From patchwork Thu May 9 10:01:48 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 242743 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id AD0192C00EB for ; Thu, 9 May 2013 20:02:00 +1000 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1UaNff-0000Da-BY; Thu, 09 May 2013 10:01:55 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1UaNfZ-00007f-4a for kernel-team@lists.ubuntu.com; Thu, 09 May 2013 10:01:49 +0000 Received: from bl16-212-84.dsl.telepac.pt ([188.81.212.84] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1UaNfY-0001eL-VA for kernel-team@lists.ubuntu.com; Thu, 09 May 2013 10:01:49 +0000 From: Luis Henriques To: kernel-team@lists.ubuntu.com Subject: [Lucid Precise Quantal CVE-2013-3223] ax25: fix info leak via msg_name in ax25_recvmsg() Date: Thu, 9 May 2013 11:01:48 +0100 Message-Id: <1368093708-6724-1-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.1.2 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com From: Mathias Krause CVE-2013-3223 BugLink: https://bugs.launchpad.net/bugs/1172366 When msg_namelen is non-zero the sockaddr info gets filled out, as requested, but the code fails to initialize the padding bytes of struct sockaddr_ax25 inserted by the compiler for alignment. Additionally the msg_namelen value is updated to sizeof(struct full_sockaddr_ax25) but is not always filled up to this size. Both issues lead to the fact that the code will leak uninitialized kernel stack bytes in net/socket.c. Fix both issues by initializing the memory with memset(0). Cc: Ralf Baechle Signed-off-by: Mathias Krause Signed-off-by: David S. Miller (cherry picked from commit ef3313e84acbf349caecae942ab3ab731471f1a1) Signed-off-by: Luis Henriques Acked-by: Andy Whitcroft --- net/ax25/af_ax25.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c index 779095d..d53a123 100644 --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -1647,6 +1647,7 @@ static int ax25_recvmsg(struct kiocb *iocb, struct socket *sock, ax25_address src; const unsigned char *mac = skb_mac_header(skb); + memset(sax, 0, sizeof(struct full_sockaddr_ax25)); ax25_addr_parse(mac + 1, skb->data - mac - 1, &src, NULL, &digi, NULL, NULL); sax->sax25_family = AF_AX25;