Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754593Ab3EJOqY (ORCPT ); Fri, 10 May 2013 10:46:24 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:56987 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754419Ab3EJOUU (ORCPT ); Fri, 10 May 2013 10:20:20 -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, "David S. Miller" , "Ralf Baechle" , "Mathias Krause" Date: Fri, 10 May 2013 14:39:41 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [099/118] ax25: fix info leak via msg_name in ax25_recvmsg() In-Reply-To: X-SA-Exim-Connect-IP: 2001:470:1f08:1539:d51a:8785:aa0a:cebe 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 Content-Length: 1555 Lines: 43 3.2.45-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Mathias Krause [ Upstream commit ef3313e84acbf349caecae942ab3ab731471f1a1 ] 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: Ben Hutchings --- net/ax25/af_ax25.c | 1 + 1 file changed, 1 insertion(+) --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -1641,6 +1641,7 @@ static int ax25_recvmsg(struct kiocb *io 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; -- 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/