From patchwork Wed Jul 10 13:40:10 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 1130402 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.b="Td7S4Xt8"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 45kL0k2Ctmz9s4Y for ; Wed, 10 Jul 2019 23:40:22 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727628AbfGJNkV (ORCPT ); Wed, 10 Jul 2019 09:40:21 -0400 Received: from mail-vk1-f202.google.com ([209.85.221.202]:49144 "EHLO mail-vk1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726080AbfGJNkV (ORCPT ); Wed, 10 Jul 2019 09:40:21 -0400 Received: by mail-vk1-f202.google.com with SMTP id f184so1037312vkd.15 for ; Wed, 10 Jul 2019 06:40:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=sWNQV8EzHYlsVIIy/bLdc0fwuJnJIg+j+AHcE+ofiXw=; b=Td7S4Xt8u8zPgolaIIniLnTVLTo3DTiaI34mpKqZac51fybarT8G0wT7WbpCeZyWRN fvQY1/BjexABXPWxBPh/F58OzdmKBUFE3+SbSQLrEgn1LfsYi7Eg5Xqr4TJ3XVTXzyge KRMxpDRD8S8zhJiKeQZq2LyY4TQaFoCUfeJcWYcIpZ8TGFAnNcU7AaEUce9kpd5T6OS6 XIBG9Ydx4HkLd2F8BnTmzdpUObwwkIl/D7n/Hja/JyV8NRQ8DFXBFyQTXphYxaciaAHA rGUNI4SntsSTZzSwEm16bdpogpaeuThuwpqpOtib4eUMXtcOUaHhejtwV3BiLJRjWSGz CU8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=sWNQV8EzHYlsVIIy/bLdc0fwuJnJIg+j+AHcE+ofiXw=; b=QPNtR6h8G/ZzIV24KwHJMtv64+l5sNr0ELL13VRA1ZV47KHLiP9tXwQQ0Yi3Rdw1tD WE08sUtCxKg6yjKz/PQHJdY0MczhoKDSw1K8Xm4J3gIQUyXiRdj/K2fH1k964Zp+Nc4v M5i0ZYGLJHgCds+ZhH7dyNFopCDJPe4zYToOdhcyt+NqjOh8WCwZA04cm+AksT/KUUSM aB5+XSfjGDbRwsF3r4Z7I7dkhqhtTxL6CZHU96Ua+uDTpibC1BtViNMoCAxyAPhb6AEb H8i4asNHGmazoWA2wmpi8wuU8aA6brmuSNBNj9JVS8efreHUCAmQZr+c+LsWs/90GM0z R23w== X-Gm-Message-State: APjAAAU6ORjXgxC8Eb1buXek4nNrd3kFLCoUsQEpzMCjuh/MnfeYuJ4y 9YGxWhzhVw48DKQWqY67elsaOvbC+1dDCQ== X-Google-Smtp-Source: APXvYqwCKnlmSFD7gAokfkPT+8aNqk1ZpzCJUNyajGPAhzZXWpkTophW2sY2UK1Rxp0qwv6Uj5tVFh6e4bjP3g== X-Received: by 2002:ab0:2650:: with SMTP id q16mr17608714uao.7.1562766019866; Wed, 10 Jul 2019 06:40:19 -0700 (PDT) Date: Wed, 10 Jul 2019 06:40:10 -0700 In-Reply-To: <20190710134011.221210-1-edumazet@google.com> Message-Id: <20190710134011.221210-2-edumazet@google.com> Mime-Version: 1.0 References: <20190710134011.221210-1-edumazet@google.com> X-Mailer: git-send-email 2.22.0.410.gd8fdbe21b5-goog Subject: [PATCH net] ipv6: fix potential crash in ip6_datagram_dst_update() From: Eric Dumazet To: "David S . Miller" Cc: netdev , Eric Dumazet , Eric Dumazet , Willem de Bruijn , syzbot Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Willem forgot to change one of the calls to fl6_sock_lookup(), which can now return an error or NULL. syzbot reported : kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 31763 Comm: syz-executor.0 Not tainted 5.2.0-rc6+ #63 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:ip6_datagram_dst_update+0x559/0xc30 net/ipv6/datagram.c:83 Code: 00 00 e8 ea 29 3f fb 4d 85 f6 0f 84 96 04 00 00 e8 dc 29 3f fb 49 8d 7e 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 16 06 00 00 4d 8b 6e 20 e8 b4 29 3f fb 4c 89 ee RSP: 0018:ffff88809ba97ae0 EFLAGS: 00010207 RAX: dffffc0000000000 RBX: ffff8880a81254b0 RCX: ffffc90008118000 RDX: 0000000000000003 RSI: ffffffff86319a84 RDI: 000000000000001e RBP: ffff88809ba97c10 R08: ffff888065e9e700 R09: ffffed1015d26c80 R10: ffffed1015d26c7f R11: ffff8880ae9363fb R12: ffff8880a8124f40 R13: 0000000000000001 R14: fffffffffffffffe R15: ffff88809ba97b40 FS: 00007f38e606a700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000202c0140 CR3: 00000000a026a000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __ip6_datagram_connect+0x5e9/0x1390 net/ipv6/datagram.c:246 ip6_datagram_connect+0x30/0x50 net/ipv6/datagram.c:269 ip6_datagram_connect_v6_only+0x69/0x90 net/ipv6/datagram.c:281 inet_dgram_connect+0x14a/0x2d0 net/ipv4/af_inet.c:571 __sys_connect+0x264/0x330 net/socket.c:1824 __do_sys_connect net/socket.c:1835 [inline] __se_sys_connect net/socket.c:1832 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1832 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4597c9 Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f38e6069c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004597c9 RDX: 000000000000001c RSI: 0000000020000040 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f38e606a6d4 R13: 00000000004bfd07 R14: 00000000004d1838 R15: 00000000ffffffff Modules linked in: RIP: 0010:ip6_datagram_dst_update+0x559/0xc30 net/ipv6/datagram.c:83 Code: 00 00 e8 ea 29 3f fb 4d 85 f6 0f 84 96 04 00 00 e8 dc 29 3f fb 49 8d 7e 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 16 06 00 00 4d 8b 6e 20 e8 b4 29 3f fb 4c 89 ee Fixes: 59c820b2317f ("ipv6: elide flowlabel check if no exclusive leases exist") Signed-off-by: Eric Dumazet Acked-by: Willem de Bruijn Reported-by: syzbot --- net/ipv6/datagram.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c index 9d78c907b918a98cbb9e80154a038e31b6bddd11..9ab897ded4df52d882cda1414ef0159f3eb1765a 100644 --- a/net/ipv6/datagram.c +++ b/net/ipv6/datagram.c @@ -74,7 +74,7 @@ int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr) if (np->sndflow && (np->flow_label & IPV6_FLOWLABEL_MASK)) { flowlabel = fl6_sock_lookup(sk, np->flow_label); - if (!flowlabel) + if (IS_ERR(flowlabel)) return -EINVAL; } ip6_datagram_flow_key_init(&fl6, sk);