From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752147Ab3EGOPp (ORCPT ); Tue, 7 May 2013 10:15:45 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:42174 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932598Ab3EGNky (ORCPT ); Tue, 7 May 2013 09:40:54 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Ralf Baechle , Mathias Krause , "David S. Miller" , Luis Henriques Subject: [PATCH 030/118] ax25: fix info leak via msg_name in ax25_recvmsg() Date: Tue, 7 May 2013 14:37:56 +0100 Message-Id: <1367933964-1564-31-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1367933964-1564-1-git-send-email-luis.henriques@canonical.com> References: <1367933964-1564-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.12 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Mathias Krause commit ef3313e84acbf349caecae942ab3ab731471f1a1 upstream. 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 Signed-off-by: Luis Henriques --- 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; -- 1.8.1.2