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=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED,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 22BF6C072B1 for ; Thu, 30 May 2019 03:58:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EB6B624F10 for ; Thu, 30 May 2019 03:58:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559188726; bh=tDB5YY0NPcT0l/Ix8REcVlx+WJ/4cDK4koo2CQwZI9s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=UWnjywXT8+NaehJNMpoE6dbNzifvps2mGIuSQFZcf8ML4de8Fppi37p+K+H5JJaEi W40VUUv21w/q3XKgTciubt+RIH6zuzTotA75/2MwY2WXjWwuE7NQQZY+QPVfgLShFU qmvn8DgDBdPUQBxpuRq/mvqKvxGNGGfjV3nuzbFc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732453AbfE3D6p (ORCPT ); Wed, 29 May 2019 23:58:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:52258 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730213AbfE3DSn (ORCPT ); Wed, 29 May 2019 23:18:43 -0400 Received: from localhost (ip67-88-213-2.z213-88-67.customer.algx.net [67.88.213.2]) (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 959DF2475F; Thu, 30 May 2019 03:18:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559186322; bh=tDB5YY0NPcT0l/Ix8REcVlx+WJ/4cDK4koo2CQwZI9s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DXj1mQfxDKKIQnSK4NIcYqTfb483F9S64qhmmmVPi2NTJZX2THFEchOsYDKS5iP1A 83kYDZpgKpmsvVkikVious7Up2N3L48sSFCTziD7FW21iR/1Kc/lQJ/lLI8qRdpE6p OBVM6rVx2tLBG9mmwsxoj88e6aP2n12m+uVOa5Qk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+9723f2d288e49b492cf0@syzkaller.appspotmail.com, syzbot+f0ddeb2b032a8e1d9098@syzkaller.appspotmail.com, syzbot+f14b3703cd8d7670203f@syzkaller.appspotmail.com, syzbot+eefa384efad8d7997f20@syzkaller.appspotmail.com, William Tu , "David S. Miller" , Christoph Paasch Subject: [PATCH 4.14 034/193] net: erspan: fix use-after-free Date: Wed, 29 May 2019 20:04:48 -0700 Message-Id: <20190530030454.006155866@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190530030446.953835040@linuxfoundation.org> References: <20190530030446.953835040@linuxfoundation.org> User-Agent: quilt/0.66 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 From: William Tu commit b423d13c08a656c719fa56324a8f4279c835d90c upstream. When building the erspan header for either v1 or v2, the eth_hdr() does not point to the right inner packet's eth_hdr, causing kasan report use-after-free and slab-out-of-bouds read. The patch fixes the following syzkaller issues: [1] BUG: KASAN: slab-out-of-bounds in erspan_xmit+0x22d4/0x2430 net/ipv4/ip_gre.c:735 [2] BUG: KASAN: slab-out-of-bounds in erspan_build_header+0x3bf/0x3d0 net/ipv4/ip_gre.c:698 [3] BUG: KASAN: use-after-free in erspan_xmit+0x22d4/0x2430 net/ipv4/ip_gre.c:735 [4] BUG: KASAN: use-after-free in erspan_build_header+0x3bf/0x3d0 net/ipv4/ip_gre.c:698 [2] CPU: 0 PID: 3654 Comm: syzkaller377964 Not tainted 4.15.0-rc9+ #185 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:440 erspan_build_header+0x3bf/0x3d0 net/ipv4/ip_gre.c:698 erspan_xmit+0x3b8/0x13b0 net/ipv4/ip_gre.c:740 __netdev_start_xmit include/linux/netdevice.h:4042 [inline] netdev_start_xmit include/linux/netdevice.h:4051 [inline] packet_direct_xmit+0x315/0x6b0 net/packet/af_packet.c:266 packet_snd net/packet/af_packet.c:2943 [inline] packet_sendmsg+0x3aed/0x60b0 net/packet/af_packet.c:2968 sock_sendmsg_nosec net/socket.c:638 [inline] sock_sendmsg+0xca/0x110 net/socket.c:648 SYSC_sendto+0x361/0x5c0 net/socket.c:1729 SyS_sendto+0x40/0x50 net/socket.c:1697 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline] do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129 RIP: 0023:0xf7fcfc79 RSP: 002b:00000000ffc6976c EFLAGS: 00000286 ORIG_RAX: 0000000000000171 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000020011000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020008000 RBP: 000000000000001c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Fixes: f551c91de262 ("net: erspan: introduce erspan v2 for ip_gre") Fixes: 84e54fe0a5ea ("gre: introduce native tunnel support for ERSPAN") Reported-by: syzbot+9723f2d288e49b492cf0@syzkaller.appspotmail.com Reported-by: syzbot+f0ddeb2b032a8e1d9098@syzkaller.appspotmail.com Reported-by: syzbot+f14b3703cd8d7670203f@syzkaller.appspotmail.com Reported-by: syzbot+eefa384efad8d7997f20@syzkaller.appspotmail.com Signed-off-by: William Tu Signed-off-by: David S. Miller Signed-off-by: Christoph Paasch Signed-off-by: Greg Kroah-Hartman --- net/ipv4/ip_gre.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -689,7 +689,7 @@ static void erspan_build_header(struct s __be32 id, u32 index, bool truncate) { struct iphdr *iphdr = ip_hdr(skb); - struct ethhdr *eth = eth_hdr(skb); + struct ethhdr *eth = (struct ethhdr *)skb->data; enum erspan_encap_type enc_type; struct erspanhdr *ershdr; struct qtag_prefix {