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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 BB8A7C1B0D8 for ; Sun, 6 Dec 2020 11:42:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 94DD02313F for ; Sun, 6 Dec 2020 11:42:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728932AbgLFLmY (ORCPT ); Sun, 6 Dec 2020 06:42:24 -0500 Received: from mail.kernel.org ([198.145.29.99]:39826 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728950AbgLFLmR (ORCPT ); Sun, 6 Dec 2020 06:42:17 -0500 From: Greg Kroah-Hartman Authentication-Results: mail.kernel.org; dkim=permerror (bad message/signature format) To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , syzbot , Jakub Kicinski Subject: [PATCH 5.4 22/39] geneve: pull IP header before ECN decapsulation Date: Sun, 6 Dec 2020 12:17:26 +0100 Message-Id: <20201206111555.740127116@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201206111554.677764505@linuxfoundation.org> References: <20201206111554.677764505@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Dumazet [ Upstream commit 4179b00c04d18ea7013f68d578d80f3c9d13150a ] IP_ECN_decapsulate() and IP6_ECN_decapsulate() assume IP header is already pulled. geneve does not ensure this yet. Fixing this generically in IP_ECN_decapsulate() and IP6_ECN_decapsulate() is not possible, since callers pass a pointer that might be freed by pskb_may_pull() syzbot reported : BUG: KMSAN: uninit-value in __INET_ECN_decapsulate include/net/inet_ecn.h:238 [inline] BUG: KMSAN: uninit-value in INET_ECN_decapsulate+0x345/0x1db0 include/net/inet_ecn.h:260 CPU: 1 PID: 8941 Comm: syz-executor.0 Not tainted 5.10.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x21c/0x280 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:197 __INET_ECN_decapsulate include/net/inet_ecn.h:238 [inline] INET_ECN_decapsulate+0x345/0x1db0 include/net/inet_ecn.h:260 geneve_rx+0x2103/0x2980 include/net/inet_ecn.h:306 geneve_udp_encap_recv+0x105c/0x1340 drivers/net/geneve.c:377 udp_queue_rcv_one_skb+0x193a/0x1af0 net/ipv4/udp.c:2093 udp_queue_rcv_skb+0x282/0x1050 net/ipv4/udp.c:2167 udp_unicast_rcv_skb net/ipv4/udp.c:2325 [inline] __udp4_lib_rcv+0x399d/0x5880 net/ipv4/udp.c:2394 udp_rcv+0x5c/0x70 net/ipv4/udp.c:2564 ip_protocol_deliver_rcu+0x572/0xc50 net/ipv4/ip_input.c:204 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_local_deliver+0x583/0x8d0 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:449 [inline] ip_rcv_finish net/ipv4/ip_input.c:428 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_rcv+0x5c3/0x840 net/ipv4/ip_input.c:539 __netif_receive_skb_one_core net/core/dev.c:5315 [inline] __netif_receive_skb+0x1ec/0x640 net/core/dev.c:5429 process_backlog+0x523/0xc10 net/core/dev.c:6319 napi_poll+0x420/0x1010 net/core/dev.c:6763 net_rx_action+0x35c/0xd40 net/core/dev.c:6833 __do_softirq+0x1a9/0x6fa kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x6e/0x90 arch/x86/kernel/irq_64.c:77 do_softirq kernel/softirq.c:343 [inline] __local_bh_enable_ip+0x184/0x1d0 kernel/softirq.c:195 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32 rcu_read_unlock_bh include/linux/rcupdate.h:730 [inline] __dev_queue_xmit+0x3a9b/0x4520 net/core/dev.c:4167 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4173 packet_snd net/packet/af_packet.c:2992 [inline] packet_sendmsg+0x86f9/0x99d0 net/packet/af_packet.c:3017 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg net/socket.c:671 [inline] __sys_sendto+0x9dc/0xc80 net/socket.c:1992 __do_sys_sendto net/socket.c:2004 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:2000 __x64_sys_sendto+0x6e/0x90 net/socket.c:2000 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 2d07dc79fe04 ("geneve: add initial netdev driver for GENEVE tunnels") Signed-off-by: Eric Dumazet Reported-by: syzbot Link: https://lore.kernel.org/r/20201201090507.4137906-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/geneve.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -254,11 +254,21 @@ static void geneve_rx(struct geneve_dev skb_dst_set(skb, &tun_dst->dst); /* Ignore packet loops (and multicast echo) */ - if (ether_addr_equal(eth_hdr(skb)->h_source, geneve->dev->dev_addr)) { - geneve->dev->stats.rx_errors++; - goto drop; - } + if (ether_addr_equal(eth_hdr(skb)->h_source, geneve->dev->dev_addr)) + goto rx_error; + switch (skb_protocol(skb, true)) { + case htons(ETH_P_IP): + if (pskb_may_pull(skb, sizeof(struct iphdr))) + goto rx_error; + break; + case htons(ETH_P_IPV6): + if (pskb_may_pull(skb, sizeof(struct ipv6hdr))) + goto rx_error; + break; + default: + goto rx_error; + } oiph = skb_network_header(skb); skb_reset_network_header(skb); @@ -299,6 +309,8 @@ static void geneve_rx(struct geneve_dev u64_stats_update_end(&stats->syncp); } return; +rx_error: + geneve->dev->stats.rx_errors++; drop: /* Consume bad packet */ kfree_skb(skb);