Subject: BUG: corrupted list in remove_wait_queue

From: syzbot <[email-masked]>
Date: Wed, 21 Mar 2018 09:10:00 -0700

Hello,

syzbot hit the following crash on upstream commit
3215b9d57a2c75c4305a3956ca303d7004485200 (Wed Mar 21 00:44:27 2018 +0000)
Merge tag 'clk-fixes-for-linus' of  
git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
syzbot dashboard link:  
https://syzkaller.appspot.com/bug?extid=c0272972b01b872e604a

Unfortunately, I don't have any reproducer for this crash yet.
Raw console output is attached.
compiler: gcc (GCC) 7.1.1 20170620
.config is attached.

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Reported-by: [email-masked]
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TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending  
cookies.  Check SNMP counters.
list_del corruption, 0000000031be84c4->next is LIST_POISON1  
(0000000036055018)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:47!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
    (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 1219 Comm: syz-executor1 Not tainted 4.16.0-rc6+ #361
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RIP: 0010:__list_del_entry_valid+0xd3/0x150 lib/list_debug.c:45
RSP: 0018:ffff8801ae8bf1b8 EFLAGS: 00010086
RAX: 000000000000004e RBX: dead000000000200 RCX: 0000000000000000
RDX: 000000000000004e RSI: 1ffff10035d17dec RDI: ffffed0035d17e2b
RBP: ffff8801ae8bf1d0 R08: 0000000000000000 R09: 1ffff10035d17d93
R10: ffff8801ae8bf090 R11: 0000000000000002 R12: dead000000000100
R13: ffff8801a084bc98 R14: ffff8801a084bca0 R15: ffff8801b1f168c0
FS:  00007f7733a6e700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000930008 CR3: 0000000006e22004 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  __list_del_entry include/linux/list.h:117 [inline]
  list_del include/linux/list.h:125 [inline]
  __remove_wait_queue include/linux/wait.h:184 [inline]
  remove_wait_queue+0x90/0x350 kernel/sched/wait.c:51
  vhost_poll_stop+0x46/0x90 drivers/vhost/vhost.c:229
  vhost_net_disable_vq drivers/vhost/net.c:405 [inline]
  vhost_net_stop_vq+0x90/0xf0 drivers/vhost/net.c:972
  vhost_net_stop drivers/vhost/net.c:982 [inline]
  vhost_net_release+0x49/0x190 drivers/vhost/net.c:1015
  __fput+0x327/0x7e0 fs/file_table.c:209
  ____fput+0x15/0x20 fs/file_table.c:243
  task_work_run+0x199/0x270 kernel/task_work.c:113
  exit_task_work include/linux/task_work.h:22 [inline]
  do_exit+0x9bb/0x1ad0 kernel/exit.c:865
  do_group_exit+0x149/0x400 kernel/exit.c:968
  get_signal+0x73a/0x16d0 kernel/signal.c:2469
  do_signal+0x90/0x1e90 arch/x86/kernel/signal.c:809
  exit_to_usermode_loop+0x258/0x2f0 arch/x86/entry/common.c:162
  prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
  syscall_return_slowpath arch/x86/entry/common.c:265 [inline]
  do_syscall_64+0x6ec/0x940 arch/x86/entry/common.c:292
  entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x453e69
RSP: 002b:00007f7733a6dce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000072c038 RCX: 0000000000453e69
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000072c038
RBP: 000000000072c038 R08: 0000000000000000 R09: 000000000072c010
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000a3e8ef R14: 00007f7733a6e9c0 R15: 0000000000000002
Code: 8f 00 00 00 49 8b 54 24 08 48 39 f2 75 3b 48 83 c4 08 b8 01 00 00 00  
5b 41 5c 5d c3 4c 89 e2 48 c7 c7 00 80 40 86 e8 45 e4 fb fe <0f> 0b 48 c7  
c7 60 80 40 86 e8 37 e4 fb fe 0f 0b 48 c7 c7 c0 80
RIP: __list_del_entry_valid+0xd3/0x150 lib/list_debug.c:45 RSP:  
ffff8801ae8bf1b8
---[ end trace 76e2c00ea8a52161 ]---

---
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