diff options
| -rw-r--r-- | fs/namei.c | 48 | ||||
| -rw-r--r-- | include/linux/fs.h | 1 |
2 files changed, 32 insertions, 17 deletions
diff --git a/fs/namei.c b/fs/namei.c index f09edf3eeef..caf090c4862 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -315,6 +315,36 @@ static inline int do_inode_permission(struct inode *inode, int mask) } /** + * inode_only_permission - check access rights to a given inode only + * @inode: inode to check permissions on + * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC, ...) + * + * Uses to check read/write/execute permissions on an inode directly, we do + * not check filesystem permissions. + */ +int inode_only_permission(struct inode *inode, int mask) +{ + int retval; + + /* + * Nobody gets write access to an immutable file. + */ + if (unlikely(mask & MAY_WRITE) && IS_IMMUTABLE(inode)) + return -EACCES; + + retval = do_inode_permission(inode, mask); + if (retval) + return retval; + + retval = devcgroup_inode_permission(inode, mask); + if (retval) + return retval; + + return security_inode_permission(inode, mask); +} +EXPORT_SYMBOL(inode_only_permission); + +/** * 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, ...) @@ -328,8 +358,6 @@ static inline int do_inode_permission(struct inode *inode, int mask) */ int inode_permission(struct inode *inode, int mask) { - int retval; - if (unlikely(mask & MAY_WRITE)) { umode_t mode = inode->i_mode; @@ -339,23 +367,9 @@ int inode_permission(struct inode *inode, int mask) if (IS_RDONLY(inode) && (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) return -EROFS; - - /* - * Nobody gets write access to an immutable file. - */ - if (IS_IMMUTABLE(inode)) - return -EACCES; } - retval = do_inode_permission(inode, mask); - if (retval) - return retval; - - retval = devcgroup_inode_permission(inode, mask); - if (retval) - return retval; - - return security_inode_permission(inode, mask); + return inode_only_permission(inode, mask); } /** diff --git a/include/linux/fs.h b/include/linux/fs.h index 49b86cf0564..e99bb48293d 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2263,6 +2263,7 @@ extern sector_t bmap(struct inode *, sector_t); #endif extern int notify_change(struct dentry *, struct iattr *); extern int inode_permission(struct inode *, int); +extern int inode_only_permission(struct inode *, int); extern int generic_permission(struct inode *, int); static inline bool execute_ok(struct inode *inode) |