From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-617694-1519837083-2-15169825328343197258 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.249, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='uk', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1519837083; b=ZkjkOOFo0wLScuoHKvuVPsrqZ/ccMon/khSzzDwIAHmmNn7 sdeGuLMKidxncTUsE+appDOTF8axcTt8mTo3TCcGYIr6YpIPYICgSlYR96a2nA66 NfJju3CcU2qJmGhKKiA4DbQspRXJkmO18fQlBh3x1pJc4N2nbqNyZspD7FUOI06N ys3gc//4C4ZdFpkPovvDu3JUu6+KRAPxnkiTp3+PDtE+dtYJsPhh4NRGGKhYY2hP B/004k0Vua7TERLBAFpmJCtkfPyJd7blanP1Q6L+h84jTUEX3rQLOiF+OJI/Hcsz pyZenmp6f8pYGwy3xbwh8Tz0wXDXKXmSWMxvknQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=content-type:content-transfer-encoding :mime-version:from:to:cc:date:message-id:subject:in-reply-to :sender:list-id; s=arctest; t=1519837083; bh=gH6t8KVYdteVhS+25pL 8sOeXR80nnYDEELE5VfXlSls=; b=BqWsjNDQKDnrj7PNEe+vlORWUURBmg357az /m8s8Zv9If/bIzCm1rmUIABvgInY8m+ZKdt18ZgC+iLIhifaQhm10fz2Qgo156zm 3XxkPoP0SBd8lH0wVg78P8exM7DDAxUvLbMCYqi00fWyKkVrNMmBw8zgOLkbcDSZ 0LFUYBgW30pXwC2jtyDbwn6FyShwq6mwQkyLka6ENjid44c+fBSlzN/Foehg8apR DFW2WNjjNaU7B4rPzl1f0H7wSYGxEogg/PYkNDASj4zvs16M4yHZQz2Gg/tuoMMu pcjFs5OcaA18G0oedmcDEn8ouxJEJffac/CY+irT6dhyMmVlVgQ== ARC-Authentication-Results: i=1; mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=decadent.org.uk; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=decadent.org.uk header.result=pass header_is_org_domain=yes Authentication-Results: mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=decadent.org.uk; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=decadent.org.uk header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933927AbeB1Pw7 (ORCPT ); Wed, 28 Feb 2018 10:52:59 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:34423 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932426AbeB1Pw5 (ORCPT ); Wed, 28 Feb 2018 10:52:57 -0500 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, "Mohamed Ghannam" , "David S. Miller" , "Eric Dumazet" Date: Wed, 28 Feb 2018 15:20:18 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 088/254] net: ipv4: fix for a race condition in raw_sendmsg In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 3.16.55-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Mohamed Ghannam commit 8f659a03a0ba9289b9aeb9b4470e6fb263d6f483 upstream. inet->hdrincl is racy, and could lead to uninitialized stack pointer usage, so its value should be read only once. Fixes: c008ba5bdc9f ("ipv4: Avoid reading user iov twice after raw_probe_proto_opt") Signed-off-by: Mohamed Ghannam Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- net/ipv4/raw.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -490,11 +490,16 @@ static int raw_sendmsg(struct kiocb *ioc int err; struct ip_options_data opt_copy; struct raw_frag_vec rfv; + int hdrincl; err = -EMSGSIZE; if (len > 0xFFFF) goto out; + /* hdrincl should be READ_ONCE(inet->hdrincl) + * but READ_ONCE() doesn't work with bit fields + */ + hdrincl = inet->hdrincl; /* * Check the flags. */ @@ -569,7 +574,7 @@ static int raw_sendmsg(struct kiocb *ioc /* Linux does not mangle headers on raw sockets, * so that IP options + IP_HDRINCL is non-sense. */ - if (inet->hdrincl) + if (hdrincl) goto done; if (ipc.opt->opt.srr) { if (!daddr) @@ -591,12 +596,12 @@ static int raw_sendmsg(struct kiocb *ioc flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos, RT_SCOPE_UNIVERSE, - inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol, + hdrincl ? IPPROTO_RAW : sk->sk_protocol, inet_sk_flowi_flags(sk) | - (inet->hdrincl ? FLOWI_FLAG_KNOWN_NH : 0), + (hdrincl ? FLOWI_FLAG_KNOWN_NH : 0), daddr, saddr, 0, 0); - if (!inet->hdrincl) { + if (!hdrincl) { rfv.iov = msg->msg_iov; rfv.hlen = 0; @@ -621,7 +626,7 @@ static int raw_sendmsg(struct kiocb *ioc goto do_confirm; back_from_confirm: - if (inet->hdrincl) + if (hdrincl) err = raw_send_hdrinc(sk, &fl4, msg->msg_iov, len, &rt, msg->msg_flags);