general protection fault in __list_del_entry_valid (3)

[syzbot]

Hello,

syzbot hit the following crash on net-next commit
c0b6edef0bf0e33c12eaf80c676ff09def011518 (Thu Mar 29 19:58:10 2018 +0000)
tc-testing: Add newline when writing test case files
syzbot dashboard link:  
https://syzkaller.appspot.com/bug?extid=0bb443b74ce09197e970

So far this crash happened 40 times on bpf-next, net-next, upstream.
C reproducer: https://syzkaller.appspot.com/x/repro.c?id=5934690573746176
syzkaller reproducer:  
https://syzkaller.appspot.com/x/repro.syz?id=5611083175821312
Raw console output:  
https://syzkaller.appspot.com/x/log.txt?id=6249721593069568
Kernel config:  
https://syzkaller.appspot.com/x/.config?id=3327544840960562528
compiler: gcc (GCC) 7.1.1 20170620

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Reported-by: syzbot+0bb443b74ce09197e970@xxxxxxxxxxxxxxxxxxxxxxxxx
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R13: ffffffffffffffff R14: 0000000000000000 R15: 0000000000000000
Name sequence creation failed, no memory
Failed to create subscription for {1020,0,4294967295}
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 4361 Comm: syzkaller865516 Not tainted 4.16.0-rc6+ #288
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RIP: 0010:__list_del_entry_valid+0x7e/0x150 lib/list_debug.c:51
RSP: 0018:ffff8801ae29eec8 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 00000000000001f8 RCX: 0000000000000000
RDX: 000000000000003f RSI: ffff8801c9eb6cd8 RDI: ffff8801c9eb6ce0
RBP: ffff8801ae29eee0 R08: ffffffff86b2cc9f R09: 0000000000000000
R10: ffff8801ae29eda8 R11: ffff8801d08cf710 R12: 0000000000400040
R13: ffff8801ae29f080 R14: ffff8801c9eb6cd8 R15: ffff8801d08cf6c0
FS:  0000000000000000(0000) GS:ffff8801db000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020265000 CR3: 000000000846a004 CR4: 00000000001606f0
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_init include/linux/list.h:159 [inline]
 tipc_nametbl_unsubscribe+0x337/0x990 net/tipc/name_table.c:808
 tipc_sub_unsubscribe+0x6d/0x2e0 net/tipc/subscr.c:164
 tipc_conn_delete_sub+0x324/0x4a0 net/tipc/topsrv.c:245
 tipc_topsrv_kern_unsubscr+0x21d/0x350 net/tipc/topsrv.c:598
 tipc_group_delete+0x2c0/0x3d0 net/tipc/group.c:231
 tipc_sk_leave+0x10b/0x200 net/tipc/socket.c:2800
 tipc_release+0x154/0xff0 net/tipc/socket.c:576
 sock_release+0x8d/0x1e0 net/socket.c:594
 sock_close+0x16/0x20 net/socket.c:1149
 __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
 SYSC_exit_group kernel/exit.c:979 [inline]
 SyS_exit_group+0x1d/0x20 kernel/exit.c:977
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x43f0d8
RSP: 002b:00007ffca6e03198 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043f0d8
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004bf1c8 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 0000000020265000 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000
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:  
ffff8801ae29eec8
---[ end trace 31f0221025ea0e3e ]---


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