Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965093AbdCJOIy (ORCPT ); Fri, 10 Mar 2017 09:08:54 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:42688 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933898AbdCJLvV (ORCPT ); Fri, 10 Mar 2017 06:51:21 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Pavel Shilovsky" Date: Fri, 10 Mar 2017 11:46:22 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 073/370] CIFS: Fix a possible memory corruption in push locks In-Reply-To: X-SA-Exim-Connect-IP: 82.70.136.246 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 821 Lines: 28 3.16.42-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Pavel Shilovsky commit e3d240e9d505fc67f8f8735836df97a794bbd946 upstream. If maxBuf is not 0 but less than a size of SMB2 lock structure we can end up with a memory corruption. Signed-off-by: Pavel Shilovsky Signed-off-by: Ben Hutchings --- fs/cifs/smb2file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/cifs/smb2file.c +++ b/fs/cifs/smb2file.c @@ -241,7 +241,7 @@ smb2_push_mandatory_locks(struct cifsFil * and check it for zero before using. */ max_buf = tlink_tcon(cfile->tlink)->ses->server->maxBuf; - if (!max_buf) { + if (max_buf < sizeof(struct smb2_lock_element)) { free_xid(xid); return -EINVAL; }