[PATCH 3.16 187/192] Fix match_prepath()

Ben Hutchings
2017-10-09T14:03:21Z

From: Sachin Prabhu <sprabhu@redhat.com>

commit cd8c42968ee651b69e00f8661caff32b0086e82d upstream.

Incorrect return value for shares not using the prefix path means that
we will never match superblocks for these shares.

Fixes: commit c1d8b24d1819 ("Compare prepaths when comparing superblocks")
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Cc: Aurélien Aptel <aaptel@suse.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
fs/cifs/connect.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)

--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -2756,16 +2756,14 @@ match_prepath(struct super_block *sb, st
{
struct cifs_sb_info *old = CIFS_SB(sb);
struct cifs_sb_info *new = mnt_data->cifs_sb;
+ bool old_set = old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH;
+ bool new_set = new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH;

- if (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) {
- if (!(new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH))
- return 0;
- /* The prepath should be null terminated strings */
- if (strcmp(new->prepath, old->prepath))
- return 0;
-
+ if (old_set && new_set && !strcmp(new->prepath, old->prepath))
+ return 1;
+ else if (!old_set && !new_set)
return 1;
- }
+
return 0;
}