ksmbd: fix bug on trap in smb2_lock

commit e26e2d2e15daf1ab33e0135caf2304a0cfa2744b upstream.

If lock count is greater than 1, flags could be old value.
It should be checked with flags of smb_lock, not flags.
It will cause bug-on trap from locks_free_lock in error handling
routine.

Cc: stable@vger.kernel.org
Reported-by: Norbert Szetei <norbert@doyensec.com>
Tested-by: Norbert Szetei <norbert@doyensec.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c
index c69be6931e977c3b0404f3d37b62f3927cb7019b..8464261d763876c14d39dbb6f9e917ce69ce4de7 100644 (file)
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -7451,7 +7451,7 @@ no_check_cl:
 retry:
                rc = vfs_lock_file(filp, smb_lock->cmd, flock, NULL);
 skip:
-               if (flags & SMB2_LOCKFLAG_UNLOCK) {
+               if (smb_lock->flags & SMB2_LOCKFLAG_UNLOCK) {
                        if (!rc) {
                                ksmbd_debug(SMB, "File unlocked\n");
                        } else if (rc == -ENOENT) {