statx: correct error handling of NULL pathname

The change in commit 1e2f82d ("statx: Kill fd-with-NULL-path support in favour of AT_EMPTY_PATH") to error on a NULL pathname to statx() is inconsistent. It results in the error EINVAL for a NULL pathname. Other system calls with similar APIs (fchownat(), fstatat(), linkat()), return EFAULT. The solution is simply to remove the EINVAL check. As I already pointed out in [1], user_path_at*() and filename_lookup() will handle the NULL pathname as per the other APIs, to correctly produce the error EFAULT. [1] https://lkml.org/lkml/2017/4/26/561 Signed-off-by: Michael Kerrisk <[email protected]> Cc: David Howells <[email protected]> Cc: Al Viro <[email protected]> Cc: Eric Sandeen <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
devinus · Apr 27, 2017 · 59372bb · 59372bb
1 parent f832460
commit 59372bb
Showing 1 changed file with 0 additions and 2 deletions.
diff --git a/fs/stat.c b/fs/stat.c
@@ -567,8 +567,6 @@ SYSCALL_DEFINE5(statx,
 		return -EINVAL;
 	if ((flags & AT_STATX_SYNC_TYPE) == AT_STATX_SYNC_TYPE)
 		return -EINVAL;
-	if (!filename)
-		return -EINVAL;
 
 	error = vfs_statx(dfd, filename, flags, &stat, mask);
 	if (error)