From patchwork Sun Apr 7 11:51:56 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mathias Krause X-Patchwork-Id: 234493 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 11A282C00A3 for ; Sun, 7 Apr 2013 21:53:11 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933549Ab3DGLxB (ORCPT ); Sun, 7 Apr 2013 07:53:01 -0400 Received: from mail-bk0-f43.google.com ([209.85.214.43]:36575 "EHLO mail-bk0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933488Ab3DGLwg (ORCPT ); Sun, 7 Apr 2013 07:52:36 -0400 Received: by mail-bk0-f43.google.com with SMTP id jm2so2679693bkc.2 for ; Sun, 07 Apr 2013 04:52:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=20120113; h=x-received:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references; bh=kmqW44dJwUFETszQ+ryaMx5nuJ/rNNLPahLpvDWFVUc=; b=pnlGSGXhP0fivojQNQqLsi5Yp9VH6iKStuC0MUw2t6rXQNTpWYzgXhmj4zi23Kg7wi TIWQ1qMhovi8jaETzC8tUyi9VWAtvLqle0Kdo2kJXo4cb+GXSOez4SejRlga5V9FogAX AWWyM22l5mzhcOwDrZMVtr1GtRPNcPAdOnR/ha+OQQWCfk0FCb6EUtQTbwu5uyNZ2kw+ W0xEQrAW9+z5k8U8oRIYUyGWd2UL11IrF9KzqhpzeJ43sX6/lWQ/ffyqmJnw1qPOaG8s Lm+5FnNk6uJypUnb4doF82kz0Roim02g7C/GVKKcdaKvc+D6qXAcwT1hkOMfSxYy6o6n ycGQ== X-Received: by 10.204.185.70 with SMTP id cn6mr2459541bkb.100.1365335555448; Sun, 07 Apr 2013 04:52:35 -0700 (PDT) Received: from jig.fritz.box (pD9EB4E1C.dip.t-dialin.net. [217.235.78.28]) by mx.google.com with ESMTPS id da16sm1974758bkb.2.2013.04.07.04.52.34 (version=TLSv1.2 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sun, 07 Apr 2013 04:52:34 -0700 (PDT) From: Mathias Krause To: "David S. Miller" Cc: netdev@vger.kernel.org, Allan Stephens , Aloisio Almeida Jr , Andy King , Arnaldo Carvalho de Melo , Dmitry Torokhov , George Zhang , Gustavo Padovan , Johan Hedberg , Jon Maloy , Lauro Ramos Venancio , Marcel Holtmann , Ralf Baechle , Samuel Ortiz , Samuel Ortiz , Sjur Braendeland , Ursula Braun , Brad Spengler , Mathias Krause Subject: [PATCH 10/16] llc: Fix missing msg_namelen update in llc_ui_recvmsg() Date: Sun, 7 Apr 2013 13:51:56 +0200 Message-Id: <1365335522-29931-11-git-send-email-minipli@googlemail.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1365335522-29931-1-git-send-email-minipli@googlemail.com> References: <1365335522-29931-1-git-send-email-minipli@googlemail.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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 --- net/llc/af_llc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c index 8870988..48aaa89 100644 --- a/net/llc/af_llc.c +++ b/net/llc/af_llc.c @@ -720,6 +720,8 @@ static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock, 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))