From patchwork Tue Sep 13 13:24:02 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Whitcroft X-Patchwork-Id: 114491 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from chlorine.canonical.com (chlorine.canonical.com [91.189.94.204]) by ozlabs.org (Postfix) with ESMTP id C1C40B71C2 for ; Tue, 13 Sep 2011 23:24:50 +1000 (EST) Received: from localhost ([127.0.0.1] helo=chlorine.canonical.com) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1R3SyN-0002u2-Fb; Tue, 13 Sep 2011 13:24:23 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1R3Sy5-0002qX-W7 for kernel-team@lists.ubuntu.com; Tue, 13 Sep 2011 13:24:06 +0000 Received: from 212-139-214-120.dynamic.dsl.as9105.com ([212.139.214.120] helo=localhost.localdomain) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1R3Sy5-0005cP-SU; Tue, 13 Sep 2011 13:24:05 +0000 From: Andy Whitcroft To: kernel-team@lists.ubuntu.com Subject: [maverick, maverick/ti-omap4, natty, natty/ti-omap4, oneiric, oneiric/ti-omap4 CVE 1/1] cifs: fix possible memory corruption in CIFSFindNext Date: Tue, 13 Sep 2011 14:24:02 +0100 Message-Id: <1315920242-8819-4-git-send-email-apw@canonical.com> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1315920242-8819-1-git-send-email-apw@canonical.com> References: <1315920242-8819-1-git-send-email-apw@canonical.com> Cc: Andy Whitcroft X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.13 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: kernel-team-bounces@lists.ubuntu.com Errors-To: kernel-team-bounces@lists.ubuntu.com From: Jeff Layton The name_len variable in CIFSFindNext is a signed int that gets set to the resume_name_len in the cifs_search_info. The resume_name_len however is unsigned and for some infolevels is populated directly from a 32 bit value sent by the server. If the server sends a very large value for this, then that value could look negative when converted to a signed int. That would make that value pass the PATH_MAX check later in CIFSFindNext. The name_len would then be used as a length value for a memcpy. It would then be treated as unsigned again, and the memcpy scribbles over a ton of memory. Fix this by making the name_len an unsigned value in CIFSFindNext. Cc: Reported-by: Darren Lavender Signed-off-by: Jeff Layton Signed-off-by: Steve French Signed-off-by: Suresh Jayaraman (cherry-picked from commit c32dfffaf59f73bbcf4472141b851a4dc5db2bf0 cifs-2.6.git) CVE-2011-3191 BugLink: http://bugs.launchpad.net/bugs/834135 Signed-off-by: Andy Whitcroft --- fs/cifs/cifssmb.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index 6b764d7..df299c1 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -3748,7 +3748,8 @@ int CIFSFindNext(const int xid, struct cifsTconInfo *tcon, T2_FNEXT_RSP_PARMS *parms; char *response_data; int rc = 0; - int bytes_returned, name_len; + int bytes_returned; + unsigned int name_len; __u16 params, byte_count; cFYI(1, "In FindNext");