Subject: general protection fault in __list_del_entry_valid

From: syzbot <[email-masked]>
Date: Tue, 24 Oct 2017 07:59:03 -0700

Hello,

syzkaller hit the following crash on  
aa69ff9e9c32db8aa84835baffea1b70c39e5112
git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.
C reproducer is attached
syzkaller reproducer is attached. See https://goo.gl/kgGztJ
for information about syzkaller reproducers

SELinux: unrecognized netlink message: protocol=6 nlmsg_type=65535  
sclass=netlink_xfrm_socket pig=2922 comm=syzkaller860091
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
SELinux: unrecognized netlink message: protocol=6 nlmsg_type=65535  
sclass=netlink_xfrm_socket pig=2923 comm=syzkaller860091
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
SELinux: unrecognized netlink message: protocol=6 nlmsg_type=65535  
sclass=netlink_xfrm_socket pig=2924 comm=syzkaller860091
    (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 23 Comm: kworker/0:1 Not tainted 4.13.0-rc4+ #2
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Workqueue: events netlink_sock_destruct_work
task: ffff8801da882600 task.stack: ffff8801da878000
RIP: 0010:__list_del_entry_valid+0x7e/0x150 lib/list_debug.c:51
RSP: 0018:ffff8801da87f0b8 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8801d198f1a0 RDI: ffff8801d198f1a8
RBP: ffff8801da87f0d0 R08: ffffffff8630d808 R09: ffff8801da87ea18
R10: ffff8801da87ef98 R11: 1ffff1003b51071b R12: 0000000000000000
R13: ffff8801da87f198 R14: ffffffff855864b8 R15: ffff8801d198f1a8
FS:  0000000000000000(0000) GS:ffff8801dc000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe339a7b84 CR3: 00000001d0304000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  __list_del_entry include/linux/list.h:116 [inline]
  list_del include/linux/list.h:124 [inline]
  xfrm_policy_walk_done+0xfa/0x310 net/xfrm/xfrm_policy.c:1049
  xfrm_dump_policy_done+0x73/0xa0 net/xfrm/xfrm_user.c:1690
  netlink_sock_destruct+0xfa/0x3c0 net/netlink/af_netlink.c:362
  __sk_destruct+0xfd/0x910 net/core/sock.c:1570
  sk_destruct+0x47/0x80 net/core/sock.c:1605
  __sk_free+0x57/0x230 net/core/sock.c:1613
  sk_free+0x2a/0x40 net/core/sock.c:1624
  netlink_sock_destruct_work+0x19/0x20 net/netlink/af_netlink.c:384
  process_one_work+0xbf3/0x1bc0 kernel/workqueue.c:2097
  worker_thread+0x223/0x1860 kernel/workqueue.c:2231
  kthread+0x35e/0x430 kernel/kthread.c:231
  ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:425
Code: 00 00 00 00 ad de 49 39 c4 74 66 48 b8 00 02 00 00 00 00 ad de 48 89  
da 48 39 c3 74 65 48 c1 ea 03 48 b8 00 00 00 00 00 fc ff df <80> 3c 02 00  
75 7b 48 8b 13 48 39 f2 75 57 49 8d 7c 24 08 48 b8
RIP: __list_del_entry_valid+0x7e/0x150 lib/list_debug.c:51 RSP:  
ffff8801da87f0b8
---[ end trace d2378690210613a6 ]---
Kernel panic - not syncing: Fatal exception in interrupt
SELinux: unrecognized netlink message: protocol=6 nlmsg_type=65535  
sclass=netlink_xfrm_socket pig=2925 comm=syzkaller860091
SELinux: unrecognized netlink message: protocol=6 nlmsg_type=65535  
sclass=netlink_xfrm_socket pig=2926 comm=syzkaller860091
SELinux: unrecognized netlink message: protocol=6 nlmsg_type=65535  
sclass=netlink_xfrm_socket pig=2927 comm=syzkaller860091
SELinux: unrecognized netlink message: protocol=6 nlmsg_type=65535  
sclass=netlink_xfrm_socket pig=2928 comm=syzkaller860091
SELinux: unrecognized netlink message: protocol=6 nlmsg_type=65535  
sclass=netlink_xfrm_socket pig=2929 comm=syzkaller860091
SELinux: unrecognized netlink message: protocol=6 nlmsg_type=65535  
sclass=netlink_xfrm_socket pig=2930 comm=syzkaller860091
Dumping ftrace buffer:
    (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..

---
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