Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755619AbaBEVLl (ORCPT ); Wed, 5 Feb 2014 16:11:41 -0500 Received: from mail1.windriver.com ([147.11.146.13]:47948 "EHLO mail1.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754006AbaBEUD4 (ORCPT ); Wed, 5 Feb 2014 15:03:56 -0500 From: Paul Gortmaker To: , CC: Mathias Krause , Ralf Baechle , "David S. Miller" , Paul Gortmaker Subject: [v2.6.34-stable 028/213] ax25: fix info leak via msg_name in ax25_recvmsg() Date: Wed, 5 Feb 2014 14:59:43 -0500 Message-ID: <1391630568-49251-29-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1391630568-49251-1-git-send-email-paul.gortmaker@windriver.com> References: <1391630568-49251-1-git-send-email-paul.gortmaker@windriver.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mathias Krause ------------------- This is a commit scheduled for the next v2.6.34 longterm release. http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git If you see a problem with using this for longterm, please comment. ------------------- 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: Paul Gortmaker --- 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 12c350c63717..d082b6db6b81 100644 --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -1655,6 +1655,7 @@ 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; -- 1.8.5.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/