[PATCH 4.11 082/197] Make stat/lstat/fstatat pass AT_NO_AUTOMOUNT to vfs_statx()

[Greg Kroah-Hartman]

4.11-stable review patch.  If anyone has any objections, please let me know.

------------------

From: David Howells <dhowells@xxxxxxxxxx>

commit deccf497d804a4c5fca2dbfad2f104675a6f9102 upstream.

stat/lstat/fstatat need to pass AT_NO_AUTOMOUNT to vfs_statx() as the
pre-statx code didn't set LOOKUP_AUTOMOUNT, even though fstatat() accepted
the AT_NO_AUTOMOUNT flag.

Fixes: a528d35e8bfc ("statx: Add a system call to make enhanced file info available")
Reported-by: Ian Kent <raven@xxxxxxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Tested-by: Ian Kent <raven@xxxxxxxxxx>
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 include/linux/fs.h |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2921,17 +2921,19 @@ extern int vfs_statx_fd(unsigned int, st
 
 static inline int vfs_stat(const char __user *filename, struct kstat *stat)
 {
-	return vfs_statx(AT_FDCWD, filename, 0, stat, STATX_BASIC_STATS);
+	return vfs_statx(AT_FDCWD, filename, AT_NO_AUTOMOUNT,
+			 stat, STATX_BASIC_STATS);
 }
 static inline int vfs_lstat(const char __user *name, struct kstat *stat)
 {
-	return vfs_statx(AT_FDCWD, name, AT_SYMLINK_NOFOLLOW,
+	return vfs_statx(AT_FDCWD, name, AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT,
 			 stat, STATX_BASIC_STATS);
 }
 static inline int vfs_fstatat(int dfd, const char __user *filename,
 			      struct kstat *stat, int flags)
 {
-	return vfs_statx(dfd, filename, flags, stat, STATX_BASIC_STATS);
+	return vfs_statx(dfd, filename, flags | AT_NO_AUTOMOUNT,
+			 stat, STATX_BASIC_STATS);
 }
 static inline int vfs_fstat(int fd, struct kstat *stat)
 {