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=-0.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 674E0ECE566 for ; Thu, 20 Sep 2018 20:06:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 17F6B214C2 for ; Thu, 20 Sep 2018 20:06:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 17F6B214C2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388370AbeIUBvL (ORCPT ); Thu, 20 Sep 2018 21:51:11 -0400 Received: from mail-io1-f71.google.com ([209.85.166.71]:45997 "EHLO mail-io1-f71.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387985AbeIUBvL (ORCPT ); Thu, 20 Sep 2018 21:51:11 -0400 Received: by mail-io1-f71.google.com with SMTP id o4-v6so14093979iob.12 for ; Thu, 20 Sep 2018 13:06:02 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:in-reply-to:message-id:subject :from:to; bh=0qggMsOmF4DbTmazThoyBnsCsKdoxXdPNe+Rp39G39c=; b=FItkfkRiH2DKXqgQiuafMteoiYme8d+l39WFjUer/M/iL3TAL+0RUSG7JhhkbGq+s8 sWyAtd5y1QO94nomrdq3F92NtrT7LwdfmxzxDceQpvif70QAfEVxz6XPxfT2r/uc5hFr QJl+HlBgBttcqv8LVx5tPVs7+AJJBsQ6HIHCFPPu469WxUCu7nSjuiD/y47zxZtV4opK XczhzKFF8qNpKntM+j8LF71z6qFxkkjCLjlg3OD0/3vSsLAPoJU9TN6gaVfBVxM/+6hx FUE26R+YKOvbTz5nyT8n5vXeBFmshUu2mvYhNuw2O49/uj9K/s5dPKd7ho5j1enmgrIq D0FA== X-Gm-Message-State: APzg51BgCxXPu4zcgXZvCz5dTKssVgMIKlrh9u9Wx2VYFNBLw3asp7bU cyqX1lYE+NVjQvbcFY7is7PdPwaUl1h4sRQF45YknyLcm6Vp X-Google-Smtp-Source: ANB0VdZKmyzYh4biq7t985dN2rpJDnR8eDKUurZpoIFAFMMnt11lo6wcYEH7kF5ChJ1DfKUyu26EklC7tGKWiQjPGb7GLQ+eaj16 MIME-Version: 1.0 X-Received: by 2002:a24:9f84:: with SMTP id c126-v6mr3251128ite.29.1537473961966; Thu, 20 Sep 2018 13:06:01 -0700 (PDT) Date: Thu, 20 Sep 2018 13:06:01 -0700 In-Reply-To: <0000000000002b42040573b8495a@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000005ac54e0576530d24@google.com> Subject: Re: WARNING: refcount bug in igmp_start_timer From: syzbot To: davem@davemloft.net, kuznet@ms2.inr.ac.ru, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, yoshfuji@linux-ipv6.org Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org syzbot has found a reproducer for the following crash on: HEAD commit: ae596de1a0c8 Compiler Attributes: naked can be shared git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=15bdb156400000 kernel config: https://syzkaller.appspot.com/x/.config?x=5fa12be50bca08d8 dashboard link: https://syzkaller.appspot.com/bug?extid=e28037ac1c96d2a86e89 compiler: gcc (GCC) 8.0.1 20180413 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=178537da400000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+e28037ac1c96d2a86e89@syzkaller.appspotmail.com IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready 8021q: adding VLAN 0 to HW filter on device team0 ------------[ cut here ]------------ refcount_t: increment on 0; use-after-free. WARNING: CPU: 1 PID: 13494 at lib/refcount.c:153 refcount_inc_checked+0x5d/0x70 lib/refcount.c:153 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 13494 Comm: syz-executor0 Not tainted 4.19.0-rc4+ #26 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+0x1c4/0x2b4 lib/dump_stack.c:113 panic+0x238/0x4e7 kernel/panic.c:184 __warn.cold.8+0x163/0x1ba kernel/panic.c:536 report_bug+0x254/0x2d0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:993 RIP: 0010:refcount_inc_checked+0x5d/0x70 lib/refcount.c:153 Code: 1d a2 83 91 06 31 ff 89 de e8 7f 8e ef fd 84 db 75 df e8 a6 8d ef fd 48 c7 c7 40 82 44 88 c6 05 82 83 91 06 01 e8 63 74 b9 fd <0f> 0b eb c3 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 RSP: 0018:ffff8801c7fdeca0 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8164fce5 RDI: 0000000000000005 RBP: ffff8801c7fdeca8 R08: ffff8801c67da1c0 R09: ffffed003b5e3ee2 R10: ffffed003b5e3ee2 R11: ffff8801daf1f717 R12: 0000000000000000 R13: 0000000000000008 R14: ffff8801b465f640 R15: dffffc0000000000 igmp_start_timer+0xaf/0xe0 net/ipv4/igmp.c:217 igmp_mod_timer net/ipv4/igmp.c:255 [inline] igmp_heard_query net/ipv4/igmp.c:1026 [inline] igmp_rcv+0x190e/0x3020 net/ipv4/igmp.c:1061 ip_local_deliver_finish+0x2e9/0xda0 net/ipv4/ip_input.c:215 NF_HOOK include/linux/netfilter.h:287 [inline] ip_local_deliver+0x1e9/0x750 net/ipv4/ip_input.c:256 dst_input include/net/dst.h:450 [inline] ip_rcv_finish+0x1f9/0x300 net/ipv4/ip_input.c:415 NF_HOOK include/linux/netfilter.h:287 [inline] ip_rcv+0xed/0x610 net/ipv4/ip_input.c:524 __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4891 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5001 netif_receive_skb_internal+0x12c/0x620 net/core/dev.c:5104 napi_frags_finish net/core/dev.c:5642 [inline] napi_gro_frags+0x75a/0xc90 net/core/dev.c:5715 tun_get_user+0x31d5/0x42a0 drivers/net/tun.c:1965 tun_chr_write_iter+0xb9/0x154 drivers/net/tun.c:2010 call_write_iter include/linux/fs.h:1808 [inline] do_iter_readv_writev+0x8b0/0xa80 fs/read_write.c:680 do_iter_write+0x185/0x5f0 fs/read_write.c:959 vfs_writev+0x1f1/0x360 fs/read_write.c:1004 do_writev+0x11a/0x310 fs/read_write.c:1039 __do_sys_writev fs/read_write.c:1112 [inline] __se_sys_writev fs/read_write.c:1109 [inline] __x64_sys_writev+0x75/0xb0 fs/read_write.c:1109 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457531 Code: 75 14 b8 14 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 54 b5 fb ff c3 48 83 ec 08 e8 1a 2d 00 00 48 89 04 24 b8 14 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 63 2d 00 00 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007f1448a89ba0 EFLAGS: 00000293 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 000000000000002a RCX: 0000000000457531 RDX: 0000000000000001 RSI: 00007f1448a89bf0 RDI: 00000000000000f0 RBP: 0000000020000240 R08: 00000000000000f0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00000000ffffffff R13: 00000000004d7938 R14: 00000000004c48b4 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds..