cifs: avoid NULL pointer dereference in dbg call

commit b4885bd5935bb26f0a414ad55679a372e53f9b9b upstream.

cifs_server_dbg() implies server to be non-NULL so
move call under condition to avoid NULL pointer dereference.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: e79b0332ae06 ("cifs: ignore cached share root handle closing errors")
Cc: stable@vger.kernel.org
Signed-off-by: Alexandra Diupina <adiupina@astralinux.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/smb/client/smb2misc.c b/fs/smb/client/smb2misc.c
index f3c4b70b77b94f3797362ecc0fdb32608f87aea5..cddf273c14aed70d60e2c10d7d4bdc541260bcff 100644 (file)
--- a/fs/smb/client/smb2misc.c
+++ b/fs/smb/client/smb2misc.c
@@ -816,11 +816,12 @@ smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
                WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
                spin_unlock(&cifs_tcp_ses_lock);
 
-               if (tcon->ses)
+               if (tcon->ses) {
                        server = tcon->ses->server;
-
-               cifs_server_dbg(FYI, "tid=0x%x: tcon is closing, skipping async close retry of fid %llu %llu\n",
-                               tcon->tid, persistent_fid, volatile_fid);
+                       cifs_server_dbg(FYI,
+                                       "tid=0x%x: tcon is closing, skipping async close retry of fid %llu %llu\n",
+                                       tcon->tid, persistent_fid, volatile_fid);
+               }
 
                return 0;
        }