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=-3.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 59DFDCA9EA0 for ; Fri, 25 Oct 2019 18:07:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 33BFF21D81 for ; Fri, 25 Oct 2019 18:07:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731777AbfJYSHF (ORCPT ); Fri, 25 Oct 2019 14:07:05 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:46884 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731495AbfJYSFo (ORCPT ); Fri, 25 Oct 2019 14:05:44 -0400 Received: from [167.98.27.226] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1iO3xx-0008PC-1x; Fri, 25 Oct 2019 19:05:37 +0100 Received: from ben by deadeye with local (Exim 4.92.2) (envelope-from ) id 1iO3xw-0001kJ-8Y; Fri, 25 Oct 2019 19:05:36 +0100 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, Denis Kirjanov , "Jay Vosburgh" , "Andy Gospodarek" , "David S. Miller" , "Cong Wang" , "Veaceslav Falico" Date: Fri, 25 Oct 2019 19:03:36 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 35/47] bonding: validate ip header before check IPPROTO_IGMP In-Reply-To: X-SA-Exim-Connect-IP: 167.98.27.226 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 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 3.16.76-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Cong Wang commit 9d1bc24b52fb8c5d859f9a47084bf1179470e04c upstream. bond_xmit_roundrobin() checks for IGMP packets but it parses the IP header even before checking skb->protocol. We should validate the IP header with pskb_may_pull() before using iph->protocol. Reported-and-tested-by: syzbot+e5be16aa39ad6e755391@syzkaller.appspotmail.com Fixes: a2fd940f4cff ("bonding: fix broken multicast with round-robin mode") Cc: Jay Vosburgh Cc: Veaceslav Falico Cc: Andy Gospodarek Signed-off-by: Cong Wang Signed-off-by: David S. Miller [bwh: Backported to 3.16: - Keep using ACCESS_ONCE(), dev_kfree_skb_any(), …_can_tx() - Adjust context] Signed-off-by: Ben Hutchings --- drivers/net/bonding/bond_main.c | 37 ++++++++++++++++++++------------- 1 file changed, 23 insertions(+), 14 deletions(-) --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -3700,8 +3700,8 @@ static u32 bond_rr_gen_slave_id(struct b static int bond_xmit_roundrobin(struct sk_buff *skb, struct net_device *bond_dev) { struct bonding *bond = netdev_priv(bond_dev); - struct iphdr *iph = ip_hdr(skb); struct slave *slave; + int slave_cnt; u32 slave_id; /* Start with the curr_active_slave that joined the bond as the @@ -3710,23 +3710,32 @@ static int bond_xmit_roundrobin(struct s * send the join/membership reports. The curr_active_slave found * will send all of this type of traffic. */ - if (iph->protocol == IPPROTO_IGMP && skb->protocol == htons(ETH_P_IP)) { - slave = rcu_dereference(bond->curr_active_slave); - if (slave && bond_slave_can_tx(slave)) - bond_dev_queue_xmit(bond, skb, slave->dev); - else - bond_xmit_slave_id(bond, skb, 0); - } else { - int slave_cnt = ACCESS_ONCE(bond->slave_cnt); + if (skb->protocol == htons(ETH_P_IP)) { + int noff = skb_network_offset(skb); + struct iphdr *iph; + + if (unlikely(!pskb_may_pull(skb, noff + sizeof(*iph)))) + goto non_igmp; - if (likely(slave_cnt)) { - slave_id = bond_rr_gen_slave_id(bond); - bond_xmit_slave_id(bond, skb, slave_id % slave_cnt); - } else { - dev_kfree_skb_any(skb); + iph = ip_hdr(skb); + if (iph->protocol == IPPROTO_IGMP) { + slave = rcu_dereference(bond->curr_active_slave); + if (slave && bond_slave_can_tx(slave)) + bond_dev_queue_xmit(bond, skb, slave->dev); + else + bond_xmit_slave_id(bond, skb, 0); + return NETDEV_TX_OK; } } +non_igmp: + slave_cnt = ACCESS_ONCE(bond->slave_cnt); + if (likely(slave_cnt)) { + slave_id = bond_rr_gen_slave_id(bond); + bond_xmit_slave_id(bond, skb, slave_id % slave_cnt); + } else { + dev_kfree_skb_any(skb); + } return NETDEV_TX_OK; }