Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754635Ab3EJOsi (ORCPT ); Fri, 10 May 2013 10:48:38 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:56929 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754247Ab3EJOUJ (ORCPT ); Fri, 10 May 2013 10:20:09 -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, "Arnaldo Carvalho de Melo" , "David S. Miller" , "Mathias Krause" Date: Fri, 10 May 2013 14:39:41 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [105/118] llc: Fix missing msg_namelen update in llc_ui_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: 1486 Lines: 42 3.2.45-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Mathias Krause [ Upstream commit c77a4b9cffb6215a15196ec499490d116dfad181 ] For stream sockets the code misses to update the msg_namelen member to 0 and therefore makes net/socket.c leak the local, uninitialized sockaddr_storage variable to userland -- 128 bytes of kernel stack memory. The msg_namelen update is also missing for datagram sockets in case the socket is shutting down during receive. Fix both issues by setting msg_namelen to 0 early. It will be updated later if we're going to fill the msg_name member. Cc: Arnaldo Carvalho de Melo Signed-off-by: Mathias Krause Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/llc/af_llc.c | 2 ++ 1 file changed, 2 insertions(+) --- a/net/llc/af_llc.c +++ b/net/llc/af_llc.c @@ -720,6 +720,8 @@ static int llc_ui_recvmsg(struct kiocb * int target; /* Read at least this many bytes */ long timeo; + msg->msg_namelen = 0; + lock_sock(sk); copied = -ENOTCONN; if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN)) -- 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/