From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46B8AC04EBD for ; Tue, 16 Oct 2018 17:23:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0FCF420866 for ; Tue, 16 Oct 2018 17:23:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="as5PFs1r" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0FCF420866 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731428AbeJQBO5 (ORCPT ); Tue, 16 Oct 2018 21:14:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:33448 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730397AbeJQBO4 (ORCPT ); Tue, 16 Oct 2018 21:14:56 -0400 Received: from localhost (ip-213-127-77-176.ip.prioritytelecom.net [213.127.77.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 40E9D20866; Tue, 16 Oct 2018 17:23:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539710610; bh=8VMKZVl1XUnG4zde9geNPLXtx6U+GmWBRA5HkspuBBI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=as5PFs1r5C0ZrKCyt2LQ+wryAiPeCjDiQ1qA6BE1IXGRkSDq1303U7mrdXEuyFg5/ Gb72vvkHYPAb5ZC1Ya5ucNeP/NVIGbP+pIYh3i0n7x+fwENRS4AHsa0BMzzxoP2DqT g9oleLftVU0hKHcJD5rOf1RoZZD0XqjgoznVlRj4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , Willem de Bruijn , syzbot , "David S. Miller" Subject: [PATCH 4.9 26/71] ipv4: fix use-after-free in ip_cmsg_recv_dstaddr() Date: Tue, 16 Oct 2018 19:09:23 +0200 Message-Id: <20181016170540.711499782@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181016170539.315587743@linuxfoundation.org> References: <20181016170539.315587743@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 64199fc0a46ba211362472f7f942f900af9492fd ] Caching ip_hdr(skb) before a call to pskb_may_pull() is buggy, do not do it. Fixes: 2efd4fca703a ("ip: in cmsg IP(V6)_ORIGDSTADDR call pskb_may_pull") Signed-off-by: Eric Dumazet Cc: Willem de Bruijn Reported-by: syzbot Acked-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/ip_sockglue.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -134,7 +134,6 @@ static void ip_cmsg_recv_security(struct static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb) { struct sockaddr_in sin; - const struct iphdr *iph = ip_hdr(skb); __be16 *ports; int end; @@ -149,7 +148,7 @@ static void ip_cmsg_recv_dstaddr(struct ports = (__be16 *)skb_transport_header(skb); sin.sin_family = AF_INET; - sin.sin_addr.s_addr = iph->daddr; + sin.sin_addr.s_addr = ip_hdr(skb)->daddr; sin.sin_port = ports[1]; memset(sin.sin_zero, 0, sizeof(sin.sin_zero));