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fs/posix_acl.c
21.5 KB
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// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* Copyright (C) 2002,2003 by Andreas Gruenbacher <a.gruenbacher@computer.org> |
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* |
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* Fixes from William Schumacher incorporated on 15 March 2001. * (Reported by Charles Bertsch, <CBertsch@microtest.com>). |
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*/ /* * This file contains generic functions for manipulating * POSIX 1003.1e draft standard 17 ACLs. */ #include <linux/kernel.h> #include <linux/slab.h> |
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#include <linux/atomic.h> |
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#include <linux/fs.h> #include <linux/sched.h> |
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#include <linux/cred.h> |
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#include <linux/posix_acl.h> |
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#include <linux/posix_acl_xattr.h> |
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#include <linux/xattr.h> |
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#include <linux/export.h> |
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#include <linux/user_namespace.h> |
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static struct posix_acl **acl_by_type(struct inode *inode, int type) |
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{ switch (type) { case ACL_TYPE_ACCESS: return &inode->i_acl; case ACL_TYPE_DEFAULT: return &inode->i_default_acl; default: BUG(); } } |
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struct posix_acl *get_cached_acl(struct inode *inode, int type) { struct posix_acl **p = acl_by_type(inode, type); |
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struct posix_acl *acl; for (;;) { rcu_read_lock(); acl = rcu_dereference(*p); if (!acl || is_uncached_acl(acl) || |
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refcount_inc_not_zero(&acl->a_refcount)) |
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break; rcu_read_unlock(); cpu_relax(); |
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} |
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rcu_read_unlock(); |
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return acl; } EXPORT_SYMBOL(get_cached_acl); struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type) { return rcu_dereference(*acl_by_type(inode, type)); } EXPORT_SYMBOL(get_cached_acl_rcu); void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl) { struct posix_acl **p = acl_by_type(inode, type); struct posix_acl *old; |
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old = xchg(p, posix_acl_dup(acl)); if (!is_uncached_acl(old)) |
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posix_acl_release(old); } EXPORT_SYMBOL(set_cached_acl); |
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static void __forget_cached_acl(struct posix_acl **p) |
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{ |
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struct posix_acl *old; |
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old = xchg(p, ACL_NOT_CACHED); if (!is_uncached_acl(old)) |
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posix_acl_release(old); } |
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void forget_cached_acl(struct inode *inode, int type) { __forget_cached_acl(acl_by_type(inode, type)); } |
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EXPORT_SYMBOL(forget_cached_acl); void forget_all_cached_acls(struct inode *inode) { |
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__forget_cached_acl(&inode->i_acl); __forget_cached_acl(&inode->i_default_acl); |
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} EXPORT_SYMBOL(forget_all_cached_acls); |
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struct posix_acl *get_acl(struct inode *inode, int type) { |
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void *sentinel; struct posix_acl **p; |
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struct posix_acl *acl; |
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/* * The sentinel is used to detect when another operation like * set_cached_acl() or forget_cached_acl() races with get_acl(). * It is guaranteed that is_uncached_acl(sentinel) is true. */ |
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acl = get_cached_acl(inode, type); |
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if (!is_uncached_acl(acl)) |
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return acl; if (!IS_POSIXACL(inode)) return NULL; |
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sentinel = uncached_acl_sentinel(current); p = acl_by_type(inode, type); /* * If the ACL isn't being read yet, set our sentinel. Otherwise, the * current value of the ACL will not be ACL_NOT_CACHED and so our own * sentinel will not be set; another task will update the cache. We * could wait for that other task to complete its job, but it's easier * to just call ->get_acl to fetch the ACL ourself. (This is going to * be an unlikely race.) */ if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) /* fall through */ ; |
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/* |
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* Normally, the ACL returned by ->get_acl will be cached. * A filesystem can prevent that by calling * forget_cached_acl(inode, type) in ->get_acl. |
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* * If the filesystem doesn't have a get_acl() function at all, we'll * just create the negative cache entry. */ if (!inode->i_op->get_acl) { set_cached_acl(inode, type, NULL); return NULL; } |
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acl = inode->i_op->get_acl(inode, type); if (IS_ERR(acl)) { /* * Remove our sentinel so that we don't block future attempts * to cache the ACL. */ cmpxchg(p, sentinel, ACL_NOT_CACHED); return acl; } /* * Cache the result, but only if our sentinel is still in place. */ posix_acl_dup(acl); if (unlikely(cmpxchg(p, sentinel, acl) != sentinel)) posix_acl_release(acl); return acl; |
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} EXPORT_SYMBOL(get_acl); |
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/* |
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* Init a fresh posix_acl */ void posix_acl_init(struct posix_acl *acl, int count) { |
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refcount_set(&acl->a_refcount, 1); |
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acl->a_count = count; } |
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EXPORT_SYMBOL(posix_acl_init); |
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/* |
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* Allocate a new ACL with the specified number of entries. */ struct posix_acl * |
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posix_acl_alloc(int count, gfp_t flags) |
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{ const size_t size = sizeof(struct posix_acl) + count * sizeof(struct posix_acl_entry); struct posix_acl *acl = kmalloc(size, flags); |
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if (acl) posix_acl_init(acl, count); |
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return acl; } |
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EXPORT_SYMBOL(posix_acl_alloc); |
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/* * Clone an ACL. */ |
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static struct posix_acl * |
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posix_acl_clone(const struct posix_acl *acl, gfp_t flags) |
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{ struct posix_acl *clone = NULL; if (acl) { int size = sizeof(struct posix_acl) + acl->a_count * sizeof(struct posix_acl_entry); |
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clone = kmemdup(acl, size, flags); if (clone) |
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refcount_set(&clone->a_refcount, 1); |
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} return clone; } /* * Check if an acl is valid. Returns 0 if it is, or -E... otherwise. */ int |
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posix_acl_valid(struct user_namespace *user_ns, const struct posix_acl *acl) |
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{ const struct posix_acl_entry *pa, *pe; int state = ACL_USER_OBJ; |
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int needs_mask = 0; FOREACH_ACL_ENTRY(pa, acl, pe) { if (pa->e_perm & ~(ACL_READ|ACL_WRITE|ACL_EXECUTE)) return -EINVAL; switch (pa->e_tag) { case ACL_USER_OBJ: if (state == ACL_USER_OBJ) { |
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state = ACL_USER; break; } return -EINVAL; case ACL_USER: if (state != ACL_USER) return -EINVAL; |
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if (!kuid_has_mapping(user_ns, pa->e_uid)) |
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return -EINVAL; |
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needs_mask = 1; break; case ACL_GROUP_OBJ: if (state == ACL_USER) { |
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state = ACL_GROUP; break; } return -EINVAL; case ACL_GROUP: if (state != ACL_GROUP) return -EINVAL; |
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if (!kgid_has_mapping(user_ns, pa->e_gid)) |
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return -EINVAL; |
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needs_mask = 1; break; case ACL_MASK: if (state != ACL_GROUP) return -EINVAL; state = ACL_OTHER; break; case ACL_OTHER: if (state == ACL_OTHER || (state == ACL_GROUP && !needs_mask)) { state = 0; break; } return -EINVAL; default: return -EINVAL; } } if (state == 0) return 0; return -EINVAL; } |
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EXPORT_SYMBOL(posix_acl_valid); |
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/* * Returns 0 if the acl can be exactly represented in the traditional * file mode permission bits, or else 1. Returns -E... on error. */ int |
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posix_acl_equiv_mode(const struct posix_acl *acl, umode_t *mode_p) |
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{ const struct posix_acl_entry *pa, *pe; |
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umode_t mode = 0; |
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int not_equiv = 0; |
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/* * A null ACL can always be presented as mode bits. */ if (!acl) return 0; |
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FOREACH_ACL_ENTRY(pa, acl, pe) { switch (pa->e_tag) { case ACL_USER_OBJ: mode |= (pa->e_perm & S_IRWXO) << 6; break; case ACL_GROUP_OBJ: mode |= (pa->e_perm & S_IRWXO) << 3; break; case ACL_OTHER: mode |= pa->e_perm & S_IRWXO; break; case ACL_MASK: mode = (mode & ~S_IRWXG) | ((pa->e_perm & S_IRWXO) << 3); not_equiv = 1; break; case ACL_USER: case ACL_GROUP: not_equiv = 1; break; default: return -EINVAL; } } if (mode_p) *mode_p = (*mode_p & ~S_IRWXUGO) | mode; return not_equiv; } |
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EXPORT_SYMBOL(posix_acl_equiv_mode); |
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/* * Create an ACL representing the file mode permission bits of an inode. */ struct posix_acl * |
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posix_acl_from_mode(umode_t mode, gfp_t flags) |
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{ struct posix_acl *acl = posix_acl_alloc(3, flags); if (!acl) return ERR_PTR(-ENOMEM); acl->a_entries[0].e_tag = ACL_USER_OBJ; |
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acl->a_entries[0].e_perm = (mode & S_IRWXU) >> 6; acl->a_entries[1].e_tag = ACL_GROUP_OBJ; |
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acl->a_entries[1].e_perm = (mode & S_IRWXG) >> 3; acl->a_entries[2].e_tag = ACL_OTHER; |
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acl->a_entries[2].e_perm = (mode & S_IRWXO); return acl; } |
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EXPORT_SYMBOL(posix_acl_from_mode); |
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/* * Return 0 if current is granted want access to the inode * by the acl. Returns -E... otherwise. */ int posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want) { const struct posix_acl_entry *pa, *pe, *mask_obj; int found = 0; |
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want &= MAY_READ | MAY_WRITE | MAY_EXEC | MAY_NOT_BLOCK; |
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FOREACH_ACL_ENTRY(pa, acl, pe) { switch(pa->e_tag) { case ACL_USER_OBJ: /* (May have been checked already) */ |
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if (uid_eq(inode->i_uid, current_fsuid())) |
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goto check_perm; break; case ACL_USER: |
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if (uid_eq(pa->e_uid, current_fsuid())) |
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goto mask; break; case ACL_GROUP_OBJ: if (in_group_p(inode->i_gid)) { found = 1; if ((pa->e_perm & want) == want) goto mask; } break; case ACL_GROUP: |
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if (in_group_p(pa->e_gid)) { |
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found = 1; if ((pa->e_perm & want) == want) goto mask; } break; case ACL_MASK: break; case ACL_OTHER: if (found) return -EACCES; else goto check_perm; default: return -EIO; } } return -EIO; mask: for (mask_obj = pa+1; mask_obj != pe; mask_obj++) { if (mask_obj->e_tag == ACL_MASK) { if ((pa->e_perm & mask_obj->e_perm & want) == want) return 0; return -EACCES; } } check_perm: if ((pa->e_perm & want) == want) return 0; return -EACCES; } /* * Modify acl when creating a new inode. The caller must ensure the acl is * only referenced once. * * mode_p initially must contain the mode parameter to the open() / creat() * system calls. All permissions that are not granted by the acl are removed. * The permissions in the acl are changed to reflect the mode_p parameter. */ |
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static int posix_acl_create_masq(struct posix_acl *acl, umode_t *mode_p) |
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{ struct posix_acl_entry *pa, *pe; struct posix_acl_entry *group_obj = NULL, *mask_obj = NULL; |
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umode_t mode = *mode_p; |
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int not_equiv = 0; /* assert(atomic_read(acl->a_refcount) == 1); */ FOREACH_ACL_ENTRY(pa, acl, pe) { switch(pa->e_tag) { case ACL_USER_OBJ: pa->e_perm &= (mode >> 6) | ~S_IRWXO; mode &= (pa->e_perm << 6) | ~S_IRWXU; break; case ACL_USER: case ACL_GROUP: not_equiv = 1; break; case ACL_GROUP_OBJ: group_obj = pa; break; case ACL_OTHER: pa->e_perm &= mode | ~S_IRWXO; mode &= pa->e_perm | ~S_IRWXO; break; case ACL_MASK: mask_obj = pa; not_equiv = 1; break; default: return -EIO; } } if (mask_obj) { mask_obj->e_perm &= (mode >> 3) | ~S_IRWXO; mode &= (mask_obj->e_perm << 3) | ~S_IRWXG; } else { if (!group_obj) return -EIO; group_obj->e_perm &= (mode >> 3) | ~S_IRWXO; mode &= (group_obj->e_perm << 3) | ~S_IRWXG; } *mode_p = (*mode_p & ~S_IRWXUGO) | mode; return not_equiv; } /* * Modify the ACL for the chmod syscall. */ |
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static int __posix_acl_chmod_masq(struct posix_acl *acl, umode_t mode) |
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{ struct posix_acl_entry *group_obj = NULL, *mask_obj = NULL; struct posix_acl_entry *pa, *pe; /* assert(atomic_read(acl->a_refcount) == 1); */ FOREACH_ACL_ENTRY(pa, acl, pe) { switch(pa->e_tag) { case ACL_USER_OBJ: pa->e_perm = (mode & S_IRWXU) >> 6; break; case ACL_USER: case ACL_GROUP: break; case ACL_GROUP_OBJ: group_obj = pa; break; case ACL_MASK: mask_obj = pa; break; case ACL_OTHER: pa->e_perm = (mode & S_IRWXO); break; default: return -EIO; } } if (mask_obj) { mask_obj->e_perm = (mode & S_IRWXG) >> 3; } else { if (!group_obj) return -EIO; group_obj->e_perm = (mode & S_IRWXG) >> 3; } return 0; } |
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int |
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__posix_acl_create(struct posix_acl **acl, gfp_t gfp, umode_t *mode_p) |
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{ struct posix_acl *clone = posix_acl_clone(*acl, gfp); int err = -ENOMEM; if (clone) { err = posix_acl_create_masq(clone, mode_p); if (err < 0) { posix_acl_release(clone); clone = NULL; } } posix_acl_release(*acl); *acl = clone; return err; } |
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EXPORT_SYMBOL(__posix_acl_create); |
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int |
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__posix_acl_chmod(struct posix_acl **acl, gfp_t gfp, umode_t mode) |
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{ struct posix_acl *clone = posix_acl_clone(*acl, gfp); int err = -ENOMEM; if (clone) { |
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err = __posix_acl_chmod_masq(clone, mode); |
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if (err) { posix_acl_release(clone); clone = NULL; } } posix_acl_release(*acl); *acl = clone; return err; } |
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EXPORT_SYMBOL(__posix_acl_chmod); int |
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posix_acl_chmod(struct inode *inode, umode_t mode) |
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{ struct posix_acl *acl; int ret = 0; if (!IS_POSIXACL(inode)) return 0; if (!inode->i_op->set_acl) return -EOPNOTSUPP; acl = get_acl(inode, ACL_TYPE_ACCESS); |
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if (IS_ERR_OR_NULL(acl)) { if (acl == ERR_PTR(-EOPNOTSUPP)) return 0; |
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return PTR_ERR(acl); |
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} |
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ret = __posix_acl_chmod(&acl, GFP_KERNEL, mode); |
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if (ret) return ret; ret = inode->i_op->set_acl(inode, acl, ACL_TYPE_ACCESS); posix_acl_release(acl); return ret; } |
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EXPORT_SYMBOL(posix_acl_chmod); |
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int posix_acl_create(struct inode *dir, umode_t *mode, struct posix_acl **default_acl, struct posix_acl **acl) { struct posix_acl *p; |
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struct posix_acl *clone; |
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int ret; |
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*acl = NULL; *default_acl = NULL; |
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if (S_ISLNK(*mode) || !IS_POSIXACL(dir)) |
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return 0; |
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p = get_acl(dir, ACL_TYPE_DEFAULT); |
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if (!p || p == ERR_PTR(-EOPNOTSUPP)) { *mode &= ~current_umask(); return 0; |
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} |
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if (IS_ERR(p)) return PTR_ERR(p); |
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ret = -ENOMEM; |
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clone = posix_acl_clone(p, GFP_NOFS); if (!clone) |
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goto err_release; |
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ret = posix_acl_create_masq(clone, mode); |
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if (ret < 0) |
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goto err_release_clone; |
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if (ret == 0) posix_acl_release(clone); else *acl = clone; |
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if (!S_ISDIR(*mode)) |
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posix_acl_release(p); |
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else |
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*default_acl = p; |
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return 0; |
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err_release_clone: |
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posix_acl_release(clone); |
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err_release: |
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posix_acl_release(p); |
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return ret; |
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} EXPORT_SYMBOL_GPL(posix_acl_create); |
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/** * posix_acl_update_mode - update mode in set_acl * * Update the file mode when setting an ACL: compute the new file permission * bits based on the ACL. In addition, if the ACL is equivalent to the new * file mode, set *acl to NULL to indicate that no ACL should be set. * * As with chmod, clear the setgit bit if the caller is not in the owning group * or capable of CAP_FSETID (see inode_change_ok). * * Called from set_acl inode operations. */ int posix_acl_update_mode(struct inode *inode, umode_t *mode_p, struct posix_acl **acl) { umode_t mode = inode->i_mode; int error; error = posix_acl_equiv_mode(*acl, &mode); if (error < 0) return error; if (error == 0) *acl = NULL; if (!in_group_p(inode->i_gid) && !capable_wrt_inode_uidgid(inode, CAP_FSETID)) mode &= ~S_ISGID; *mode_p = mode; return 0; } EXPORT_SYMBOL(posix_acl_update_mode); |
5c8ebd57b
|
649 650 651 652 653 654 655 |
/* * Fix up the uids and gids in posix acl extended attributes in place. */ static void posix_acl_fix_xattr_userns( struct user_namespace *to, struct user_namespace *from, void *value, size_t size) { |
2211d5ba5
|
656 657 |
struct posix_acl_xattr_header *header = value; struct posix_acl_xattr_entry *entry = (void *)(header + 1), *end; |
5c8ebd57b
|
658 659 660 661 662 663 |
int count; kuid_t uid; kgid_t gid; if (!value) return; |
2211d5ba5
|
664 |
if (size < sizeof(struct posix_acl_xattr_header)) |
5c8ebd57b
|
665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 |
return; if (header->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION)) return; count = posix_acl_xattr_count(size); if (count < 0) return; if (count == 0) return; for (end = entry + count; entry != end; entry++) { switch(le16_to_cpu(entry->e_tag)) { case ACL_USER: uid = make_kuid(from, le32_to_cpu(entry->e_id)); entry->e_id = cpu_to_le32(from_kuid(to, uid)); break; case ACL_GROUP: gid = make_kgid(from, le32_to_cpu(entry->e_id)); entry->e_id = cpu_to_le32(from_kgid(to, gid)); break; default: break; } } } void posix_acl_fix_xattr_from_user(void *value, size_t size) { struct user_namespace *user_ns = current_user_ns(); if (user_ns == &init_user_ns) return; posix_acl_fix_xattr_userns(&init_user_ns, user_ns, value, size); } void posix_acl_fix_xattr_to_user(void *value, size_t size) { struct user_namespace *user_ns = current_user_ns(); if (user_ns == &init_user_ns) return; posix_acl_fix_xattr_userns(user_ns, &init_user_ns, value, size); } /* * Convert from extended attribute to in-memory representation. */ struct posix_acl * posix_acl_from_xattr(struct user_namespace *user_ns, const void *value, size_t size) { |
2211d5ba5
|
714 715 |
const struct posix_acl_xattr_header *header = value; const struct posix_acl_xattr_entry *entry = (const void *)(header + 1), *end; |
5c8ebd57b
|
716 717 718 719 720 721 |
int count; struct posix_acl *acl; struct posix_acl_entry *acl_e; if (!value) return NULL; |
2211d5ba5
|
722 |
if (size < sizeof(struct posix_acl_xattr_header)) |
5c8ebd57b
|
723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 |
return ERR_PTR(-EINVAL); if (header->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION)) return ERR_PTR(-EOPNOTSUPP); count = posix_acl_xattr_count(size); if (count < 0) return ERR_PTR(-EINVAL); if (count == 0) return NULL; acl = posix_acl_alloc(count, GFP_NOFS); if (!acl) return ERR_PTR(-ENOMEM); acl_e = acl->a_entries; for (end = entry + count; entry != end; acl_e++, entry++) { acl_e->e_tag = le16_to_cpu(entry->e_tag); acl_e->e_perm = le16_to_cpu(entry->e_perm); switch(acl_e->e_tag) { case ACL_USER_OBJ: case ACL_GROUP_OBJ: case ACL_MASK: case ACL_OTHER: break; case ACL_USER: acl_e->e_uid = make_kuid(user_ns, le32_to_cpu(entry->e_id)); if (!uid_valid(acl_e->e_uid)) goto fail; break; case ACL_GROUP: acl_e->e_gid = make_kgid(user_ns, le32_to_cpu(entry->e_id)); if (!gid_valid(acl_e->e_gid)) goto fail; break; default: goto fail; } } return acl; fail: posix_acl_release(acl); return ERR_PTR(-EINVAL); } EXPORT_SYMBOL (posix_acl_from_xattr); /* * Convert from in-memory to extended attribute representation. */ int posix_acl_to_xattr(struct user_namespace *user_ns, const struct posix_acl *acl, void *buffer, size_t size) { |
2211d5ba5
|
783 784 |
struct posix_acl_xattr_header *ext_acl = buffer; struct posix_acl_xattr_entry *ext_entry; |
5c8ebd57b
|
785 786 787 788 789 790 791 |
int real_size, n; real_size = posix_acl_xattr_size(acl->a_count); if (!buffer) return real_size; if (real_size > size) return -ERANGE; |
47ba97344
|
792 |
|
2211d5ba5
|
793 |
ext_entry = (void *)(ext_acl + 1); |
5c8ebd57b
|
794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 |
ext_acl->a_version = cpu_to_le32(POSIX_ACL_XATTR_VERSION); for (n=0; n < acl->a_count; n++, ext_entry++) { const struct posix_acl_entry *acl_e = &acl->a_entries[n]; ext_entry->e_tag = cpu_to_le16(acl_e->e_tag); ext_entry->e_perm = cpu_to_le16(acl_e->e_perm); switch(acl_e->e_tag) { case ACL_USER: ext_entry->e_id = cpu_to_le32(from_kuid(user_ns, acl_e->e_uid)); break; case ACL_GROUP: ext_entry->e_id = cpu_to_le32(from_kgid(user_ns, acl_e->e_gid)); break; default: ext_entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID); break; } } return real_size; } EXPORT_SYMBOL (posix_acl_to_xattr); |
2aeccbe95
|
817 818 |
static int |
d9a82a040
|
819 |
posix_acl_xattr_get(const struct xattr_handler *handler, |
b296821a7
|
820 821 |
struct dentry *unused, struct inode *inode, const char *name, void *value, size_t size) |
2aeccbe95
|
822 823 824 |
{ struct posix_acl *acl; int error; |
b296821a7
|
825 |
if (!IS_POSIXACL(inode)) |
2aeccbe95
|
826 |
return -EOPNOTSUPP; |
b296821a7
|
827 |
if (S_ISLNK(inode->i_mode)) |
2aeccbe95
|
828 |
return -EOPNOTSUPP; |
b296821a7
|
829 |
acl = get_acl(inode, handler->flags); |
2aeccbe95
|
830 831 832 833 834 835 836 837 838 839 |
if (IS_ERR(acl)) return PTR_ERR(acl); if (acl == NULL) return -ENODATA; error = posix_acl_to_xattr(&init_user_ns, acl, value, size); posix_acl_release(acl); return error; } |
485e71e8f
|
840 841 |
int set_posix_acl(struct inode *inode, int type, struct posix_acl *acl) |
2aeccbe95
|
842 |
{ |
2aeccbe95
|
843 844 845 846 |
if (!IS_POSIXACL(inode)) return -EOPNOTSUPP; if (!inode->i_op->set_acl) return -EOPNOTSUPP; |
485e71e8f
|
847 848 |
if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode)) return acl ? -EACCES : 0; |
2aeccbe95
|
849 850 |
if (!inode_owner_or_capable(inode)) return -EPERM; |
485e71e8f
|
851 |
if (acl) { |
a867d7349
|
852 |
int ret = posix_acl_valid(inode->i_sb->s_user_ns, acl); |
485e71e8f
|
853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 |
if (ret) return ret; } return inode->i_op->set_acl(inode, acl, type); } EXPORT_SYMBOL(set_posix_acl); static int posix_acl_xattr_set(const struct xattr_handler *handler, struct dentry *unused, struct inode *inode, const char *name, const void *value, size_t size, int flags) { struct posix_acl *acl = NULL; int ret; |
2aeccbe95
|
868 869 870 871 |
if (value) { acl = posix_acl_from_xattr(&init_user_ns, value, size); if (IS_ERR(acl)) return PTR_ERR(acl); |
2aeccbe95
|
872 |
} |
485e71e8f
|
873 |
ret = set_posix_acl(inode, handler->flags, acl); |
2aeccbe95
|
874 875 876 |
posix_acl_release(acl); return ret; } |
764a5c6b1
|
877 878 |
static bool posix_acl_xattr_list(struct dentry *dentry) |
2aeccbe95
|
879 |
{ |
764a5c6b1
|
880 |
return IS_POSIXACL(d_backing_inode(dentry)); |
2aeccbe95
|
881 882 883 |
} const struct xattr_handler posix_acl_access_xattr_handler = { |
98e9cb571
|
884 |
.name = XATTR_NAME_POSIX_ACL_ACCESS, |
2aeccbe95
|
885 886 887 888 889 890 891 892 |
.flags = ACL_TYPE_ACCESS, .list = posix_acl_xattr_list, .get = posix_acl_xattr_get, .set = posix_acl_xattr_set, }; EXPORT_SYMBOL_GPL(posix_acl_access_xattr_handler); const struct xattr_handler posix_acl_default_xattr_handler = { |
98e9cb571
|
893 |
.name = XATTR_NAME_POSIX_ACL_DEFAULT, |
2aeccbe95
|
894 895 896 897 898 899 |
.flags = ACL_TYPE_DEFAULT, .list = posix_acl_xattr_list, .get = posix_acl_xattr_get, .set = posix_acl_xattr_set, }; EXPORT_SYMBOL_GPL(posix_acl_default_xattr_handler); |
feda821e7
|
900 901 902 903 904 905 |
int simple_set_acl(struct inode *inode, struct posix_acl *acl, int type) { int error; if (type == ACL_TYPE_ACCESS) { |
497de07d8
|
906 907 908 909 |
error = posix_acl_update_mode(inode, &inode->i_mode, &acl); if (error) return error; |
feda821e7
|
910 |
} |
078cd8279
|
911 |
inode->i_ctime = current_time(inode); |
feda821e7
|
912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 |
set_cached_acl(inode, type, acl); return 0; } int simple_acl_create(struct inode *dir, struct inode *inode) { struct posix_acl *default_acl, *acl; int error; error = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl); if (error) return error; set_cached_acl(inode, ACL_TYPE_DEFAULT, default_acl); set_cached_acl(inode, ACL_TYPE_ACCESS, acl); if (default_acl) posix_acl_release(default_acl); if (acl) posix_acl_release(acl); return 0; } |