nd->inode, MAY_WRITE | MAY_EXEC); if (error) goto out2; dentry = nd->path.dentry; dir = dentry->d_inode; if (!dir->i_op->tmpfile) { error = -EOPNOTSUPP; goto out2; } child = d_alloc(dentry, &name); if (unlikely(!child)) { error = -ENOMEM; goto out2; } nd->flags &= ~LOOKUP_DIRECTORY; nd->flags |= op->intent; dput(nd->path.dentry); nd->path.dentry = child; error = dir->i_op->tmpfile(dir, nd->path.dentry, op->mode); if (error) goto out2; audit_inode(pathname, nd->path.dentry, 0); error = may_open(&nd->path, op->acc_mode, op->open_flag); if (error) goto out2; file->f_path.mnt = nd->path.mnt; error = finish_open(file, nd->path.dentry, NULL, opened); if (error) goto out2; error = open_check_o_direct(file); |
f4e0c30c1 allow the temp fi... |
3023 |
if (error) { |
60545d0d4 [O_TMPFILE] it's ... |
3024 |
fput(file); |
f4e0c30c1 allow the temp fi... |
3025 3026 3027 3028 3029 3030 |
} else if (!(op->open_flag & O_EXCL)) { struct inode *inode = file_inode(file); spin_lock(&inode->i_lock); inode->i_state |= I_LINKABLE; spin_unlock(&inode->i_lock); } |
60545d0d4 [O_TMPFILE] it's ... |
3031 3032 3033 3034 3035 3036 |
out2: mnt_drop_write(nd->path.mnt); out: path_put(&nd->path); return error; } |
669abf4e5 vfs: make path_op... |
3037 |
static struct file *path_openat(int dfd, struct filename *pathname, |
73d049a40 open-style analog... |
3038 |
struct nameidata *nd, const struct open_flags *op, int flags) |
1da177e4c Linux-2.6.12-rc2 |
3039 |
{ |
fe2d35ff0 switch non-create... |
3040 |
struct file *base = NULL; |
30d904947 kill struct opendata |
3041 |
struct file *file; |
9850c0565 Fix the -ESTALE h... |
3042 |
struct path path; |
47237687d ->atomic_open() p... |
3043 |
int opened = 0; |
13aab428a separate -ESTALE/... |
3044 |
int error; |
31e6b01f4 fs: rcu-walk for ... |
3045 |
|
30d904947 kill struct opendata |
3046 |
file = get_empty_filp(); |
1afc99bea propagate error f... |
3047 3048 |
if (IS_ERR(file)) return file; |
31e6b01f4 fs: rcu-walk for ... |
3049 |
|
30d904947 kill struct opendata |
3050 |
file->f_flags = op->open_flag; |
31e6b01f4 fs: rcu-walk for ... |
3051 |
|
bb458c644 Safer ABI for O_T... |
3052 |
if (unlikely(file->f_flags & __O_TMPFILE)) { |
60545d0d4 [O_TMPFILE] it's ... |
3053 3054 3055 |
error = do_tmpfile(dfd, pathname, nd, flags, op, file, &opened); goto out; } |
669abf4e5 vfs: make path_op... |
3056 |
error = path_init(dfd, pathname->name, flags | LOOKUP_PARENT, nd, &base); |
31e6b01f4 fs: rcu-walk for ... |
3057 |
if (unlikely(error)) |
2675a4eb6 fs/namei.c: get d... |
3058 |
goto out; |
31e6b01f4 fs: rcu-walk for ... |
3059 |
|
fe2d35ff0 switch non-create... |
3060 |
current->total_link_count = 0; |
669abf4e5 vfs: make path_op... |
3061 |
error = link_path_walk(pathname->name, nd); |
31e6b01f4 fs: rcu-walk for ... |
3062 |
if (unlikely(error)) |
2675a4eb6 fs/namei.c: get d... |
3063 |
goto out; |
1da177e4c Linux-2.6.12-rc2 |
3064 |
|
2675a4eb6 fs/namei.c: get d... |
3065 3066 |
error = do_last(nd, &path, file, op, &opened, pathname); while (unlikely(error > 0)) { /* trailing symlink */ |
7b9337aaf fs: namei fix ->p... |
3067 |
struct path link = path; |
def4af30c Get rid of symlin... |
3068 |
void *cookie; |
574197e0d tidy the trailing... |
3069 |
if (!(nd->flags & LOOKUP_FOLLOW)) { |
73d049a40 open-style analog... |
3070 3071 |
path_put_conditional(&path, nd); path_put(&nd->path); |
2675a4eb6 fs/namei.c: get d... |
3072 |
error = -ELOOP; |
40b39136f path_openat: clea... |
3073 3074 |
break; } |
800179c9b fs: add link rest... |
3075 3076 3077 |
error = may_follow_link(&link, nd); if (unlikely(error)) break; |
73d049a40 open-style analog... |
3078 3079 |
nd->flags |= LOOKUP_PARENT; nd->flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL); |
574197e0d tidy the trailing... |
3080 |
error = follow_link(&link, nd, &cookie); |
c3e380b0b Collect "operatio... |
3081 |
if (unlikely(error)) |
2675a4eb6 fs/namei.c: get d... |
3082 3083 |
break; error = do_last(nd, &path, file, op, &opened, pathname); |
574197e0d tidy the trailing... |
3084 |
put_link(nd, &link, cookie); |
806b681cb Turn do_link spag... |
3085 |
} |
10fa8e62f Unify exits in O_... |
3086 |
out: |
73d049a40 open-style analog... |
3087 3088 |
if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) path_put(&nd->root); |
fe2d35ff0 switch non-create... |
3089 3090 |
if (base) fput(base); |
2675a4eb6 fs/namei.c: get d... |
3091 3092 |
if (!(opened & FILE_OPENED)) { BUG_ON(!error); |
30d904947 kill struct opendata |
3093 |
put_filp(file); |
16b1c1cd7 vfs: retry last c... |
3094 |
} |
2675a4eb6 fs/namei.c: get d... |
3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 |
if (unlikely(error)) { if (error == -EOPENSTALE) { if (flags & LOOKUP_RCU) error = -ECHILD; else error = -ESTALE; } file = ERR_PTR(error); } return file; |
1da177e4c Linux-2.6.12-rc2 |
3105 |
} |
669abf4e5 vfs: make path_op... |
3106 |
struct file *do_filp_open(int dfd, struct filename *pathname, |
f9652e10c allow build_open_... |
3107 |
const struct open_flags *op) |
13aab428a separate -ESTALE/... |
3108 |
{ |
73d049a40 open-style analog... |
3109 |
struct nameidata nd; |
f9652e10c allow build_open_... |
3110 |
int flags = op->lookup_flags; |
13aab428a separate -ESTALE/... |
3111 |
struct file *filp; |
73d049a40 open-style analog... |
3112 |
filp = path_openat(dfd, pathname, &nd, op, flags | LOOKUP_RCU); |
13aab428a separate -ESTALE/... |
3113 |
if (unlikely(filp == ERR_PTR(-ECHILD))) |
73d049a40 open-style analog... |
3114 |
filp = path_openat(dfd, pathname, &nd, op, flags); |
13aab428a separate -ESTALE/... |
3115 |
if (unlikely(filp == ERR_PTR(-ESTALE))) |
73d049a40 open-style analog... |
3116 |
filp = path_openat(dfd, pathname, &nd, op, flags | LOOKUP_REVAL); |
13aab428a separate -ESTALE/... |
3117 3118 |
return filp; } |
73d049a40 open-style analog... |
3119 |
struct file *do_file_open_root(struct dentry *dentry, struct vfsmount *mnt, |
f9652e10c allow build_open_... |
3120 |
const char *name, const struct open_flags *op) |
73d049a40 open-style analog... |
3121 3122 3123 |
{ struct nameidata nd; struct file *file; |
669abf4e5 vfs: make path_op... |
3124 |
struct filename filename = { .name = name }; |
f9652e10c allow build_open_... |
3125 |
int flags = op->lookup_flags | LOOKUP_ROOT; |
73d049a40 open-style analog... |
3126 3127 3128 |
nd.root.mnt = mnt; nd.root.dentry = dentry; |
b18825a7c VFS: Put a small ... |
3129 |
if (d_is_symlink(dentry) && op->intent & LOOKUP_OPEN) |
73d049a40 open-style analog... |
3130 |
return ERR_PTR(-ELOOP); |
669abf4e5 vfs: make path_op... |
3131 |
file = path_openat(-1, &filename, &nd, op, flags | LOOKUP_RCU); |
73d049a40 open-style analog... |
3132 |
if (unlikely(file == ERR_PTR(-ECHILD))) |
669abf4e5 vfs: make path_op... |
3133 |
file = path_openat(-1, &filename, &nd, op, flags); |
73d049a40 open-style analog... |
3134 |
if (unlikely(file == ERR_PTR(-ESTALE))) |
669abf4e5 vfs: make path_op... |
3135 |
file = path_openat(-1, &filename, &nd, op, flags | LOOKUP_REVAL); |
73d049a40 open-style analog... |
3136 3137 |
return file; } |
1ac12b4b6 vfs: turn is_dir ... |
3138 3139 |
struct dentry *kern_path_create(int dfd, const char *pathname, struct path *path, unsigned int lookup_flags) |
1da177e4c Linux-2.6.12-rc2 |
3140 |
{ |
c663e5d80 [PATCH] add some ... |
3141 |
struct dentry *dentry = ERR_PTR(-EEXIST); |
ed75e95de kill lookup_create() |
3142 |
struct nameidata nd; |
c30dabfe5 fs: Push mnt_want... |
3143 |
int err2; |
1ac12b4b6 vfs: turn is_dir ... |
3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 |
int error; bool is_dir = (lookup_flags & LOOKUP_DIRECTORY); /* * Note that only LOOKUP_REVAL and LOOKUP_DIRECTORY matter here. Any * other flags passed in are ignored! */ lookup_flags &= LOOKUP_REVAL; error = do_path_lookup(dfd, pathname, LOOKUP_PARENT|lookup_flags, &nd); |
ed75e95de kill lookup_create() |
3154 3155 |
if (error) return ERR_PTR(error); |
1da177e4c Linux-2.6.12-rc2 |
3156 |
|
c663e5d80 [PATCH] add some ... |
3157 3158 3159 3160 |
/* * Yucky last component or no last component at all? * (foo/., foo/.., /////) */ |
ed75e95de kill lookup_create() |
3161 3162 3163 3164 |
if (nd.last_type != LAST_NORM) goto out; nd.flags &= ~LOOKUP_PARENT; nd.flags |= LOOKUP_CREATE | LOOKUP_EXCL; |
c663e5d80 [PATCH] add some ... |
3165 |
|
c30dabfe5 fs: Push mnt_want... |
3166 3167 |
/* don't fail immediately if it's r/o, at least try to report other errors */ err2 = mnt_want_write(nd.path.mnt); |
c663e5d80 [PATCH] add some ... |
3168 3169 3170 |
/* * Do the final lookup. */ |
ed75e95de kill lookup_create() |
3171 3172 |
mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); dentry = lookup_hash(&nd); |
1da177e4c Linux-2.6.12-rc2 |
3173 |
if (IS_ERR(dentry)) |
a8104a9fc pull mnt_want_wri... |
3174 |
goto unlock; |
c663e5d80 [PATCH] add some ... |
3175 |
|
a8104a9fc pull mnt_want_wri... |
3176 |
error = -EEXIST; |
b18825a7c VFS: Put a small ... |
3177 |
if (d_is_positive(dentry)) |
a8104a9fc pull mnt_want_wri... |
3178 |
goto fail; |
b18825a7c VFS: Put a small ... |
3179 |
|
c663e5d80 [PATCH] add some ... |
3180 3181 3182 3183 3184 3185 |
/* * Special case - lookup gave negative, but... we had foo/bar/ * From the vfs_mknod() POV we just have a negative dentry - * all is fine. Let's be bastards - you had / on the end, you've * been asking for (non-existent) directory. -ENOENT for you. */ |
ed75e95de kill lookup_create() |
3186 |
if (unlikely(!is_dir && nd.last.name[nd.last.len])) { |
a8104a9fc pull mnt_want_wri... |
3187 |
error = -ENOENT; |
ed75e95de kill lookup_create() |
3188 |
goto fail; |
e9baf6e59 [PATCH] return to... |
3189 |
} |
c30dabfe5 fs: Push mnt_want... |
3190 3191 |
if (unlikely(err2)) { error = err2; |
a8104a9fc pull mnt_want_wri... |
3192 |
goto fail; |
c30dabfe5 fs: Push mnt_want... |
3193 |
} |
ed75e95de kill lookup_create() |
3194 |
*path = nd.path; |
1da177e4c Linux-2.6.12-rc2 |
3195 |
return dentry; |
1da177e4c Linux-2.6.12-rc2 |
3196 |
fail: |
a8104a9fc pull mnt_want_wri... |
3197 3198 3199 |
dput(dentry); dentry = ERR_PTR(error); unlock: |
ed75e95de kill lookup_create() |
3200 |
mutex_unlock(&nd.path.dentry->d_inode->i_mutex); |
c30dabfe5 fs: Push mnt_want... |
3201 3202 |
if (!err2) mnt_drop_write(nd.path.mnt); |
ed75e95de kill lookup_create() |
3203 3204 |
out: path_put(&nd.path); |
1da177e4c Linux-2.6.12-rc2 |
3205 3206 |
return dentry; } |
dae6ad8f3 new helpers: kern... |
3207 |
EXPORT_SYMBOL(kern_path_create); |
921a1650d new helper: done_... |
3208 3209 3210 3211 |
void done_path_create(struct path *path, struct dentry *dentry) { dput(dentry); mutex_unlock(&path->dentry->d_inode->i_mutex); |
a8104a9fc pull mnt_want_wri... |
3212 |
mnt_drop_write(path->mnt); |
921a1650d new helper: done_... |
3213 3214 3215 |
path_put(path); } EXPORT_SYMBOL(done_path_create); |
1ac12b4b6 vfs: turn is_dir ... |
3216 3217 |
struct dentry *user_path_create(int dfd, const char __user *pathname, struct path *path, unsigned int lookup_flags) |
dae6ad8f3 new helpers: kern... |
3218 |
{ |
91a27b2a7 vfs: define struc... |
3219 |
struct filename *tmp = getname(pathname); |
dae6ad8f3 new helpers: kern... |
3220 3221 3222 |
struct dentry *res; if (IS_ERR(tmp)) return ERR_CAST(tmp); |
1ac12b4b6 vfs: turn is_dir ... |
3223 |
res = kern_path_create(dfd, tmp->name, path, lookup_flags); |
dae6ad8f3 new helpers: kern... |
3224 3225 3226 3227 |
putname(tmp); return res; } EXPORT_SYMBOL(user_path_create); |
1a67aafb5 switch ->mknod() ... |
3228 |
int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4c Linux-2.6.12-rc2 |
3229 |
{ |
a95164d97 [patch 3/4] vfs: ... |
3230 |
int error = may_create(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
3231 3232 3233 |
if (error) return error; |
975d6b393 vfs: Don't allow ... |
3234 |
if ((S_ISCHR(mode) || S_ISBLK(mode)) && !capable(CAP_MKNOD)) |
1da177e4c Linux-2.6.12-rc2 |
3235 |
return -EPERM; |
acfa4380e inode->i_op is ne... |
3236 |
if (!dir->i_op->mknod) |
1da177e4c Linux-2.6.12-rc2 |
3237 |
return -EPERM; |
08ce5f16e cgroups: implemen... |
3238 3239 3240 |
error = devcgroup_inode_mknod(mode, dev); if (error) return error; |
1da177e4c Linux-2.6.12-rc2 |
3241 3242 3243 |
error = security_inode_mknod(dir, dentry, mode, dev); if (error) return error; |
1da177e4c Linux-2.6.12-rc2 |
3244 |
error = dir->i_op->mknod(dir, dentry, mode, dev); |
a74574aaf [PATCH] Remove se... |
3245 |
if (!error) |
f38aa9422 [PATCH] Pass dent... |
3246 |
fsnotify_create(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
3247 3248 |
return error; } |
4d3595073 namei.c: move EXP... |
3249 |
EXPORT_SYMBOL(vfs_mknod); |
1da177e4c Linux-2.6.12-rc2 |
3250 |
|
f69aac000 switch may_mknod(... |
3251 |
static int may_mknod(umode_t mode) |
463c31972 [PATCH] r/o bind ... |
3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262 3263 3264 3265 3266 |
{ switch (mode & S_IFMT) { case S_IFREG: case S_IFCHR: case S_IFBLK: case S_IFIFO: case S_IFSOCK: case 0: /* zero mode translates to S_IFREG */ return 0; case S_IFDIR: return -EPERM; default: return -EINVAL; } } |
8208a22bb switch sys_mknoda... |
3267 |
SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode, |
2e4d0924e [CVE-2009-0029] S... |
3268 |
unsigned, dev) |
1da177e4c Linux-2.6.12-rc2 |
3269 |
{ |
2ad94ae65 [PATCH] new (loca... |
3270 |
struct dentry *dentry; |
dae6ad8f3 new helpers: kern... |
3271 3272 |
struct path path; int error; |
972567f14 vfs: fix mknodat ... |
3273 |
unsigned int lookup_flags = 0; |
1da177e4c Linux-2.6.12-rc2 |
3274 |
|
8e4bfca1d mknod: take sanit... |
3275 3276 3277 |
error = may_mknod(mode); if (error) return error; |
972567f14 vfs: fix mknodat ... |
3278 3279 |
retry: dentry = user_path_create(dfd, filename, &path, lookup_flags); |
dae6ad8f3 new helpers: kern... |
3280 3281 |
if (IS_ERR(dentry)) return PTR_ERR(dentry); |
2ad94ae65 [PATCH] new (loca... |
3282 |
|
dae6ad8f3 new helpers: kern... |
3283 |
if (!IS_POSIXACL(path.dentry->d_inode)) |
ce3b0f8d5 New helper - curr... |
3284 |
mode &= ~current_umask(); |
dae6ad8f3 new helpers: kern... |
3285 |
error = security_path_mknod(&path, dentry, mode, dev); |
be6d3e56a introduce new LSM... |
3286 |
if (error) |
a8104a9fc pull mnt_want_wri... |
3287 |
goto out; |
463c31972 [PATCH] r/o bind ... |
3288 |
switch (mode & S_IFMT) { |
1da177e4c Linux-2.6.12-rc2 |
3289 |
case 0: case S_IFREG: |
312b63fba don't pass nameid... |
3290 |
error = vfs_create(path.dentry->d_inode,dentry,mode,true); |
1da177e4c Linux-2.6.12-rc2 |
3291 3292 |
break; case S_IFCHR: case S_IFBLK: |
dae6ad8f3 new helpers: kern... |
3293 |
error = vfs_mknod(path.dentry->d_inode,dentry,mode, |
1da177e4c Linux-2.6.12-rc2 |
3294 3295 3296 |
new_decode_dev(dev)); break; case S_IFIFO: case S_IFSOCK: |
dae6ad8f3 new helpers: kern... |
3297 |
error = vfs_mknod(path.dentry->d_inode,dentry,mode,0); |
1da177e4c Linux-2.6.12-rc2 |
3298 |
break; |
1da177e4c Linux-2.6.12-rc2 |
3299 |
} |
a8104a9fc pull mnt_want_wri... |
3300 |
out: |
921a1650d new helper: done_... |
3301 |
done_path_create(&path, dentry); |
972567f14 vfs: fix mknodat ... |
3302 3303 3304 3305 |
if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } |
1da177e4c Linux-2.6.12-rc2 |
3306 3307 |
return error; } |
8208a22bb switch sys_mknoda... |
3308 |
SYSCALL_DEFINE3(mknod, const char __user *, filename, umode_t, mode, unsigned, dev) |
5590ff0d5 [PATCH] vfs: *at ... |
3309 3310 3311 |
{ return sys_mknodat(AT_FDCWD, filename, mode, dev); } |
18bb1db3e switch vfs_mkdir(... |
3312 |
int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4c Linux-2.6.12-rc2 |
3313 |
{ |
a95164d97 [patch 3/4] vfs: ... |
3314 |
int error = may_create(dir, dentry); |
8de527787 vfs: check i_nlin... |
3315 |
unsigned max_links = dir->i_sb->s_max_links; |
1da177e4c Linux-2.6.12-rc2 |
3316 3317 3318 |
if (error) return error; |
acfa4380e inode->i_op is ne... |
3319 |
if (!dir->i_op->mkdir) |
1da177e4c Linux-2.6.12-rc2 |
3320 3321 3322 3323 3324 3325 |
return -EPERM; mode &= (S_IRWXUGO|S_ISVTX); error = security_inode_mkdir(dir, dentry, mode); if (error) return error; |
8de527787 vfs: check i_nlin... |
3326 3327 |
if (max_links && dir->i_nlink >= max_links) return -EMLINK; |
1da177e4c Linux-2.6.12-rc2 |
3328 |
error = dir->i_op->mkdir(dir, dentry, mode); |
a74574aaf [PATCH] Remove se... |
3329 |
if (!error) |
f38aa9422 [PATCH] Pass dent... |
3330 |
fsnotify_mkdir(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
3331 3332 |
return error; } |
4d3595073 namei.c: move EXP... |
3333 |
EXPORT_SYMBOL(vfs_mkdir); |
1da177e4c Linux-2.6.12-rc2 |
3334 |
|
a218d0fdc switch open and m... |
3335 |
SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode) |
1da177e4c Linux-2.6.12-rc2 |
3336 |
{ |
6902d925d [PATCH] r/o bind ... |
3337 |
struct dentry *dentry; |
dae6ad8f3 new helpers: kern... |
3338 3339 |
struct path path; int error; |
b76d8b822 vfs: fix mkdirat ... |
3340 |
unsigned int lookup_flags = LOOKUP_DIRECTORY; |
1da177e4c Linux-2.6.12-rc2 |
3341 |
|
b76d8b822 vfs: fix mkdirat ... |
3342 3343 |
retry: dentry = user_path_create(dfd, pathname, &path, lookup_flags); |
6902d925d [PATCH] r/o bind ... |
3344 |
if (IS_ERR(dentry)) |
dae6ad8f3 new helpers: kern... |
3345 |
return PTR_ERR(dentry); |
1da177e4c Linux-2.6.12-rc2 |
3346 |
|
dae6ad8f3 new helpers: kern... |
3347 |
if (!IS_POSIXACL(path.dentry->d_inode)) |
ce3b0f8d5 New helper - curr... |
3348 |
mode &= ~current_umask(); |
dae6ad8f3 new helpers: kern... |
3349 |
error = security_path_mkdir(&path, dentry, mode); |
a8104a9fc pull mnt_want_wri... |
3350 3351 |
if (!error) error = vfs_mkdir(path.dentry->d_inode, dentry, mode); |
921a1650d new helper: done_... |
3352 |
done_path_create(&path, dentry); |
b76d8b822 vfs: fix mkdirat ... |
3353 3354 3355 3356 |
if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } |
1da177e4c Linux-2.6.12-rc2 |
3357 3358 |
return error; } |
a218d0fdc switch open and m... |
3359 |
SYSCALL_DEFINE2(mkdir, const char __user *, pathname, umode_t, mode) |
5590ff0d5 [PATCH] vfs: *at ... |
3360 3361 3362 |
{ return sys_mkdirat(AT_FDCWD, pathname, mode); } |
1da177e4c Linux-2.6.12-rc2 |
3363 |
/* |
a71905f0d vfs: update dentr... |
3364 |
* The dentry_unhash() helper will try to drop the dentry early: we |
c0d025948 vfs: fix out-of-d... |
3365 |
* should have a usage count of 1 if we're the only user of this |
a71905f0d vfs: update dentr... |
3366 3367 |
* dentry, and if that is true (possibly after pruning the dcache), * then we drop the dentry now. |
1da177e4c Linux-2.6.12-rc2 |
3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 |
* * A low-level filesystem can, if it choses, legally * do a * * if (!d_unhashed(dentry)) * return -EBUSY; * * if it cannot handle the case of removing a directory * that is still in use by something else.. */ void dentry_unhash(struct dentry *dentry) { |
dc168427e [PATCH] VFS: extr... |
3380 |
shrink_dcache_parent(dentry); |
1da177e4c Linux-2.6.12-rc2 |
3381 |
spin_lock(&dentry->d_lock); |
98474236f vfs: make the den... |
3382 |
if (dentry->d_lockref.count == 1) |
1da177e4c Linux-2.6.12-rc2 |
3383 3384 |
__d_drop(dentry); spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
3385 |
} |
4d3595073 namei.c: move EXP... |
3386 |
EXPORT_SYMBOL(dentry_unhash); |
1da177e4c Linux-2.6.12-rc2 |
3387 3388 3389 3390 3391 3392 3393 |
int vfs_rmdir(struct inode *dir, struct dentry *dentry) { int error = may_delete(dir, dentry, 1); if (error) return error; |
acfa4380e inode->i_op is ne... |
3394 |
if (!dir->i_op->rmdir) |
1da177e4c Linux-2.6.12-rc2 |
3395 |
return -EPERM; |
1d2ef5901 restore pinning t... |
3396 |
dget(dentry); |
1b1dcc1b5 [PATCH] mutex sub... |
3397 |
mutex_lock(&dentry->d_inode->i_mutex); |
912dbc15d vfs: clean up vfs... |
3398 3399 |
error = -EBUSY; |
1da177e4c Linux-2.6.12-rc2 |
3400 |
if (d_mountpoint(dentry)) |
912dbc15d vfs: clean up vfs... |
3401 3402 3403 3404 3405 |
goto out; error = security_inode_rmdir(dir, dentry); if (error) goto out; |
3cebde241 vfs: shrink_dcach... |
3406 |
shrink_dcache_parent(dentry); |
912dbc15d vfs: clean up vfs... |
3407 3408 3409 3410 3411 3412 3413 3414 |
error = dir->i_op->rmdir(dir, dentry); if (error) goto out; dentry->d_inode->i_flags |= S_DEAD; dont_mount(dentry); out: |
1b1dcc1b5 [PATCH] mutex sub... |
3415 |
mutex_unlock(&dentry->d_inode->i_mutex); |
1d2ef5901 restore pinning t... |
3416 |
dput(dentry); |
912dbc15d vfs: clean up vfs... |
3417 |
if (!error) |
1da177e4c Linux-2.6.12-rc2 |
3418 |
d_delete(dentry); |
1da177e4c Linux-2.6.12-rc2 |
3419 3420 |
return error; } |
4d3595073 namei.c: move EXP... |
3421 |
EXPORT_SYMBOL(vfs_rmdir); |
1da177e4c Linux-2.6.12-rc2 |
3422 |
|
5590ff0d5 [PATCH] vfs: *at ... |
3423 |
static long do_rmdir(int dfd, const char __user *pathname) |
1da177e4c Linux-2.6.12-rc2 |
3424 3425 |
{ int error = 0; |
91a27b2a7 vfs: define struc... |
3426 |
struct filename *name; |
1da177e4c Linux-2.6.12-rc2 |
3427 3428 |
struct dentry *dentry; struct nameidata nd; |
c6ee92069 vfs: make do_rmdi... |
3429 3430 3431 |
unsigned int lookup_flags = 0; retry: name = user_path_parent(dfd, pathname, &nd, lookup_flags); |
91a27b2a7 vfs: define struc... |
3432 3433 |
if (IS_ERR(name)) return PTR_ERR(name); |
1da177e4c Linux-2.6.12-rc2 |
3434 3435 |
switch(nd.last_type) { |
0612d9fb2 [PATCH vfs-2.6 5/... |
3436 3437 3438 3439 3440 3441 3442 3443 3444 |
case LAST_DOTDOT: error = -ENOTEMPTY; goto exit1; case LAST_DOT: error = -EINVAL; goto exit1; case LAST_ROOT: error = -EBUSY; goto exit1; |
1da177e4c Linux-2.6.12-rc2 |
3445 |
} |
0612d9fb2 [PATCH vfs-2.6 5/... |
3446 3447 |
nd.flags &= ~LOOKUP_PARENT; |
c30dabfe5 fs: Push mnt_want... |
3448 3449 3450 |
error = mnt_want_write(nd.path.mnt); if (error) goto exit1; |
0612d9fb2 [PATCH vfs-2.6 5/... |
3451 |
|
4ac913785 Embed a struct pa... |
3452 |
mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); |
49705b774 [PATCH] sanitize ... |
3453 |
dentry = lookup_hash(&nd); |
1da177e4c Linux-2.6.12-rc2 |
3454 |
error = PTR_ERR(dentry); |
6902d925d [PATCH] r/o bind ... |
3455 3456 |
if (IS_ERR(dentry)) goto exit2; |
e6bc45d65 vfs: make unlink(... |
3457 3458 3459 3460 |
if (!dentry->d_inode) { error = -ENOENT; goto exit3; } |
be6d3e56a introduce new LSM... |
3461 3462 |
error = security_path_rmdir(&nd.path, dentry); if (error) |
c30dabfe5 fs: Push mnt_want... |
3463 |
goto exit3; |
4ac913785 Embed a struct pa... |
3464 |
error = vfs_rmdir(nd.path.dentry->d_inode, dentry); |
0622753b8 [PATCH] r/o bind ... |
3465 |
exit3: |
6902d925d [PATCH] r/o bind ... |
3466 3467 |
dput(dentry); exit2: |
4ac913785 Embed a struct pa... |
3468 |
mutex_unlock(&nd.path.dentry->d_inode->i_mutex); |
c30dabfe5 fs: Push mnt_want... |
3469 |
mnt_drop_write(nd.path.mnt); |
1da177e4c Linux-2.6.12-rc2 |
3470 |
exit1: |
1d957f9bf Introduce path_put() |
3471 |
path_put(&nd.path); |
1da177e4c Linux-2.6.12-rc2 |
3472 |
putname(name); |
c6ee92069 vfs: make do_rmdi... |
3473 3474 3475 3476 |
if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } |
1da177e4c Linux-2.6.12-rc2 |
3477 3478 |
return error; } |
3cdad4288 [CVE-2009-0029] S... |
3479 |
SYSCALL_DEFINE1(rmdir, const char __user *, pathname) |
5590ff0d5 [PATCH] vfs: *at ... |
3480 3481 3482 |
{ return do_rmdir(AT_FDCWD, pathname); } |
b21996e36 locks: break dele... |
3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 |
/** * vfs_unlink - unlink a filesystem object * @dir: parent directory * @dentry: victim * @delegated_inode: returns victim inode, if the inode is delegated. * * The caller must hold dir->i_mutex. * * If vfs_unlink discovers a delegation, it will return -EWOULDBLOCK and * return a reference to the inode in delegated_inode. The caller * should then break the delegation on that inode and retry. Because * breaking a delegation may take a long time, the caller should drop * dir->i_mutex before doing so. * * Alternatively, a caller may pass NULL for delegated_inode. This may * be appropriate for callers that expect the underlying filesystem not * to be NFS exported. */ int vfs_unlink(struct inode *dir, struct dentry *dentry, struct inode **delegated_inode) |
1da177e4c Linux-2.6.12-rc2 |
3502 |
{ |
9accbb977 namei: minor vfs_... |
3503 |
struct inode *target = dentry->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
3504 3505 3506 3507 |
int error = may_delete(dir, dentry, 0); if (error) return error; |
acfa4380e inode->i_op is ne... |
3508 |
if (!dir->i_op->unlink) |
1da177e4c Linux-2.6.12-rc2 |
3509 |
return -EPERM; |
9accbb977 namei: minor vfs_... |
3510 |
mutex_lock(&target->i_mutex); |
1da177e4c Linux-2.6.12-rc2 |
3511 3512 3513 3514 |
if (d_mountpoint(dentry)) error = -EBUSY; else { error = security_inode_unlink(dir, dentry); |
bec1052e5 set S_DEAD on unl... |
3515 |
if (!error) { |
5a14696c1 locks: helper fun... |
3516 3517 |
error = try_break_deleg(target, delegated_inode); if (error) |
b21996e36 locks: break dele... |
3518 |
goto out; |
1da177e4c Linux-2.6.12-rc2 |
3519 |
error = dir->i_op->unlink(dir, dentry); |
bec1052e5 set S_DEAD on unl... |
3520 |
if (!error) |
d83c49f3e Fix the regressio... |
3521 |
dont_mount(dentry); |
bec1052e5 set S_DEAD on unl... |
3522 |
} |
1da177e4c Linux-2.6.12-rc2 |
3523 |
} |
b21996e36 locks: break dele... |
3524 |
out: |
9accbb977 namei: minor vfs_... |
3525 |
mutex_unlock(&target->i_mutex); |
1da177e4c Linux-2.6.12-rc2 |
3526 3527 3528 |
/* We don't d_delete() NFS sillyrenamed files--they still exist. */ if (!error && !(dentry->d_flags & DCACHE_NFSFS_RENAMED)) { |
9accbb977 namei: minor vfs_... |
3529 |
fsnotify_link_count(target); |
e234f35c5 [PATCH] inotify d... |
3530 |
d_delete(dentry); |
1da177e4c Linux-2.6.12-rc2 |
3531 |
} |
0eeca2830 [PATCH] inotify |
3532 |
|
1da177e4c Linux-2.6.12-rc2 |
3533 3534 |
return error; } |
4d3595073 namei.c: move EXP... |
3535 |
EXPORT_SYMBOL(vfs_unlink); |
1da177e4c Linux-2.6.12-rc2 |
3536 3537 3538 |
/* * Make sure that the actual truncation of the file will occur outside its |
1b1dcc1b5 [PATCH] mutex sub... |
3539 |
* directory's i_mutex. Truncate can take a long time if there is a lot of |
1da177e4c Linux-2.6.12-rc2 |
3540 3541 3542 |
* writeout happening, and we don't want to prevent access to the directory * while waiting on the I/O. */ |
5590ff0d5 [PATCH] vfs: *at ... |
3543 |
static long do_unlinkat(int dfd, const char __user *pathname) |
1da177e4c Linux-2.6.12-rc2 |
3544 |
{ |
2ad94ae65 [PATCH] new (loca... |
3545 |
int error; |
91a27b2a7 vfs: define struc... |
3546 |
struct filename *name; |
1da177e4c Linux-2.6.12-rc2 |
3547 3548 3549 |
struct dentry *dentry; struct nameidata nd; struct inode *inode = NULL; |
b21996e36 locks: break dele... |
3550 |
struct inode *delegated_inode = NULL; |
5d18f8133 vfs: make do_unli... |
3551 3552 3553 |
unsigned int lookup_flags = 0; retry: name = user_path_parent(dfd, pathname, &nd, lookup_flags); |
91a27b2a7 vfs: define struc... |
3554 3555 |
if (IS_ERR(name)) return PTR_ERR(name); |
2ad94ae65 [PATCH] new (loca... |
3556 |
|
1da177e4c Linux-2.6.12-rc2 |
3557 3558 3559 |
error = -EISDIR; if (nd.last_type != LAST_NORM) goto exit1; |
0612d9fb2 [PATCH vfs-2.6 5/... |
3560 3561 |
nd.flags &= ~LOOKUP_PARENT; |
c30dabfe5 fs: Push mnt_want... |
3562 3563 3564 |
error = mnt_want_write(nd.path.mnt); if (error) goto exit1; |
b21996e36 locks: break dele... |
3565 |
retry_deleg: |
4ac913785 Embed a struct pa... |
3566 |
mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); |
49705b774 [PATCH] sanitize ... |
3567 |
dentry = lookup_hash(&nd); |
1da177e4c Linux-2.6.12-rc2 |
3568 3569 3570 |
error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { /* Why not before? Because we want correct error value */ |
50338b889 fix wrong iput on... |
3571 3572 |
if (nd.last.name[nd.last.len]) goto slashes; |
1da177e4c Linux-2.6.12-rc2 |
3573 |
inode = dentry->d_inode; |
b18825a7c VFS: Put a small ... |
3574 |
if (d_is_negative(dentry)) |
e6bc45d65 vfs: make unlink(... |
3575 3576 |
goto slashes; ihold(inode); |
be6d3e56a introduce new LSM... |
3577 3578 |
error = security_path_unlink(&nd.path, dentry); if (error) |
c30dabfe5 fs: Push mnt_want... |
3579 |
goto exit2; |
b21996e36 locks: break dele... |
3580 |
error = vfs_unlink(nd.path.dentry->d_inode, dentry, &delegated_inode); |
c30dabfe5 fs: Push mnt_want... |
3581 |
exit2: |
1da177e4c Linux-2.6.12-rc2 |
3582 3583 |
dput(dentry); } |
4ac913785 Embed a struct pa... |
3584 |
mutex_unlock(&nd.path.dentry->d_inode->i_mutex); |
1da177e4c Linux-2.6.12-rc2 |
3585 3586 |
if (inode) iput(inode); /* truncate the inode here */ |
b21996e36 locks: break dele... |
3587 3588 |
inode = NULL; if (delegated_inode) { |
5a14696c1 locks: helper fun... |
3589 |
error = break_deleg_wait(&delegated_inode); |
b21996e36 locks: break dele... |
3590 3591 3592 |
if (!error) goto retry_deleg; } |
c30dabfe5 fs: Push mnt_want... |
3593 |
mnt_drop_write(nd.path.mnt); |
1da177e4c Linux-2.6.12-rc2 |
3594 |
exit1: |
1d957f9bf Introduce path_put() |
3595 |
path_put(&nd.path); |
1da177e4c Linux-2.6.12-rc2 |
3596 |
putname(name); |
5d18f8133 vfs: make do_unli... |
3597 3598 3599 3600 3601 |
if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; inode = NULL; goto retry; } |
1da177e4c Linux-2.6.12-rc2 |
3602 3603 3604 |
return error; slashes: |
b18825a7c VFS: Put a small ... |
3605 3606 |
if (d_is_negative(dentry)) error = -ENOENT; |
44b1d5304 vfs: add d_is_dir() |
3607 |
else if (d_is_dir(dentry)) |
b18825a7c VFS: Put a small ... |
3608 3609 3610 |
error = -EISDIR; else error = -ENOTDIR; |
1da177e4c Linux-2.6.12-rc2 |
3611 3612 |
goto exit2; } |
2e4d0924e [CVE-2009-0029] S... |
3613 |
SYSCALL_DEFINE3(unlinkat, int, dfd, const char __user *, pathname, int, flag) |
5590ff0d5 [PATCH] vfs: *at ... |
3614 3615 3616 3617 3618 3619 3620 3621 3622 |
{ if ((flag & ~AT_REMOVEDIR) != 0) return -EINVAL; if (flag & AT_REMOVEDIR) return do_rmdir(dfd, pathname); return do_unlinkat(dfd, pathname); } |
3480b2574 [CVE-2009-0029] S... |
3623 |
SYSCALL_DEFINE1(unlink, const char __user *, pathname) |
5590ff0d5 [PATCH] vfs: *at ... |
3624 3625 3626 |
{ return do_unlinkat(AT_FDCWD, pathname); } |
db2e747b1 [patch 5/5] vfs: ... |
3627 |
int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname) |
1da177e4c Linux-2.6.12-rc2 |
3628 |
{ |
a95164d97 [patch 3/4] vfs: ... |
3629 |
int error = may_create(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
3630 3631 3632 |
if (error) return error; |
acfa4380e inode->i_op is ne... |
3633 |
if (!dir->i_op->symlink) |
1da177e4c Linux-2.6.12-rc2 |
3634 3635 3636 3637 3638 |
return -EPERM; error = security_inode_symlink(dir, dentry, oldname); if (error) return error; |
1da177e4c Linux-2.6.12-rc2 |
3639 |
error = dir->i_op->symlink(dir, dentry, oldname); |
a74574aaf [PATCH] Remove se... |
3640 |
if (!error) |
f38aa9422 [PATCH] Pass dent... |
3641 |
fsnotify_create(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
3642 3643 |
return error; } |
4d3595073 namei.c: move EXP... |
3644 |
EXPORT_SYMBOL(vfs_symlink); |
1da177e4c Linux-2.6.12-rc2 |
3645 |
|
2e4d0924e [CVE-2009-0029] S... |
3646 3647 |
SYSCALL_DEFINE3(symlinkat, const char __user *, oldname, int, newdfd, const char __user *, newname) |
1da177e4c Linux-2.6.12-rc2 |
3648 |
{ |
2ad94ae65 [PATCH] new (loca... |
3649 |
int error; |
91a27b2a7 vfs: define struc... |
3650 |
struct filename *from; |
6902d925d [PATCH] r/o bind ... |
3651 |
struct dentry *dentry; |
dae6ad8f3 new helpers: kern... |
3652 |
struct path path; |
f46d3567b vfs: fix symlinka... |
3653 |
unsigned int lookup_flags = 0; |
1da177e4c Linux-2.6.12-rc2 |
3654 3655 |
from = getname(oldname); |
2ad94ae65 [PATCH] new (loca... |
3656 |
if (IS_ERR(from)) |
1da177e4c Linux-2.6.12-rc2 |
3657 |
return PTR_ERR(from); |
f46d3567b vfs: fix symlinka... |
3658 3659 |
retry: dentry = user_path_create(newdfd, newname, &path, lookup_flags); |
6902d925d [PATCH] r/o bind ... |
3660 3661 |
error = PTR_ERR(dentry); if (IS_ERR(dentry)) |
dae6ad8f3 new helpers: kern... |
3662 |
goto out_putname; |
6902d925d [PATCH] r/o bind ... |
3663 |
|
91a27b2a7 vfs: define struc... |
3664 |
error = security_path_symlink(&path, dentry, from->name); |
a8104a9fc pull mnt_want_wri... |
3665 |
if (!error) |
91a27b2a7 vfs: define struc... |
3666 |
error = vfs_symlink(path.dentry->d_inode, dentry, from->name); |
921a1650d new helper: done_... |
3667 |
done_path_create(&path, dentry); |
f46d3567b vfs: fix symlinka... |
3668 3669 3670 3671 |
if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } |
6902d925d [PATCH] r/o bind ... |
3672 |
out_putname: |
1da177e4c Linux-2.6.12-rc2 |
3673 3674 3675 |
putname(from); return error; } |
3480b2574 [CVE-2009-0029] S... |
3676 |
SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newname) |
5590ff0d5 [PATCH] vfs: *at ... |
3677 3678 3679 |
{ return sys_symlinkat(oldname, AT_FDCWD, newname); } |
146a8595c locks: break dele... |
3680 3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694 3695 3696 3697 3698 3699 |
/** * vfs_link - create a new link * @old_dentry: object to be linked * @dir: new parent * @new_dentry: where to create the new link * @delegated_inode: returns inode needing a delegation break * * The caller must hold dir->i_mutex * * If vfs_link discovers a delegation on the to-be-linked file in need * of breaking, it will return -EWOULDBLOCK and return a reference to the * inode in delegated_inode. The caller should then break the delegation * and retry. Because breaking a delegation may take a long time, the * caller should drop the i_mutex before doing so. * * Alternatively, a caller may pass NULL for delegated_inode. This may * be appropriate for callers that expect the underlying filesystem not * to be NFS exported. */ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry, struct inode **delegated_inode) |
1da177e4c Linux-2.6.12-rc2 |
3700 3701 |
{ struct inode *inode = old_dentry->d_inode; |
8de527787 vfs: check i_nlin... |
3702 |
unsigned max_links = dir->i_sb->s_max_links; |
1da177e4c Linux-2.6.12-rc2 |
3703 3704 3705 3706 |
int error; if (!inode) return -ENOENT; |
a95164d97 [patch 3/4] vfs: ... |
3707 |
error = may_create(dir, new_dentry); |
1da177e4c Linux-2.6.12-rc2 |
3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 |
if (error) return error; if (dir->i_sb != inode->i_sb) return -EXDEV; /* * A link to an append-only or immutable file cannot be created. */ if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) return -EPERM; |
acfa4380e inode->i_op is ne... |
3719 |
if (!dir->i_op->link) |
1da177e4c Linux-2.6.12-rc2 |
3720 |
return -EPERM; |
7e79eedb3 [patch 4/5] vfs: ... |
3721 |
if (S_ISDIR(inode->i_mode)) |
1da177e4c Linux-2.6.12-rc2 |
3722 3723 3724 3725 3726 |
return -EPERM; error = security_inode_link(old_dentry, dir, new_dentry); if (error) return error; |
7e79eedb3 [patch 4/5] vfs: ... |
3727 |
mutex_lock(&inode->i_mutex); |
aae8a97d3 fs: Don't allow t... |
3728 |
/* Make sure we don't allow creating hardlink to an unlinked file */ |
f4e0c30c1 allow the temp fi... |
3729 |
if (inode->i_nlink == 0 && !(inode->i_state & I_LINKABLE)) |
aae8a97d3 fs: Don't allow t... |
3730 |
error = -ENOENT; |
8de527787 vfs: check i_nlin... |
3731 3732 |
else if (max_links && inode->i_nlink >= max_links) error = -EMLINK; |
146a8595c locks: break dele... |
3733 3734 3735 3736 3737 |
else { error = try_break_deleg(inode, delegated_inode); if (!error) error = dir->i_op->link(old_dentry, dir, new_dentry); } |
f4e0c30c1 allow the temp fi... |
3738 3739 3740 3741 3742 3743 |
if (!error && (inode->i_state & I_LINKABLE)) { spin_lock(&inode->i_lock); inode->i_state &= ~I_LINKABLE; spin_unlock(&inode->i_lock); } |
7e79eedb3 [patch 4/5] vfs: ... |
3744 |
mutex_unlock(&inode->i_mutex); |
e31e14ec3 [PATCH] remove th... |
3745 |
if (!error) |
7e79eedb3 [patch 4/5] vfs: ... |
3746 |
fsnotify_link(dir, inode, new_dentry); |
1da177e4c Linux-2.6.12-rc2 |
3747 3748 |
return error; } |
4d3595073 namei.c: move EXP... |
3749 |
EXPORT_SYMBOL(vfs_link); |
1da177e4c Linux-2.6.12-rc2 |
3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 |
/* * Hardlinks are often used in delicate situations. We avoid * security-related surprises by not following symlinks on the * newname. --KAB * * We don't follow them on the oldname either to be compatible * with linux 2.0, and to avoid hard-linking to directories * and other special files. --ADM */ |
2e4d0924e [CVE-2009-0029] S... |
3760 3761 |
SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname, int, newdfd, const char __user *, newname, int, flags) |
1da177e4c Linux-2.6.12-rc2 |
3762 3763 |
{ struct dentry *new_dentry; |
dae6ad8f3 new helpers: kern... |
3764 |
struct path old_path, new_path; |
146a8595c locks: break dele... |
3765 |
struct inode *delegated_inode = NULL; |
11a7b371b fs: allow AT_EMPT... |
3766 |
int how = 0; |
1da177e4c Linux-2.6.12-rc2 |
3767 |
int error; |
1da177e4c Linux-2.6.12-rc2 |
3768 |
|
11a7b371b fs: allow AT_EMPT... |
3769 |
if ((flags & ~(AT_SYMLINK_FOLLOW | AT_EMPTY_PATH)) != 0) |
c04030e16 [PATCH] flags par... |
3770 |
return -EINVAL; |
11a7b371b fs: allow AT_EMPT... |
3771 |
/* |
f0cc6ffb8 Revert "fs: Allow... |
3772 3773 3774 |
* To use null names we require CAP_DAC_READ_SEARCH * This ensures that not everyone will be able to create * handlink using the passed filedescriptor. |
11a7b371b fs: allow AT_EMPT... |
3775 |
*/ |
f0cc6ffb8 Revert "fs: Allow... |
3776 3777 3778 |
if (flags & AT_EMPTY_PATH) { if (!capable(CAP_DAC_READ_SEARCH)) return -ENOENT; |
11a7b371b fs: allow AT_EMPT... |
3779 |
how = LOOKUP_EMPTY; |
f0cc6ffb8 Revert "fs: Allow... |
3780 |
} |
11a7b371b fs: allow AT_EMPT... |
3781 3782 3783 |
if (flags & AT_SYMLINK_FOLLOW) how |= LOOKUP_FOLLOW; |
442e31ca5 vfs: fix linkat t... |
3784 |
retry: |
11a7b371b fs: allow AT_EMPT... |
3785 |
error = user_path_at(olddfd, oldname, how, &old_path); |
1da177e4c Linux-2.6.12-rc2 |
3786 |
if (error) |
2ad94ae65 [PATCH] new (loca... |
3787 |
return error; |
442e31ca5 vfs: fix linkat t... |
3788 3789 |
new_dentry = user_path_create(newdfd, newname, &new_path, (how & LOOKUP_REVAL)); |
1da177e4c Linux-2.6.12-rc2 |
3790 |
error = PTR_ERR(new_dentry); |
6902d925d [PATCH] r/o bind ... |
3791 |
if (IS_ERR(new_dentry)) |
dae6ad8f3 new helpers: kern... |
3792 3793 3794 3795 3796 |
goto out; error = -EXDEV; if (old_path.mnt != new_path.mnt) goto out_dput; |
800179c9b fs: add link rest... |
3797 3798 3799 |
error = may_linkat(&old_path); if (unlikely(error)) goto out_dput; |
dae6ad8f3 new helpers: kern... |
3800 |
error = security_path_link(old_path.dentry, &new_path, new_dentry); |
be6d3e56a introduce new LSM... |
3801 |
if (error) |
a8104a9fc pull mnt_want_wri... |
3802 |
goto out_dput; |
146a8595c locks: break dele... |
3803 |
error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry, &delegated_inode); |
75c3f29de [PATCH] r/o bind ... |
3804 |
out_dput: |
921a1650d new helper: done_... |
3805 |
done_path_create(&new_path, new_dentry); |
146a8595c locks: break dele... |
3806 3807 |
if (delegated_inode) { error = break_deleg_wait(&delegated_inode); |
d22e6338d Fix mountpoint re... |
3808 3809 |
if (!error) { path_put(&old_path); |
146a8595c locks: break dele... |
3810 |
goto retry; |
d22e6338d Fix mountpoint re... |
3811 |
} |
146a8595c locks: break dele... |
3812 |
} |
442e31ca5 vfs: fix linkat t... |
3813 |
if (retry_estale(error, how)) { |
d22e6338d Fix mountpoint re... |
3814 |
path_put(&old_path); |
442e31ca5 vfs: fix linkat t... |
3815 3816 3817 |
how |= LOOKUP_REVAL; goto retry; } |
1da177e4c Linux-2.6.12-rc2 |
3818 |
out: |
2d8f30380 [PATCH] sanitize ... |
3819 |
path_put(&old_path); |
1da177e4c Linux-2.6.12-rc2 |
3820 3821 3822 |
return error; } |
3480b2574 [CVE-2009-0029] S... |
3823 |
SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname) |
5590ff0d5 [PATCH] vfs: *at ... |
3824 |
{ |
c04030e16 [PATCH] flags par... |
3825 |
return sys_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0); |
5590ff0d5 [PATCH] vfs: *at ... |
3826 |
} |
bc27027a7 vfs: rename: use ... |
3827 3828 3829 3830 3831 3832 3833 |
/** * vfs_rename - rename a filesystem object * @old_dir: parent of source * @old_dentry: source * @new_dir: parent of destination * @new_dentry: destination * @delegated_inode: returns an inode needing a delegation break |
520c8b165 vfs: add renameat... |
3834 |
* @flags: rename flags |
bc27027a7 vfs: rename: use ... |
3835 3836 3837 3838 3839 3840 3841 3842 3843 3844 3845 3846 3847 3848 |
* * The caller must hold multiple mutexes--see lock_rename()). * * If vfs_rename discovers a delegation in need of breaking at either * the source or destination, it will return -EWOULDBLOCK and return a * reference to the inode in delegated_inode. The caller should then * break the delegation and retry. Because breaking a delegation may * take a long time, the caller should drop all locks before doing * so. * * Alternatively, a caller may pass NULL for delegated_inode. This may * be appropriate for callers that expect the underlying filesystem not * to be NFS exported. * |
1da177e4c Linux-2.6.12-rc2 |
3849 3850 3851 |
* The worst of all namespace operations - renaming directory. "Perverted" * doesn't even start to describe it. Somebody in UCB had a heck of a trip... * Problems: |
d03b29a27 namei: trivial fi... |
3852 |
* a) we can get into loop creation. |
1da177e4c Linux-2.6.12-rc2 |
3853 3854 |
* b) race potential - two innocent renames can create a loop together. * That's where 4.4 screws up. Current fix: serialization on |
a11f3a057 [PATCH] sem2mutex... |
3855 |
* sb->s_vfs_rename_mutex. We might be more accurate, but that's another |
1da177e4c Linux-2.6.12-rc2 |
3856 |
* story. |
6cedba896 vfs: take i_mutex... |
3857 3858 |
* c) we have to lock _four_ objects - parents and victim (if it exists), * and source (if it is not a directory). |
1b1dcc1b5 [PATCH] mutex sub... |
3859 |
* And that - after we got ->i_mutex on parents (until then we don't know |
1da177e4c Linux-2.6.12-rc2 |
3860 3861 |
* whether the target exists). Solution: try to be smart with locking * order for inodes. We rely on the fact that tree topology may change |
a11f3a057 [PATCH] sem2mutex... |
3862 |
* only under ->s_vfs_rename_mutex _and_ that parent of the object we |
1da177e4c Linux-2.6.12-rc2 |
3863 3864 3865 |
* move will be locked. Thus we can rank directories by the tree * (ancestors first) and rank all non-directories after them. * That works since everybody except rename does "lock parent, lookup, |
a11f3a057 [PATCH] sem2mutex... |
3866 |
* lock child" and rename is under ->s_vfs_rename_mutex. |
1da177e4c Linux-2.6.12-rc2 |
3867 3868 3869 |
* HOWEVER, it relies on the assumption that any object with ->lookup() * has no more than 1 dentry. If "hybrid" objects will ever appear, * we'd better make sure that there's no link(2) for them. |
e4eaac06b vfs: push dentry_... |
3870 |
* d) conversion from fhandle to dentry may come in the wrong moment - when |
1b1dcc1b5 [PATCH] mutex sub... |
3871 |
* we are removing the target. Solution: we will have to grab ->i_mutex |
1da177e4c Linux-2.6.12-rc2 |
3872 |
* in the fhandle_to_dentry code. [FIXME - current nfsfh.c relies on |
c41b20e72 Fix misspellings ... |
3873 |
* ->i_mutex on parents, which works but leads to some truly excessive |
1da177e4c Linux-2.6.12-rc2 |
3874 3875 |
* locking]. */ |
bc27027a7 vfs: rename: use ... |
3876 3877 |
int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, |
520c8b165 vfs: add renameat... |
3878 |
struct inode **delegated_inode, unsigned int flags) |
1da177e4c Linux-2.6.12-rc2 |
3879 |
{ |
bc27027a7 vfs: rename: use ... |
3880 3881 3882 3883 |
int error; bool is_dir = d_is_dir(old_dentry); const unsigned char *old_name; struct inode *source = old_dentry->d_inode; |
9055cba71 vfs: clean up vfs... |
3884 |
struct inode *target = new_dentry->d_inode; |
da1ce0670 vfs: add cross-re... |
3885 3886 |
bool new_is_dir = false; unsigned max_links = new_dir->i_sb->s_max_links; |
bc27027a7 vfs: rename: use ... |
3887 3888 3889 3890 3891 3892 3893 |
if (source == target) return 0; error = may_delete(old_dir, old_dentry, is_dir); if (error) return error; |
da1ce0670 vfs: add cross-re... |
3894 |
if (!target) { |
bc27027a7 vfs: rename: use ... |
3895 |
error = may_create(new_dir, new_dentry); |
da1ce0670 vfs: add cross-re... |
3896 3897 3898 3899 3900 3901 3902 3903 |
} else { new_is_dir = d_is_dir(new_dentry); if (!(flags & RENAME_EXCHANGE)) error = may_delete(new_dir, new_dentry, is_dir); else error = may_delete(new_dir, new_dentry, new_is_dir); } |
bc27027a7 vfs: rename: use ... |
3904 3905 |
if (error) return error; |
7177a9c4b fs: call rename2 ... |
3906 |
if (!old_dir->i_op->rename && !old_dir->i_op->rename2) |
bc27027a7 vfs: rename: use ... |
3907 |
return -EPERM; |
1da177e4c Linux-2.6.12-rc2 |
3908 |
|
520c8b165 vfs: add renameat... |
3909 3910 |
if (flags && !old_dir->i_op->rename2) return -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
3911 3912 3913 3914 |
/* * If we are going to change the parent - check write permissions, * we'll need to flip '..'. */ |
da1ce0670 vfs: add cross-re... |
3915 3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 |
if (new_dir != old_dir) { if (is_dir) { error = inode_permission(source, MAY_WRITE); if (error) return error; } if ((flags & RENAME_EXCHANGE) && new_is_dir) { error = inode_permission(target, MAY_WRITE); if (error) return error; } |
1da177e4c Linux-2.6.12-rc2 |
3926 |
} |
0b3974eb0 security: add fla... |
3927 3928 |
error = security_inode_rename(old_dir, old_dentry, new_dir, new_dentry, flags); |
1da177e4c Linux-2.6.12-rc2 |
3929 3930 |
if (error) return error; |
bc27027a7 vfs: rename: use ... |
3931 |
old_name = fsnotify_oldname_init(old_dentry->d_name.name); |
1d2ef5901 restore pinning t... |
3932 |
dget(new_dentry); |
da1ce0670 vfs: add cross-re... |
3933 |
if (!is_dir || (flags & RENAME_EXCHANGE)) |
bc27027a7 vfs: rename: use ... |
3934 3935 |
lock_two_nondirectories(source, target); else if (target) |
1b1dcc1b5 [PATCH] mutex sub... |
3936 |
mutex_lock(&target->i_mutex); |
9055cba71 vfs: clean up vfs... |
3937 3938 3939 3940 |
error = -EBUSY; if (d_mountpoint(old_dentry) || d_mountpoint(new_dentry)) goto out; |
da1ce0670 vfs: add cross-re... |
3941 |
if (max_links && new_dir != old_dir) { |
bc27027a7 vfs: rename: use ... |
3942 |
error = -EMLINK; |
da1ce0670 vfs: add cross-re... |
3943 |
if (is_dir && !new_is_dir && new_dir->i_nlink >= max_links) |
bc27027a7 vfs: rename: use ... |
3944 |
goto out; |
da1ce0670 vfs: add cross-re... |
3945 3946 3947 3948 3949 3950 3951 |
if ((flags & RENAME_EXCHANGE) && !is_dir && new_is_dir && old_dir->i_nlink >= max_links) goto out; } if (is_dir && !(flags & RENAME_EXCHANGE) && target) shrink_dcache_parent(new_dentry); if (!is_dir) { |
bc27027a7 vfs: rename: use ... |
3952 |
error = try_break_deleg(source, delegated_inode); |
8e6d782ca locks: break dele... |
3953 3954 |
if (error) goto out; |
da1ce0670 vfs: add cross-re... |
3955 3956 3957 3958 3959 |
} if (target && !new_is_dir) { error = try_break_deleg(target, delegated_inode); if (error) goto out; |
8e6d782ca locks: break dele... |
3960 |
} |
7177a9c4b fs: call rename2 ... |
3961 |
if (!old_dir->i_op->rename2) { |
520c8b165 vfs: add renameat... |
3962 3963 3964 |
error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry); } else { |
7177a9c4b fs: call rename2 ... |
3965 |
WARN_ON(old_dir->i_op->rename != NULL); |
520c8b165 vfs: add renameat... |
3966 3967 3968 |
error = old_dir->i_op->rename2(old_dir, old_dentry, new_dir, new_dentry, flags); } |
51892bbb5 vfs: clean up vfs... |
3969 3970 |
if (error) goto out; |
da1ce0670 vfs: add cross-re... |
3971 |
if (!(flags & RENAME_EXCHANGE) && target) { |
bc27027a7 vfs: rename: use ... |
3972 3973 |
if (is_dir) target->i_flags |= S_DEAD; |
51892bbb5 vfs: clean up vfs... |
3974 |
dont_mount(new_dentry); |
bc27027a7 vfs: rename: use ... |
3975 |
} |
da1ce0670 vfs: add cross-re... |
3976 3977 3978 3979 3980 3981 |
if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE)) { if (!(flags & RENAME_EXCHANGE)) d_move(old_dentry, new_dentry); else d_exchange(old_dentry, new_dentry); } |
51892bbb5 vfs: clean up vfs... |
3982 |
out: |
da1ce0670 vfs: add cross-re... |
3983 |
if (!is_dir || (flags & RENAME_EXCHANGE)) |
bc27027a7 vfs: rename: use ... |
3984 3985 3986 |
unlock_two_nondirectories(source, target); else if (target) mutex_unlock(&target->i_mutex); |
1da177e4c Linux-2.6.12-rc2 |
3987 |
dput(new_dentry); |
da1ce0670 vfs: add cross-re... |
3988 |
if (!error) { |
123df2944 Lose the new_name... |
3989 |
fsnotify_move(old_dir, new_dir, old_name, is_dir, |
da1ce0670 vfs: add cross-re... |
3990 3991 3992 3993 3994 3995 |
!(flags & RENAME_EXCHANGE) ? target : NULL, old_dentry); if (flags & RENAME_EXCHANGE) { fsnotify_move(new_dir, old_dir, old_dentry->d_name.name, new_is_dir, NULL, new_dentry); } } |
0eeca2830 [PATCH] inotify |
3996 |
fsnotify_oldname_free(old_name); |
1da177e4c Linux-2.6.12-rc2 |
3997 3998 |
return error; } |
4d3595073 namei.c: move EXP... |
3999 |
EXPORT_SYMBOL(vfs_rename); |
1da177e4c Linux-2.6.12-rc2 |
4000 |
|
520c8b165 vfs: add renameat... |
4001 4002 |
SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname, int, newdfd, const char __user *, newname, unsigned int, flags) |
1da177e4c Linux-2.6.12-rc2 |
4003 |
{ |
2ad94ae65 [PATCH] new (loca... |
4004 4005 4006 |
struct dentry *old_dir, *new_dir; struct dentry *old_dentry, *new_dentry; struct dentry *trap; |
1da177e4c Linux-2.6.12-rc2 |
4007 |
struct nameidata oldnd, newnd; |
8e6d782ca locks: break dele... |
4008 |
struct inode *delegated_inode = NULL; |
91a27b2a7 vfs: define struc... |
4009 4010 |
struct filename *from; struct filename *to; |
c6a942840 vfs: fix renameat... |
4011 4012 |
unsigned int lookup_flags = 0; bool should_retry = false; |
2ad94ae65 [PATCH] new (loca... |
4013 |
int error; |
520c8b165 vfs: add renameat... |
4014 |
|
da1ce0670 vfs: add cross-re... |
4015 4016 4017 4018 |
if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE)) return -EINVAL; if ((flags & RENAME_NOREPLACE) && (flags & RENAME_EXCHANGE)) |
520c8b165 vfs: add renameat... |
4019 |
return -EINVAL; |
c6a942840 vfs: fix renameat... |
4020 4021 |
retry: from = user_path_parent(olddfd, oldname, &oldnd, lookup_flags); |
91a27b2a7 vfs: define struc... |
4022 4023 |
if (IS_ERR(from)) { error = PTR_ERR(from); |
1da177e4c Linux-2.6.12-rc2 |
4024 |
goto exit; |
91a27b2a7 vfs: define struc... |
4025 |
} |
1da177e4c Linux-2.6.12-rc2 |
4026 |
|
c6a942840 vfs: fix renameat... |
4027 |
to = user_path_parent(newdfd, newname, &newnd, lookup_flags); |
91a27b2a7 vfs: define struc... |
4028 4029 |
if (IS_ERR(to)) { error = PTR_ERR(to); |
1da177e4c Linux-2.6.12-rc2 |
4030 |
goto exit1; |
91a27b2a7 vfs: define struc... |
4031 |
} |
1da177e4c Linux-2.6.12-rc2 |
4032 4033 |
error = -EXDEV; |
4ac913785 Embed a struct pa... |
4034 |
if (oldnd.path.mnt != newnd.path.mnt) |
1da177e4c Linux-2.6.12-rc2 |
4035 |
goto exit2; |
4ac913785 Embed a struct pa... |
4036 |
old_dir = oldnd.path.dentry; |
1da177e4c Linux-2.6.12-rc2 |
4037 4038 4039 |
error = -EBUSY; if (oldnd.last_type != LAST_NORM) goto exit2; |
4ac913785 Embed a struct pa... |
4040 |
new_dir = newnd.path.dentry; |
0a7c3937a vfs: add RENAME_N... |
4041 4042 |
if (flags & RENAME_NOREPLACE) error = -EEXIST; |
1da177e4c Linux-2.6.12-rc2 |
4043 4044 |
if (newnd.last_type != LAST_NORM) goto exit2; |
c30dabfe5 fs: Push mnt_want... |
4045 4046 4047 |
error = mnt_want_write(oldnd.path.mnt); if (error) goto exit2; |
0612d9fb2 [PATCH vfs-2.6 5/... |
4048 4049 |
oldnd.flags &= ~LOOKUP_PARENT; newnd.flags &= ~LOOKUP_PARENT; |
da1ce0670 vfs: add cross-re... |
4050 4051 |
if (!(flags & RENAME_EXCHANGE)) newnd.flags |= LOOKUP_RENAME_TARGET; |
0612d9fb2 [PATCH vfs-2.6 5/... |
4052 |
|
8e6d782ca locks: break dele... |
4053 |
retry_deleg: |
1da177e4c Linux-2.6.12-rc2 |
4054 |
trap = lock_rename(new_dir, old_dir); |
49705b774 [PATCH] sanitize ... |
4055 |
old_dentry = lookup_hash(&oldnd); |
1da177e4c Linux-2.6.12-rc2 |
4056 4057 4058 4059 4060 |
error = PTR_ERR(old_dentry); if (IS_ERR(old_dentry)) goto exit3; /* source must exist */ error = -ENOENT; |
b18825a7c VFS: Put a small ... |
4061 |
if (d_is_negative(old_dentry)) |
1da177e4c Linux-2.6.12-rc2 |
4062 |
goto exit4; |
0a7c3937a vfs: add RENAME_N... |
4063 4064 4065 4066 4067 4068 4069 |
new_dentry = lookup_hash(&newnd); error = PTR_ERR(new_dentry); if (IS_ERR(new_dentry)) goto exit4; error = -EEXIST; if ((flags & RENAME_NOREPLACE) && d_is_positive(new_dentry)) goto exit5; |
da1ce0670 vfs: add cross-re... |
4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 |
if (flags & RENAME_EXCHANGE) { error = -ENOENT; if (d_is_negative(new_dentry)) goto exit5; if (!d_is_dir(new_dentry)) { error = -ENOTDIR; if (newnd.last.name[newnd.last.len]) goto exit5; } } |
1da177e4c Linux-2.6.12-rc2 |
4081 |
/* unless the source is a directory trailing slashes give -ENOTDIR */ |
44b1d5304 vfs: add d_is_dir() |
4082 |
if (!d_is_dir(old_dentry)) { |
1da177e4c Linux-2.6.12-rc2 |
4083 4084 |
error = -ENOTDIR; if (oldnd.last.name[oldnd.last.len]) |
0a7c3937a vfs: add RENAME_N... |
4085 |
goto exit5; |
da1ce0670 vfs: add cross-re... |
4086 |
if (!(flags & RENAME_EXCHANGE) && newnd.last.name[newnd.last.len]) |
0a7c3937a vfs: add RENAME_N... |
4087 |
goto exit5; |
1da177e4c Linux-2.6.12-rc2 |
4088 4089 4090 4091 |
} /* source should not be ancestor of target */ error = -EINVAL; if (old_dentry == trap) |
0a7c3937a vfs: add RENAME_N... |
4092 |
goto exit5; |
1da177e4c Linux-2.6.12-rc2 |
4093 |
/* target should not be an ancestor of source */ |
da1ce0670 vfs: add cross-re... |
4094 4095 |
if (!(flags & RENAME_EXCHANGE)) error = -ENOTEMPTY; |
1da177e4c Linux-2.6.12-rc2 |
4096 4097 |
if (new_dentry == trap) goto exit5; |
be6d3e56a introduce new LSM... |
4098 |
error = security_path_rename(&oldnd.path, old_dentry, |
0b3974eb0 security: add fla... |
4099 |
&newnd.path, new_dentry, flags); |
be6d3e56a introduce new LSM... |
4100 |
if (error) |
c30dabfe5 fs: Push mnt_want... |
4101 |
goto exit5; |
1da177e4c Linux-2.6.12-rc2 |
4102 |
error = vfs_rename(old_dir->d_inode, old_dentry, |
520c8b165 vfs: add renameat... |
4103 4104 |
new_dir->d_inode, new_dentry, &delegated_inode, flags); |
1da177e4c Linux-2.6.12-rc2 |
4105 4106 4107 4108 4109 4110 |
exit5: dput(new_dentry); exit4: dput(old_dentry); exit3: unlock_rename(new_dir, old_dir); |
8e6d782ca locks: break dele... |
4111 4112 4113 4114 4115 |
if (delegated_inode) { error = break_deleg_wait(&delegated_inode); if (!error) goto retry_deleg; } |
c30dabfe5 fs: Push mnt_want... |
4116 |
mnt_drop_write(oldnd.path.mnt); |
1da177e4c Linux-2.6.12-rc2 |
4117 |
exit2: |
c6a942840 vfs: fix renameat... |
4118 4119 |
if (retry_estale(error, lookup_flags)) should_retry = true; |
1d957f9bf Introduce path_put() |
4120 |
path_put(&newnd.path); |
2ad94ae65 [PATCH] new (loca... |
4121 |
putname(to); |
1da177e4c Linux-2.6.12-rc2 |
4122 |
exit1: |
1d957f9bf Introduce path_put() |
4123 |
path_put(&oldnd.path); |
1da177e4c Linux-2.6.12-rc2 |
4124 |
putname(from); |
c6a942840 vfs: fix renameat... |
4125 4126 4127 4128 4129 |
if (should_retry) { should_retry = false; lookup_flags |= LOOKUP_REVAL; goto retry; } |
2ad94ae65 [PATCH] new (loca... |
4130 |
exit: |
1da177e4c Linux-2.6.12-rc2 |
4131 4132 |
return error; } |
520c8b165 vfs: add renameat... |
4133 4134 4135 4136 4137 |
SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname, int, newdfd, const char __user *, newname) { return sys_renameat2(olddfd, oldname, newdfd, newname, 0); } |
a26eab240 [CVE-2009-0029] S... |
4138 |
SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newname) |
5590ff0d5 [PATCH] vfs: *at ... |
4139 |
{ |
520c8b165 vfs: add renameat... |
4140 |
return sys_renameat2(AT_FDCWD, oldname, AT_FDCWD, newname, 0); |
5590ff0d5 [PATCH] vfs: *at ... |
4141 |
} |
5d826c847 new helper: readl... |
4142 |
int readlink_copy(char __user *buffer, int buflen, const char *link) |
1da177e4c Linux-2.6.12-rc2 |
4143 |
{ |
5d826c847 new helper: readl... |
4144 |
int len = PTR_ERR(link); |
1da177e4c Linux-2.6.12-rc2 |
4145 4146 4147 4148 4149 4150 4151 4152 4153 4154 4155 |
if (IS_ERR(link)) goto out; len = strlen(link); if (len > (unsigned) buflen) len = buflen; if (copy_to_user(buffer, link, len)) len = -EFAULT; out: return len; } |
5d826c847 new helper: readl... |
4156 |
EXPORT_SYMBOL(readlink_copy); |
1da177e4c Linux-2.6.12-rc2 |
4157 4158 4159 4160 4161 4162 4163 4164 4165 |
/* * A helper for ->readlink(). This should be used *ONLY* for symlinks that * have ->follow_link() touching nd only in nd_set_link(). Using (or not * using) it for any given inode is up to filesystem. */ int generic_readlink(struct dentry *dentry, char __user *buffer, int buflen) { struct nameidata nd; |
cc314eef0 Fix nasty ncpfs s... |
4166 |
void *cookie; |
694a1764d [patch 3/4] vfs: ... |
4167 |
int res; |
cc314eef0 Fix nasty ncpfs s... |
4168 |
|
1da177e4c Linux-2.6.12-rc2 |
4169 |
nd.depth = 0; |
cc314eef0 Fix nasty ncpfs s... |
4170 |
cookie = dentry->d_inode->i_op->follow_link(dentry, &nd); |
694a1764d [patch 3/4] vfs: ... |
4171 4172 |
if (IS_ERR(cookie)) return PTR_ERR(cookie); |
5d826c847 new helper: readl... |
4173 |
res = readlink_copy(buffer, buflen, nd_get_link(&nd)); |
694a1764d [patch 3/4] vfs: ... |
4174 4175 4176 |
if (dentry->d_inode->i_op->put_link) dentry->d_inode->i_op->put_link(dentry, &nd, cookie); return res; |
1da177e4c Linux-2.6.12-rc2 |
4177 |
} |
4d3595073 namei.c: move EXP... |
4178 |
EXPORT_SYMBOL(generic_readlink); |
1da177e4c Linux-2.6.12-rc2 |
4179 |
|
1da177e4c Linux-2.6.12-rc2 |
4180 4181 4182 |
/* get the link contents into pagecache */ static char *page_getlink(struct dentry * dentry, struct page **ppage) { |
ebd09abbd vfs: ensure page ... |
4183 4184 |
char *kaddr; struct page *page; |
1da177e4c Linux-2.6.12-rc2 |
4185 |
struct address_space *mapping = dentry->d_inode->i_mapping; |
090d2b185 [PATCH] read_mapp... |
4186 |
page = read_mapping_page(mapping, 0, NULL); |
1da177e4c Linux-2.6.12-rc2 |
4187 |
if (IS_ERR(page)) |
6fe6900e1 mm: make read_cac... |
4188 |
return (char*)page; |
1da177e4c Linux-2.6.12-rc2 |
4189 |
*ppage = page; |
ebd09abbd vfs: ensure page ... |
4190 4191 4192 |
kaddr = kmap(page); nd_terminate_link(kaddr, dentry->d_inode->i_size, PAGE_SIZE - 1); return kaddr; |
1da177e4c Linux-2.6.12-rc2 |
4193 4194 4195 4196 4197 |
} int page_readlink(struct dentry *dentry, char __user *buffer, int buflen) { struct page *page = NULL; |
5d826c847 new helper: readl... |
4198 |
int res = readlink_copy(buffer, buflen, page_getlink(dentry, &page)); |
1da177e4c Linux-2.6.12-rc2 |
4199 4200 4201 4202 4203 4204 |
if (page) { kunmap(page); page_cache_release(page); } return res; } |
4d3595073 namei.c: move EXP... |
4205 |
EXPORT_SYMBOL(page_readlink); |
1da177e4c Linux-2.6.12-rc2 |
4206 |
|
cc314eef0 Fix nasty ncpfs s... |
4207 |
void *page_follow_link_light(struct dentry *dentry, struct nameidata *nd) |
1da177e4c Linux-2.6.12-rc2 |
4208 |
{ |
cc314eef0 Fix nasty ncpfs s... |
4209 |
struct page *page = NULL; |
1da177e4c Linux-2.6.12-rc2 |
4210 |
nd_set_link(nd, page_getlink(dentry, &page)); |
cc314eef0 Fix nasty ncpfs s... |
4211 |
return page; |
1da177e4c Linux-2.6.12-rc2 |
4212 |
} |
4d3595073 namei.c: move EXP... |
4213 |
EXPORT_SYMBOL(page_follow_link_light); |
1da177e4c Linux-2.6.12-rc2 |
4214 |
|
cc314eef0 Fix nasty ncpfs s... |
4215 |
void page_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie) |
1da177e4c Linux-2.6.12-rc2 |
4216 |
{ |
cc314eef0 Fix nasty ncpfs s... |
4217 4218 4219 |
struct page *page = cookie; if (page) { |
1da177e4c Linux-2.6.12-rc2 |
4220 4221 |
kunmap(page); page_cache_release(page); |
1da177e4c Linux-2.6.12-rc2 |
4222 4223 |
} } |
4d3595073 namei.c: move EXP... |
4224 |
EXPORT_SYMBOL(page_put_link); |
1da177e4c Linux-2.6.12-rc2 |
4225 |
|
54566b2c1 fs: symlink write... |
4226 4227 4228 4229 |
/* * The nofs argument instructs pagecache_write_begin to pass AOP_FLAG_NOFS */ int __page_symlink(struct inode *inode, const char *symname, int len, int nofs) |
1da177e4c Linux-2.6.12-rc2 |
4230 4231 |
{ struct address_space *mapping = inode->i_mapping; |
0adb25d2e [PATCH] ext3: ext... |
4232 |
struct page *page; |
afddba49d fs: introduce wri... |
4233 |
void *fsdata; |
beb497ab4 [PATCH] __page_sy... |
4234 |
int err; |
1da177e4c Linux-2.6.12-rc2 |
4235 |
char *kaddr; |
54566b2c1 fs: symlink write... |
4236 4237 4238 |
unsigned int flags = AOP_FLAG_UNINTERRUPTIBLE; if (nofs) flags |= AOP_FLAG_NOFS; |
1da177e4c Linux-2.6.12-rc2 |
4239 |
|
7e53cac41 [PATCH] Honour AO... |
4240 |
retry: |
afddba49d fs: introduce wri... |
4241 |
err = pagecache_write_begin(NULL, mapping, 0, len-1, |
54566b2c1 fs: symlink write... |
4242 |
flags, &page, &fsdata); |
1da177e4c Linux-2.6.12-rc2 |
4243 |
if (err) |
afddba49d fs: introduce wri... |
4244 |
goto fail; |
e8e3c3d66 fs: remove the se... |
4245 |
kaddr = kmap_atomic(page); |
1da177e4c Linux-2.6.12-rc2 |
4246 |
memcpy(kaddr, symname, len-1); |
e8e3c3d66 fs: remove the se... |
4247 |
kunmap_atomic(kaddr); |
afddba49d fs: introduce wri... |
4248 4249 4250 |
err = pagecache_write_end(NULL, mapping, 0, len-1, len-1, page, fsdata); |
1da177e4c Linux-2.6.12-rc2 |
4251 4252 |
if (err < 0) goto fail; |
afddba49d fs: introduce wri... |
4253 4254 |
if (err < len-1) goto retry; |
1da177e4c Linux-2.6.12-rc2 |
4255 4256 |
mark_inode_dirty(inode); return 0; |
1da177e4c Linux-2.6.12-rc2 |
4257 4258 4259 |
fail: return err; } |
4d3595073 namei.c: move EXP... |
4260 |
EXPORT_SYMBOL(__page_symlink); |
1da177e4c Linux-2.6.12-rc2 |
4261 |
|
0adb25d2e [PATCH] ext3: ext... |
4262 4263 4264 |
int page_symlink(struct inode *inode, const char *symname, int len) { return __page_symlink(inode, symname, len, |
54566b2c1 fs: symlink write... |
4265 |
!(mapping_gfp_mask(inode->i_mapping) & __GFP_FS)); |
0adb25d2e [PATCH] ext3: ext... |
4266 |
} |
4d3595073 namei.c: move EXP... |
4267 |
EXPORT_SYMBOL(page_symlink); |
0adb25d2e [PATCH] ext3: ext... |
4268 |
|
92e1d5be9 [PATCH] mark stru... |
4269 |
const struct inode_operations page_symlink_inode_operations = { |
1da177e4c Linux-2.6.12-rc2 |
4270 4271 4272 4273 |
.readlink = generic_readlink, .follow_link = page_follow_link_light, .put_link = page_put_link, }; |
1da177e4c Linux-2.6.12-rc2 |
4274 |
EXPORT_SYMBOL(page_symlink_inode_operations); |