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=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 DC5B9C3A5A2 for ; Fri, 23 Aug 2019 10:27:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A6CC222CEC for ; Fri, 23 Aug 2019 10:27:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="SiOv64lM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390404AbfHWK07 (ORCPT ); Fri, 23 Aug 2019 06:26:59 -0400 Received: from mail-wm1-f67.google.com ([209.85.128.67]:33612 "EHLO mail-wm1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731002AbfHWK07 (ORCPT ); Fri, 23 Aug 2019 06:26:59 -0400 Received: by mail-wm1-f67.google.com with SMTP id p77so8995390wme.0; Fri, 23 Aug 2019 03:26:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=9luq02UH+TFnlClChMvpFV6YHyNnbxJC+jcjQiDKx2M=; b=SiOv64lM6z/RgsZG905NKePuL1c3HgnTz6LfkZbs1Z4QVR6+hKt6gR/4tVts4ylzeb NWOko9uC+ACPn6gjeTirU/OuxBp9pKGLV5Yysbbo61TIP2ulG8QPFO3OrDuT2PRl2UUR rommm4CGvyhfVhLEBu0Iw+h99uPRzUsb9ajsjxgRbJ2huFlDXTZuRVhUzUS1Dne8OPtv +5BY5z0FujGYiAIMUlDyW/TfbMzqGTU0gDyQJBTDGQkM3MmmPLV5D9kjTwkclEZvSUU7 eZmBKAgKir0H1eBkOXuqRIlT7OXAWFa1jl2g3wcdeNRwRsvaFo2UpcngJ66QQaqxifWj 3QYg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=9luq02UH+TFnlClChMvpFV6YHyNnbxJC+jcjQiDKx2M=; b=hCzdwBaxdxXgiMR5aj6lmCPZ4bShxZoRm2LlRBdCzBl6Suq1kvvPv0bmLPMa/mE79C TFjWBAVa0TY8uCOqlCXZlNGBBkpsTIOgzYNQ915+fOlGbma8JbDN+JyJTISKh6C/sA/G F9DQ3paVDCwk3wtxaTJC6NB/QDIBSNdytqUtdRgz8rlTRaYX6BP1C7/yX3Z4ym1sTWh9 BQt34U3NrY+ztLb9spox18eBHIVypCpD+oA1wWpeVEu6ldfzfl2GtbGVKxIleLJmeLKC M0RqzQOtwoNShYo4ZglEKlavrucZBm5TU3bqgX4i1v6f3bRFH+n8Yc+ah8vlsSNxLce1 1cCw== X-Gm-Message-State: APjAAAWVMywE8t4pQMToB56Tom8sOkwDwWq2+5nBE2SIUe+HHYiPdefN fuNupODzryZzXN6UTUxcglviZI394/q8FARqFaA= X-Google-Smtp-Source: APXvYqxlyz4RncFg5/k3Xmj8V6bvDiCd0k6CEtn82mX40vUXTidncUq4tSbHlp5i38zXEVBSfbnfMDA3GykWxLzPoFc= X-Received: by 2002:a1c:6385:: with SMTP id x127mr4366246wmb.140.1566556015899; Fri, 23 Aug 2019 03:26:55 -0700 (PDT) MIME-Version: 1.0 References: <0000000000008182a50590404a02@google.com> In-Reply-To: From: Xin Long Date: Fri, 23 Aug 2019 18:26:44 +0800 Message-ID: Subject: Re: kernel BUG at include/linux/skbuff.h:LINE! (2) To: Dmitry Vyukov Cc: syzbot , davem , LKML , linux-sctp@vger.kernel.org, Marcelo Ricardo Leitner , network dev , Neil Horman , syzkaller-bugs , Vlad Yasevich Content-Type: text/plain; charset="UTF-8" Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, Aug 19, 2019 at 10:44 PM Xin Long wrote: > > On Sun, Aug 18, 2019 at 10:13 PM Dmitry Vyukov wrote: > > > > On Sun, Aug 18, 2019 at 7:07 AM Xin Long wrote: > > > > > > On Sat, Aug 17, 2019 at 2:38 AM syzbot > > > wrote: > > > > > > > > Hello, > > > > > > > > syzbot found the following crash on: > > > > > > > > HEAD commit: 459c5fb4 Merge branch 'mscc-PTP-support' > > > > git tree: net-next > > > > console output: https://syzkaller.appspot.com/x/log.txt?x=13f2d33c600000 > > > > kernel config: https://syzkaller.appspot.com/x/.config?x=d4cf1ffb87d590d7 > > > > dashboard link: https://syzkaller.appspot.com/bug?extid=eb349eeee854e389c36d > > > > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > > > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=111849e2600000 > > > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1442c25a600000 > > > > > > > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > > > > Reported-by: syzbot+eb349eeee854e389c36d@syzkaller.appspotmail.com > > > > > > > > ------------[ cut here ]------------ > > > > kernel BUG at include/linux/skbuff.h:2225! > > > > invalid opcode: 0000 [#1] PREEMPT SMP KASAN > > > > CPU: 0 PID: 9030 Comm: syz-executor649 Not tainted 5.3.0-rc3+ #134 > > > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > > > > Google 01/01/2011 > > > > RIP: 0010:__skb_pull include/linux/skbuff.h:2225 [inline] > > > > RIP: 0010:__skb_pull include/linux/skbuff.h:2222 [inline] > > > > RIP: 0010:skb_pull_inline include/linux/skbuff.h:2231 [inline] > > > > RIP: 0010:skb_pull+0xea/0x110 net/core/skbuff.c:1902 > > > > Code: 9d c8 00 00 00 49 89 dc 49 89 9d c8 00 00 00 e8 9c e5 dd fb 4c 89 e0 > > > > 5b 41 5c 41 5d 41 5e 5d c3 45 31 e4 eb ea e8 86 e5 dd fb <0f> 0b e8 df 13 > > > > 18 fc e9 44 ff ff ff e8 d5 13 18 fc eb 8a e8 ee 13 > > > > RSP: 0018:ffff88808ac96e10 EFLAGS: 00010293 > > > > RAX: ffff88809c546000 RBX: 0000000000000004 RCX: ffffffff8594a3a6 > > > > RDX: 0000000000000000 RSI: ffffffff8594a3fa RDI: 0000000000000004 > > > > RBP: ffff88808ac96e30 R08: ffff88809c546000 R09: fffffbfff14a8f4f > > > > R10: fffffbfff14a8f4e R11: ffffffff8a547a77 R12: 0000000095e28bcc > > > > R13: ffff88808ac97478 R14: 00000000ffff8880 R15: ffff88808ac97478 > > > > FS: 0000555556549880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 > > > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > > > CR2: 0000000020000100 CR3: 0000000089c3c000 CR4: 00000000001406f0 > > > > Call Trace: > > > > sctp_inq_pop+0x2f1/0xd80 net/sctp/inqueue.c:202 > > > > sctp_endpoint_bh_rcv+0x184/0x8d0 net/sctp/endpointola.c:385 > > > > sctp_inq_push+0x1e4/0x280 net/sctp/inqueue.c:80 > > > > sctp_rcv+0x2807/0x3590 net/sctp/input.c:256 > > > > sctp6_rcv+0x17/0x30 net/sctp/ipv6.c:1049 > > > > ip6_protocol_deliver_rcu+0x2fe/0x1660 net/ipv6/ip6_input.c:397 > > > > ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:438 > > > > NF_HOOK include/linux/netfilter.h:305 [inline] > > > > NF_HOOK include/linux/netfilter.h:299 [inline] > > > > ip6_input+0xe4/0x3f0 net/ipv6/ip6_input.c:447 > > > > dst_input include/net/dst.h:442 [inline] > > > > ip6_sublist_rcv_finish+0x98/0x1e0 net/ipv6/ip6_input.c:84 > > > Looks skb_list_del_init() should be called in ip6_sublist_rcv_finish, > > > as does in ip_sublist_rcv_finish(). > > > > This was recently introduced, right? Only in net-next and linux-next. > > Otherwise, is it a remote DoS? If so and if it's present in any > > releases, may need a CVE. > I need to reproduce and confirm it, will let you know. The panic could be triggered since the listified RX support for GRO_NORMAL skbs: https://patchwork.ozlabs.org/cover/1142808/ (it's only in net-next now, I will post a fix soon) But the bug itself is not really related with the patch series above. the issue here is pretty much like what this patch fixed: https://patchwork.ozlabs.org/patch/942541/ I didn't see a CVE for it, maybe because it was only on net-next too.