smb/server: Fix another refcount leak in smb2_open()

If ksmbd_override_fsids() fails, we jump to err_out2. At that point, fp is
NULL because it hasn't been assigned dh_info.fp yet, so ksmbd_fd_put(work,
fp) will not be called. However, dh_info.fp was already inserted into the
session file table by ksmbd_reopen_durable_fd(), so it will leak in the
session file table until the session is closed.

Move fp = dh_info.fp; ahead of the ksmbd_override_fsids() check to fix the
problem.

Found by an experimental AI code review agent at Google.

Fixes: c8efcc7 ("ksmbd: add support for durable handles v1/v2")
Signed-off-by: Guenter Roeck <[email protected]>
Reviewed-by: ChenXiaoSong <[email protected]>
Acked-by: Namjae Jeon <[email protected]>
Signed-off-by: Steve French <[email protected]>

Author: groeck

fs/smb/server/smb2pdu.c

@@ -3012,13 +3012,14 @@ int smb2_open(struct ksmbd_work *work)
 				goto err_out2;
 			}
 
+			fp = dh_info.fp;
+
 			if (ksmbd_override_fsids(work)) {
 				rc = -ENOMEM;
 				ksmbd_put_durable_fd(dh_info.fp);
 				goto err_out2;
 			}
 
-			fp = dh_info.fp;
 			file_info = FILE_OPENED;
 
 			rc = ksmbd_vfs_getattr(&fp->filp->f_path, &stat);