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author | Steve French <sfrench@us.ibm.com> | 2005-11-09 14:33:22 -0800 |
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committer | Steve French <sfrench@us.ibm.com> | 2005-11-09 14:33:22 -0800 |
commit | e82b3aec8d508d2a925a4c766e97f16b7c4dfb1b (patch) | |
tree | 69d5685ef0c194f651a03e30bff14628b4d45400 /fs/namei.c | |
parent | ec58ef03284f0bfa50a04982b74c8c2325a0758e (diff) | |
parent | ad8f76be48d817b48222411ae16a7dfe257bdb24 (diff) | |
download | linux-e82b3aec8d508d2a925a4c766e97f16b7c4dfb1b.tar.bz2 |
Merge with /pub/scm/linux/kernel/git/torvalds/linux-2.6.git
Diffstat (limited to 'fs/namei.c')
-rw-r--r-- | fs/namei.c | 68 |
1 files changed, 51 insertions, 17 deletions
diff --git a/fs/namei.c b/fs/namei.c index c5769c4fcab1..6dbbd42d8b95 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -256,6 +256,38 @@ int permission(struct inode *inode, int mask, struct nameidata *nd) return security_inode_permission(inode, mask, nd); } +/** + * vfs_permission - check for access rights to a given path + * @nd: lookup result that describes the path + * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC) + * + * Used to check for read/write/execute permissions on a path. + * We use "fsuid" for this, letting us set arbitrary permissions + * for filesystem access without changing the "normal" uids which + * are used for other things. + */ +int vfs_permission(struct nameidata *nd, int mask) +{ + return permission(nd->dentry->d_inode, mask, nd); +} + +/** + * file_permission - check for additional access rights to a given file + * @file: file to check access rights for + * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC) + * + * Used to check for read/write/execute permissions on an already opened + * file. + * + * Note: + * Do not use this function in new code. All access checks should + * be done using vfs_permission(). + */ +int file_permission(struct file *file, int mask) +{ + return permission(file->f_dentry->d_inode, mask, NULL); +} + /* * get_write_access() gets write permission for a file. * put_write_access() releases this write permission. @@ -765,9 +797,8 @@ static fastcall int __link_path_walk(const char * name, struct nameidata *nd) nd->flags |= LOOKUP_CONTINUE; err = exec_permission_lite(inode, nd); - if (err == -EAGAIN) { - err = permission(inode, MAY_EXEC, nd); - } + if (err == -EAGAIN) + err = vfs_permission(nd, MAY_EXEC); if (err) break; @@ -1109,8 +1140,9 @@ int path_lookup_open(const char *name, unsigned int lookup_flags, * @open_flags: open intent flags * @create_mode: create intent flags */ -int path_lookup_create(const char *name, unsigned int lookup_flags, - struct nameidata *nd, int open_flags, int create_mode) +static int path_lookup_create(const char *name, unsigned int lookup_flags, + struct nameidata *nd, int open_flags, + int create_mode) { return __path_lookup_intent_open(name, lookup_flags|LOOKUP_CREATE, nd, open_flags, create_mode); @@ -1173,9 +1205,9 @@ out: return dentry; } -struct dentry * lookup_hash(struct qstr *name, struct dentry * base) +struct dentry * lookup_hash(struct nameidata *nd) { - return __lookup_hash(name, base, NULL); + return __lookup_hash(&nd->last, nd->dentry, nd); } /* SMP-safe */ @@ -1199,7 +1231,7 @@ struct dentry * lookup_one_len(const char * name, struct dentry * base, int len) } this.hash = end_name_hash(hash); - return lookup_hash(&this, base); + return __lookup_hash(&this, base, NULL); access: return ERR_PTR(-EACCES); } @@ -1407,7 +1439,7 @@ int may_open(struct nameidata *nd, int acc_mode, int flag) if (S_ISDIR(inode->i_mode) && (flag & FMODE_WRITE)) return -EISDIR; - error = permission(inode, acc_mode, nd); + error = vfs_permission(nd, acc_mode); if (error) return error; @@ -1459,7 +1491,7 @@ int may_open(struct nameidata *nd, int acc_mode, int flag) if (!error) { DQUOT_INIT(inode); - error = do_truncate(dentry, 0); + error = do_truncate(dentry, 0, NULL); } put_write_access(inode); if (error) @@ -1532,7 +1564,7 @@ int open_namei(const char * pathname, int flag, int mode, struct nameidata *nd) dir = nd->dentry; nd->flags &= ~LOOKUP_PARENT; down(&dir->d_inode->i_sem); - path.dentry = __lookup_hash(&nd->last, nd->dentry, nd); + path.dentry = lookup_hash(nd); path.mnt = nd->mnt; do_last: @@ -1634,7 +1666,7 @@ do_link: } dir = nd->dentry; down(&dir->d_inode->i_sem); - path.dentry = __lookup_hash(&nd->last, nd->dentry, nd); + path.dentry = lookup_hash(nd); path.mnt = nd->mnt; __putname(nd->last.name); goto do_last; @@ -1666,7 +1698,7 @@ struct dentry *lookup_create(struct nameidata *nd, int is_dir) /* * Do the final lookup. */ - dentry = lookup_hash(&nd->last, nd->dentry); + dentry = lookup_hash(nd); if (IS_ERR(dentry)) goto fail; @@ -1901,7 +1933,7 @@ asmlinkage long sys_rmdir(const char __user * pathname) goto exit1; } down(&nd.dentry->d_inode->i_sem); - dentry = lookup_hash(&nd.last, nd.dentry); + dentry = lookup_hash(&nd); error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { error = vfs_rmdir(nd.dentry->d_inode, dentry); @@ -1970,7 +2002,7 @@ asmlinkage long sys_unlink(const char __user * pathname) if (nd.last_type != LAST_NORM) goto exit1; down(&nd.dentry->d_inode->i_sem); - dentry = lookup_hash(&nd.last, nd.dentry); + dentry = lookup_hash(&nd); error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { /* Why not before? Because we want correct error value */ @@ -2313,7 +2345,7 @@ static inline int do_rename(const char * oldname, const char * newname) trap = lock_rename(new_dir, old_dir); - old_dentry = lookup_hash(&oldnd.last, old_dir); + old_dentry = lookup_hash(&oldnd); error = PTR_ERR(old_dentry); if (IS_ERR(old_dentry)) goto exit3; @@ -2333,7 +2365,7 @@ static inline int do_rename(const char * oldname, const char * newname) error = -EINVAL; if (old_dentry == trap) goto exit4; - new_dentry = lookup_hash(&newnd.last, new_dir); + new_dentry = lookup_hash(&newnd); error = PTR_ERR(new_dentry); if (IS_ERR(new_dentry)) goto exit4; @@ -2536,6 +2568,8 @@ EXPORT_SYMBOL(path_lookup); EXPORT_SYMBOL(path_release); EXPORT_SYMBOL(path_walk); EXPORT_SYMBOL(permission); +EXPORT_SYMBOL(vfs_permission); +EXPORT_SYMBOL(file_permission); EXPORT_SYMBOL(unlock_rename); EXPORT_SYMBOL(vfs_create); EXPORT_SYMBOL(vfs_follow_link); |