WARNING in smc_unhash_sk (3)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: a55aa89a Linux 5.3-rc6
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=112dd212600000
kernel config: https://syzkaller.appspot.com/x/.config?x=58485246ad14eafe
dashboard link: https://syzkaller.appspot.com/bug?extid=8488cc4cf1c9e09b8b86
compiler: clang version 9.0.0 (/home/glider/llvm/clang
80fee25776c2fb61e74c1ecb1a523375c2500b69)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15426ebc600000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=116aca7a600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+8488cc...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 0 PID: 9198 at ./include/net/sock.h:666 sk_del_node_init
include/net/sock.h:666 [inline]
WARNING: CPU: 0 PID: 9198 at ./include/net/sock.h:666
smc_unhash_sk+0x21b/0x240 net/smc/af_smc.c:96
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 9198 Comm: syz-executor057 Not tainted 5.3.0-rc6 #93
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+0x1d8/0x2f8 lib/dump_stack.c:113
panic+0x25c/0x799 kernel/panic.c:219
__warn+0x22f/0x230 kernel/panic.c:576
report_bug+0x190/0x290 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:179 [inline]
do_error_trap+0xd7/0x440 arch/x86/kernel/traps.c:272
do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:291
invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1028
RIP: 0010:sk_del_node_init include/net/sock.h:666 [inline]
RIP: 0010:smc_unhash_sk+0x21b/0x240 net/smc/af_smc.c:96
Code: 48 89 df e8 07 b1 39 00 48 83 c4 20 5b 41 5c 41 5d 41 5e 41 5f 5d c3
e8 03 d7 31 fa 48 c7 c7 f2 c3 3a 88 31 c0 e8 28 1d 1b fa <0f> 0b eb 85 44
89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 5b ff ff ff 4c
RSP: 0018:ffff888094177b68 EFLAGS: 00010246
RAX: 0000000000000024 RBX: 0000000000000001 RCX: b964ece25f6b7c00
RDX: 0000000000000000 RSI: 0000000000000201 RDI: 0000000000000000
RBP: ffff888094177bb0 R08: ffffffff815cf7d4 R09: ffffed1015d46088
R10: ffffed1015d46088 R11: 0000000000000000 R12: ffff888098ccb240
R13: dffffc0000000000 R14: ffff888098ccb2c0 R15: ffff888098ccb268
__smc_release+0x1f8/0x3a0 net/smc/af_smc.c:146
smc_release+0x15b/0x2c0 net/smc/af_smc.c:185
__sock_release net/socket.c:590 [inline]
sock_close+0xe1/0x260 net/socket.c:1268
__fput+0x2e4/0x740 fs/file_table.c:280
____fput+0x15/0x20 fs/file_table.c:313
task_work_run+0x17e/0x1b0 kernel/task_work.c:113
exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0x5e8/0x21a0 kernel/exit.c:879
do_group_exit+0x15c/0x2b0 kernel/exit.c:983
__do_sys_exit_group+0x17/0x20 kernel/exit.c:994
__se_sys_exit_group+0x14/0x20 kernel/exit.c:992
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:992
do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x43ff28
Code: 00 00 be 3c 00 00 00 eb 19 66 0f 1f 84 00 00 00 00 00 48 89 d7 89 f0
0f 05 48 3d 00 f0 ff ff 77 21 f4 48 89 d7 44 89 c0 0f 05 <48> 3d 00 f0 ff
ff 76 e0 f7 d8 64 41 89 01 eb d8 0f 1f 84 00 00 00
RSP: 002b:00007ffefacce238 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff28
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004bf750 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 00000000200000c0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..


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