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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 (inode_capable(inode, CAP_DAC_OVERRIDE)) |
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return 0; if (!(mask & MAY_WRITE)) |
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if (inode_capable(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 (inode_capable(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 (inode_capable(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. |
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478 |
*/ |
31e6b01f4 fs: rcu-walk for ... |
479 480 |
/** |
19660af73 consolidate namei... |
481 482 483 |
* 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... |
484 |
* Returns: 0 on success, -ECHILD on failure |
31e6b01f4 fs: rcu-walk for ... |
485 |
* |
19660af73 consolidate namei... |
486 487 488 |
* 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 ... |
489 |
*/ |
19660af73 consolidate namei... |
490 |
static int unlazy_walk(struct nameidata *nd, struct dentry *dentry) |
31e6b01f4 fs: rcu-walk for ... |
491 492 493 494 495 |
{ struct fs_struct *fs = current->fs; struct dentry *parent = nd->path.dentry; BUG_ON(!(nd->flags & LOOKUP_RCU)); |
e5c832d55 vfs: fix dentry R... |
496 497 |
/* |
48a066e72 RCU'd vfsmounts |
498 499 500 501 502 503 |
* 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... |
504 |
*/ |
48a066e72 RCU'd vfsmounts |
505 |
if (!legitimize_mnt(nd->path.mnt, nd->m_seq)) |
e5c832d55 vfs: fix dentry R... |
506 |
return -ECHILD; |
e5c832d55 vfs: fix dentry R... |
507 |
nd->flags &= ~LOOKUP_RCU; |
15570086b vfs: reimplement ... |
508 |
|
48a066e72 RCU'd vfsmounts |
509 510 |
if (!lockref_get_not_dead(&parent->d_lockref)) { nd->path.dentry = NULL; |
d870b4a19 fix bogus path_pu... |
511 |
goto out; |
48a066e72 RCU'd vfsmounts |
512 |
} |
15570086b vfs: reimplement ... |
513 514 515 516 517 518 519 520 521 522 523 |
/* * 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... |
524 |
if (!dentry) { |
e5c832d55 vfs: fix dentry R... |
525 526 |
if (read_seqcount_retry(&parent->d_seq, nd->seq)) goto out; |
19660af73 consolidate namei... |
527 528 |
BUG_ON(nd->inode != parent->d_inode); } else { |
e5c832d55 vfs: fix dentry R... |
529 530 531 532 |
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... |
533 |
} |
e5c832d55 vfs: fix dentry R... |
534 535 536 537 538 539 540 541 542 |
/* * 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 ... |
543 544 545 |
path_get(&nd->root); spin_unlock(&fs->lock); } |
31e6b01f4 fs: rcu-walk for ... |
546 |
|
8b61e74ff get rid of {lock,... |
547 |
rcu_read_unlock(); |
31e6b01f4 fs: rcu-walk for ... |
548 |
return 0; |
19660af73 consolidate namei... |
549 |
|
e5c832d55 vfs: fix dentry R... |
550 551 552 |
unlock_and_drop_dentry: spin_unlock(&fs->lock); drop_dentry: |
8b61e74ff get rid of {lock,... |
553 |
rcu_read_unlock(); |
15570086b vfs: reimplement ... |
554 |
dput(dentry); |
d0d272771 vfs: make sure we... |
555 |
goto drop_root_mnt; |
e5c832d55 vfs: fix dentry R... |
556 |
out: |
8b61e74ff get rid of {lock,... |
557 |
rcu_read_unlock(); |
d0d272771 vfs: make sure we... |
558 559 560 |
drop_root_mnt: if (!(nd->flags & LOOKUP_ROOT)) nd->root.mnt = NULL; |
31e6b01f4 fs: rcu-walk for ... |
561 562 |
return -ECHILD; } |
4ce16ef3f fs/namei.c: don't... |
563 |
static inline int d_revalidate(struct dentry *dentry, unsigned int flags) |
34286d666 fs: rcu-walk awar... |
564 |
{ |
4ce16ef3f fs/namei.c: don't... |
565 |
return dentry->d_op->d_revalidate(dentry, flags); |
34286d666 fs: rcu-walk awar... |
566 |
} |
9f1fafee9 merge handle_reva... |
567 568 569 |
/** * complete_walk - successful completion of path walk * @nd: pointer nameidata |
39159de2a vfs: force reval ... |
570 |
* |
9f1fafee9 merge handle_reva... |
571 572 573 574 575 |
* 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 ... |
576 |
*/ |
9f1fafee9 merge handle_reva... |
577 |
static int complete_walk(struct nameidata *nd) |
39159de2a vfs: force reval ... |
578 |
{ |
16c2cd717 untangle the "nee... |
579 |
struct dentry *dentry = nd->path.dentry; |
39159de2a vfs: force reval ... |
580 |
int status; |
39159de2a vfs: force reval ... |
581 |
|
9f1fafee9 merge handle_reva... |
582 583 584 585 |
if (nd->flags & LOOKUP_RCU) { nd->flags &= ~LOOKUP_RCU; if (!(nd->flags & LOOKUP_ROOT)) nd->root.mnt = NULL; |
15570086b vfs: reimplement ... |
586 |
|
48a066e72 RCU'd vfsmounts |
587 |
if (!legitimize_mnt(nd->path.mnt, nd->m_seq)) { |
8b61e74ff get rid of {lock,... |
588 |
rcu_read_unlock(); |
48a066e72 RCU'd vfsmounts |
589 590 |
return -ECHILD; } |
e5c832d55 vfs: fix dentry R... |
591 |
if (unlikely(!lockref_get_not_dead(&dentry->d_lockref))) { |
8b61e74ff get rid of {lock,... |
592 |
rcu_read_unlock(); |
48a066e72 RCU'd vfsmounts |
593 |
mntput(nd->path.mnt); |
e5c832d55 vfs: fix dentry R... |
594 595 596 |
return -ECHILD; } if (read_seqcount_retry(&dentry->d_seq, nd->seq)) { |
8b61e74ff get rid of {lock,... |
597 |
rcu_read_unlock(); |
e5c832d55 vfs: fix dentry R... |
598 |
dput(dentry); |
48a066e72 RCU'd vfsmounts |
599 |
mntput(nd->path.mnt); |
9f1fafee9 merge handle_reva... |
600 601 |
return -ECHILD; } |
8b61e74ff get rid of {lock,... |
602 |
rcu_read_unlock(); |
9f1fafee9 merge handle_reva... |
603 |
} |
16c2cd717 untangle the "nee... |
604 605 |
if (likely(!(nd->flags & LOOKUP_JUMPED))) return 0; |
ecf3d1f1a vfs: kill FS_REVA... |
606 |
if (likely(!(dentry->d_flags & DCACHE_OP_WEAK_REVALIDATE))) |
39159de2a vfs: force reval ... |
607 |
return 0; |
ecf3d1f1a vfs: kill FS_REVA... |
608 |
status = dentry->d_op->d_weak_revalidate(dentry, nd->flags); |
39159de2a vfs: force reval ... |
609 610 |
if (status > 0) return 0; |
16c2cd717 untangle the "nee... |
611 |
if (!status) |
39159de2a vfs: force reval ... |
612 |
status = -ESTALE; |
16c2cd717 untangle the "nee... |
613 |
|
9f1fafee9 merge handle_reva... |
614 |
path_put(&nd->path); |
39159de2a vfs: force reval ... |
615 616 |
return status; } |
2a7378711 Cache root in nam... |
617 618 |
static __always_inline void set_root(struct nameidata *nd) { |
f7ad3c6be vfs: add helpers ... |
619 620 |
if (!nd->root.mnt) get_fs_root(current->fs, &nd->root); |
2a7378711 Cache root in nam... |
621 |
} |
6de88d729 kill __link_path_... |
622 |
static int link_path_walk(const char *, struct nameidata *); |
31e6b01f4 fs: rcu-walk for ... |
623 624 625 626 |
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... |
627 628 629 630 631 |
unsigned seq; do { seq = read_seqcount_begin(&fs->seq); nd->root = fs->root; |
c1530019e vfs: Fix absolute... |
632 |
nd->seq = __read_seqcount_begin(&nd->root.dentry->d_seq); |
c28cc3646 fs: fs_struct use... |
633 |
} while (read_seqcount_retry(&fs->seq, seq)); |
31e6b01f4 fs: rcu-walk for ... |
634 635 |
} } |
1d957f9bf Introduce path_put() |
636 |
static void path_put_conditional(struct path *path, struct nameidata *nd) |
051d38125 [PATCH] autofs4: ... |
637 638 |
{ dput(path->dentry); |
4ac913785 Embed a struct pa... |
639 |
if (path->mnt != nd->path.mnt) |
051d38125 [PATCH] autofs4: ... |
640 641 |
mntput(path->mnt); } |
7b9337aaf fs: namei fix ->p... |
642 643 |
static inline void path_to_nameidata(const struct path *path, struct nameidata *nd) |
051d38125 [PATCH] autofs4: ... |
644 |
{ |
31e6b01f4 fs: rcu-walk for ... |
645 646 647 648 |
if (!(nd->flags & LOOKUP_RCU)) { dput(nd->path.dentry); if (nd->path.mnt != path->mnt) mntput(nd->path.mnt); |
9a2296832 namei.c : update ... |
649 |
} |
31e6b01f4 fs: rcu-walk for ... |
650 |
nd->path.mnt = path->mnt; |
4ac913785 Embed a struct pa... |
651 |
nd->path.dentry = path->dentry; |
051d38125 [PATCH] autofs4: ... |
652 |
} |
b5fb63c18 fs: add nd_jump_link |
653 654 655 656 657 658 659 660 661 662 663 |
/* * 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 |
664 |
} |
574197e0d tidy the trailing... |
665 666 667 |
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... |
668 |
if (inode->i_op->put_link) |
574197e0d tidy the trailing... |
669 670 671 |
inode->i_op->put_link(link->dentry, nd, cookie); path_put(link); } |
561ec64ae VFS: don't do pro... |
672 673 |
int sysctl_protected_symlinks __read_mostly = 0; int sysctl_protected_hardlinks __read_mostly = 0; |
800179c9b fs: add link rest... |
674 675 676 677 |
/** * may_follow_link - Check symlink following for unsafe situations * @link: The path of the symlink |
55852635a fs: fix fs/namei.... |
678 |
* @nd: nameidata pathwalk data |
800179c9b fs: add link rest... |
679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 |
* * 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... |
701 |
if (uid_eq(current_cred()->fsuid, inode->i_uid)) |
800179c9b fs: add link rest... |
702 703 704 705 706 707 708 709 |
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... |
710 |
if (uid_eq(parent->i_uid, inode->i_uid)) |
800179c9b fs: add link rest... |
711 |
return 0; |
ffd8d101a fs: prevent use a... |
712 |
audit_log_link_denied("follow_link", link); |
800179c9b fs: add link rest... |
713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 |
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... |
779 |
if (uid_eq(cred->fsuid, inode->i_uid) || safe_hardlink_source(inode) || |
800179c9b fs: add link rest... |
780 781 |
capable(CAP_FOWNER)) return 0; |
a51d9eaa4 fs: add link rest... |
782 |
audit_log_link_denied("linkat", link); |
800179c9b fs: add link rest... |
783 784 |
return -EPERM; } |
def4af30c Get rid of symlin... |
785 |
static __always_inline int |
574197e0d tidy the trailing... |
786 |
follow_link(struct path *link, struct nameidata *nd, void **p) |
1da177e4c Linux-2.6.12-rc2 |
787 |
{ |
7b9337aaf fs: namei fix ->p... |
788 |
struct dentry *dentry = link->dentry; |
6d7b5aaed namei.c: let foll... |
789 790 |
int error; char *s; |
1da177e4c Linux-2.6.12-rc2 |
791 |
|
844a39179 nothing in do_fol... |
792 |
BUG_ON(nd->flags & LOOKUP_RCU); |
0e794589e fix follow_link()... |
793 794 |
if (link->mnt == nd->path.mnt) mntget(link->mnt); |
6d7b5aaed namei.c: let foll... |
795 796 797 |
error = -ELOOP; if (unlikely(current->total_link_count >= 40)) goto out_put_nd_path; |
574197e0d tidy the trailing... |
798 799 |
cond_resched(); current->total_link_count++; |
68ac1234f switch touch_atim... |
800 |
touch_atime(link); |
1da177e4c Linux-2.6.12-rc2 |
801 |
nd_set_link(nd, NULL); |
cd4e91d3b [PATCH] namei fix... |
802 |
|
36f3b4f69 pull security_ino... |
803 |
error = security_inode_follow_link(link->dentry, nd); |
6d7b5aaed namei.c: let foll... |
804 805 |
if (error) goto out_put_nd_path; |
36f3b4f69 pull security_ino... |
806 |
|
86acdca1b fix autofs/afs/et... |
807 |
nd->last_type = LAST_BIND; |
def4af30c Get rid of symlin... |
808 809 |
*p = dentry->d_inode->i_op->follow_link(dentry, nd); error = PTR_ERR(*p); |
6d7b5aaed namei.c: let foll... |
810 |
if (IS_ERR(*p)) |
408ef013c fs: move path_put... |
811 |
goto out_put_nd_path; |
6d7b5aaed namei.c: let foll... |
812 813 814 815 |
error = 0; s = nd_get_link(nd); if (s) { |
443ed254c ... and fold the ... |
816 817 818 819 820 821 822 823 824 825 826 827 828 829 |
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 |
830 831 |
if (unlikely(error)) put_link(nd, link, *p); |
1da177e4c Linux-2.6.12-rc2 |
832 |
} |
6d7b5aaed namei.c: let foll... |
833 834 835 836 |
return error; out_put_nd_path: |
98f6ef64b vfs: bogus warnin... |
837 |
*p = NULL; |
6d7b5aaed namei.c: let foll... |
838 |
path_put(&nd->path); |
6d7b5aaed namei.c: let foll... |
839 |
path_put(link); |
1da177e4c Linux-2.6.12-rc2 |
840 841 |
return error; } |
31e6b01f4 fs: rcu-walk for ... |
842 843 |
static int follow_up_rcu(struct path *path) { |
0714a5338 vfs: now it can b... |
844 845 |
struct mount *mnt = real_mount(path->mnt); struct mount *parent; |
31e6b01f4 fs: rcu-walk for ... |
846 |
struct dentry *mountpoint; |
0714a5338 vfs: now it can b... |
847 848 |
parent = mnt->mnt_parent; if (&parent->mnt == path->mnt) |
31e6b01f4 fs: rcu-walk for ... |
849 |
return 0; |
a73324da7 vfs: move mnt_mou... |
850 |
mountpoint = mnt->mnt_mountpoint; |
31e6b01f4 fs: rcu-walk for ... |
851 |
path->dentry = mountpoint; |
0714a5338 vfs: now it can b... |
852 |
path->mnt = &parent->mnt; |
31e6b01f4 fs: rcu-walk for ... |
853 854 |
return 1; } |
f015f1267 VFS: Comment moun... |
855 856 857 858 859 860 861 862 863 864 |
/* * 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(... |
865 |
int follow_up(struct path *path) |
1da177e4c Linux-2.6.12-rc2 |
866 |
{ |
0714a5338 vfs: now it can b... |
867 868 |
struct mount *mnt = real_mount(path->mnt); struct mount *parent; |
1da177e4c Linux-2.6.12-rc2 |
869 |
struct dentry *mountpoint; |
99b7db7b8 fs: brlock vfsmou... |
870 |
|
48a066e72 RCU'd vfsmounts |
871 |
read_seqlock_excl(&mount_lock); |
0714a5338 vfs: now it can b... |
872 |
parent = mnt->mnt_parent; |
3c0a61636 unobfuscate follo... |
873 |
if (parent == mnt) { |
48a066e72 RCU'd vfsmounts |
874 |
read_sequnlock_excl(&mount_lock); |
1da177e4c Linux-2.6.12-rc2 |
875 876 |
return 0; } |
0714a5338 vfs: now it can b... |
877 |
mntget(&parent->mnt); |
a73324da7 vfs: move mnt_mou... |
878 |
mountpoint = dget(mnt->mnt_mountpoint); |
48a066e72 RCU'd vfsmounts |
879 |
read_sequnlock_excl(&mount_lock); |
bab77ebf5 switch follow_up(... |
880 881 882 |
dput(path->dentry); path->dentry = mountpoint; mntput(path->mnt); |
0714a5338 vfs: now it can b... |
883 |
path->mnt = &parent->mnt; |
1da177e4c Linux-2.6.12-rc2 |
884 885 |
return 1; } |
4d3595073 namei.c: move EXP... |
886 |
EXPORT_SYMBOL(follow_up); |
1da177e4c Linux-2.6.12-rc2 |
887 |
|
b5c84bf6f fs: dcache remove... |
888 |
/* |
9875cf806 Add a dentry op t... |
889 890 891 |
* 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 |
892 |
*/ |
9875cf806 Add a dentry op t... |
893 894 |
static int follow_automount(struct path *path, unsigned flags, bool *need_mntput) |
31e6b01f4 fs: rcu-walk for ... |
895 |
{ |
9875cf806 Add a dentry op t... |
896 |
struct vfsmount *mnt; |
ea5b778a8 Unexport do_add_m... |
897 |
int err; |
9875cf806 Add a dentry op t... |
898 899 900 |
if (!path->dentry->d_op || !path->dentry->d_op->d_automount) return -EREMOTE; |
0ec26fd06 vfs: automount sh... |
901 902 903 904 905 906 907 908 909 910 |
/* 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... |
911 |
*/ |
0ec26fd06 vfs: automount sh... |
912 |
if (!(flags & (LOOKUP_PARENT | LOOKUP_DIRECTORY | |
d94c177be vfs pathname look... |
913 |
LOOKUP_OPEN | LOOKUP_CREATE | LOOKUP_AUTOMOUNT)) && |
0ec26fd06 vfs: automount sh... |
914 915 |
path->dentry->d_inode) return -EISDIR; |
9875cf806 Add a dentry op t... |
916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 |
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 |
931 |
if (PTR_ERR(mnt) == -EISDIR && (flags & LOOKUP_PARENT)) |
9875cf806 Add a dentry op t... |
932 933 |
return -EREMOTE; return PTR_ERR(mnt); |
31e6b01f4 fs: rcu-walk for ... |
934 |
} |
ea5b778a8 Unexport do_add_m... |
935 |
|
9875cf806 Add a dentry op t... |
936 937 |
if (!mnt) /* mount collision */ return 0; |
31e6b01f4 fs: rcu-walk for ... |
938 |
|
8aef18845 VFS: Fix vfsmount... |
939 940 941 942 943 |
if (!*need_mntput) { /* lock_mount() may release path->mnt on error */ mntget(path->mnt); *need_mntput = true; } |
19a167af7 Take the completi... |
944 |
err = finish_automount(mnt, path); |
9875cf806 Add a dentry op t... |
945 |
|
ea5b778a8 Unexport do_add_m... |
946 947 948 |
switch (err) { case -EBUSY: /* Someone else made a mount here whilst we were busy */ |
19a167af7 Take the completi... |
949 |
return 0; |
ea5b778a8 Unexport do_add_m... |
950 |
case 0: |
8aef18845 VFS: Fix vfsmount... |
951 |
path_put(path); |
ea5b778a8 Unexport do_add_m... |
952 953 |
path->mnt = mnt; path->dentry = dget(mnt->mnt_root); |
ea5b778a8 Unexport do_add_m... |
954 |
return 0; |
19a167af7 Take the completi... |
955 956 |
default: return err; |
ea5b778a8 Unexport do_add_m... |
957 |
} |
19a167af7 Take the completi... |
958 |
|
463ffb2e9 [PATCH] namei fix... |
959 |
} |
9875cf806 Add a dentry op t... |
960 961 |
/* * Handle a dentry that is managed in some way. |
cc53ce53c Add a dentry op t... |
962 |
* - Flagged for transit management (autofs) |
9875cf806 Add a dentry op t... |
963 964 965 966 967 968 969 970 |
* - 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 |
971 |
{ |
8aef18845 VFS: Fix vfsmount... |
972 |
struct vfsmount *mnt = path->mnt; /* held by caller, must be left alone */ |
9875cf806 Add a dentry op t... |
973 974 |
unsigned managed; bool need_mntput = false; |
8aef18845 VFS: Fix vfsmount... |
975 |
int ret = 0; |
9875cf806 Add a dentry op t... |
976 977 978 979 980 981 982 |
/* 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... |
983 984 985 986 987 |
/* 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... |
988 |
ret = path->dentry->d_op->d_manage(path->dentry, false); |
cc53ce53c Add a dentry op t... |
989 |
if (ret < 0) |
8aef18845 VFS: Fix vfsmount... |
990 |
break; |
cc53ce53c Add a dentry op t... |
991 |
} |
9875cf806 Add a dentry op t... |
992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 |
/* 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 |
1007 1008 |
* namespace got unmounted before lookup_mnt() could * get it */ |
9875cf806 Add a dentry op t... |
1009 1010 1011 1012 1013 1014 |
} /* Handle an automount point */ if (managed & DCACHE_NEED_AUTOMOUNT) { ret = follow_automount(path, flags, &need_mntput); if (ret < 0) |
8aef18845 VFS: Fix vfsmount... |
1015 |
break; |
9875cf806 Add a dentry op t... |
1016 1017 1018 1019 1020 |
continue; } /* We didn't change the current path point */ break; |
1da177e4c Linux-2.6.12-rc2 |
1021 |
} |
8aef18845 VFS: Fix vfsmount... |
1022 1023 1024 1025 1026 |
if (need_mntput && path->mnt == mnt) mntput(path->mnt); if (ret == -EISDIR) ret = 0; |
a3fbbde70 VFS: we need to s... |
1027 |
return ret < 0 ? ret : need_mntput; |
1da177e4c Linux-2.6.12-rc2 |
1028 |
} |
cc53ce53c Add a dentry op t... |
1029 |
int follow_down_one(struct path *path) |
1da177e4c Linux-2.6.12-rc2 |
1030 1031 |
{ struct vfsmount *mounted; |
1c755af4d switch lookup_mnt() |
1032 |
mounted = lookup_mnt(path); |
1da177e4c Linux-2.6.12-rc2 |
1033 |
if (mounted) { |
9393bd07c switch follow_down() |
1034 1035 1036 1037 |
dput(path->dentry); mntput(path->mnt); path->mnt = mounted; path->dentry = dget(mounted->mnt_root); |
1da177e4c Linux-2.6.12-rc2 |
1038 1039 1040 1041 |
return 1; } return 0; } |
4d3595073 namei.c: move EXP... |
1042 |
EXPORT_SYMBOL(follow_down_one); |
1da177e4c Linux-2.6.12-rc2 |
1043 |
|
62a7375e5 vfs - check non-m... |
1044 1045 1046 1047 1048 |
static inline bool managed_dentry_might_block(struct dentry *dentry) { return (dentry->d_flags & DCACHE_MANAGE_TRANSIT && dentry->d_op->d_manage(dentry, true) < 0); } |
9875cf806 Add a dentry op t... |
1049 |
/* |
287548e46 split __follow_mo... |
1050 1051 |
* 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... |
1052 1053 |
*/ static bool __follow_mount_rcu(struct nameidata *nd, struct path *path, |
287548e46 split __follow_mo... |
1054 |
struct inode **inode) |
9875cf806 Add a dentry op t... |
1055 |
{ |
62a7375e5 vfs - check non-m... |
1056 |
for (;;) { |
c71053659 vfs: spread struc... |
1057 |
struct mount *mounted; |
62a7375e5 vfs - check non-m... |
1058 1059 1060 1061 |
/* * Don't forget we might have a non-mountpoint managed dentry * that wants to block transit. */ |
287548e46 split __follow_mo... |
1062 |
if (unlikely(managed_dentry_might_block(path->dentry))) |
ab90911ff Allow d_manage() ... |
1063 |
return false; |
62a7375e5 vfs - check non-m... |
1064 1065 |
if (!d_mountpoint(path->dentry)) |
b37199e62 rcuwalk: recheck ... |
1066 |
return true; |
62a7375e5 vfs - check non-m... |
1067 |
|
474279dc0 split __lookup_mn... |
1068 |
mounted = __lookup_mnt(path->mnt, path->dentry); |
9875cf806 Add a dentry op t... |
1069 1070 |
if (!mounted) break; |
c71053659 vfs: spread struc... |
1071 1072 |
path->mnt = &mounted->mnt; path->dentry = mounted->mnt.mnt_root; |
a3fbbde70 VFS: we need to s... |
1073 |
nd->flags |= LOOKUP_JUMPED; |
9875cf806 Add a dentry op t... |
1074 |
nd->seq = read_seqcount_begin(&path->dentry->d_seq); |
594302624 vfs: fix race in ... |
1075 1076 1077 1078 1079 1080 |
/* * 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... |
1081 |
} |
b37199e62 rcuwalk: recheck ... |
1082 |
return read_seqretry(&mount_lock, nd->m_seq); |
287548e46 split __follow_mo... |
1083 |
} |
31e6b01f4 fs: rcu-walk for ... |
1084 1085 |
static int follow_dotdot_rcu(struct nameidata *nd) { |
31e6b01f4 fs: rcu-walk for ... |
1086 |
set_root_rcu(nd); |
9875cf806 Add a dentry op t... |
1087 |
while (1) { |
31e6b01f4 fs: rcu-walk for ... |
1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 |
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(... |
1099 |
goto failed; |
31e6b01f4 fs: rcu-walk for ... |
1100 1101 1102 1103 1104 1105 1106 |
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 ... |
1107 |
} |
b37199e62 rcuwalk: recheck ... |
1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 |
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... |
1119 |
nd->inode = nd->path.dentry->d_inode; |
31e6b01f4 fs: rcu-walk for ... |
1120 |
return 0; |
ef7562d52 make handle_dots(... |
1121 1122 1123 |
failed: nd->flags &= ~LOOKUP_RCU; |
5b6ca027d reduce vfs_path_l... |
1124 1125 |
if (!(nd->flags & LOOKUP_ROOT)) nd->root.mnt = NULL; |
8b61e74ff get rid of {lock,... |
1126 |
rcu_read_unlock(); |
ef7562d52 make handle_dots(... |
1127 |
return -ECHILD; |
31e6b01f4 fs: rcu-walk for ... |
1128 |
} |
9875cf806 Add a dentry op t... |
1129 |
/* |
cc53ce53c Add a dentry op t... |
1130 1131 1132 |
* 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... |
1133 |
*/ |
7cc90cc3f don't pass 'mount... |
1134 |
int follow_down(struct path *path) |
cc53ce53c Add a dentry op t... |
1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 |
{ 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() ... |
1154 |
ret = path->dentry->d_op->d_manage( |
1aed3e420 lose 'mounting_he... |
1155 |
path->dentry, false); |
cc53ce53c Add a dentry op t... |
1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 |
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... |
1177 |
EXPORT_SYMBOL(follow_down); |
cc53ce53c Add a dentry op t... |
1178 1179 |
/* |
9875cf806 Add a dentry op t... |
1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 |
* 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 ... |
1194 |
static void follow_dotdot(struct nameidata *nd) |
1da177e4c Linux-2.6.12-rc2 |
1195 |
{ |
2a7378711 Cache root in nam... |
1196 |
set_root(nd); |
e518ddb7b [PATCH] fs/namei.... |
1197 |
|
1da177e4c Linux-2.6.12-rc2 |
1198 |
while(1) { |
4ac913785 Embed a struct pa... |
1199 |
struct dentry *old = nd->path.dentry; |
1da177e4c Linux-2.6.12-rc2 |
1200 |
|
2a7378711 Cache root in nam... |
1201 1202 |
if (nd->path.dentry == nd->root.dentry && nd->path.mnt == nd->root.mnt) { |
1da177e4c Linux-2.6.12-rc2 |
1203 1204 |
break; } |
4ac913785 Embed a struct pa... |
1205 |
if (nd->path.dentry != nd->path.mnt->mnt_root) { |
3088dd708 Clean follow_dotd... |
1206 1207 |
/* rare case of legitimate dget_parent()... */ nd->path.dentry = dget_parent(nd->path.dentry); |
1da177e4c Linux-2.6.12-rc2 |
1208 1209 1210 |
dput(old); break; } |
3088dd708 Clean follow_dotd... |
1211 |
if (!follow_up(&nd->path)) |
1da177e4c Linux-2.6.12-rc2 |
1212 |
break; |
1da177e4c Linux-2.6.12-rc2 |
1213 |
} |
79ed02261 switch follow_mou... |
1214 |
follow_mount(&nd->path); |
31e6b01f4 fs: rcu-walk for ... |
1215 |
nd->inode = nd->path.dentry->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
1216 |
} |
1da177e4c Linux-2.6.12-rc2 |
1217 |
/* |
bad611897 vfs: split __look... |
1218 1219 1220 1221 1222 |
* 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... |
1223 |
*/ |
bad611897 vfs: split __look... |
1224 |
static struct dentry *lookup_dcache(struct qstr *name, struct dentry *dir, |
201f956e4 fs/namei.c: don't... |
1225 |
unsigned int flags, bool *need_lookup) |
baa038907 fs: dentry alloca... |
1226 |
{ |
baa038907 fs: dentry alloca... |
1227 |
struct dentry *dentry; |
bad611897 vfs: split __look... |
1228 |
int error; |
baa038907 fs: dentry alloca... |
1229 |
|
bad611897 vfs: split __look... |
1230 1231 1232 |
*need_lookup = false; dentry = d_lookup(dir, name); if (dentry) { |
39e3c9553 vfs: remove DCACH... |
1233 |
if (dentry->d_flags & DCACHE_OP_REVALIDATE) { |
201f956e4 fs/namei.c: don't... |
1234 |
error = d_revalidate(dentry, flags); |
bad611897 vfs: split __look... |
1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 |
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... |
1246 |
|
bad611897 vfs: split __look... |
1247 1248 1249 1250 |
if (!dentry) { dentry = d_alloc(dir, name); if (unlikely(!dentry)) return ERR_PTR(-ENOMEM); |
baa038907 fs: dentry alloca... |
1251 |
|
bad611897 vfs: split __look... |
1252 |
*need_lookup = true; |
baa038907 fs: dentry alloca... |
1253 1254 1255 1256 1257 |
} return dentry; } /* |
13a2c3be0 dcache: fix outda... |
1258 1259 |
* Call i_op->lookup on the dentry. The dentry must be negative and * unhashed. |
bad611897 vfs: split __look... |
1260 1261 |
* * dir->d_inode->i_mutex must be held |
44396f4b5 fs: add a DCACHE_... |
1262 |
*/ |
bad611897 vfs: split __look... |
1263 |
static struct dentry *lookup_real(struct inode *dir, struct dentry *dentry, |
72bd866a0 fs/namei.c: don't... |
1264 |
unsigned int flags) |
44396f4b5 fs: add a DCACHE_... |
1265 |
{ |
44396f4b5 fs: add a DCACHE_... |
1266 1267 1268 |
struct dentry *old; /* Don't create child dentry for a dead directory. */ |
bad611897 vfs: split __look... |
1269 |
if (unlikely(IS_DEADDIR(dir))) { |
e188dc02d vfs: fix d_inode_... |
1270 |
dput(dentry); |
44396f4b5 fs: add a DCACHE_... |
1271 |
return ERR_PTR(-ENOENT); |
e188dc02d vfs: fix d_inode_... |
1272 |
} |
44396f4b5 fs: add a DCACHE_... |
1273 |
|
72bd866a0 fs/namei.c: don't... |
1274 |
old = dir->i_op->lookup(dir, dentry, flags); |
44396f4b5 fs: add a DCACHE_... |
1275 1276 1277 1278 1279 1280 |
if (unlikely(old)) { dput(dentry); dentry = old; } return dentry; } |
a32555466 untangling do_loo... |
1281 |
static struct dentry *__lookup_hash(struct qstr *name, |
72bd866a0 fs/namei.c: don't... |
1282 |
struct dentry *base, unsigned int flags) |
a32555466 untangling do_loo... |
1283 |
{ |
bad611897 vfs: split __look... |
1284 |
bool need_lookup; |
a32555466 untangling do_loo... |
1285 |
struct dentry *dentry; |
72bd866a0 fs/namei.c: don't... |
1286 |
dentry = lookup_dcache(name, base, flags, &need_lookup); |
bad611897 vfs: split __look... |
1287 1288 |
if (!need_lookup) return dentry; |
a32555466 untangling do_loo... |
1289 |
|
72bd866a0 fs/namei.c: don't... |
1290 |
return lookup_real(base->d_inode, dentry, flags); |
a32555466 untangling do_loo... |
1291 |
} |
44396f4b5 fs: add a DCACHE_... |
1292 |
/* |
1da177e4c Linux-2.6.12-rc2 |
1293 1294 1295 1296 |
* 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 ... |
1297 |
static int lookup_fast(struct nameidata *nd, |
697f514df vfs: split do_loo... |
1298 |
struct path *path, struct inode **inode) |
1da177e4c Linux-2.6.12-rc2 |
1299 |
{ |
4ac913785 Embed a struct pa... |
1300 |
struct vfsmount *mnt = nd->path.mnt; |
31e6b01f4 fs: rcu-walk for ... |
1301 |
struct dentry *dentry, *parent = nd->path.dentry; |
5a18fff20 untangle do_lookup() |
1302 1303 |
int need_reval = 1; int status = 1; |
9875cf806 Add a dentry op t... |
1304 |
int err; |
3cac260ad Take hash recalcu... |
1305 |
/* |
b04f784e5 fs: remove extra ... |
1306 1307 1308 1309 |
* 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 ... |
1310 1311 |
if (nd->flags & LOOKUP_RCU) { unsigned seq; |
da53be12b Don't pass inode ... |
1312 |
dentry = __d_lookup_rcu(parent, &nd->last, &seq); |
5a18fff20 untangle do_lookup() |
1313 1314 |
if (!dentry) goto unlazy; |
12f8ad4b0 vfs: clean up __d... |
1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 |
/* * 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 ... |
1330 1331 |
if (__read_seqcount_retry(&parent->d_seq, nd->seq)) return -ECHILD; |
31e6b01f4 fs: rcu-walk for ... |
1332 |
nd->seq = seq; |
5a18fff20 untangle do_lookup() |
1333 |
|
24643087e in do_lookup() sp... |
1334 |
if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE)) { |
4ce16ef3f fs/namei.c: don't... |
1335 |
status = d_revalidate(dentry, nd->flags); |
5a18fff20 untangle do_lookup() |
1336 1337 1338 1339 1340 |
if (unlikely(status <= 0)) { if (status != -ECHILD) need_reval = 0; goto unlazy; } |
24643087e in do_lookup() sp... |
1341 |
} |
31e6b01f4 fs: rcu-walk for ... |
1342 1343 |
path->mnt = mnt; path->dentry = dentry; |
d6e9bd256 Lift the check fo... |
1344 1345 1346 1347 1348 |
if (unlikely(!__follow_mount_rcu(nd, path, inode))) goto unlazy; if (unlikely(path->dentry->d_flags & DCACHE_NEED_AUTOMOUNT)) goto unlazy; return 0; |
5a18fff20 untangle do_lookup() |
1349 |
unlazy: |
19660af73 consolidate namei... |
1350 1351 |
if (unlazy_walk(nd, dentry)) return -ECHILD; |
5a18fff20 untangle do_lookup() |
1352 |
} else { |
e97cdc87b lookup_fast: get ... |
1353 |
dentry = __d_lookup(parent, &nd->last); |
9875cf806 Add a dentry op t... |
1354 |
} |
5a18fff20 untangle do_lookup() |
1355 |
|
81e6f5208 untangling do_loo... |
1356 1357 |
if (unlikely(!dentry)) goto need_lookup; |
5a18fff20 untangle do_lookup() |
1358 |
if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE) && need_reval) |
4ce16ef3f fs/namei.c: don't... |
1359 |
status = d_revalidate(dentry, nd->flags); |
5a18fff20 untangle do_lookup() |
1360 1361 1362 1363 1364 1365 1366 |
if (unlikely(status <= 0)) { if (status < 0) { dput(dentry); return status; } if (!d_invalidate(dentry)) { dput(dentry); |
81e6f5208 untangling do_loo... |
1367 |
goto need_lookup; |
5a18fff20 untangle do_lookup() |
1368 |
} |
24643087e in do_lookup() sp... |
1369 |
} |
697f514df vfs: split do_loo... |
1370 |
|
9875cf806 Add a dentry op t... |
1371 1372 1373 |
path->mnt = mnt; path->dentry = dentry; err = follow_managed(path, nd->flags); |
893122141 vfs - fix dentry ... |
1374 1375 |
if (unlikely(err < 0)) { path_put_conditional(path, nd); |
9875cf806 Add a dentry op t... |
1376 |
return err; |
893122141 vfs - fix dentry ... |
1377 |
} |
a3fbbde70 VFS: we need to s... |
1378 1379 |
if (err) nd->flags |= LOOKUP_JUMPED; |
9875cf806 Add a dentry op t... |
1380 |
*inode = path->dentry->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
1381 |
return 0; |
81e6f5208 untangling do_loo... |
1382 1383 |
need_lookup: |
697f514df vfs: split do_loo... |
1384 1385 1386 1387 |
return 1; } /* Fast lookup failed, do it the slow way */ |
cc2a52711 lookup_slow: get ... |
1388 |
static int lookup_slow(struct nameidata *nd, struct path *path) |
697f514df vfs: split do_loo... |
1389 1390 1391 1392 1393 |
{ struct dentry *dentry, *parent; int err; parent = nd->path.dentry; |
81e6f5208 untangling do_loo... |
1394 1395 1396 |
BUG_ON(nd->inode != parent->d_inode); mutex_lock(&parent->d_inode->i_mutex); |
cc2a52711 lookup_slow: get ... |
1397 |
dentry = __lookup_hash(&nd->last, parent, nd->flags); |
81e6f5208 untangling do_loo... |
1398 1399 1400 |
mutex_unlock(&parent->d_inode->i_mutex); if (IS_ERR(dentry)) return PTR_ERR(dentry); |
697f514df vfs: split do_loo... |
1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 |
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 |
1411 |
} |
52094c8a0 take RCU-dependen... |
1412 1413 1414 |
static inline int may_lookup(struct nameidata *nd) { if (nd->flags & LOOKUP_RCU) { |
4ad5abb3d no reason to keep... |
1415 |
int err = inode_permission(nd->inode, MAY_EXEC|MAY_NOT_BLOCK); |
52094c8a0 take RCU-dependen... |
1416 1417 |
if (err != -ECHILD) return err; |
19660af73 consolidate namei... |
1418 |
if (unlazy_walk(nd, NULL)) |
52094c8a0 take RCU-dependen... |
1419 1420 |
return -ECHILD; } |
4ad5abb3d no reason to keep... |
1421 |
return inode_permission(nd->inode, MAY_EXEC); |
52094c8a0 take RCU-dependen... |
1422 |
} |
9856fa1b2 pull handling of ... |
1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 |
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... |
1434 1435 1436 1437 1438 1439 |
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... |
1440 1441 |
if (!(nd->flags & LOOKUP_ROOT)) nd->root.mnt = NULL; |
8b61e74ff get rid of {lock,... |
1442 |
rcu_read_unlock(); |
951361f95 get rid of the la... |
1443 1444 |
} } |
3ddcd0569 vfs: optimize ino... |
1445 1446 1447 1448 1449 1450 |
/* * 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 ... |
1451 |
static inline int should_follow_link(struct dentry *dentry, int follow) |
3ddcd0569 vfs: optimize ino... |
1452 |
{ |
b18825a7c VFS: Put a small ... |
1453 |
return unlikely(d_is_symlink(dentry)) ? follow : 0; |
3ddcd0569 vfs: optimize ino... |
1454 |
} |
ce57dfc17 pull handling of ... |
1455 |
static inline int walk_component(struct nameidata *nd, struct path *path, |
21b9b0739 get rid of name a... |
1456 |
int follow) |
ce57dfc17 pull handling of ... |
1457 1458 1459 1460 1461 1462 1463 1464 |
{ 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... |
1465 1466 |
if (unlikely(nd->last_type != LAST_NORM)) return handle_dots(nd, nd->last_type); |
e97cdc87b lookup_fast: get ... |
1467 |
err = lookup_fast(nd, path, &inode); |
ce57dfc17 pull handling of ... |
1468 |
if (unlikely(err)) { |
697f514df vfs: split do_loo... |
1469 1470 |
if (err < 0) goto out_err; |
cc2a52711 lookup_slow: get ... |
1471 |
err = lookup_slow(nd, path); |
697f514df vfs: split do_loo... |
1472 1473 1474 1475 |
if (err < 0) goto out_err; inode = path->dentry->d_inode; |
ce57dfc17 pull handling of ... |
1476 |
} |
697f514df vfs: split do_loo... |
1477 1478 1479 |
err = -ENOENT; if (!inode) goto out_path_put; |
b18825a7c VFS: Put a small ... |
1480 |
if (should_follow_link(path->dentry, follow)) { |
19660af73 consolidate namei... |
1481 1482 |
if (nd->flags & LOOKUP_RCU) { if (unlikely(unlazy_walk(nd, path->dentry))) { |
697f514df vfs: split do_loo... |
1483 1484 |
err = -ECHILD; goto out_err; |
19660af73 consolidate namei... |
1485 1486 |
} } |
ce57dfc17 pull handling of ... |
1487 1488 1489 1490 1491 1492 |
BUG_ON(inode != path->dentry->d_inode); return 1; } path_to_nameidata(path, nd); nd->inode = inode; return 0; |
697f514df vfs: split do_loo... |
1493 1494 1495 1496 1497 1498 |
out_path_put: path_to_nameidata(path, nd); out_err: terminate_walk(nd); return err; |
ce57dfc17 pull handling of ... |
1499 |
} |
1da177e4c Linux-2.6.12-rc2 |
1500 |
/* |
b356379a0 Turn resolution o... |
1501 1502 1503 1504 1505 1506 1507 1508 1509 |
* 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... |
1510 1511 1512 1513 1514 |
if (unlikely(current->link_count >= MAX_NESTED_LINKS)) { path_put_conditional(path, nd); path_put(&nd->path); return -ELOOP; } |
1a4022f88 VFS: move BUG_ON ... |
1515 |
BUG_ON(nd->depth >= MAX_NESTED_LINKS); |
b356379a0 Turn resolution o... |
1516 1517 1518 1519 1520 1521 1522 |
nd->depth++; current->link_count++; do { struct path link = *path; void *cookie; |
574197e0d tidy the trailing... |
1523 1524 |
res = follow_link(&link, nd, &cookie); |
6d7b5aaed namei.c: let foll... |
1525 1526 |
if (res) break; |
21b9b0739 get rid of name a... |
1527 |
res = walk_component(nd, path, LOOKUP_FOLLOW); |
574197e0d tidy the trailing... |
1528 |
put_link(nd, &link, cookie); |
b356379a0 Turn resolution o... |
1529 1530 1531 1532 1533 1534 1535 1536 |
} while (res > 0); current->link_count--; nd->depth--; return res; } /* |
bfcfaa77b vfs: use 'unsigne... |
1537 1538 1539 1540 1541 1542 1543 |
* 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... |
1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 |
* - 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... |
1554 |
#include <asm/word-at-a-time.h> |
bfcfaa77b vfs: use 'unsigne... |
1555 |
|
f68e556e2 Make the "word-at... |
1556 |
#ifdef CONFIG_64BIT |
bfcfaa77b vfs: use 'unsigne... |
1557 1558 1559 1560 1561 1562 1563 1564 |
static inline unsigned int fold_hash(unsigned long hash) { hash += hash >> (8*sizeof(int)); return hash; } #else /* 32-bit case */ |
bfcfaa77b vfs: use 'unsigne... |
1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 |
#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... |
1575 |
a = load_unaligned_zeropad(name); |
bfcfaa77b vfs: use 'unsigne... |
1576 1577 1578 |
if (len < sizeof(unsigned long)) break; hash += a; |
f132c5be0 Fix full_name_has... |
1579 |
hash *= 9; |
bfcfaa77b vfs: use 'unsigne... |
1580 1581 1582 1583 1584 |
name += sizeof(unsigned long); len -= sizeof(unsigned long); if (!len) goto done; } |
a5c21dcef dcache: allow wor... |
1585 |
mask = bytemask_from_count(len); |
bfcfaa77b vfs: use 'unsigne... |
1586 1587 1588 1589 1590 |
hash += mask & a; done: return fold_hash(hash); } EXPORT_SYMBOL(full_name_hash); |
bfcfaa77b vfs: use 'unsigne... |
1591 1592 1593 1594 1595 1596 |
/* * 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... |
1597 1598 |
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... |
1599 1600 1601 1602 1603 1604 |
hash = a = 0; len = -sizeof(unsigned long); do { hash = (hash + a) * 9; len += sizeof(unsigned long); |
e419b4cc5 vfs: make word-at... |
1605 |
a = load_unaligned_zeropad(name+len); |
36126f8f2 word-at-a-time: m... |
1606 1607 1608 1609 1610 1611 1612 1613 1614 |
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... |
1615 |
*hashp = fold_hash(hash); |
36126f8f2 word-at-a-time: m... |
1616 |
return len + find_zero(mask); |
bfcfaa77b vfs: use 'unsigne... |
1617 1618 1619 |
} #else |
0145acc20 vfs: uninline ful... |
1620 1621 1622 1623 1624 1625 1626 |
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_... |
1627 |
EXPORT_SYMBOL(full_name_hash); |
0145acc20 vfs: uninline ful... |
1628 |
|
3ddcd0569 vfs: optimize ino... |
1629 |
/* |
200e9ef7a vfs: split up nam... |
1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 |
* 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... |
1647 |
#endif |
200e9ef7a vfs: split up nam... |
1648 |
/* |
1da177e4c Linux-2.6.12-rc2 |
1649 |
* Name resolution. |
ea3834d9f namei: add audit_... |
1650 1651 |
* 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 |
1652 |
* |
ea3834d9f namei: add audit_... |
1653 1654 |
* 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 |
1655 |
*/ |
6de88d729 kill __link_path_... |
1656 |
static int link_path_walk(const char *name, struct nameidata *nd) |
1da177e4c Linux-2.6.12-rc2 |
1657 1658 |
{ struct path next; |
1da177e4c Linux-2.6.12-rc2 |
1659 |
int err; |
1da177e4c Linux-2.6.12-rc2 |
1660 1661 1662 1663 |
while (*name=='/') name++; if (!*name) |
086e183a6 pull dropping RCU... |
1664 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
1665 |
|
1da177e4c Linux-2.6.12-rc2 |
1666 1667 |
/* At this point we know we have a real path component. */ for(;;) { |
1da177e4c Linux-2.6.12-rc2 |
1668 |
struct qstr this; |
200e9ef7a vfs: split up nam... |
1669 |
long len; |
fe479a580 merge component t... |
1670 |
int type; |
1da177e4c Linux-2.6.12-rc2 |
1671 |
|
52094c8a0 take RCU-dependen... |
1672 |
err = may_lookup(nd); |
1da177e4c Linux-2.6.12-rc2 |
1673 1674 |
if (err) break; |
200e9ef7a vfs: split up nam... |
1675 |
len = hash_name(name, &this.hash); |
1da177e4c Linux-2.6.12-rc2 |
1676 |
this.name = name; |
200e9ef7a vfs: split up nam... |
1677 |
this.len = len; |
1da177e4c Linux-2.6.12-rc2 |
1678 |
|
fe479a580 merge component t... |
1679 |
type = LAST_NORM; |
200e9ef7a vfs: split up nam... |
1680 |
if (name[0] == '.') switch (len) { |
fe479a580 merge component t... |
1681 |
case 2: |
200e9ef7a vfs: split up nam... |
1682 |
if (name[1] == '.') { |
fe479a580 merge component t... |
1683 |
type = LAST_DOTDOT; |
16c2cd717 untangle the "nee... |
1684 1685 |
nd->flags |= LOOKUP_JUMPED; } |
fe479a580 merge component t... |
1686 1687 1688 1689 |
break; case 1: type = LAST_DOT; } |
5a202bcd7 sanitize pathname... |
1690 1691 |
if (likely(type == LAST_NORM)) { struct dentry *parent = nd->path.dentry; |
16c2cd717 untangle the "nee... |
1692 |
nd->flags &= ~LOOKUP_JUMPED; |
5a202bcd7 sanitize pathname... |
1693 |
if (unlikely(parent->d_flags & DCACHE_OP_HASH)) { |
da53be12b Don't pass inode ... |
1694 |
err = parent->d_op->d_hash(parent, &this); |
5a202bcd7 sanitize pathname... |
1695 1696 1697 1698 |
if (err < 0) break; } } |
fe479a580 merge component t... |
1699 |
|
5f4a6a695 link_path_walk():... |
1700 1701 |
nd->last = this; nd->last_type = type; |
200e9ef7a vfs: split up nam... |
1702 |
if (!name[len]) |
5f4a6a695 link_path_walk():... |
1703 |
return 0; |
200e9ef7a vfs: split up nam... |
1704 1705 1706 1707 1708 1709 1710 1711 |
/* * 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():... |
1712 |
return 0; |
200e9ef7a vfs: split up nam... |
1713 |
name += len; |
1da177e4c Linux-2.6.12-rc2 |
1714 |
|
21b9b0739 get rid of name a... |
1715 |
err = walk_component(nd, &next, LOOKUP_FOLLOW); |
ce57dfc17 pull handling of ... |
1716 1717 |
if (err < 0) return err; |
1da177e4c Linux-2.6.12-rc2 |
1718 |
|
ce57dfc17 pull handling of ... |
1719 |
if (err) { |
b356379a0 Turn resolution o... |
1720 |
err = nested_symlink(&next, nd); |
1da177e4c Linux-2.6.12-rc2 |
1721 |
if (err) |
a7472baba make nameidata_de... |
1722 |
return err; |
31e6b01f4 fs: rcu-walk for ... |
1723 |
} |
44b1d5304 vfs: add d_is_dir() |
1724 |
if (!d_can_lookup(nd->path.dentry)) { |
5f4a6a695 link_path_walk():... |
1725 1726 1727 |
err = -ENOTDIR; break; } |
1da177e4c Linux-2.6.12-rc2 |
1728 |
} |
951361f95 get rid of the la... |
1729 |
terminate_walk(nd); |
1da177e4c Linux-2.6.12-rc2 |
1730 1731 |
return err; } |
70e9b3571 get rid of nd->file |
1732 1733 |
static int path_init(int dfd, const char *name, unsigned int flags, struct nameidata *nd, struct file **fp) |
31e6b01f4 fs: rcu-walk for ... |
1734 1735 |
{ int retval = 0; |
31e6b01f4 fs: rcu-walk for ... |
1736 1737 |
nd->last_type = LAST_ROOT; /* if there are only slashes... */ |
16c2cd717 untangle the "nee... |
1738 |
nd->flags = flags | LOOKUP_JUMPED; |
31e6b01f4 fs: rcu-walk for ... |
1739 |
nd->depth = 0; |
5b6ca027d reduce vfs_path_l... |
1740 |
if (flags & LOOKUP_ROOT) { |
b18825a7c VFS: Put a small ... |
1741 1742 |
struct dentry *root = nd->root.dentry; struct inode *inode = root->d_inode; |
73d049a40 open-style analog... |
1743 |
if (*name) { |
44b1d5304 vfs: add d_is_dir() |
1744 |
if (!d_can_lookup(root)) |
73d049a40 open-style analog... |
1745 1746 1747 1748 1749 |
return -ENOTDIR; retval = inode_permission(inode, MAY_EXEC); if (retval) return retval; } |
5b6ca027d reduce vfs_path_l... |
1750 1751 1752 |
nd->path = nd->root; nd->inode = inode; if (flags & LOOKUP_RCU) { |
8b61e74ff get rid of {lock,... |
1753 |
rcu_read_lock(); |
5b6ca027d reduce vfs_path_l... |
1754 |
nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq); |
48a066e72 RCU'd vfsmounts |
1755 |
nd->m_seq = read_seqbegin(&mount_lock); |
5b6ca027d reduce vfs_path_l... |
1756 1757 1758 1759 1760 |
} else { path_get(&nd->path); } return 0; } |
31e6b01f4 fs: rcu-walk for ... |
1761 |
nd->root.mnt = NULL; |
31e6b01f4 fs: rcu-walk for ... |
1762 |
|
48a066e72 RCU'd vfsmounts |
1763 |
nd->m_seq = read_seqbegin(&mount_lock); |
31e6b01f4 fs: rcu-walk for ... |
1764 |
if (*name=='/') { |
e41f7d4ee merge path_init a... |
1765 |
if (flags & LOOKUP_RCU) { |
8b61e74ff get rid of {lock,... |
1766 |
rcu_read_lock(); |
e41f7d4ee merge path_init a... |
1767 1768 1769 1770 1771 1772 |
set_root_rcu(nd); } else { set_root(nd); path_get(&nd->root); } nd->path = nd->root; |
31e6b01f4 fs: rcu-walk for ... |
1773 |
} else if (dfd == AT_FDCWD) { |
e41f7d4ee merge path_init a... |
1774 1775 1776 |
if (flags & LOOKUP_RCU) { struct fs_struct *fs = current->fs; unsigned seq; |
31e6b01f4 fs: rcu-walk for ... |
1777 |
|
8b61e74ff get rid of {lock,... |
1778 |
rcu_read_lock(); |
c28cc3646 fs: fs_struct use... |
1779 |
|
e41f7d4ee merge path_init a... |
1780 1781 1782 1783 1784 1785 1786 1787 |
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 ... |
1788 |
} else { |
582aa64a0 vfs: remove unnee... |
1789 |
/* Caller must check execute permissions on the starting path component */ |
2903ff019 switch simple cas... |
1790 |
struct fd f = fdget_raw(dfd); |
31e6b01f4 fs: rcu-walk for ... |
1791 |
struct dentry *dentry; |
2903ff019 switch simple cas... |
1792 1793 |
if (!f.file) return -EBADF; |
31e6b01f4 fs: rcu-walk for ... |
1794 |
|
2903ff019 switch simple cas... |
1795 |
dentry = f.file->f_path.dentry; |
31e6b01f4 fs: rcu-walk for ... |
1796 |
|
f52e0c113 New AT_... flag: ... |
1797 |
if (*name) { |
44b1d5304 vfs: add d_is_dir() |
1798 |
if (!d_can_lookup(dentry)) { |
2903ff019 switch simple cas... |
1799 1800 1801 |
fdput(f); return -ENOTDIR; } |
f52e0c113 New AT_... flag: ... |
1802 |
} |
31e6b01f4 fs: rcu-walk for ... |
1803 |
|
2903ff019 switch simple cas... |
1804 |
nd->path = f.file->f_path; |
e41f7d4ee merge path_init a... |
1805 |
if (flags & LOOKUP_RCU) { |
9c225f265 vfs: atomic f_pos... |
1806 |
if (f.flags & FDPUT_FPUT) |
2903ff019 switch simple cas... |
1807 |
*fp = f.file; |
e41f7d4ee merge path_init a... |
1808 |
nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq); |
8b61e74ff get rid of {lock,... |
1809 |
rcu_read_lock(); |
e41f7d4ee merge path_init a... |
1810 |
} else { |
2903ff019 switch simple cas... |
1811 1812 |
path_get(&nd->path); fdput(f); |
e41f7d4ee merge path_init a... |
1813 |
} |
31e6b01f4 fs: rcu-walk for ... |
1814 |
} |
31e6b01f4 fs: rcu-walk for ... |
1815 |
|
31e6b01f4 fs: rcu-walk for ... |
1816 |
nd->inode = nd->path.dentry->d_inode; |
9b4a9b14a Preparations to c... |
1817 |
return 0; |
9b4a9b14a Preparations to c... |
1818 |
} |
bd92d7fed Make trailing sym... |
1819 1820 1821 1822 1823 1824 |
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... |
1825 |
return walk_component(nd, path, nd->flags & LOOKUP_FOLLOW); |
bd92d7fed Make trailing sym... |
1826 |
} |
9b4a9b14a Preparations to c... |
1827 |
/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */ |
ee0827cd6 sanitize path_wal... |
1828 |
static int path_lookupat(int dfd, const char *name, |
9b4a9b14a Preparations to c... |
1829 1830 |
unsigned int flags, struct nameidata *nd) { |
70e9b3571 get rid of nd->file |
1831 |
struct file *base = NULL; |
bd92d7fed Make trailing sym... |
1832 1833 |
struct path path; int err; |
31e6b01f4 fs: rcu-walk for ... |
1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 |
/* * 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... |
1849 |
err = path_init(dfd, name, flags | LOOKUP_PARENT, nd, &base); |
ee0827cd6 sanitize path_wal... |
1850 |
|
bd92d7fed Make trailing sym... |
1851 1852 |
if (unlikely(err)) return err; |
ee0827cd6 sanitize path_wal... |
1853 1854 |
current->total_link_count = 0; |
bd92d7fed Make trailing sym... |
1855 1856 1857 |
err = link_path_walk(name, nd); if (!err && !(flags & LOOKUP_PARENT)) { |
bd92d7fed Make trailing sym... |
1858 1859 1860 1861 |
err = lookup_last(nd, &path); while (err > 0) { void *cookie; struct path link = path; |
800179c9b fs: add link rest... |
1862 1863 1864 |
err = may_follow_link(&link, nd); if (unlikely(err)) break; |
bd92d7fed Make trailing sym... |
1865 |
nd->flags |= LOOKUP_PARENT; |
574197e0d tidy the trailing... |
1866 |
err = follow_link(&link, nd, &cookie); |
6d7b5aaed namei.c: let foll... |
1867 1868 1869 |
if (err) break; err = lookup_last(nd, &path); |
574197e0d tidy the trailing... |
1870 |
put_link(nd, &link, cookie); |
bd92d7fed Make trailing sym... |
1871 1872 |
} } |
ee0827cd6 sanitize path_wal... |
1873 |
|
9f1fafee9 merge handle_reva... |
1874 1875 |
if (!err) err = complete_walk(nd); |
bd92d7fed Make trailing sym... |
1876 1877 |
if (!err && nd->flags & LOOKUP_DIRECTORY) { |
44b1d5304 vfs: add d_is_dir() |
1878 |
if (!d_can_lookup(nd->path.dentry)) { |
bd92d7fed Make trailing sym... |
1879 |
path_put(&nd->path); |
bd23a539d fix leaks in path... |
1880 |
err = -ENOTDIR; |
bd92d7fed Make trailing sym... |
1881 1882 |
} } |
16c2cd717 untangle the "nee... |
1883 |
|
70e9b3571 get rid of nd->file |
1884 1885 |
if (base) fput(base); |
ee0827cd6 sanitize path_wal... |
1886 |
|
5b6ca027d reduce vfs_path_l... |
1887 |
if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) { |
2a7378711 Cache root in nam... |
1888 1889 1890 |
path_put(&nd->root); nd->root.mnt = NULL; } |
bd92d7fed Make trailing sym... |
1891 |
return err; |
ee0827cd6 sanitize path_wal... |
1892 |
} |
31e6b01f4 fs: rcu-walk for ... |
1893 |
|
873f1eedc vfs: turn do_path... |
1894 |
static int filename_lookup(int dfd, struct filename *name, |
ee0827cd6 sanitize path_wal... |
1895 1896 |
unsigned int flags, struct nameidata *nd) { |
873f1eedc vfs: turn do_path... |
1897 |
int retval = path_lookupat(dfd, name->name, flags | LOOKUP_RCU, nd); |
ee0827cd6 sanitize path_wal... |
1898 |
if (unlikely(retval == -ECHILD)) |
873f1eedc vfs: turn do_path... |
1899 |
retval = path_lookupat(dfd, name->name, flags, nd); |
ee0827cd6 sanitize path_wal... |
1900 |
if (unlikely(retval == -ESTALE)) |
873f1eedc vfs: turn do_path... |
1901 1902 |
retval = path_lookupat(dfd, name->name, flags | LOOKUP_REVAL, nd); |
31e6b01f4 fs: rcu-walk for ... |
1903 |
|
f78570dd6 audit: remove unn... |
1904 |
if (likely(!retval)) |
adb5c2473 audit: make audit... |
1905 |
audit_inode(name, nd->path.dentry, flags & LOOKUP_PARENT); |
170aa3d02 [PATCH] namei.c: ... |
1906 |
return retval; |
1da177e4c Linux-2.6.12-rc2 |
1907 |
} |
873f1eedc vfs: turn do_path... |
1908 1909 1910 1911 1912 1913 1914 |
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... |
1915 1916 |
/* does lookup, returns the object with parent locked */ struct dentry *kern_path_locked(const char *name, struct path *path) |
5590ff0d5 [PATCH] vfs: *at ... |
1917 |
{ |
79714f72d get rid of kern_p... |
1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 |
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... |
1928 |
d = __lookup_hash(&nd.last, nd.path.dentry, 0); |
79714f72d get rid of kern_p... |
1929 1930 1931 1932 1933 1934 1935 |
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 ... |
1936 |
} |
d18114657 [PATCH] new helpe... |
1937 1938 1939 1940 1941 1942 1943 1944 |
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... |
1945 |
EXPORT_SYMBOL(kern_path); |
d18114657 [PATCH] new helpe... |
1946 |
|
16f182002 fs: introduce vfs... |
1947 1948 1949 1950 1951 1952 |
/** * 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... |
1953 |
* @path: pointer to struct path to fill |
16f182002 fs: introduce vfs... |
1954 1955 1956 |
*/ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt, const char *name, unsigned int flags, |
e0a012493 switch vfs_path_l... |
1957 |
struct path *path) |
16f182002 fs: introduce vfs... |
1958 |
{ |
e0a012493 switch vfs_path_l... |
1959 1960 1961 1962 1963 |
struct nameidata nd; int err; nd.root.dentry = dentry; nd.root.mnt = mnt; BUG_ON(flags & LOOKUP_PARENT); |
5b6ca027d reduce vfs_path_l... |
1964 |
/* the first argument of do_path_lookup() is ignored with LOOKUP_ROOT */ |
e0a012493 switch vfs_path_l... |
1965 1966 1967 1968 |
err = do_path_lookup(AT_FDCWD, name, flags | LOOKUP_ROOT, &nd); if (!err) *path = nd.path; return err; |
16f182002 fs: introduce vfs... |
1969 |
} |
4d3595073 namei.c: move EXP... |
1970 |
EXPORT_SYMBOL(vfs_path_lookup); |
16f182002 fs: introduce vfs... |
1971 |
|
057f6c019 security: prevent... |
1972 1973 1974 1975 1976 |
/* * 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 ... |
1977 |
static struct dentry *lookup_hash(struct nameidata *nd) |
057f6c019 security: prevent... |
1978 |
{ |
72bd866a0 fs/namei.c: don't... |
1979 |
return __lookup_hash(&nd->last, nd->path.dentry, nd->flags); |
1da177e4c Linux-2.6.12-rc2 |
1980 |
} |
eead19115 partially fix up ... |
1981 |
/** |
a6b91919e fs: fix kernel-do... |
1982 |
* lookup_one_len - filesystem helper to lookup single pathname component |
eead19115 partially fix up ... |
1983 1984 1985 1986 |
* @name: pathname component to lookup * @base: base directory to lookup from * @len: maximum length @len should be interpreted to * |
a6b91919e fs: fix kernel-do... |
1987 1988 |
* 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 ... |
1989 1990 1991 |
* nameidata argument is passed to the filesystem methods and a filesystem * using this helper needs to be prepared for that. */ |
057f6c019 security: prevent... |
1992 1993 |
struct dentry *lookup_one_len(const char *name, struct dentry *base, int len) { |
057f6c019 security: prevent... |
1994 |
struct qstr this; |
6a96ba544 kill __lookup_one... |
1995 |
unsigned int c; |
cda309de2 vfs: move MAY_EXE... |
1996 |
int err; |
057f6c019 security: prevent... |
1997 |
|
2f9092e10 Fix i_mutex vs. r... |
1998 |
WARN_ON_ONCE(!mutex_is_locked(&base->d_inode->i_mutex)); |
6a96ba544 kill __lookup_one... |
1999 2000 |
this.name = name; this.len = len; |
0145acc20 vfs: uninline ful... |
2001 |
this.hash = full_name_hash(name, len); |
6a96ba544 kill __lookup_one... |
2002 2003 |
if (!len) return ERR_PTR(-EACCES); |
21d8a15ac lookup_one_len: d... |
2004 2005 2006 2007 |
if (unlikely(name[0] == '.')) { if (len < 2 || (len == 2 && name[1] == '.')) return ERR_PTR(-EACCES); } |
6a96ba544 kill __lookup_one... |
2008 2009 2010 2011 |
while (len--) { c = *(const unsigned char *)name++; if (c == '/' || c == '\0') return ERR_PTR(-EACCES); |
6a96ba544 kill __lookup_one... |
2012 |
} |
5a202bcd7 sanitize pathname... |
2013 2014 2015 2016 2017 |
/* * 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 ... |
2018 |
int err = base->d_op->d_hash(base, &this); |
5a202bcd7 sanitize pathname... |
2019 2020 2021 |
if (err < 0) return ERR_PTR(err); } |
eead19115 partially fix up ... |
2022 |
|
cda309de2 vfs: move MAY_EXE... |
2023 2024 2025 |
err = inode_permission(base->d_inode, MAY_EXEC); if (err) return ERR_PTR(err); |
72bd866a0 fs/namei.c: don't... |
2026 |
return __lookup_hash(&this, base, 0); |
057f6c019 security: prevent... |
2027 |
} |
4d3595073 namei.c: move EXP... |
2028 |
EXPORT_SYMBOL(lookup_one_len); |
057f6c019 security: prevent... |
2029 |
|
1fa1e7f61 readlinkat: ensur... |
2030 2031 |
int user_path_at_empty(int dfd, const char __user *name, unsigned flags, struct path *path, int *empty) |
1da177e4c Linux-2.6.12-rc2 |
2032 |
{ |
2d8f30380 [PATCH] sanitize ... |
2033 |
struct nameidata nd; |
91a27b2a7 vfs: define struc... |
2034 |
struct filename *tmp = getname_flags(name, flags, empty); |
1da177e4c Linux-2.6.12-rc2 |
2035 |
int err = PTR_ERR(tmp); |
1da177e4c Linux-2.6.12-rc2 |
2036 |
if (!IS_ERR(tmp)) { |
2d8f30380 [PATCH] sanitize ... |
2037 2038 |
BUG_ON(flags & LOOKUP_PARENT); |
873f1eedc vfs: turn do_path... |
2039 |
err = filename_lookup(dfd, tmp, flags, &nd); |
1da177e4c Linux-2.6.12-rc2 |
2040 |
putname(tmp); |
2d8f30380 [PATCH] sanitize ... |
2041 2042 |
if (!err) *path = nd.path; |
1da177e4c Linux-2.6.12-rc2 |
2043 2044 2045 |
} return err; } |
1fa1e7f61 readlinkat: ensur... |
2046 2047 2048 |
int user_path_at(int dfd, const char __user *name, unsigned flags, struct path *path) { |
f7493e5d9 vfs: tidy up spar... |
2049 |
return user_path_at_empty(dfd, name, flags, path, NULL); |
1fa1e7f61 readlinkat: ensur... |
2050 |
} |
4d3595073 namei.c: move EXP... |
2051 |
EXPORT_SYMBOL(user_path_at); |
1fa1e7f61 readlinkat: ensur... |
2052 |
|
873f1eedc vfs: turn do_path... |
2053 2054 2055 2056 2057 2058 |
/* * 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... |
2059 |
static struct filename * |
9e790bd65 vfs: add a flags ... |
2060 2061 |
user_path_parent(int dfd, const char __user *path, struct nameidata *nd, unsigned int flags) |
2ad94ae65 [PATCH] new (loca... |
2062 |
{ |
91a27b2a7 vfs: define struc... |
2063 |
struct filename *s = getname(path); |
2ad94ae65 [PATCH] new (loca... |
2064 |
int error; |
9e790bd65 vfs: add a flags ... |
2065 2066 |
/* only LOOKUP_REVAL is allowed in extra flags */ flags &= LOOKUP_REVAL; |
2ad94ae65 [PATCH] new (loca... |
2067 |
if (IS_ERR(s)) |
91a27b2a7 vfs: define struc... |
2068 |
return s; |
2ad94ae65 [PATCH] new (loca... |
2069 |
|
9e790bd65 vfs: add a flags ... |
2070 |
error = filename_lookup(dfd, s, flags | LOOKUP_PARENT, nd); |
91a27b2a7 vfs: define struc... |
2071 |
if (error) { |
2ad94ae65 [PATCH] new (loca... |
2072 |
putname(s); |
91a27b2a7 vfs: define struc... |
2073 2074 |
return ERR_PTR(error); } |
2ad94ae65 [PATCH] new (loca... |
2075 |
|
91a27b2a7 vfs: define struc... |
2076 |
return s; |
2ad94ae65 [PATCH] new (loca... |
2077 |
} |
8033426e6 vfs: allow umount... |
2078 |
/** |
197df04c7 rename user_path_... |
2079 |
* mountpoint_last - look up last component for umount |
8033426e6 vfs: allow umount... |
2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 |
* @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_... |
2106 |
mountpoint_last(struct nameidata *nd, struct path *path) |
8033426e6 vfs: allow umount... |
2107 2108 2109 2110 |
{ int error = 0; struct dentry *dentry; struct dentry *dir = nd->path.dentry; |
35759521e take unlazy_walk(... |
2111 2112 2113 2114 2115 2116 |
/* 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... |
2117 2118 2119 2120 2121 2122 |
} nd->flags &= ~LOOKUP_PARENT; if (unlikely(nd->last_type != LAST_NORM)) { error = handle_dots(nd, nd->last_type); |
35759521e take unlazy_walk(... |
2123 2124 2125 2126 |
if (error) goto out; dentry = dget(nd->path.dentry); goto done; |
8033426e6 vfs: allow umount... |
2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 |
} 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... |
2140 |
mutex_unlock(&dir->d_inode->i_mutex); |
35759521e take unlazy_walk(... |
2141 |
goto out; |
8033426e6 vfs: allow umount... |
2142 |
} |
35759521e take unlazy_walk(... |
2143 2144 |
dentry = lookup_real(dir->d_inode, dentry, nd->flags); error = PTR_ERR(dentry); |
bcceeeba9 Add missing unloc... |
2145 2146 |
if (IS_ERR(dentry)) { mutex_unlock(&dir->d_inode->i_mutex); |
35759521e take unlazy_walk(... |
2147 |
goto out; |
bcceeeba9 Add missing unloc... |
2148 |
} |
8033426e6 vfs: allow umount... |
2149 2150 |
} mutex_unlock(&dir->d_inode->i_mutex); |
35759521e take unlazy_walk(... |
2151 2152 2153 2154 2155 |
done: if (!dentry->d_inode) { error = -ENOENT; dput(dentry); goto out; |
8033426e6 vfs: allow umount... |
2156 |
} |
35759521e take unlazy_walk(... |
2157 2158 |
path->dentry = dentry; path->mnt = mntget(nd->path.mnt); |
b18825a7c VFS: Put a small ... |
2159 |
if (should_follow_link(dentry, nd->flags & LOOKUP_FOLLOW)) |
35759521e take unlazy_walk(... |
2160 2161 2162 2163 |
return 1; follow_mount(path); error = 0; out: |
8033426e6 vfs: allow umount... |
2164 2165 2166 2167 2168 |
terminate_walk(nd); return error; } /** |
197df04c7 rename user_path_... |
2169 |
* path_mountpoint - look up a path to be umounted |
8033426e6 vfs: allow umount... |
2170 2171 |
* @dfd: directory file descriptor to start walk from * @name: full pathname to walk |
606d6fe3f fs/namei.c: fix n... |
2172 |
* @path: pointer to container for result |
8033426e6 vfs: allow umount... |
2173 |
* @flags: lookup flags |
8033426e6 vfs: allow umount... |
2174 2175 |
* * Look up the given name, but don't attempt to revalidate the last component. |
606d6fe3f fs/namei.c: fix n... |
2176 |
* Returns 0 and "path" will be valid on success; Returns error otherwise. |
8033426e6 vfs: allow umount... |
2177 2178 |
*/ static int |
197df04c7 rename user_path_... |
2179 |
path_mountpoint(int dfd, const char *name, struct path *path, unsigned int flags) |
8033426e6 vfs: allow umount... |
2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 |
{ 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_... |
2193 |
err = mountpoint_last(&nd, path); |
8033426e6 vfs: allow umount... |
2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 |
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_... |
2204 |
err = mountpoint_last(&nd, path); |
8033426e6 vfs: allow umount... |
2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 |
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... |
2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 |
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... |
2229 |
/** |
197df04c7 rename user_path_... |
2230 |
* user_path_mountpoint_at - lookup a path from userland in order to umount it |
8033426e6 vfs: allow umount... |
2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 |
* @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_... |
2244 |
user_path_mountpoint_at(int dfd, const char __user *name, unsigned int flags, |
8033426e6 vfs: allow umount... |
2245 2246 2247 2248 |
struct path *path) { struct filename *s = getname(name); int error; |
8033426e6 vfs: allow umount... |
2249 2250 |
if (IS_ERR(s)) return PTR_ERR(s); |
2d8646510 introduce kern_pa... |
2251 |
error = filename_mountpoint(dfd, s, path, flags); |
8033426e6 vfs: allow umount... |
2252 2253 2254 |
putname(s); return error; } |
2d8646510 introduce kern_pa... |
2255 2256 2257 2258 2259 2260 2261 2262 |
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 |
2263 2264 2265 2266 2267 2268 |
/* * 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... |
2269 |
kuid_t fsuid = current_fsuid(); |
da9592ede CRED: Wrap task c... |
2270 |
|
1da177e4c Linux-2.6.12-rc2 |
2271 2272 |
if (!(dir->i_mode & S_ISVTX)) return 0; |
8e96e3b7b userns: Use uid_e... |
2273 |
if (uid_eq(inode->i_uid, fsuid)) |
1da177e4c Linux-2.6.12-rc2 |
2274 |
return 0; |
8e96e3b7b userns: Use uid_e... |
2275 |
if (uid_eq(dir->i_uid, fsuid)) |
1da177e4c Linux-2.6.12-rc2 |
2276 |
return 0; |
1a48e2ac0 userns: Replace t... |
2277 |
return !inode_capable(inode, CAP_FOWNER); |
1da177e4c Linux-2.6.12-rc2 |
2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 |
} /* * 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 ... |
2299 |
static int may_delete(struct inode *dir, struct dentry *victim, bool isdir) |
1da177e4c Linux-2.6.12-rc2 |
2300 |
{ |
b18825a7c VFS: Put a small ... |
2301 |
struct inode *inode = victim->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
2302 |
int error; |
b18825a7c VFS: Put a small ... |
2303 |
if (d_is_negative(victim)) |
1da177e4c Linux-2.6.12-rc2 |
2304 |
return -ENOENT; |
b18825a7c VFS: Put a small ... |
2305 |
BUG_ON(!inode); |
1da177e4c Linux-2.6.12-rc2 |
2306 2307 |
BUG_ON(victim->d_parent->d_inode != dir); |
4fa6b5ecb audit: overhaul _... |
2308 |
audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE); |
1da177e4c Linux-2.6.12-rc2 |
2309 |
|
f419a2e3b [PATCH] kill name... |
2310 |
error = inode_permission(dir, MAY_WRITE | MAY_EXEC); |
1da177e4c Linux-2.6.12-rc2 |
2311 2312 2313 2314 |
if (error) return error; if (IS_APPEND(dir)) return -EPERM; |
b18825a7c VFS: Put a small ... |
2315 2316 2317 |
if (check_sticky(dir, inode) || IS_APPEND(inode) || IS_IMMUTABLE(inode) || IS_SWAPFILE(inode)) |
1da177e4c Linux-2.6.12-rc2 |
2318 2319 |
return -EPERM; if (isdir) { |
44b1d5304 vfs: add d_is_dir() |
2320 |
if (!d_is_dir(victim)) |
1da177e4c Linux-2.6.12-rc2 |
2321 2322 2323 |
return -ENOTDIR; if (IS_ROOT(victim)) return -EBUSY; |
44b1d5304 vfs: add d_is_dir() |
2324 |
} else if (d_is_dir(victim)) |
1da177e4c Linux-2.6.12-rc2 |
2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 |
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: ... |
2341 |
static inline int may_create(struct inode *dir, struct dentry *child) |
1da177e4c Linux-2.6.12-rc2 |
2342 |
{ |
14e972b45 audit: add child ... |
2343 |
audit_inode_child(dir, child, AUDIT_TYPE_CHILD_CREATE); |
1da177e4c Linux-2.6.12-rc2 |
2344 2345 2346 2347 |
if (child->d_inode) return -EEXIST; if (IS_DEADDIR(dir)) return -ENOENT; |
f419a2e3b [PATCH] kill name... |
2348 |
return inode_permission(dir, MAY_WRITE | MAY_EXEC); |
1da177e4c Linux-2.6.12-rc2 |
2349 |
} |
1da177e4c Linux-2.6.12-rc2 |
2350 2351 2352 2353 2354 2355 2356 2357 |
/* * 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: ... |
2358 |
mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT); |
1da177e4c Linux-2.6.12-rc2 |
2359 2360 |
return NULL; } |
a11f3a057 [PATCH] sem2mutex... |
2361 |
mutex_lock(&p1->d_inode->i_sb->s_vfs_rename_mutex); |
1da177e4c Linux-2.6.12-rc2 |
2362 |
|
e2761a116 [PATCH vfs-2.6 2/... |
2363 2364 2365 2366 2367 |
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 |
2368 |
} |
e2761a116 [PATCH vfs-2.6 2/... |
2369 2370 2371 2372 2373 |
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 |
2374 |
} |
f2eace23e [PATCH] lockdep: ... |
2375 2376 |
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 |
2377 2378 |
return NULL; } |
4d3595073 namei.c: move EXP... |
2379 |
EXPORT_SYMBOL(lock_rename); |
1da177e4c Linux-2.6.12-rc2 |
2380 2381 2382 |
void unlock_rename(struct dentry *p1, struct dentry *p2) { |
1b1dcc1b5 [PATCH] mutex sub... |
2383 |
mutex_unlock(&p1->d_inode->i_mutex); |
1da177e4c Linux-2.6.12-rc2 |
2384 |
if (p1 != p2) { |
1b1dcc1b5 [PATCH] mutex sub... |
2385 |
mutex_unlock(&p2->d_inode->i_mutex); |
a11f3a057 [PATCH] sem2mutex... |
2386 |
mutex_unlock(&p1->d_inode->i_sb->s_vfs_rename_mutex); |
1da177e4c Linux-2.6.12-rc2 |
2387 2388 |
} } |
4d3595073 namei.c: move EXP... |
2389 |
EXPORT_SYMBOL(unlock_rename); |
1da177e4c Linux-2.6.12-rc2 |
2390 |
|
4acdaf27e switch ->create()... |
2391 |
int vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, |
312b63fba don't pass nameid... |
2392 |
bool want_excl) |
1da177e4c Linux-2.6.12-rc2 |
2393 |
{ |
a95164d97 [patch 3/4] vfs: ... |
2394 |
int error = may_create(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
2395 2396 |
if (error) return error; |
acfa4380e inode->i_op is ne... |
2397 |
if (!dir->i_op->create) |
1da177e4c Linux-2.6.12-rc2 |
2398 2399 2400 2401 2402 2403 |
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... |
2404 |
error = dir->i_op->create(dir, dentry, mode, want_excl); |
a74574aaf [PATCH] Remove se... |
2405 |
if (!error) |
f38aa9422 [PATCH] Pass dent... |
2406 |
fsnotify_create(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
2407 2408 |
return error; } |
4d3595073 namei.c: move EXP... |
2409 |
EXPORT_SYMBOL(vfs_create); |
1da177e4c Linux-2.6.12-rc2 |
2410 |
|
73d049a40 open-style analog... |
2411 |
static int may_open(struct path *path, int acc_mode, int flag) |
1da177e4c Linux-2.6.12-rc2 |
2412 |
{ |
3fb64190a pass a struct pat... |
2413 |
struct dentry *dentry = path->dentry; |
1da177e4c Linux-2.6.12-rc2 |
2414 2415 |
struct inode *inode = dentry->d_inode; int error; |
bcda76524 Allow O_PATH for ... |
2416 2417 2418 |
/* O_PATH? */ if (!acc_mode) return 0; |
1da177e4c Linux-2.6.12-rc2 |
2419 2420 |
if (!inode) return -ENOENT; |
c8fe8f30c cleanup may_open |
2421 2422 |
switch (inode->i_mode & S_IFMT) { case S_IFLNK: |
1da177e4c Linux-2.6.12-rc2 |
2423 |
return -ELOOP; |
c8fe8f30c cleanup may_open |
2424 2425 2426 2427 2428 2429 |
case S_IFDIR: if (acc_mode & MAY_WRITE) return -EISDIR; break; case S_IFBLK: case S_IFCHR: |
3fb64190a pass a struct pat... |
2430 |
if (path->mnt->mnt_flags & MNT_NODEV) |
1da177e4c Linux-2.6.12-rc2 |
2431 |
return -EACCES; |
c8fe8f30c cleanup may_open |
2432 2433 2434 |
/*FALLTHRU*/ case S_IFIFO: case S_IFSOCK: |
1da177e4c Linux-2.6.12-rc2 |
2435 |
flag &= ~O_TRUNC; |
c8fe8f30c cleanup may_open |
2436 |
break; |
4a3fd211c [PATCH] r/o bind ... |
2437 |
} |
b41572e92 r/o bind mounts: ... |
2438 |
|
3fb64190a pass a struct pat... |
2439 |
error = inode_permission(inode, acc_mode); |
b41572e92 r/o bind mounts: ... |
2440 2441 |
if (error) return error; |
6146f0d5e integrity: IMA hooks |
2442 |
|
1da177e4c Linux-2.6.12-rc2 |
2443 2444 2445 2446 |
/* * An append-only file must be opened in append mode for writing. */ if (IS_APPEND(inode)) { |
8737c9305 Switch may_open()... |
2447 |
if ((flag & O_ACCMODE) != O_RDONLY && !(flag & O_APPEND)) |
7715b5212 O_TRUNC open shou... |
2448 |
return -EPERM; |
1da177e4c Linux-2.6.12-rc2 |
2449 |
if (flag & O_TRUNC) |
7715b5212 O_TRUNC open shou... |
2450 |
return -EPERM; |
1da177e4c Linux-2.6.12-rc2 |
2451 2452 2453 |
} /* O_NOATIME can only be set by the owner or superuser */ |
2e1496707 userns: rename is... |
2454 |
if (flag & O_NOATIME && !inode_owner_or_capable(inode)) |
7715b5212 O_TRUNC open shou... |
2455 |
return -EPERM; |
1da177e4c Linux-2.6.12-rc2 |
2456 |
|
f3c7691e8 leases: fix write... |
2457 |
return 0; |
7715b5212 O_TRUNC open shou... |
2458 |
} |
1da177e4c Linux-2.6.12-rc2 |
2459 |
|
e1181ee65 vfs: pass struct ... |
2460 |
static int handle_truncate(struct file *filp) |
7715b5212 O_TRUNC open shou... |
2461 |
{ |
e1181ee65 vfs: pass struct ... |
2462 |
struct path *path = &filp->f_path; |
7715b5212 O_TRUNC open shou... |
2463 2464 2465 2466 2467 2468 2469 |
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_... |
2470 |
error = locks_verify_locked(filp); |
7715b5212 O_TRUNC open shou... |
2471 |
if (!error) |
ea0d3ab23 LSM: Remove unuse... |
2472 |
error = security_path_truncate(path); |
7715b5212 O_TRUNC open shou... |
2473 2474 2475 |
if (!error) { error = do_truncate(path->dentry, 0, ATTR_MTIME|ATTR_CTIME|ATTR_OPEN, |
e1181ee65 vfs: pass struct ... |
2476 |
filp); |
7715b5212 O_TRUNC open shou... |
2477 2478 |
} put_write_access(inode); |
acd0c9351 IMA: update ima_c... |
2479 |
return error; |
1da177e4c Linux-2.6.12-rc2 |
2480 |
} |
d57999e15 [PATCH] do namei_... |
2481 2482 |
static inline int open_to_namei_flags(int flag) { |
8a5e929dd don't translitera... |
2483 2484 |
if ((flag & O_ACCMODE) == 3) flag--; |
d57999e15 [PATCH] do namei_... |
2485 2486 |
return flag; } |
d18e9008c vfs: add i_op->at... |
2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 |
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... |
2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 |
/* * 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... |
2512 2513 2514 |
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... |
2515 |
bool got_write, bool need_lookup, |
2675a4eb6 fs/namei.c: get d... |
2516 |
int *opened) |
d18e9008c vfs: add i_op->at... |
2517 2518 2519 2520 2521 2522 |
{ 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... |
2523 2524 |
int create_error = 0; struct dentry *const DENTRY_NOT_SET = (void *) -1UL; |
116cc0225 vfs: don't set FI... |
2525 |
bool excl; |
d18e9008c vfs: add i_op->at... |
2526 2527 2528 2529 2530 |
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... |
2531 |
error = -ENOENT; |
d18e9008c vfs: add i_op->at... |
2532 2533 |
goto out; } |
62b259d8b vfs: atomic_open(... |
2534 |
mode = op->mode; |
d18e9008c vfs: add i_op->at... |
2535 2536 |
if ((open_flag & O_CREAT) && !IS_POSIXACL(dir)) mode &= ~current_umask(); |
116cc0225 vfs: don't set FI... |
2537 2538 |
excl = (open_flag & (O_EXCL | O_CREAT)) == (O_EXCL | O_CREAT); if (excl) |
d18e9008c vfs: add i_op->at... |
2539 |
open_flag &= ~O_TRUNC; |
d18e9008c vfs: add i_op->at... |
2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 |
/* * 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... |
2550 2551 2552 |
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... |
2553 2554 2555 2556 2557 2558 2559 |
/* * 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... |
2560 |
create_error = -EROFS; |
d18e9008c vfs: add i_op->at... |
2561 2562 2563 |
goto no_open; } else { /* No side effects, safe to clear O_CREAT */ |
64894cf84 simplify lookup_o... |
2564 |
create_error = -EROFS; |
d18e9008c vfs: add i_op->at... |
2565 2566 2567 2568 2569 |
open_flag &= ~O_CREAT; } } if (open_flag & O_CREAT) { |
38227f78a vfs: pass right c... |
2570 |
error = may_o_create(&nd->path, dentry, mode); |
d18e9008c vfs: add i_op->at... |
2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 |
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 |
2581 2582 2583 |
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... |
2584 |
opened); |
d95852777 make ->atomic_ope... |
2585 |
if (error < 0) { |
d95852777 make ->atomic_ope... |
2586 2587 |
if (create_error && error == -ENOENT) error = create_error; |
d18e9008c vfs: add i_op->at... |
2588 2589 |
goto out; } |
d95852777 make ->atomic_ope... |
2590 |
if (error) { /* returned 1, that is */ |
30d904947 kill struct opendata |
2591 |
if (WARN_ON(file->f_path.dentry == DENTRY_NOT_SET)) { |
2675a4eb6 fs/namei.c: get d... |
2592 |
error = -EIO; |
d18e9008c vfs: add i_op->at... |
2593 2594 |
goto out; } |
30d904947 kill struct opendata |
2595 |
if (file->f_path.dentry) { |
d18e9008c vfs: add i_op->at... |
2596 |
dput(dentry); |
30d904947 kill struct opendata |
2597 |
dentry = file->f_path.dentry; |
d18e9008c vfs: add i_op->at... |
2598 |
} |
03da633aa atomic_open: take... |
2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 |
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... |
2612 |
} |
d18e9008c vfs: add i_op->at... |
2613 2614 2615 2616 2617 2618 2619 |
goto looked_up; } /* * We didn't have the inode before the open, so check open permission * here. */ |
03da633aa atomic_open: take... |
2620 2621 2622 2623 2624 2625 |
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... |
2626 2627 2628 |
error = may_open(&file->f_path, acc_mode, open_flag); if (error) fput(file); |
d18e9008c vfs: add i_op->at... |
2629 2630 2631 |
out: dput(dentry); |
2675a4eb6 fs/namei.c: get d... |
2632 |
return error; |
d18e9008c vfs: add i_op->at... |
2633 |
|
d18e9008c vfs: add i_op->at... |
2634 2635 |
no_open: if (need_lookup) { |
72bd866a0 fs/namei.c: don't... |
2636 |
dentry = lookup_real(dir, dentry, nd->flags); |
d18e9008c vfs: add i_op->at... |
2637 |
if (IS_ERR(dentry)) |
2675a4eb6 fs/namei.c: get d... |
2638 |
return PTR_ERR(dentry); |
d18e9008c vfs: add i_op->at... |
2639 2640 2641 |
if (create_error) { int open_flag = op->open_flag; |
2675a4eb6 fs/namei.c: get d... |
2642 |
error = create_error; |
d18e9008c vfs: add i_op->at... |
2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 |
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... |
2658 |
return 1; |
d18e9008c vfs: add i_op->at... |
2659 |
} |
31e6b01f4 fs: rcu-walk for ... |
2660 |
/* |
1acf0af9b VFS: Fix the bann... |
2661 |
* Look up and maybe create and open the last component. |
d58ffd35c vfs: add lookup_o... |
2662 2663 2664 |
* * Must be called with i_mutex held on parent. * |
1acf0af9b VFS: Fix the bann... |
2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 |
* 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... |
2677 |
*/ |
2675a4eb6 fs/namei.c: get d... |
2678 2679 2680 |
static int lookup_open(struct nameidata *nd, struct path *path, struct file *file, const struct open_flags *op, |
64894cf84 simplify lookup_o... |
2681 |
bool got_write, int *opened) |
d58ffd35c vfs: add lookup_o... |
2682 2683 |
{ struct dentry *dir = nd->path.dentry; |
54ef48724 vfs: lookup_open(... |
2684 |
struct inode *dir_inode = dir->d_inode; |
d58ffd35c vfs: add lookup_o... |
2685 2686 |
struct dentry *dentry; int error; |
54ef48724 vfs: lookup_open(... |
2687 |
bool need_lookup; |
d58ffd35c vfs: add lookup_o... |
2688 |
|
47237687d ->atomic_open() p... |
2689 |
*opened &= ~FILE_CREATED; |
201f956e4 fs/namei.c: don't... |
2690 |
dentry = lookup_dcache(&nd->last, dir, nd->flags, &need_lookup); |
d58ffd35c vfs: add lookup_o... |
2691 |
if (IS_ERR(dentry)) |
2675a4eb6 fs/namei.c: get d... |
2692 |
return PTR_ERR(dentry); |
d58ffd35c vfs: add lookup_o... |
2693 |
|
d18e9008c vfs: add i_op->at... |
2694 2695 2696 2697 2698 |
/* 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... |
2699 |
return atomic_open(nd, dentry, path, file, op, got_write, |
47237687d ->atomic_open() p... |
2700 |
need_lookup, opened); |
d18e9008c vfs: add i_op->at... |
2701 |
} |
54ef48724 vfs: lookup_open(... |
2702 2703 |
if (need_lookup) { BUG_ON(dentry->d_inode); |
72bd866a0 fs/namei.c: don't... |
2704 |
dentry = lookup_real(dir_inode, dentry, nd->flags); |
54ef48724 vfs: lookup_open(... |
2705 |
if (IS_ERR(dentry)) |
2675a4eb6 fs/namei.c: get d... |
2706 |
return PTR_ERR(dentry); |
54ef48724 vfs: lookup_open(... |
2707 |
} |
d58ffd35c vfs: add lookup_o... |
2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 |
/* 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 ... |
2718 |
* the 'struct file' in finish_open(). |
d58ffd35c vfs: add lookup_o... |
2719 |
*/ |
64894cf84 simplify lookup_o... |
2720 2721 |
if (!got_write) { error = -EROFS; |
d58ffd35c vfs: add lookup_o... |
2722 |
goto out_dput; |
64894cf84 simplify lookup_o... |
2723 |
} |
47237687d ->atomic_open() p... |
2724 |
*opened |= FILE_CREATED; |
d58ffd35c vfs: add lookup_o... |
2725 2726 2727 |
error = security_path_mknod(&nd->path, dentry, mode, 0); if (error) goto out_dput; |
312b63fba don't pass nameid... |
2728 2729 |
error = vfs_create(dir->d_inode, dentry, mode, nd->flags & LOOKUP_EXCL); |
d58ffd35c vfs: add lookup_o... |
2730 2731 2732 |
if (error) goto out_dput; } |
d18e9008c vfs: add i_op->at... |
2733 |
out_no_open: |
d58ffd35c vfs: add lookup_o... |
2734 2735 |
path->dentry = dentry; path->mnt = nd->path.mnt; |
2675a4eb6 fs/namei.c: get d... |
2736 |
return 1; |
d58ffd35c vfs: add lookup_o... |
2737 2738 2739 |
out_dput: dput(dentry); |
2675a4eb6 fs/namei.c: get d... |
2740 |
return error; |
d58ffd35c vfs: add lookup_o... |
2741 2742 2743 |
} /* |
fe2d35ff0 switch non-create... |
2744 |
* Handle the last step of open() |
31e6b01f4 fs: rcu-walk for ... |
2745 |
*/ |
2675a4eb6 fs/namei.c: get d... |
2746 2747 |
static int do_last(struct nameidata *nd, struct path *path, struct file *file, const struct open_flags *op, |
669abf4e5 vfs: make path_op... |
2748 |
int *opened, struct filename *name) |
fb1cc555d gut do_filp_open(... |
2749 |
{ |
a1e28038d pull the common p... |
2750 |
struct dentry *dir = nd->path.dentry; |
ca344a894 do_last: unify ma... |
2751 |
int open_flag = op->open_flag; |
77d660a8a vfs: do_last(): c... |
2752 |
bool will_truncate = (open_flag & O_TRUNC) != 0; |
64894cf84 simplify lookup_o... |
2753 |
bool got_write = false; |
bcda76524 Allow O_PATH for ... |
2754 |
int acc_mode = op->acc_mode; |
a1eb33153 vfs: do_last(): i... |
2755 |
struct inode *inode; |
77d660a8a vfs: do_last(): c... |
2756 |
bool symlink_ok = false; |
16b1c1cd7 vfs: retry last c... |
2757 2758 |
struct path save_parent = { .dentry = NULL, .mnt = NULL }; bool retried = false; |
16c2cd717 untangle the "nee... |
2759 |
int error; |
1f36f774b Switch !O_CREAT c... |
2760 |
|
c3e380b0b Collect "operatio... |
2761 2762 |
nd->flags &= ~LOOKUP_PARENT; nd->flags |= op->intent; |
bc77daa78 do_last(): fix mi... |
2763 |
if (nd->last_type != LAST_NORM) { |
fe2d35ff0 switch non-create... |
2764 2765 |
error = handle_dots(nd, nd->last_type); if (error) |
2675a4eb6 fs/namei.c: get d... |
2766 |
return error; |
e83db1672 vfs: do_last(): c... |
2767 |
goto finish_open; |
1f36f774b Switch !O_CREAT c... |
2768 |
} |
67ee3ad21 Pull handling of ... |
2769 |
|
ca344a894 do_last: unify ma... |
2770 |
if (!(open_flag & O_CREAT)) { |
fe2d35ff0 switch non-create... |
2771 2772 |
if (nd->last.name[nd->last.len]) nd->flags |= LOOKUP_FOLLOW | LOOKUP_DIRECTORY; |
bcda76524 Allow O_PATH for ... |
2773 |
if (open_flag & O_PATH && !(nd->flags & LOOKUP_FOLLOW)) |
77d660a8a vfs: do_last(): c... |
2774 |
symlink_ok = true; |
fe2d35ff0 switch non-create... |
2775 |
/* we _can_ be in RCU mode here */ |
e97cdc87b lookup_fast: get ... |
2776 |
error = lookup_fast(nd, path, &inode); |
715748654 vfs: do_last(): c... |
2777 2778 2779 2780 |
if (likely(!error)) goto finish_lookup; if (error < 0) |
2675a4eb6 fs/namei.c: get d... |
2781 |
goto out; |
715748654 vfs: do_last(): c... |
2782 2783 |
BUG_ON(nd->inode != dir->d_inode); |
b6183df7b vfs: do_last(): s... |
2784 2785 2786 2787 2788 2789 2790 2791 2792 |
} 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... |
2793 |
return error; |
fe2d35ff0 switch non-create... |
2794 |
|
33e2208ac audit: vfs: fix a... |
2795 |
audit_inode(name, dir, LOOKUP_PARENT); |
b6183df7b vfs: do_last(): s... |
2796 2797 2798 |
error = -EISDIR; /* trailing slashes? */ if (nd->last.name[nd->last.len]) |
2675a4eb6 fs/namei.c: get d... |
2799 |
goto out; |
b6183df7b vfs: do_last(): s... |
2800 |
} |
a2c36b450 pull more into do... |
2801 |
|
16b1c1cd7 vfs: retry last c... |
2802 |
retry_lookup: |
64894cf84 simplify lookup_o... |
2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 |
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... |
2813 |
mutex_lock(&dir->d_inode->i_mutex); |
64894cf84 simplify lookup_o... |
2814 |
error = lookup_open(nd, path, file, op, got_write, opened); |
d58ffd35c vfs: add lookup_o... |
2815 |
mutex_unlock(&dir->d_inode->i_mutex); |
a1e28038d pull the common p... |
2816 |
|
2675a4eb6 fs/namei.c: get d... |
2817 2818 |
if (error <= 0) { if (error) |
d18e9008c vfs: add i_op->at... |
2819 |
goto out; |
47237687d ->atomic_open() p... |
2820 |
if ((*opened & FILE_CREATED) || |
496ad9aa8 new helper: file_... |
2821 |
!S_ISREG(file_inode(file)->i_mode)) |
77d660a8a vfs: do_last(): c... |
2822 |
will_truncate = false; |
d18e9008c vfs: add i_op->at... |
2823 |
|
adb5c2473 audit: make audit... |
2824 |
audit_inode(name, file->f_path.dentry, 0); |
d18e9008c vfs: add i_op->at... |
2825 2826 |
goto opened; } |
fb1cc555d gut do_filp_open(... |
2827 |
|
47237687d ->atomic_open() p... |
2828 |
if (*opened & FILE_CREATED) { |
9b44f1b39 move may_open() f... |
2829 |
/* Don't check for write permission, don't truncate */ |
ca344a894 do_last: unify ma... |
2830 |
open_flag &= ~O_TRUNC; |
77d660a8a vfs: do_last(): c... |
2831 |
will_truncate = false; |
bcda76524 Allow O_PATH for ... |
2832 |
acc_mode = MAY_OPEN; |
d58ffd35c vfs: add lookup_o... |
2833 |
path_to_nameidata(path, nd); |
e83db1672 vfs: do_last(): c... |
2834 |
goto finish_open_created; |
fb1cc555d gut do_filp_open(... |
2835 2836 2837 |
} /* |
3134f37e9 vfs: don't let do... |
2838 |
* create/update audit record if it already exists. |
fb1cc555d gut do_filp_open(... |
2839 |
*/ |
b18825a7c VFS: Put a small ... |
2840 |
if (d_is_positive(path->dentry)) |
adb5c2473 audit: make audit... |
2841 |
audit_inode(name, path->dentry, 0); |
fb1cc555d gut do_filp_open(... |
2842 |
|
d18e9008c vfs: add i_op->at... |
2843 2844 2845 2846 2847 |
/* * 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... |
2848 |
if (got_write) { |
d18e9008c vfs: add i_op->at... |
2849 |
mnt_drop_write(nd->path.mnt); |
64894cf84 simplify lookup_o... |
2850 |
got_write = false; |
d18e9008c vfs: add i_op->at... |
2851 |
} |
fb1cc555d gut do_filp_open(... |
2852 |
error = -EEXIST; |
f8310c592 fix O_EXCL handli... |
2853 |
if ((open_flag & (O_EXCL | O_CREAT)) == (O_EXCL | O_CREAT)) |
fb1cc555d gut do_filp_open(... |
2854 |
goto exit_dput; |
9875cf806 Add a dentry op t... |
2855 2856 2857 |
error = follow_managed(path, nd->flags); if (error < 0) goto exit_dput; |
fb1cc555d gut do_filp_open(... |
2858 |
|
a3fbbde70 VFS: we need to s... |
2859 2860 |
if (error) nd->flags |= LOOKUP_JUMPED; |
decf34008 vfs: do_last(): u... |
2861 2862 |
BUG_ON(nd->flags & LOOKUP_RCU); inode = path->dentry->d_inode; |
5f5daac12 vfs: do_last() co... |
2863 2864 |
finish_lookup: /* we _can_ be in RCU mode here */ |
fb1cc555d gut do_filp_open(... |
2865 |
error = -ENOENT; |
b18825a7c VFS: Put a small ... |
2866 |
if (d_is_negative(path->dentry)) { |
54c33e7f9 vfs: do_last(): m... |
2867 |
path_to_nameidata(path, nd); |
2675a4eb6 fs/namei.c: get d... |
2868 |
goto out; |
54c33e7f9 vfs: do_last(): m... |
2869 |
} |
9e67f3616 Kill is_link argu... |
2870 |
|
b18825a7c VFS: Put a small ... |
2871 |
if (should_follow_link(path->dentry, !symlink_ok)) { |
d45ea8679 vfs: make follow_... |
2872 2873 2874 |
if (nd->flags & LOOKUP_RCU) { if (unlikely(unlazy_walk(nd, path->dentry))) { error = -ECHILD; |
2675a4eb6 fs/namei.c: get d... |
2875 |
goto out; |
d45ea8679 vfs: make follow_... |
2876 2877 2878 |
} } BUG_ON(inode != path->dentry->d_inode); |
2675a4eb6 fs/namei.c: get d... |
2879 |
return 1; |
d45ea8679 vfs: make follow_... |
2880 |
} |
fb1cc555d gut do_filp_open(... |
2881 |
|
16b1c1cd7 vfs: retry last c... |
2882 2883 2884 2885 2886 2887 2888 2889 |
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... |
2890 |
nd->inode = inode; |
a3fbbde70 VFS: we need to s... |
2891 |
/* Why this, you ask? _Now_ we might have grown LOOKUP_JUMPED... */ |
bc77daa78 do_last(): fix mi... |
2892 |
finish_open: |
a3fbbde70 VFS: we need to s... |
2893 |
error = complete_walk(nd); |
16b1c1cd7 vfs: retry last c... |
2894 2895 |
if (error) { path_put(&save_parent); |
2675a4eb6 fs/namei.c: get d... |
2896 |
return error; |
16b1c1cd7 vfs: retry last c... |
2897 |
} |
bc77daa78 do_last(): fix mi... |
2898 |
audit_inode(name, nd->path.dentry, 0); |
fb1cc555d gut do_filp_open(... |
2899 |
error = -EISDIR; |
44b1d5304 vfs: add d_is_dir() |
2900 |
if ((open_flag & O_CREAT) && d_is_dir(nd->path.dentry)) |
2675a4eb6 fs/namei.c: get d... |
2901 |
goto out; |
af2f55426 vfs: do_last(): c... |
2902 |
error = -ENOTDIR; |
44b1d5304 vfs: add d_is_dir() |
2903 |
if ((nd->flags & LOOKUP_DIRECTORY) && !d_can_lookup(nd->path.dentry)) |
2675a4eb6 fs/namei.c: get d... |
2904 |
goto out; |
6c0d46c49 fold __open_namei... |
2905 |
if (!S_ISREG(nd->inode->i_mode)) |
77d660a8a vfs: do_last(): c... |
2906 |
will_truncate = false; |
6c0d46c49 fold __open_namei... |
2907 |
|
0f9d1a10c expand finish_ope... |
2908 2909 2910 |
if (will_truncate) { error = mnt_want_write(nd->path.mnt); if (error) |
2675a4eb6 fs/namei.c: get d... |
2911 |
goto out; |
64894cf84 simplify lookup_o... |
2912 |
got_write = true; |
0f9d1a10c expand finish_ope... |
2913 |
} |
e83db1672 vfs: do_last(): c... |
2914 |
finish_open_created: |
bcda76524 Allow O_PATH for ... |
2915 |
error = may_open(&nd->path, acc_mode, open_flag); |
ca344a894 do_last: unify ma... |
2916 |
if (error) |
2675a4eb6 fs/namei.c: get d... |
2917 |
goto out; |
30d904947 kill struct opendata |
2918 2919 2920 |
file->f_path.mnt = nd->path.mnt; error = finish_open(file, nd->path.dentry, NULL, opened); if (error) { |
30d904947 kill struct opendata |
2921 |
if (error == -EOPENSTALE) |
f60dc3db6 vfs: do_last(): c... |
2922 |
goto stale_open; |
015c3bbcd vfs: remove open ... |
2923 |
goto out; |
f60dc3db6 vfs: do_last(): c... |
2924 |
} |
a8277b9ba vfs: move O_DIREC... |
2925 |
opened: |
2675a4eb6 fs/namei.c: get d... |
2926 |
error = open_check_o_direct(file); |
015c3bbcd vfs: remove open ... |
2927 2928 |
if (error) goto exit_fput; |
2675a4eb6 fs/namei.c: get d... |
2929 |
error = ima_file_check(file, op->acc_mode); |
aa4caadb7 vfs: do_last(): c... |
2930 2931 2932 2933 |
if (error) goto exit_fput; if (will_truncate) { |
2675a4eb6 fs/namei.c: get d... |
2934 |
error = handle_truncate(file); |
aa4caadb7 vfs: do_last(): c... |
2935 2936 |
if (error) goto exit_fput; |
0f9d1a10c expand finish_ope... |
2937 |
} |
ca344a894 do_last: unify ma... |
2938 |
out: |
64894cf84 simplify lookup_o... |
2939 |
if (got_write) |
0f9d1a10c expand finish_ope... |
2940 |
mnt_drop_write(nd->path.mnt); |
16b1c1cd7 vfs: retry last c... |
2941 |
path_put(&save_parent); |
e276ae672 vfs: do_last(): m... |
2942 |
terminate_walk(nd); |
2675a4eb6 fs/namei.c: get d... |
2943 |
return error; |
fb1cc555d gut do_filp_open(... |
2944 |
|
fb1cc555d gut do_filp_open(... |
2945 2946 |
exit_dput: path_put_conditional(path, nd); |
ca344a894 do_last: unify ma... |
2947 |
goto out; |
015c3bbcd vfs: remove open ... |
2948 |
exit_fput: |
2675a4eb6 fs/namei.c: get d... |
2949 2950 |
fput(file); goto out; |
015c3bbcd vfs: remove open ... |
2951 |
|
f60dc3db6 vfs: do_last(): c... |
2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 |
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... |
2963 |
if (got_write) { |
f60dc3db6 vfs: do_last(): c... |
2964 |
mnt_drop_write(nd->path.mnt); |
64894cf84 simplify lookup_o... |
2965 |
got_write = false; |
f60dc3db6 vfs: do_last(): c... |
2966 2967 2968 |
} retried = true; goto retry_lookup; |
fb1cc555d gut do_filp_open(... |
2969 |
} |
60545d0d4 [O_TMPFILE] it's ... |
2970 2971 2972 2973 2974 2975 2976 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 |
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... |
3016 |
if (error) { |
60545d0d4 [O_TMPFILE] it's ... |
3017 |
fput(file); |
f4e0c30c1 allow the temp fi... |
3018 3019 3020 3021 3022 3023 |
} 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 ... |
3024 3025 3026 3027 3028 3029 |
out2: mnt_drop_write(nd->path.mnt); out: path_put(&nd->path); return error; } |
669abf4e5 vfs: make path_op... |
3030 |
static struct file *path_openat(int dfd, struct filename *pathname, |
73d049a40 open-style analog... |
3031 |
struct nameidata *nd, const struct open_flags *op, int flags) |
1da177e4c Linux-2.6.12-rc2 |
3032 |
{ |
fe2d35ff0 switch non-create... |
3033 |
struct file *base = NULL; |
30d904947 kill struct opendata |
3034 |
struct file *file; |
9850c0565 Fix the -ESTALE h... |
3035 |
struct path path; |
47237687d ->atomic_open() p... |
3036 |
int opened = 0; |
13aab428a separate -ESTALE/... |
3037 |
int error; |
31e6b01f4 fs: rcu-walk for ... |
3038 |
|
30d904947 kill struct opendata |
3039 |
file = get_empty_filp(); |
1afc99bea propagate error f... |
3040 3041 |
if (IS_ERR(file)) return file; |
31e6b01f4 fs: rcu-walk for ... |
3042 |
|
30d904947 kill struct opendata |
3043 |
file->f_flags = op->open_flag; |
31e6b01f4 fs: rcu-walk for ... |
3044 |
|
bb458c644 Safer ABI for O_T... |
3045 |
if (unlikely(file->f_flags & __O_TMPFILE)) { |
60545d0d4 [O_TMPFILE] it's ... |
3046 3047 3048 |
error = do_tmpfile(dfd, pathname, nd, flags, op, file, &opened); goto out; } |
669abf4e5 vfs: make path_op... |
3049 |
error = path_init(dfd, pathname->name, flags | LOOKUP_PARENT, nd, &base); |
31e6b01f4 fs: rcu-walk for ... |
3050 |
if (unlikely(error)) |
2675a4eb6 fs/namei.c: get d... |
3051 |
goto out; |
31e6b01f4 fs: rcu-walk for ... |
3052 |
|
fe2d35ff0 switch non-create... |
3053 |
current->total_link_count = 0; |
669abf4e5 vfs: make path_op... |
3054 |
error = link_path_walk(pathname->name, nd); |
31e6b01f4 fs: rcu-walk for ... |
3055 |
if (unlikely(error)) |
2675a4eb6 fs/namei.c: get d... |
3056 |
goto out; |
1da177e4c Linux-2.6.12-rc2 |
3057 |
|
2675a4eb6 fs/namei.c: get d... |
3058 3059 |
error = do_last(nd, &path, file, op, &opened, pathname); while (unlikely(error > 0)) { /* trailing symlink */ |
7b9337aaf fs: namei fix ->p... |
3060 |
struct path link = path; |
def4af30c Get rid of symlin... |
3061 |
void *cookie; |
574197e0d tidy the trailing... |
3062 |
if (!(nd->flags & LOOKUP_FOLLOW)) { |
73d049a40 open-style analog... |
3063 3064 |
path_put_conditional(&path, nd); path_put(&nd->path); |
2675a4eb6 fs/namei.c: get d... |
3065 |
error = -ELOOP; |
40b39136f path_openat: clea... |
3066 3067 |
break; } |
800179c9b fs: add link rest... |
3068 3069 3070 |
error = may_follow_link(&link, nd); if (unlikely(error)) break; |
73d049a40 open-style analog... |
3071 3072 |
nd->flags |= LOOKUP_PARENT; nd->flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL); |
574197e0d tidy the trailing... |
3073 |
error = follow_link(&link, nd, &cookie); |
c3e380b0b Collect "operatio... |
3074 |
if (unlikely(error)) |
2675a4eb6 fs/namei.c: get d... |
3075 3076 |
break; error = do_last(nd, &path, file, op, &opened, pathname); |
574197e0d tidy the trailing... |
3077 |
put_link(nd, &link, cookie); |
806b681cb Turn do_link spag... |
3078 |
} |
10fa8e62f Unify exits in O_... |
3079 |
out: |
73d049a40 open-style analog... |
3080 3081 |
if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) path_put(&nd->root); |
fe2d35ff0 switch non-create... |
3082 3083 |
if (base) fput(base); |
2675a4eb6 fs/namei.c: get d... |
3084 3085 |
if (!(opened & FILE_OPENED)) { BUG_ON(!error); |
30d904947 kill struct opendata |
3086 |
put_filp(file); |
16b1c1cd7 vfs: retry last c... |
3087 |
} |
2675a4eb6 fs/namei.c: get d... |
3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 |
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 |
3098 |
} |
669abf4e5 vfs: make path_op... |
3099 |
struct file *do_filp_open(int dfd, struct filename *pathname, |
f9652e10c allow build_open_... |
3100 |
const struct open_flags *op) |
13aab428a separate -ESTALE/... |
3101 |
{ |
73d049a40 open-style analog... |
3102 |
struct nameidata nd; |
f9652e10c allow build_open_... |
3103 |
int flags = op->lookup_flags; |
13aab428a separate -ESTALE/... |
3104 |
struct file *filp; |
73d049a40 open-style analog... |
3105 |
filp = path_openat(dfd, pathname, &nd, op, flags | LOOKUP_RCU); |
13aab428a separate -ESTALE/... |
3106 |
if (unlikely(filp == ERR_PTR(-ECHILD))) |
73d049a40 open-style analog... |
3107 |
filp = path_openat(dfd, pathname, &nd, op, flags); |
13aab428a separate -ESTALE/... |
3108 |
if (unlikely(filp == ERR_PTR(-ESTALE))) |
73d049a40 open-style analog... |
3109 |
filp = path_openat(dfd, pathname, &nd, op, flags | LOOKUP_REVAL); |
13aab428a separate -ESTALE/... |
3110 3111 |
return filp; } |
73d049a40 open-style analog... |
3112 |
struct file *do_file_open_root(struct dentry *dentry, struct vfsmount *mnt, |
f9652e10c allow build_open_... |
3113 |
const char *name, const struct open_flags *op) |
73d049a40 open-style analog... |
3114 3115 3116 |
{ struct nameidata nd; struct file *file; |
669abf4e5 vfs: make path_op... |
3117 |
struct filename filename = { .name = name }; |
f9652e10c allow build_open_... |
3118 |
int flags = op->lookup_flags | LOOKUP_ROOT; |
73d049a40 open-style analog... |
3119 3120 3121 |
nd.root.mnt = mnt; nd.root.dentry = dentry; |
b18825a7c VFS: Put a small ... |
3122 |
if (d_is_symlink(dentry) && op->intent & LOOKUP_OPEN) |
73d049a40 open-style analog... |
3123 |
return ERR_PTR(-ELOOP); |
669abf4e5 vfs: make path_op... |
3124 |
file = path_openat(-1, &filename, &nd, op, flags | LOOKUP_RCU); |
73d049a40 open-style analog... |
3125 |
if (unlikely(file == ERR_PTR(-ECHILD))) |
669abf4e5 vfs: make path_op... |
3126 |
file = path_openat(-1, &filename, &nd, op, flags); |
73d049a40 open-style analog... |
3127 |
if (unlikely(file == ERR_PTR(-ESTALE))) |
669abf4e5 vfs: make path_op... |
3128 |
file = path_openat(-1, &filename, &nd, op, flags | LOOKUP_REVAL); |
73d049a40 open-style analog... |
3129 3130 |
return file; } |
1ac12b4b6 vfs: turn is_dir ... |
3131 3132 |
struct dentry *kern_path_create(int dfd, const char *pathname, struct path *path, unsigned int lookup_flags) |
1da177e4c Linux-2.6.12-rc2 |
3133 |
{ |
c663e5d80 [PATCH] add some ... |
3134 |
struct dentry *dentry = ERR_PTR(-EEXIST); |
ed75e95de kill lookup_create() |
3135 |
struct nameidata nd; |
c30dabfe5 fs: Push mnt_want... |
3136 |
int err2; |
1ac12b4b6 vfs: turn is_dir ... |
3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 |
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() |
3147 3148 |
if (error) return ERR_PTR(error); |
1da177e4c Linux-2.6.12-rc2 |
3149 |
|
c663e5d80 [PATCH] add some ... |
3150 3151 3152 3153 |
/* * Yucky last component or no last component at all? * (foo/., foo/.., /////) */ |
ed75e95de kill lookup_create() |
3154 3155 3156 3157 |
if (nd.last_type != LAST_NORM) goto out; nd.flags &= ~LOOKUP_PARENT; nd.flags |= LOOKUP_CREATE | LOOKUP_EXCL; |
c663e5d80 [PATCH] add some ... |
3158 |
|
c30dabfe5 fs: Push mnt_want... |
3159 3160 |
/* 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 ... |
3161 3162 3163 |
/* * Do the final lookup. */ |
ed75e95de kill lookup_create() |
3164 3165 |
mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); dentry = lookup_hash(&nd); |
1da177e4c Linux-2.6.12-rc2 |
3166 |
if (IS_ERR(dentry)) |
a8104a9fc pull mnt_want_wri... |
3167 |
goto unlock; |
c663e5d80 [PATCH] add some ... |
3168 |
|
a8104a9fc pull mnt_want_wri... |
3169 |
error = -EEXIST; |
b18825a7c VFS: Put a small ... |
3170 |
if (d_is_positive(dentry)) |
a8104a9fc pull mnt_want_wri... |
3171 |
goto fail; |
b18825a7c VFS: Put a small ... |
3172 |
|
c663e5d80 [PATCH] add some ... |
3173 3174 3175 3176 3177 3178 |
/* * 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() |
3179 |
if (unlikely(!is_dir && nd.last.name[nd.last.len])) { |
a8104a9fc pull mnt_want_wri... |
3180 |
error = -ENOENT; |
ed75e95de kill lookup_create() |
3181 |
goto fail; |
e9baf6e59 [PATCH] return to... |
3182 |
} |
c30dabfe5 fs: Push mnt_want... |
3183 3184 |
if (unlikely(err2)) { error = err2; |
a8104a9fc pull mnt_want_wri... |
3185 |
goto fail; |
c30dabfe5 fs: Push mnt_want... |
3186 |
} |
ed75e95de kill lookup_create() |
3187 |
*path = nd.path; |
1da177e4c Linux-2.6.12-rc2 |
3188 |
return dentry; |
1da177e4c Linux-2.6.12-rc2 |
3189 |
fail: |
a8104a9fc pull mnt_want_wri... |
3190 3191 3192 |
dput(dentry); dentry = ERR_PTR(error); unlock: |
ed75e95de kill lookup_create() |
3193 |
mutex_unlock(&nd.path.dentry->d_inode->i_mutex); |
c30dabfe5 fs: Push mnt_want... |
3194 3195 |
if (!err2) mnt_drop_write(nd.path.mnt); |
ed75e95de kill lookup_create() |
3196 3197 |
out: path_put(&nd.path); |
1da177e4c Linux-2.6.12-rc2 |
3198 3199 |
return dentry; } |
dae6ad8f3 new helpers: kern... |
3200 |
EXPORT_SYMBOL(kern_path_create); |
921a1650d new helper: done_... |
3201 3202 3203 3204 |
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... |
3205 |
mnt_drop_write(path->mnt); |
921a1650d new helper: done_... |
3206 3207 3208 |
path_put(path); } EXPORT_SYMBOL(done_path_create); |
1ac12b4b6 vfs: turn is_dir ... |
3209 3210 |
struct dentry *user_path_create(int dfd, const char __user *pathname, struct path *path, unsigned int lookup_flags) |
dae6ad8f3 new helpers: kern... |
3211 |
{ |
91a27b2a7 vfs: define struc... |
3212 |
struct filename *tmp = getname(pathname); |
dae6ad8f3 new helpers: kern... |
3213 3214 3215 |
struct dentry *res; if (IS_ERR(tmp)) return ERR_CAST(tmp); |
1ac12b4b6 vfs: turn is_dir ... |
3216 |
res = kern_path_create(dfd, tmp->name, path, lookup_flags); |
dae6ad8f3 new helpers: kern... |
3217 3218 3219 3220 |
putname(tmp); return res; } EXPORT_SYMBOL(user_path_create); |
1a67aafb5 switch ->mknod() ... |
3221 |
int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4c Linux-2.6.12-rc2 |
3222 |
{ |
a95164d97 [patch 3/4] vfs: ... |
3223 |
int error = may_create(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
3224 3225 3226 |
if (error) return error; |
975d6b393 vfs: Don't allow ... |
3227 |
if ((S_ISCHR(mode) || S_ISBLK(mode)) && !capable(CAP_MKNOD)) |
1da177e4c Linux-2.6.12-rc2 |
3228 |
return -EPERM; |
acfa4380e inode->i_op is ne... |
3229 |
if (!dir->i_op->mknod) |
1da177e4c Linux-2.6.12-rc2 |
3230 |
return -EPERM; |
08ce5f16e cgroups: implemen... |
3231 3232 3233 |
error = devcgroup_inode_mknod(mode, dev); if (error) return error; |
1da177e4c Linux-2.6.12-rc2 |
3234 3235 3236 |
error = security_inode_mknod(dir, dentry, mode, dev); if (error) return error; |
1da177e4c Linux-2.6.12-rc2 |
3237 |
error = dir->i_op->mknod(dir, dentry, mode, dev); |
a74574aaf [PATCH] Remove se... |
3238 |
if (!error) |
f38aa9422 [PATCH] Pass dent... |
3239 |
fsnotify_create(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
3240 3241 |
return error; } |
4d3595073 namei.c: move EXP... |
3242 |
EXPORT_SYMBOL(vfs_mknod); |
1da177e4c Linux-2.6.12-rc2 |
3243 |
|
f69aac000 switch may_mknod(... |
3244 |
static int may_mknod(umode_t mode) |
463c31972 [PATCH] r/o bind ... |
3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 |
{ 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... |
3260 |
SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode, |
2e4d0924e [CVE-2009-0029] S... |
3261 |
unsigned, dev) |
1da177e4c Linux-2.6.12-rc2 |
3262 |
{ |
2ad94ae65 [PATCH] new (loca... |
3263 |
struct dentry *dentry; |
dae6ad8f3 new helpers: kern... |
3264 3265 |
struct path path; int error; |
972567f14 vfs: fix mknodat ... |
3266 |
unsigned int lookup_flags = 0; |
1da177e4c Linux-2.6.12-rc2 |
3267 |
|
8e4bfca1d mknod: take sanit... |
3268 3269 3270 |
error = may_mknod(mode); if (error) return error; |
972567f14 vfs: fix mknodat ... |
3271 3272 |
retry: dentry = user_path_create(dfd, filename, &path, lookup_flags); |
dae6ad8f3 new helpers: kern... |
3273 3274 |
if (IS_ERR(dentry)) return PTR_ERR(dentry); |
2ad94ae65 [PATCH] new (loca... |
3275 |
|
dae6ad8f3 new helpers: kern... |
3276 |
if (!IS_POSIXACL(path.dentry->d_inode)) |
ce3b0f8d5 New helper - curr... |
3277 |
mode &= ~current_umask(); |
dae6ad8f3 new helpers: kern... |
3278 |
error = security_path_mknod(&path, dentry, mode, dev); |
be6d3e56a introduce new LSM... |
3279 |
if (error) |
a8104a9fc pull mnt_want_wri... |
3280 |
goto out; |
463c31972 [PATCH] r/o bind ... |
3281 |
switch (mode & S_IFMT) { |
1da177e4c Linux-2.6.12-rc2 |
3282 |
case 0: case S_IFREG: |
312b63fba don't pass nameid... |
3283 |
error = vfs_create(path.dentry->d_inode,dentry,mode,true); |
1da177e4c Linux-2.6.12-rc2 |
3284 3285 |
break; case S_IFCHR: case S_IFBLK: |
dae6ad8f3 new helpers: kern... |
3286 |
error = vfs_mknod(path.dentry->d_inode,dentry,mode, |
1da177e4c Linux-2.6.12-rc2 |
3287 3288 3289 |
new_decode_dev(dev)); break; case S_IFIFO: case S_IFSOCK: |
dae6ad8f3 new helpers: kern... |
3290 |
error = vfs_mknod(path.dentry->d_inode,dentry,mode,0); |
1da177e4c Linux-2.6.12-rc2 |
3291 |
break; |
1da177e4c Linux-2.6.12-rc2 |
3292 |
} |
a8104a9fc pull mnt_want_wri... |
3293 |
out: |
921a1650d new helper: done_... |
3294 |
done_path_create(&path, dentry); |
972567f14 vfs: fix mknodat ... |
3295 3296 3297 3298 |
if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } |
1da177e4c Linux-2.6.12-rc2 |
3299 3300 |
return error; } |
8208a22bb switch sys_mknoda... |
3301 |
SYSCALL_DEFINE3(mknod, const char __user *, filename, umode_t, mode, unsigned, dev) |
5590ff0d5 [PATCH] vfs: *at ... |
3302 3303 3304 |
{ return sys_mknodat(AT_FDCWD, filename, mode, dev); } |
18bb1db3e switch vfs_mkdir(... |
3305 |
int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4c Linux-2.6.12-rc2 |
3306 |
{ |
a95164d97 [patch 3/4] vfs: ... |
3307 |
int error = may_create(dir, dentry); |
8de527787 vfs: check i_nlin... |
3308 |
unsigned max_links = dir->i_sb->s_max_links; |
1da177e4c Linux-2.6.12-rc2 |
3309 3310 3311 |
if (error) return error; |
acfa4380e inode->i_op is ne... |
3312 |
if (!dir->i_op->mkdir) |
1da177e4c Linux-2.6.12-rc2 |
3313 3314 3315 3316 3317 3318 |
return -EPERM; mode &= (S_IRWXUGO|S_ISVTX); error = security_inode_mkdir(dir, dentry, mode); if (error) return error; |
8de527787 vfs: check i_nlin... |
3319 3320 |
if (max_links && dir->i_nlink >= max_links) return -EMLINK; |
1da177e4c Linux-2.6.12-rc2 |
3321 |
error = dir->i_op->mkdir(dir, dentry, mode); |
a74574aaf [PATCH] Remove se... |
3322 |
if (!error) |
f38aa9422 [PATCH] Pass dent... |
3323 |
fsnotify_mkdir(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
3324 3325 |
return error; } |
4d3595073 namei.c: move EXP... |
3326 |
EXPORT_SYMBOL(vfs_mkdir); |
1da177e4c Linux-2.6.12-rc2 |
3327 |
|
a218d0fdc switch open and m... |
3328 |
SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode) |
1da177e4c Linux-2.6.12-rc2 |
3329 |
{ |
6902d925d [PATCH] r/o bind ... |
3330 |
struct dentry *dentry; |
dae6ad8f3 new helpers: kern... |
3331 3332 |
struct path path; int error; |
b76d8b822 vfs: fix mkdirat ... |
3333 |
unsigned int lookup_flags = LOOKUP_DIRECTORY; |
1da177e4c Linux-2.6.12-rc2 |
3334 |
|
b76d8b822 vfs: fix mkdirat ... |
3335 3336 |
retry: dentry = user_path_create(dfd, pathname, &path, lookup_flags); |
6902d925d [PATCH] r/o bind ... |
3337 |
if (IS_ERR(dentry)) |
dae6ad8f3 new helpers: kern... |
3338 |
return PTR_ERR(dentry); |
1da177e4c Linux-2.6.12-rc2 |
3339 |
|
dae6ad8f3 new helpers: kern... |
3340 |
if (!IS_POSIXACL(path.dentry->d_inode)) |
ce3b0f8d5 New helper - curr... |
3341 |
mode &= ~current_umask(); |
dae6ad8f3 new helpers: kern... |
3342 |
error = security_path_mkdir(&path, dentry, mode); |
a8104a9fc pull mnt_want_wri... |
3343 3344 |
if (!error) error = vfs_mkdir(path.dentry->d_inode, dentry, mode); |
921a1650d new helper: done_... |
3345 |
done_path_create(&path, dentry); |
b76d8b822 vfs: fix mkdirat ... |
3346 3347 3348 3349 |
if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } |
1da177e4c Linux-2.6.12-rc2 |
3350 3351 |
return error; } |
a218d0fdc switch open and m... |
3352 |
SYSCALL_DEFINE2(mkdir, const char __user *, pathname, umode_t, mode) |
5590ff0d5 [PATCH] vfs: *at ... |
3353 3354 3355 |
{ return sys_mkdirat(AT_FDCWD, pathname, mode); } |
1da177e4c Linux-2.6.12-rc2 |
3356 |
/* |
a71905f0d vfs: update dentr... |
3357 |
* The dentry_unhash() helper will try to drop the dentry early: we |
c0d025948 vfs: fix out-of-d... |
3358 |
* should have a usage count of 1 if we're the only user of this |
a71905f0d vfs: update dentr... |
3359 3360 |
* dentry, and if that is true (possibly after pruning the dcache), * then we drop the dentry now. |
1da177e4c Linux-2.6.12-rc2 |
3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 |
* * 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... |
3373 |
shrink_dcache_parent(dentry); |
1da177e4c Linux-2.6.12-rc2 |
3374 |
spin_lock(&dentry->d_lock); |
98474236f vfs: make the den... |
3375 |
if (dentry->d_lockref.count == 1) |
1da177e4c Linux-2.6.12-rc2 |
3376 3377 |
__d_drop(dentry); spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
3378 |
} |
4d3595073 namei.c: move EXP... |
3379 |
EXPORT_SYMBOL(dentry_unhash); |
1da177e4c Linux-2.6.12-rc2 |
3380 3381 3382 3383 3384 3385 3386 |
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... |
3387 |
if (!dir->i_op->rmdir) |
1da177e4c Linux-2.6.12-rc2 |
3388 |
return -EPERM; |
1d2ef5901 restore pinning t... |
3389 |
dget(dentry); |
1b1dcc1b5 [PATCH] mutex sub... |
3390 |
mutex_lock(&dentry->d_inode->i_mutex); |
912dbc15d vfs: clean up vfs... |
3391 3392 |
error = -EBUSY; |
1da177e4c Linux-2.6.12-rc2 |
3393 |
if (d_mountpoint(dentry)) |
912dbc15d vfs: clean up vfs... |
3394 3395 3396 3397 3398 |
goto out; error = security_inode_rmdir(dir, dentry); if (error) goto out; |
3cebde241 vfs: shrink_dcach... |
3399 |
shrink_dcache_parent(dentry); |
912dbc15d vfs: clean up vfs... |
3400 3401 3402 3403 3404 3405 3406 3407 |
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... |
3408 |
mutex_unlock(&dentry->d_inode->i_mutex); |
1d2ef5901 restore pinning t... |
3409 |
dput(dentry); |
912dbc15d vfs: clean up vfs... |
3410 |
if (!error) |
1da177e4c Linux-2.6.12-rc2 |
3411 |
d_delete(dentry); |
1da177e4c Linux-2.6.12-rc2 |
3412 3413 |
return error; } |
4d3595073 namei.c: move EXP... |
3414 |
EXPORT_SYMBOL(vfs_rmdir); |
1da177e4c Linux-2.6.12-rc2 |
3415 |
|
5590ff0d5 [PATCH] vfs: *at ... |
3416 |
static long do_rmdir(int dfd, const char __user *pathname) |
1da177e4c Linux-2.6.12-rc2 |
3417 3418 |
{ int error = 0; |
91a27b2a7 vfs: define struc... |
3419 |
struct filename *name; |
1da177e4c Linux-2.6.12-rc2 |
3420 3421 |
struct dentry *dentry; struct nameidata nd; |
c6ee92069 vfs: make do_rmdi... |
3422 3423 3424 |
unsigned int lookup_flags = 0; retry: name = user_path_parent(dfd, pathname, &nd, lookup_flags); |
91a27b2a7 vfs: define struc... |
3425 3426 |
if (IS_ERR(name)) return PTR_ERR(name); |
1da177e4c Linux-2.6.12-rc2 |
3427 3428 |
switch(nd.last_type) { |
0612d9fb2 [PATCH vfs-2.6 5/... |
3429 3430 3431 3432 3433 3434 3435 3436 3437 |
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 |
3438 |
} |
0612d9fb2 [PATCH vfs-2.6 5/... |
3439 3440 |
nd.flags &= ~LOOKUP_PARENT; |
c30dabfe5 fs: Push mnt_want... |
3441 3442 3443 |
error = mnt_want_write(nd.path.mnt); if (error) goto exit1; |
0612d9fb2 [PATCH vfs-2.6 5/... |
3444 |
|
4ac913785 Embed a struct pa... |
3445 |
mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); |
49705b774 [PATCH] sanitize ... |
3446 |
dentry = lookup_hash(&nd); |
1da177e4c Linux-2.6.12-rc2 |
3447 |
error = PTR_ERR(dentry); |
6902d925d [PATCH] r/o bind ... |
3448 3449 |
if (IS_ERR(dentry)) goto exit2; |
e6bc45d65 vfs: make unlink(... |
3450 3451 3452 3453 |
if (!dentry->d_inode) { error = -ENOENT; goto exit3; } |
be6d3e56a introduce new LSM... |
3454 3455 |
error = security_path_rmdir(&nd.path, dentry); if (error) |
c30dabfe5 fs: Push mnt_want... |
3456 |
goto exit3; |
4ac913785 Embed a struct pa... |
3457 |
error = vfs_rmdir(nd.path.dentry->d_inode, dentry); |
0622753b8 [PATCH] r/o bind ... |
3458 |
exit3: |
6902d925d [PATCH] r/o bind ... |
3459 3460 |
dput(dentry); exit2: |
4ac913785 Embed a struct pa... |
3461 |
mutex_unlock(&nd.path.dentry->d_inode->i_mutex); |
c30dabfe5 fs: Push mnt_want... |
3462 |
mnt_drop_write(nd.path.mnt); |
1da177e4c Linux-2.6.12-rc2 |
3463 |
exit1: |
1d957f9bf Introduce path_put() |
3464 |
path_put(&nd.path); |
1da177e4c Linux-2.6.12-rc2 |
3465 |
putname(name); |
c6ee92069 vfs: make do_rmdi... |
3466 3467 3468 3469 |
if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } |
1da177e4c Linux-2.6.12-rc2 |
3470 3471 |
return error; } |
3cdad4288 [CVE-2009-0029] S... |
3472 |
SYSCALL_DEFINE1(rmdir, const char __user *, pathname) |
5590ff0d5 [PATCH] vfs: *at ... |
3473 3474 3475 |
{ return do_rmdir(AT_FDCWD, pathname); } |
b21996e36 locks: break dele... |
3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 |
/** * 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 |
3495 |
{ |
9accbb977 namei: minor vfs_... |
3496 |
struct inode *target = dentry->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
3497 3498 3499 3500 |
int error = may_delete(dir, dentry, 0); if (error) return error; |
acfa4380e inode->i_op is ne... |
3501 |
if (!dir->i_op->unlink) |
1da177e4c Linux-2.6.12-rc2 |
3502 |
return -EPERM; |
9accbb977 namei: minor vfs_... |
3503 |
mutex_lock(&target->i_mutex); |
1da177e4c Linux-2.6.12-rc2 |
3504 3505 3506 3507 |
if (d_mountpoint(dentry)) error = -EBUSY; else { error = security_inode_unlink(dir, dentry); |
bec1052e5 set S_DEAD on unl... |
3508 |
if (!error) { |
5a14696c1 locks: helper fun... |
3509 3510 |
error = try_break_deleg(target, delegated_inode); if (error) |
b21996e36 locks: break dele... |
3511 |
goto out; |
1da177e4c Linux-2.6.12-rc2 |
3512 |
error = dir->i_op->unlink(dir, dentry); |
bec1052e5 set S_DEAD on unl... |
3513 |
if (!error) |
d83c49f3e Fix the regressio... |
3514 |
dont_mount(dentry); |
bec1052e5 set S_DEAD on unl... |
3515 |
} |
1da177e4c Linux-2.6.12-rc2 |
3516 |
} |
b21996e36 locks: break dele... |
3517 |
out: |
9accbb977 namei: minor vfs_... |
3518 |
mutex_unlock(&target->i_mutex); |
1da177e4c Linux-2.6.12-rc2 |
3519 3520 3521 |
/* We don't d_delete() NFS sillyrenamed files--they still exist. */ if (!error && !(dentry->d_flags & DCACHE_NFSFS_RENAMED)) { |
9accbb977 namei: minor vfs_... |
3522 |
fsnotify_link_count(target); |
e234f35c5 [PATCH] inotify d... |
3523 |
d_delete(dentry); |
1da177e4c Linux-2.6.12-rc2 |
3524 |
} |
0eeca2830 [PATCH] inotify |
3525 |
|
1da177e4c Linux-2.6.12-rc2 |
3526 3527 |
return error; } |
4d3595073 namei.c: move EXP... |
3528 |
EXPORT_SYMBOL(vfs_unlink); |
1da177e4c Linux-2.6.12-rc2 |
3529 3530 3531 |
/* * Make sure that the actual truncation of the file will occur outside its |
1b1dcc1b5 [PATCH] mutex sub... |
3532 |
* directory's i_mutex. Truncate can take a long time if there is a lot of |
1da177e4c Linux-2.6.12-rc2 |
3533 3534 3535 |
* writeout happening, and we don't want to prevent access to the directory * while waiting on the I/O. */ |
5590ff0d5 [PATCH] vfs: *at ... |
3536 |
static long do_unlinkat(int dfd, const char __user *pathname) |
1da177e4c Linux-2.6.12-rc2 |
3537 |
{ |
2ad94ae65 [PATCH] new (loca... |
3538 |
int error; |
91a27b2a7 vfs: define struc... |
3539 |
struct filename *name; |
1da177e4c Linux-2.6.12-rc2 |
3540 3541 3542 |
struct dentry *dentry; struct nameidata nd; struct inode *inode = NULL; |
b21996e36 locks: break dele... |
3543 |
struct inode *delegated_inode = NULL; |
5d18f8133 vfs: make do_unli... |
3544 3545 3546 |
unsigned int lookup_flags = 0; retry: name = user_path_parent(dfd, pathname, &nd, lookup_flags); |
91a27b2a7 vfs: define struc... |
3547 3548 |
if (IS_ERR(name)) return PTR_ERR(name); |
2ad94ae65 [PATCH] new (loca... |
3549 |
|
1da177e4c Linux-2.6.12-rc2 |
3550 3551 3552 |
error = -EISDIR; if (nd.last_type != LAST_NORM) goto exit1; |
0612d9fb2 [PATCH vfs-2.6 5/... |
3553 3554 |
nd.flags &= ~LOOKUP_PARENT; |
c30dabfe5 fs: Push mnt_want... |
3555 3556 3557 |
error = mnt_want_write(nd.path.mnt); if (error) goto exit1; |
b21996e36 locks: break dele... |
3558 |
retry_deleg: |
4ac913785 Embed a struct pa... |
3559 |
mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); |
49705b774 [PATCH] sanitize ... |
3560 |
dentry = lookup_hash(&nd); |
1da177e4c Linux-2.6.12-rc2 |
3561 3562 3563 |
error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { /* Why not before? Because we want correct error value */ |
50338b889 fix wrong iput on... |
3564 3565 |
if (nd.last.name[nd.last.len]) goto slashes; |
1da177e4c Linux-2.6.12-rc2 |
3566 |
inode = dentry->d_inode; |
b18825a7c VFS: Put a small ... |
3567 |
if (d_is_negative(dentry)) |
e6bc45d65 vfs: make unlink(... |
3568 3569 |
goto slashes; ihold(inode); |
be6d3e56a introduce new LSM... |
3570 3571 |
error = security_path_unlink(&nd.path, dentry); if (error) |
c30dabfe5 fs: Push mnt_want... |
3572 |
goto exit2; |
b21996e36 locks: break dele... |
3573 |
error = vfs_unlink(nd.path.dentry->d_inode, dentry, &delegated_inode); |
c30dabfe5 fs: Push mnt_want... |
3574 |
exit2: |
1da177e4c Linux-2.6.12-rc2 |
3575 3576 |
dput(dentry); } |
4ac913785 Embed a struct pa... |
3577 |
mutex_unlock(&nd.path.dentry->d_inode->i_mutex); |
1da177e4c Linux-2.6.12-rc2 |
3578 3579 |
if (inode) iput(inode); /* truncate the inode here */ |
b21996e36 locks: break dele... |
3580 3581 |
inode = NULL; if (delegated_inode) { |
5a14696c1 locks: helper fun... |
3582 |
error = break_deleg_wait(&delegated_inode); |
b21996e36 locks: break dele... |
3583 3584 3585 |
if (!error) goto retry_deleg; } |
c30dabfe5 fs: Push mnt_want... |
3586 |
mnt_drop_write(nd.path.mnt); |
1da177e4c Linux-2.6.12-rc2 |
3587 |
exit1: |
1d957f9bf Introduce path_put() |
3588 |
path_put(&nd.path); |
1da177e4c Linux-2.6.12-rc2 |
3589 |
putname(name); |
5d18f8133 vfs: make do_unli... |
3590 3591 3592 3593 3594 |
if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; inode = NULL; goto retry; } |
1da177e4c Linux-2.6.12-rc2 |
3595 3596 3597 |
return error; slashes: |
b18825a7c VFS: Put a small ... |
3598 3599 |
if (d_is_negative(dentry)) error = -ENOENT; |
44b1d5304 vfs: add d_is_dir() |
3600 |
else if (d_is_dir(dentry)) |
b18825a7c VFS: Put a small ... |
3601 3602 3603 |
error = -EISDIR; else error = -ENOTDIR; |
1da177e4c Linux-2.6.12-rc2 |
3604 3605 |
goto exit2; } |
2e4d0924e [CVE-2009-0029] S... |
3606 |
SYSCALL_DEFINE3(unlinkat, int, dfd, const char __user *, pathname, int, flag) |
5590ff0d5 [PATCH] vfs: *at ... |
3607 3608 3609 3610 3611 3612 3613 3614 3615 |
{ 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... |
3616 |
SYSCALL_DEFINE1(unlink, const char __user *, pathname) |
5590ff0d5 [PATCH] vfs: *at ... |
3617 3618 3619 |
{ return do_unlinkat(AT_FDCWD, pathname); } |
db2e747b1 [patch 5/5] vfs: ... |
3620 |
int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname) |
1da177e4c Linux-2.6.12-rc2 |
3621 |
{ |
a95164d97 [patch 3/4] vfs: ... |
3622 |
int error = may_create(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
3623 3624 3625 |
if (error) return error; |
acfa4380e inode->i_op is ne... |
3626 |
if (!dir->i_op->symlink) |
1da177e4c Linux-2.6.12-rc2 |
3627 3628 3629 3630 3631 |
return -EPERM; error = security_inode_symlink(dir, dentry, oldname); if (error) return error; |
1da177e4c Linux-2.6.12-rc2 |
3632 |
error = dir->i_op->symlink(dir, dentry, oldname); |
a74574aaf [PATCH] Remove se... |
3633 |
if (!error) |
f38aa9422 [PATCH] Pass dent... |
3634 |
fsnotify_create(dir, dentry); |
1da177e4c Linux-2.6.12-rc2 |
3635 3636 |
return error; } |
4d3595073 namei.c: move EXP... |
3637 |
EXPORT_SYMBOL(vfs_symlink); |
1da177e4c Linux-2.6.12-rc2 |
3638 |
|
2e4d0924e [CVE-2009-0029] S... |
3639 3640 |
SYSCALL_DEFINE3(symlinkat, const char __user *, oldname, int, newdfd, const char __user *, newname) |
1da177e4c Linux-2.6.12-rc2 |
3641 |
{ |
2ad94ae65 [PATCH] new (loca... |
3642 |
int error; |
91a27b2a7 vfs: define struc... |
3643 |
struct filename *from; |
6902d925d [PATCH] r/o bind ... |
3644 |
struct dentry *dentry; |
dae6ad8f3 new helpers: kern... |
3645 |
struct path path; |
f46d3567b vfs: fix symlinka... |
3646 |
unsigned int lookup_flags = 0; |
1da177e4c Linux-2.6.12-rc2 |
3647 3648 |
from = getname(oldname); |
2ad94ae65 [PATCH] new (loca... |
3649 |
if (IS_ERR(from)) |
1da177e4c Linux-2.6.12-rc2 |
3650 |
return PTR_ERR(from); |
f46d3567b vfs: fix symlinka... |
3651 3652 |
retry: dentry = user_path_create(newdfd, newname, &path, lookup_flags); |
6902d925d [PATCH] r/o bind ... |
3653 3654 |
error = PTR_ERR(dentry); if (IS_ERR(dentry)) |
dae6ad8f3 new helpers: kern... |
3655 |
goto out_putname; |
6902d925d [PATCH] r/o bind ... |
3656 |
|
91a27b2a7 vfs: define struc... |
3657 |
error = security_path_symlink(&path, dentry, from->name); |
a8104a9fc pull mnt_want_wri... |
3658 |
if (!error) |
91a27b2a7 vfs: define struc... |
3659 |
error = vfs_symlink(path.dentry->d_inode, dentry, from->name); |
921a1650d new helper: done_... |
3660 |
done_path_create(&path, dentry); |
f46d3567b vfs: fix symlinka... |
3661 3662 3663 3664 |
if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } |
6902d925d [PATCH] r/o bind ... |
3665 |
out_putname: |
1da177e4c Linux-2.6.12-rc2 |
3666 3667 3668 |
putname(from); return error; } |
3480b2574 [CVE-2009-0029] S... |
3669 |
SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newname) |
5590ff0d5 [PATCH] vfs: *at ... |
3670 3671 3672 |
{ return sys_symlinkat(oldname, AT_FDCWD, newname); } |
146a8595c locks: break dele... |
3673 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 |
/** * 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 |
3693 3694 |
{ struct inode *inode = old_dentry->d_inode; |
8de527787 vfs: check i_nlin... |
3695 |
unsigned max_links = dir->i_sb->s_max_links; |
1da177e4c Linux-2.6.12-rc2 |
3696 3697 3698 3699 |
int error; if (!inode) return -ENOENT; |
a95164d97 [patch 3/4] vfs: ... |
3700 |
error = may_create(dir, new_dentry); |
1da177e4c Linux-2.6.12-rc2 |
3701 3702 3703 3704 3705 3706 3707 3708 3709 3710 3711 |
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... |
3712 |
if (!dir->i_op->link) |
1da177e4c Linux-2.6.12-rc2 |
3713 |
return -EPERM; |
7e79eedb3 [patch 4/5] vfs: ... |
3714 |
if (S_ISDIR(inode->i_mode)) |
1da177e4c Linux-2.6.12-rc2 |
3715 3716 3717 3718 3719 |
return -EPERM; error = security_inode_link(old_dentry, dir, new_dentry); if (error) return error; |
7e79eedb3 [patch 4/5] vfs: ... |
3720 |
mutex_lock(&inode->i_mutex); |
aae8a97d3 fs: Don't allow t... |
3721 |
/* Make sure we don't allow creating hardlink to an unlinked file */ |
f4e0c30c1 allow the temp fi... |
3722 |
if (inode->i_nlink == 0 && !(inode->i_state & I_LINKABLE)) |
aae8a97d3 fs: Don't allow t... |
3723 |
error = -ENOENT; |
8de527787 vfs: check i_nlin... |
3724 3725 |
else if (max_links && inode->i_nlink >= max_links) error = -EMLINK; |
146a8595c locks: break dele... |
3726 3727 3728 3729 3730 |
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... |
3731 3732 3733 3734 3735 3736 |
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: ... |
3737 |
mutex_unlock(&inode->i_mutex); |
e31e14ec3 [PATCH] remove th... |
3738 |
if (!error) |
7e79eedb3 [patch 4/5] vfs: ... |
3739 |
fsnotify_link(dir, inode, new_dentry); |
1da177e4c Linux-2.6.12-rc2 |
3740 3741 |
return error; } |
4d3595073 namei.c: move EXP... |
3742 |
EXPORT_SYMBOL(vfs_link); |
1da177e4c Linux-2.6.12-rc2 |
3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 |
/* * 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... |
3753 3754 |
SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname, int, newdfd, const char __user *, newname, int, flags) |
1da177e4c Linux-2.6.12-rc2 |
3755 3756 |
{ struct dentry *new_dentry; |
dae6ad8f3 new helpers: kern... |
3757 |
struct path old_path, new_path; |
146a8595c locks: break dele... |
3758 |
struct inode *delegated_inode = NULL; |
11a7b371b fs: allow AT_EMPT... |
3759 |
int how = 0; |
1da177e4c Linux-2.6.12-rc2 |
3760 |
int error; |
1da177e4c Linux-2.6.12-rc2 |
3761 |
|
11a7b371b fs: allow AT_EMPT... |
3762 |
if ((flags & ~(AT_SYMLINK_FOLLOW | AT_EMPTY_PATH)) != 0) |
c04030e16 [PATCH] flags par... |
3763 |
return -EINVAL; |
11a7b371b fs: allow AT_EMPT... |
3764 |
/* |
f0cc6ffb8 Revert "fs: Allow... |
3765 3766 3767 |
* 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... |
3768 |
*/ |
f0cc6ffb8 Revert "fs: Allow... |
3769 3770 3771 |
if (flags & AT_EMPTY_PATH) { if (!capable(CAP_DAC_READ_SEARCH)) return -ENOENT; |
11a7b371b fs: allow AT_EMPT... |
3772 |
how = LOOKUP_EMPTY; |
f0cc6ffb8 Revert "fs: Allow... |
3773 |
} |
11a7b371b fs: allow AT_EMPT... |
3774 3775 3776 |
if (flags & AT_SYMLINK_FOLLOW) how |= LOOKUP_FOLLOW; |
442e31ca5 vfs: fix linkat t... |
3777 |
retry: |
11a7b371b fs: allow AT_EMPT... |
3778 |
error = user_path_at(olddfd, oldname, how, &old_path); |
1da177e4c Linux-2.6.12-rc2 |
3779 |
if (error) |
2ad94ae65 [PATCH] new (loca... |
3780 |
return error; |
442e31ca5 vfs: fix linkat t... |
3781 3782 |
new_dentry = user_path_create(newdfd, newname, &new_path, (how & LOOKUP_REVAL)); |
1da177e4c Linux-2.6.12-rc2 |
3783 |
error = PTR_ERR(new_dentry); |
6902d925d [PATCH] r/o bind ... |
3784 |
if (IS_ERR(new_dentry)) |
dae6ad8f3 new helpers: kern... |
3785 3786 3787 3788 3789 |
goto out; error = -EXDEV; if (old_path.mnt != new_path.mnt) goto out_dput; |
800179c9b fs: add link rest... |
3790 3791 3792 |
error = may_linkat(&old_path); if (unlikely(error)) goto out_dput; |
dae6ad8f3 new helpers: kern... |
3793 |
error = security_path_link(old_path.dentry, &new_path, new_dentry); |
be6d3e56a introduce new LSM... |
3794 |
if (error) |
a8104a9fc pull mnt_want_wri... |
3795 |
goto out_dput; |
146a8595c locks: break dele... |
3796 |
error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry, &delegated_inode); |
75c3f29de [PATCH] r/o bind ... |
3797 |
out_dput: |
921a1650d new helper: done_... |
3798 |
done_path_create(&new_path, new_dentry); |
146a8595c locks: break dele... |
3799 3800 |
if (delegated_inode) { error = break_deleg_wait(&delegated_inode); |
d22e6338d Fix mountpoint re... |
3801 3802 |
if (!error) { path_put(&old_path); |
146a8595c locks: break dele... |
3803 |
goto retry; |
d22e6338d Fix mountpoint re... |
3804 |
} |
146a8595c locks: break dele... |
3805 |
} |
442e31ca5 vfs: fix linkat t... |
3806 |
if (retry_estale(error, how)) { |
d22e6338d Fix mountpoint re... |
3807 |
path_put(&old_path); |
442e31ca5 vfs: fix linkat t... |
3808 3809 3810 |
how |= LOOKUP_REVAL; goto retry; } |
1da177e4c Linux-2.6.12-rc2 |
3811 |
out: |
2d8f30380 [PATCH] sanitize ... |
3812 |
path_put(&old_path); |
1da177e4c Linux-2.6.12-rc2 |
3813 3814 3815 |
return error; } |
3480b2574 [CVE-2009-0029] S... |
3816 |
SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname) |
5590ff0d5 [PATCH] vfs: *at ... |
3817 |
{ |
c04030e16 [PATCH] flags par... |
3818 |
return sys_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0); |
5590ff0d5 [PATCH] vfs: *at ... |
3819 |
} |
bc27027a7 vfs: rename: use ... |
3820 3821 3822 3823 3824 3825 3826 |
/** * 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... |
3827 |
* @flags: rename flags |
bc27027a7 vfs: rename: use ... |
3828 3829 3830 3831 3832 3833 3834 3835 3836 3837 3838 3839 3840 3841 |
* * 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 |
3842 3843 3844 3845 3846 3847 |
* 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: * a) we can get into loop creation. Check is done in is_subdir(). * 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... |
3848 |
* sb->s_vfs_rename_mutex. We might be more accurate, but that's another |
1da177e4c Linux-2.6.12-rc2 |
3849 |
* story. |
6cedba896 vfs: take i_mutex... |
3850 3851 |
* 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... |
3852 |
* And that - after we got ->i_mutex on parents (until then we don't know |
1da177e4c Linux-2.6.12-rc2 |
3853 3854 |
* 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... |
3855 |
* only under ->s_vfs_rename_mutex _and_ that parent of the object we |
1da177e4c Linux-2.6.12-rc2 |
3856 3857 3858 |
* 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... |
3859 |
* lock child" and rename is under ->s_vfs_rename_mutex. |
1da177e4c Linux-2.6.12-rc2 |
3860 3861 3862 |
* 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_... |
3863 |
* d) conversion from fhandle to dentry may come in the wrong moment - when |
1b1dcc1b5 [PATCH] mutex sub... |
3864 |
* we are removing the target. Solution: we will have to grab ->i_mutex |
1da177e4c Linux-2.6.12-rc2 |
3865 |
* in the fhandle_to_dentry code. [FIXME - current nfsfh.c relies on |
c41b20e72 Fix misspellings ... |
3866 |
* ->i_mutex on parents, which works but leads to some truly excessive |
1da177e4c Linux-2.6.12-rc2 |
3867 3868 |
* locking]. */ |
bc27027a7 vfs: rename: use ... |
3869 3870 |
int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, |
520c8b165 vfs: add renameat... |
3871 |
struct inode **delegated_inode, unsigned int flags) |
1da177e4c Linux-2.6.12-rc2 |
3872 |
{ |
bc27027a7 vfs: rename: use ... |
3873 3874 3875 3876 |
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... |
3877 |
struct inode *target = new_dentry->d_inode; |
da1ce0670 vfs: add cross-re... |
3878 3879 |
bool new_is_dir = false; unsigned max_links = new_dir->i_sb->s_max_links; |
bc27027a7 vfs: rename: use ... |
3880 3881 3882 3883 3884 3885 3886 |
if (source == target) return 0; error = may_delete(old_dir, old_dentry, is_dir); if (error) return error; |
da1ce0670 vfs: add cross-re... |
3887 |
if (!target) { |
bc27027a7 vfs: rename: use ... |
3888 |
error = may_create(new_dir, new_dentry); |
da1ce0670 vfs: add cross-re... |
3889 3890 3891 3892 3893 3894 3895 3896 |
} 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 ... |
3897 3898 3899 3900 3901 |
if (error) return error; if (!old_dir->i_op->rename) return -EPERM; |
1da177e4c Linux-2.6.12-rc2 |
3902 |
|
520c8b165 vfs: add renameat... |
3903 3904 |
if (flags && !old_dir->i_op->rename2) return -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
3905 3906 3907 3908 |
/* * If we are going to change the parent - check write permissions, * we'll need to flip '..'. */ |
da1ce0670 vfs: add cross-re... |
3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 |
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 |
3920 |
} |
0b3974eb0 security: add fla... |
3921 3922 |
error = security_inode_rename(old_dir, old_dentry, new_dir, new_dentry, flags); |
1da177e4c Linux-2.6.12-rc2 |
3923 3924 |
if (error) return error; |
bc27027a7 vfs: rename: use ... |
3925 |
old_name = fsnotify_oldname_init(old_dentry->d_name.name); |
1d2ef5901 restore pinning t... |
3926 |
dget(new_dentry); |
da1ce0670 vfs: add cross-re... |
3927 |
if (!is_dir || (flags & RENAME_EXCHANGE)) |
bc27027a7 vfs: rename: use ... |
3928 3929 |
lock_two_nondirectories(source, target); else if (target) |
1b1dcc1b5 [PATCH] mutex sub... |
3930 |
mutex_lock(&target->i_mutex); |
9055cba71 vfs: clean up vfs... |
3931 3932 3933 3934 |
error = -EBUSY; if (d_mountpoint(old_dentry) || d_mountpoint(new_dentry)) goto out; |
da1ce0670 vfs: add cross-re... |
3935 |
if (max_links && new_dir != old_dir) { |
bc27027a7 vfs: rename: use ... |
3936 |
error = -EMLINK; |
da1ce0670 vfs: add cross-re... |
3937 |
if (is_dir && !new_is_dir && new_dir->i_nlink >= max_links) |
bc27027a7 vfs: rename: use ... |
3938 |
goto out; |
da1ce0670 vfs: add cross-re... |
3939 3940 3941 3942 3943 3944 3945 |
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 ... |
3946 |
error = try_break_deleg(source, delegated_inode); |
8e6d782ca locks: break dele... |
3947 3948 |
if (error) goto out; |
da1ce0670 vfs: add cross-re... |
3949 3950 3951 3952 3953 |
} if (target && !new_is_dir) { error = try_break_deleg(target, delegated_inode); if (error) goto out; |
8e6d782ca locks: break dele... |
3954 |
} |
520c8b165 vfs: add renameat... |
3955 3956 3957 3958 3959 3960 3961 |
if (!flags) { error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry); } else { error = old_dir->i_op->rename2(old_dir, old_dentry, new_dir, new_dentry, flags); } |
51892bbb5 vfs: clean up vfs... |
3962 3963 |
if (error) goto out; |
da1ce0670 vfs: add cross-re... |
3964 |
if (!(flags & RENAME_EXCHANGE) && target) { |
bc27027a7 vfs: rename: use ... |
3965 3966 |
if (is_dir) target->i_flags |= S_DEAD; |
51892bbb5 vfs: clean up vfs... |
3967 |
dont_mount(new_dentry); |
bc27027a7 vfs: rename: use ... |
3968 |
} |
da1ce0670 vfs: add cross-re... |
3969 3970 3971 3972 3973 3974 |
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... |
3975 |
out: |
da1ce0670 vfs: add cross-re... |
3976 |
if (!is_dir || (flags & RENAME_EXCHANGE)) |
bc27027a7 vfs: rename: use ... |
3977 3978 3979 |
unlock_two_nondirectories(source, target); else if (target) mutex_unlock(&target->i_mutex); |
1da177e4c Linux-2.6.12-rc2 |
3980 |
dput(new_dentry); |
da1ce0670 vfs: add cross-re... |
3981 |
if (!error) { |
123df2944 Lose the new_name... |
3982 |
fsnotify_move(old_dir, new_dir, old_name, is_dir, |
da1ce0670 vfs: add cross-re... |
3983 3984 3985 3986 3987 3988 |
!(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 |
3989 |
fsnotify_oldname_free(old_name); |
1da177e4c Linux-2.6.12-rc2 |
3990 3991 |
return error; } |
4d3595073 namei.c: move EXP... |
3992 |
EXPORT_SYMBOL(vfs_rename); |
1da177e4c Linux-2.6.12-rc2 |
3993 |
|
520c8b165 vfs: add renameat... |
3994 3995 |
SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname, int, newdfd, const char __user *, newname, unsigned int, flags) |
1da177e4c Linux-2.6.12-rc2 |
3996 |
{ |
2ad94ae65 [PATCH] new (loca... |
3997 3998 3999 |
struct dentry *old_dir, *new_dir; struct dentry *old_dentry, *new_dentry; struct dentry *trap; |
1da177e4c Linux-2.6.12-rc2 |
4000 |
struct nameidata oldnd, newnd; |
8e6d782ca locks: break dele... |
4001 |
struct inode *delegated_inode = NULL; |
91a27b2a7 vfs: define struc... |
4002 4003 |
struct filename *from; struct filename *to; |
c6a942840 vfs: fix renameat... |
4004 4005 |
unsigned int lookup_flags = 0; bool should_retry = false; |
2ad94ae65 [PATCH] new (loca... |
4006 |
int error; |
520c8b165 vfs: add renameat... |
4007 |
|
da1ce0670 vfs: add cross-re... |
4008 4009 4010 4011 |
if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE)) return -EINVAL; if ((flags & RENAME_NOREPLACE) && (flags & RENAME_EXCHANGE)) |
520c8b165 vfs: add renameat... |
4012 |
return -EINVAL; |
c6a942840 vfs: fix renameat... |
4013 4014 |
retry: from = user_path_parent(olddfd, oldname, &oldnd, lookup_flags); |
91a27b2a7 vfs: define struc... |
4015 4016 |
if (IS_ERR(from)) { error = PTR_ERR(from); |
1da177e4c Linux-2.6.12-rc2 |
4017 |
goto exit; |
91a27b2a7 vfs: define struc... |
4018 |
} |
1da177e4c Linux-2.6.12-rc2 |
4019 |
|
c6a942840 vfs: fix renameat... |
4020 |
to = user_path_parent(newdfd, newname, &newnd, lookup_flags); |
91a27b2a7 vfs: define struc... |
4021 4022 |
if (IS_ERR(to)) { error = PTR_ERR(to); |
1da177e4c Linux-2.6.12-rc2 |
4023 |
goto exit1; |
91a27b2a7 vfs: define struc... |
4024 |
} |
1da177e4c Linux-2.6.12-rc2 |
4025 4026 |
error = -EXDEV; |
4ac913785 Embed a struct pa... |
4027 |
if (oldnd.path.mnt != newnd.path.mnt) |
1da177e4c Linux-2.6.12-rc2 |
4028 |
goto exit2; |
4ac913785 Embed a struct pa... |
4029 |
old_dir = oldnd.path.dentry; |
1da177e4c Linux-2.6.12-rc2 |
4030 4031 4032 |
error = -EBUSY; if (oldnd.last_type != LAST_NORM) goto exit2; |
4ac913785 Embed a struct pa... |
4033 |
new_dir = newnd.path.dentry; |
0a7c3937a vfs: add RENAME_N... |
4034 4035 |
if (flags & RENAME_NOREPLACE) error = -EEXIST; |
1da177e4c Linux-2.6.12-rc2 |
4036 4037 |
if (newnd.last_type != LAST_NORM) goto exit2; |
c30dabfe5 fs: Push mnt_want... |
4038 4039 4040 |
error = mnt_want_write(oldnd.path.mnt); if (error) goto exit2; |
0612d9fb2 [PATCH vfs-2.6 5/... |
4041 4042 |
oldnd.flags &= ~LOOKUP_PARENT; newnd.flags &= ~LOOKUP_PARENT; |
da1ce0670 vfs: add cross-re... |
4043 4044 |
if (!(flags & RENAME_EXCHANGE)) newnd.flags |= LOOKUP_RENAME_TARGET; |
0612d9fb2 [PATCH vfs-2.6 5/... |
4045 |
|
8e6d782ca locks: break dele... |
4046 |
retry_deleg: |
1da177e4c Linux-2.6.12-rc2 |
4047 |
trap = lock_rename(new_dir, old_dir); |
49705b774 [PATCH] sanitize ... |
4048 |
old_dentry = lookup_hash(&oldnd); |
1da177e4c Linux-2.6.12-rc2 |
4049 4050 4051 4052 4053 |
error = PTR_ERR(old_dentry); if (IS_ERR(old_dentry)) goto exit3; /* source must exist */ error = -ENOENT; |
b18825a7c VFS: Put a small ... |
4054 |
if (d_is_negative(old_dentry)) |
1da177e4c Linux-2.6.12-rc2 |
4055 |
goto exit4; |
0a7c3937a vfs: add RENAME_N... |
4056 4057 4058 4059 4060 4061 4062 |
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... |
4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 |
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 |
4074 |
/* unless the source is a directory trailing slashes give -ENOTDIR */ |
44b1d5304 vfs: add d_is_dir() |
4075 |
if (!d_is_dir(old_dentry)) { |
1da177e4c Linux-2.6.12-rc2 |
4076 4077 |
error = -ENOTDIR; if (oldnd.last.name[oldnd.last.len]) |
0a7c3937a vfs: add RENAME_N... |
4078 |
goto exit5; |
da1ce0670 vfs: add cross-re... |
4079 |
if (!(flags & RENAME_EXCHANGE) && newnd.last.name[newnd.last.len]) |
0a7c3937a vfs: add RENAME_N... |
4080 |
goto exit5; |
1da177e4c Linux-2.6.12-rc2 |
4081 4082 4083 4084 |
} /* source should not be ancestor of target */ error = -EINVAL; if (old_dentry == trap) |
0a7c3937a vfs: add RENAME_N... |
4085 |
goto exit5; |
1da177e4c Linux-2.6.12-rc2 |
4086 |
/* target should not be an ancestor of source */ |
da1ce0670 vfs: add cross-re... |
4087 4088 |
if (!(flags & RENAME_EXCHANGE)) error = -ENOTEMPTY; |
1da177e4c Linux-2.6.12-rc2 |
4089 4090 |
if (new_dentry == trap) goto exit5; |
be6d3e56a introduce new LSM... |
4091 |
error = security_path_rename(&oldnd.path, old_dentry, |
0b3974eb0 security: add fla... |
4092 |
&newnd.path, new_dentry, flags); |
be6d3e56a introduce new LSM... |
4093 |
if (error) |
c30dabfe5 fs: Push mnt_want... |
4094 |
goto exit5; |
1da177e4c Linux-2.6.12-rc2 |
4095 |
error = vfs_rename(old_dir->d_inode, old_dentry, |
520c8b165 vfs: add renameat... |
4096 4097 |
new_dir->d_inode, new_dentry, &delegated_inode, flags); |
1da177e4c Linux-2.6.12-rc2 |
4098 4099 4100 4101 4102 4103 |
exit5: dput(new_dentry); exit4: dput(old_dentry); exit3: unlock_rename(new_dir, old_dir); |
8e6d782ca locks: break dele... |
4104 4105 4106 4107 4108 |
if (delegated_inode) { error = break_deleg_wait(&delegated_inode); if (!error) goto retry_deleg; } |
c30dabfe5 fs: Push mnt_want... |
4109 |
mnt_drop_write(oldnd.path.mnt); |
1da177e4c Linux-2.6.12-rc2 |
4110 |
exit2: |
c6a942840 vfs: fix renameat... |
4111 4112 |
if (retry_estale(error, lookup_flags)) should_retry = true; |
1d957f9bf Introduce path_put() |
4113 |
path_put(&newnd.path); |
2ad94ae65 [PATCH] new (loca... |
4114 |
putname(to); |
1da177e4c Linux-2.6.12-rc2 |
4115 |
exit1: |
1d957f9bf Introduce path_put() |
4116 |
path_put(&oldnd.path); |
1da177e4c Linux-2.6.12-rc2 |
4117 |
putname(from); |
c6a942840 vfs: fix renameat... |
4118 4119 4120 4121 4122 |
if (should_retry) { should_retry = false; lookup_flags |= LOOKUP_REVAL; goto retry; } |
2ad94ae65 [PATCH] new (loca... |
4123 |
exit: |
1da177e4c Linux-2.6.12-rc2 |
4124 4125 |
return error; } |
520c8b165 vfs: add renameat... |
4126 4127 4128 4129 4130 |
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... |
4131 |
SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newname) |
5590ff0d5 [PATCH] vfs: *at ... |
4132 |
{ |
520c8b165 vfs: add renameat... |
4133 |
return sys_renameat2(AT_FDCWD, oldname, AT_FDCWD, newname, 0); |
5590ff0d5 [PATCH] vfs: *at ... |
4134 |
} |
5d826c847 new helper: readl... |
4135 |
int readlink_copy(char __user *buffer, int buflen, const char *link) |
1da177e4c Linux-2.6.12-rc2 |
4136 |
{ |
5d826c847 new helper: readl... |
4137 |
int len = PTR_ERR(link); |
1da177e4c Linux-2.6.12-rc2 |
4138 4139 4140 4141 4142 4143 4144 4145 4146 4147 4148 |
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... |
4149 |
EXPORT_SYMBOL(readlink_copy); |
1da177e4c Linux-2.6.12-rc2 |
4150 4151 4152 4153 4154 4155 4156 4157 4158 |
/* * 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... |
4159 |
void *cookie; |
694a1764d [patch 3/4] vfs: ... |
4160 |
int res; |
cc314eef0 Fix nasty ncpfs s... |
4161 |
|
1da177e4c Linux-2.6.12-rc2 |
4162 |
nd.depth = 0; |
cc314eef0 Fix nasty ncpfs s... |
4163 |
cookie = dentry->d_inode->i_op->follow_link(dentry, &nd); |
694a1764d [patch 3/4] vfs: ... |
4164 4165 |
if (IS_ERR(cookie)) return PTR_ERR(cookie); |
5d826c847 new helper: readl... |
4166 |
res = readlink_copy(buffer, buflen, nd_get_link(&nd)); |
694a1764d [patch 3/4] vfs: ... |
4167 4168 4169 |
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 |
4170 |
} |
4d3595073 namei.c: move EXP... |
4171 |
EXPORT_SYMBOL(generic_readlink); |
1da177e4c Linux-2.6.12-rc2 |
4172 |
|
1da177e4c Linux-2.6.12-rc2 |
4173 4174 4175 |
/* get the link contents into pagecache */ static char *page_getlink(struct dentry * dentry, struct page **ppage) { |
ebd09abbd vfs: ensure page ... |
4176 4177 |
char *kaddr; struct page *page; |
1da177e4c Linux-2.6.12-rc2 |
4178 |
struct address_space *mapping = dentry->d_inode->i_mapping; |
090d2b185 [PATCH] read_mapp... |
4179 |
page = read_mapping_page(mapping, 0, NULL); |
1da177e4c Linux-2.6.12-rc2 |
4180 |
if (IS_ERR(page)) |
6fe6900e1 mm: make read_cac... |
4181 |
return (char*)page; |
1da177e4c Linux-2.6.12-rc2 |
4182 |
*ppage = page; |
ebd09abbd vfs: ensure page ... |
4183 4184 4185 |
kaddr = kmap(page); nd_terminate_link(kaddr, dentry->d_inode->i_size, PAGE_SIZE - 1); return kaddr; |
1da177e4c Linux-2.6.12-rc2 |
4186 4187 4188 4189 4190 |
} int page_readlink(struct dentry *dentry, char __user *buffer, int buflen) { struct page *page = NULL; |
5d826c847 new helper: readl... |
4191 |
int res = readlink_copy(buffer, buflen, page_getlink(dentry, &page)); |
1da177e4c Linux-2.6.12-rc2 |
4192 4193 4194 4195 4196 4197 |
if (page) { kunmap(page); page_cache_release(page); } return res; } |
4d3595073 namei.c: move EXP... |
4198 |
EXPORT_SYMBOL(page_readlink); |
1da177e4c Linux-2.6.12-rc2 |
4199 |
|
cc314eef0 Fix nasty ncpfs s... |
4200 |
void *page_follow_link_light(struct dentry *dentry, struct nameidata *nd) |
1da177e4c Linux-2.6.12-rc2 |
4201 |
{ |
cc314eef0 Fix nasty ncpfs s... |
4202 |
struct page *page = NULL; |
1da177e4c Linux-2.6.12-rc2 |
4203 |
nd_set_link(nd, page_getlink(dentry, &page)); |
cc314eef0 Fix nasty ncpfs s... |
4204 |
return page; |
1da177e4c Linux-2.6.12-rc2 |
4205 |
} |
4d3595073 namei.c: move EXP... |
4206 |
EXPORT_SYMBOL(page_follow_link_light); |
1da177e4c Linux-2.6.12-rc2 |
4207 |
|
cc314eef0 Fix nasty ncpfs s... |
4208 |
void page_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie) |
1da177e4c Linux-2.6.12-rc2 |
4209 |
{ |
cc314eef0 Fix nasty ncpfs s... |
4210 4211 4212 |
struct page *page = cookie; if (page) { |
1da177e4c Linux-2.6.12-rc2 |
4213 4214 |
kunmap(page); page_cache_release(page); |
1da177e4c Linux-2.6.12-rc2 |
4215 4216 |
} } |
4d3595073 namei.c: move EXP... |
4217 |
EXPORT_SYMBOL(page_put_link); |
1da177e4c Linux-2.6.12-rc2 |
4218 |
|
54566b2c1 fs: symlink write... |
4219 4220 4221 4222 |
/* * 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 |
4223 4224 |
{ struct address_space *mapping = inode->i_mapping; |
0adb25d2e [PATCH] ext3: ext... |
4225 |
struct page *page; |
afddba49d fs: introduce wri... |
4226 |
void *fsdata; |
beb497ab4 [PATCH] __page_sy... |
4227 |
int err; |
1da177e4c Linux-2.6.12-rc2 |
4228 |
char *kaddr; |
54566b2c1 fs: symlink write... |
4229 4230 4231 |
unsigned int flags = AOP_FLAG_UNINTERRUPTIBLE; if (nofs) flags |= AOP_FLAG_NOFS; |
1da177e4c Linux-2.6.12-rc2 |
4232 |
|
7e53cac41 [PATCH] Honour AO... |
4233 |
retry: |
afddba49d fs: introduce wri... |
4234 |
err = pagecache_write_begin(NULL, mapping, 0, len-1, |
54566b2c1 fs: symlink write... |
4235 |
flags, &page, &fsdata); |
1da177e4c Linux-2.6.12-rc2 |
4236 |
if (err) |
afddba49d fs: introduce wri... |
4237 |
goto fail; |
e8e3c3d66 fs: remove the se... |
4238 |
kaddr = kmap_atomic(page); |
1da177e4c Linux-2.6.12-rc2 |
4239 |
memcpy(kaddr, symname, len-1); |
e8e3c3d66 fs: remove the se... |
4240 |
kunmap_atomic(kaddr); |
afddba49d fs: introduce wri... |
4241 4242 4243 |
err = pagecache_write_end(NULL, mapping, 0, len-1, len-1, page, fsdata); |
1da177e4c Linux-2.6.12-rc2 |
4244 4245 |
if (err < 0) goto fail; |
afddba49d fs: introduce wri... |
4246 4247 |
if (err < len-1) goto retry; |
1da177e4c Linux-2.6.12-rc2 |
4248 4249 |
mark_inode_dirty(inode); return 0; |
1da177e4c Linux-2.6.12-rc2 |
4250 4251 4252 |
fail: return err; } |
4d3595073 namei.c: move EXP... |
4253 |
EXPORT_SYMBOL(__page_symlink); |
1da177e4c Linux-2.6.12-rc2 |
4254 |
|
0adb25d2e [PATCH] ext3: ext... |
4255 4256 4257 |
int page_symlink(struct inode *inode, const char *symname, int len) { return __page_symlink(inode, symname, len, |
54566b2c1 fs: symlink write... |
4258 |
!(mapping_gfp_mask(inode->i_mapping) & __GFP_FS)); |
0adb25d2e [PATCH] ext3: ext... |
4259 |
} |
4d3595073 namei.c: move EXP... |
4260 |
EXPORT_SYMBOL(page_symlink); |
0adb25d2e [PATCH] ext3: ext... |
4261 |
|
92e1d5be9 [PATCH] mark stru... |
4262 |
const struct inode_operations page_symlink_inode_operations = { |
1da177e4c Linux-2.6.12-rc2 |
4263 4264 4265 4266 |
.readlink = generic_readlink, .follow_link = page_follow_link_light, .put_link = page_put_link, }; |
1da177e4c Linux-2.6.12-rc2 |
4267 |
EXPORT_SYMBOL(page_symlink_inode_operations); |