BUG: corrupted list in entry_SYSCALL_64_after_hwframe

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 4cc1feeb6ffc Merge git://git.kernel.org/pub/scm/linux/kern..
git tree: net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=14021925400000
kernel config: https://syzkaller.appspot.com/x/.config?x=d9655b05acfc97ff
dashboard link: https://syzkaller.appspot.com/bug?extid=02c22801a642e5c0d97e
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
CC: [da...@davemloft.net linux-...@vger.kernel.org
net...@vger.kernel.org]

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+02c228...@syzkaller.appspotmail.com

sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg+0xd5/0x120 net/socket.c:631
___sys_sendmsg+0x7fd/0x930 net/socket.c:2116
list_del corruption. next->prev should be ffff8881bb506ff0, but was
ffff8881d4406270
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:56!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 17 Comm: kworker/1:0 Not tainted 4.20.0-rc6+ #336
__sys_sendmsg+0x11d/0x280 net/socket.c:2154
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: events_power_efficient neigh_periodic_work
RIP: 0010:__list_del_entry_valid.cold.1+0x37/0x4a lib/list_debug.c:54
Code: e8 06 6f d2 fd 0f 0b 4c 89 ea 48 89 de 48 c7 c7 20 d9 60 88 e8 f2 6e
d2 fd 0f 0b 48 89 de 48 c7 c7 80 da 60 88 e8 e1 6e d2 fd <0f> 0b 48 89 de
48 c7 c7 20 da 60 88 e8 d0 6e d2 fd 0f 0b 48 89 d9
RSP: 0018:ffff8881d9b5f440 EFLAGS: 00010282
RAX: 0000000000000054 RBX: ffff8881bb506ff0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8165e485 RDI: 0000000000000005
__do_sys_sendmsg net/socket.c:2163 [inline]
__se_sys_sendmsg net/socket.c:2161 [inline]
__x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161
RBP: ffff8881d9b5f458 R08: ffff8881d9b4c480 R09: 0000000000000002
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
R10: 0000000000000000 R11: ffff8881d9b4c480 R12: ffff8881c647bdb0
R13: ffffffff89fd1320 R14: ffff8881d9b5f560 R15: 1ffff1103b36be94
FS: 0000000000000000(0000) GS:ffff8881daf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3d86533000 CR3: 00000001ceb1b000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
entry_SYSCALL_64_after_hwframe+0x49/0xbe
__list_del_entry include/linux/list.h:117 [inline]
list_del_init include/linux/list.h:159 [inline]
neigh_mark_dead+0x13b/0x410 net/core/neighbour.c:125
RIP: 0033:0x457659
Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fb5e62f0c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fb5e62f0c90 RCX: 0000000000457659
RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000004
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
neigh_periodic_work+0x89a/0xc30 net/core/neighbour.c:905
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb5e62f16d4
R13: 00000000004c4451 R14: 00000000004d7418 R15: 0000000000000005
process_one_work+0xc90/0x1c40 kernel/workqueue.c:2153
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 0 PID: 18341 Comm: syz-executor2 Not tainted 4.20.0-rc6+ #336
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+0x244/0x39d lib/dump_stack.c:113
fail_dump lib/fault-inject.c:51 [inline]
should_fail.cold.4+0xa/0x17 lib/fault-inject.c:149
worker_thread+0x17f/0x1390 kernel/workqueue.c:2296
__should_failslab+0x124/0x180 mm/failslab.c:32
should_failslab+0x9/0x14 mm/slab_common.c:1578
slab_pre_alloc_hook mm/slab.h:423 [inline]
slab_alloc_node mm/slab.c:3299 [inline]
kmem_cache_alloc_node+0x26e/0x730 mm/slab.c:3642
__alloc_skb+0x119/0x770 net/core/skbuff.c:193
kthread+0x35a/0x440 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Modules linked in:
---[ end trace 818733ef001358f1 ]---
alloc_skb include/linux/skbuff.h:1008 [inline]
netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline]
netlink_sendmsg+0xb29/0xfc0 net/netlink/af_netlink.c:1892
RIP: 0010:__list_del_entry_valid.cold.1+0x37/0x4a lib/list_debug.c:54
Code: e8 06 6f d2 fd 0f 0b 4c 89 ea 48 89 de 48 c7 c7 20 d9 60 88 e8 f2 6e
d2 fd 0f 0b 48 89 de 48 c7 c7 80 da 60 88 e8 e1 6e d2 fd <0f> 0b 48 89 de
48 c7 c7 20 da 60 88 e8 d0 6e d2 fd 0f 0b 48 89 d9
RSP: 0018:ffff8881d9b5f440 EFLAGS: 00010282
RAX: 0000000000000054 RBX: ffff8881bb506ff0 RCX: 0000000000000000
sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg+0xd5/0x120 net/socket.c:631
RDX: 0000000000000000 RSI: ffffffff8165e485 RDI: 0000000000000005
___sys_sendmsg+0x7fd/0x930 net/socket.c:2116
RBP: ffff8881d9b5f458 R08: ffff8881d9b4c480 R09: 0000000000000002
R10: 0000000000000000 R11: ffff8881d9b4c480 R12: ffff8881c647bdb0
R13: ffffffff89fd1320 R14: ffff8881d9b5f560 R15: 1ffff1103b36be94
FS: 0000000000000000(0000) GS:ffff8881daf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3d86533000 CR3: 00000001ceb1b000 CR4: 00000000001406e0
__sys_sendmsg+0x11d/0x280 net/socket.c:2154
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
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[syzbot]

> Since these lines are same, let's mark as dup.

> __list_del_entry include/linux/list.h:117 [inline]
> list_del_init include/linux/list.h:159 [inline]
> neigh_mark_dead+0x13b/0x410 net/core/neighbour.c:125

> #syz dup: KASAN: slab-out-of-bounds Read in neigh_mark_dead

Your 'dup:' command is accepted, but please keep
syzkaller-upst...@googlegroups.com mailing list in CC next
time. It serves as a history of what happened with each bug report. Thank
you.