From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756077Ab3FPWXf (ORCPT ); Sun, 16 Jun 2013 18:23:35 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:46412 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755665Ab3FPWIz (ORCPT ); Sun, 16 Jun 2013 18:08:55 -0400 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, "Steve French" , "Jeff Layton" Date: Sun, 16 Jun 2013 23:01:37 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [05/83] cifs: fix potential buffer overrun when composing a new options string In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.101 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 3.2.47-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Jeff Layton commit 166faf21bd14bc5c5295a44874bf7f3930c30b20 upstream. Consider the case where we have a very short ip= string in the original mount options, and when we chase a referral we end up with a very long IPv6 address. Be sure to allow for that possibility when estimating the size of the string to allocate. Signed-off-by: Jeff Layton Signed-off-by: Steve French Signed-off-by: Ben Hutchings --- fs/cifs/cifs_dfs_ref.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/fs/cifs/cifs_dfs_ref.c +++ b/fs/cifs/cifs_dfs_ref.c @@ -18,6 +18,7 @@ #include #include #include +#include #include "cifsglob.h" #include "cifsproto.h" #include "cifsfs.h" @@ -150,7 +151,8 @@ char *cifs_compose_mount_options(const c * assuming that we have 'unc=' and 'ip=' in * the original sb_mountdata */ - md_len = strlen(sb_mountdata) + rc + strlen(ref->node_name) + 12; + md_len = strlen(sb_mountdata) + rc + strlen(ref->node_name) + 12 + + INET6_ADDRSTRLEN; mountdata = kzalloc(md_len+1, GFP_KERNEL); if (mountdata == NULL) { rc = -ENOMEM;