------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 16 at lib/refcount.c:28 refcount_warn_saturate+0xd8/0xe0 lib/refcount.c:28
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.9.0-rc1-syzkaller #0
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+0xb3/0xec lib/dump_stack.c:118
 panic+0x115/0x2fa kernel/panic.c:231
 __warn.cold.13+0x20/0x25 kernel/panic.c:600
 report_bug+0xc0/0xf0 lib/bug.c:198
 handle_bug+0x35/0x90 arch/x86/kernel/traps.c:234
 exc_invalid_op+0x13/0x60 arch/x86/kernel/traps.c:254
 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536
RIP: 0010:refcount_warn_saturate+0xd8/0xe0 lib/refcount.c:28
Code: ff 48 c7 c7 a0 90 f1 83 c6 05 5a 2b 91 02 01 e8 d9 84 4f ff 0f 0b c3 48 c7 c7 48 90 f1 83 c6 05 46 2b 91 02 01 e8 c3 84 4f ff <0f> 0b c3 0f 1f 44 00 00 8b 07 3d 00 00 00 c0 74 12 83 f8 01 74 46
RSP: 0018:ffffc90000cf3de0 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff888110fa8ca8 RCX: 0000000000000101
RDX: 0000000080000101 RSI: ffffffff8401fc29 RDI: 00000000ffffffff
RBP: ffff888110fa8800 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000001 R11: 8de418ac461b6a33 R12: ffffffff842f5ba0
R13: ffff888110fa8ca8 R14: 0000000000000000 R15: ffffffff81260806
 __sk_destruct+0x1c/0x250 net/core/sock.c:1778
 rcu_do_batch kernel/rcu/tree.c:2428 [inline]
 rcu_core+0x481/0x7f0 kernel/rcu/tree.c:2656
 __do_softirq+0xf6/0x508 kernel/softirq.c:298
 run_ksoftirqd+0x4b/0x80 kernel/softirq.c:652
 smpboot_thread_fn+0x1c5/0x280 kernel/smpboot.c:165
 kthread+0x148/0x170 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Kernel Offset: disabled
Rebooting in 86400 seconds..