------------[ cut here ]------------
refcount_t: increment on 0; use-after-free.
WARNING: CPU: 1 PID: 9733 at lib/refcount.c:156 refcount_inc_checked /lib/refcount.c:156 [inline]
WARNING: CPU: 1 PID: 9733 at lib/refcount.c:156 refcount_inc_checked+0x61/0x70 /lib/refcount.c:154
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 9733 Comm: udevd Not tainted 5.2.0+ #64
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack /lib/dump_stack.c:77 [inline]
 dump_stack+0x16f/0x1f0 /lib/dump_stack.c:113
 panic+0x2dc/0x755 /kernel/panic.c:219
 __warn.cold+0x20/0x4c /kernel/panic.c:576
 report_bug+0x263/0x2b0 /lib/bug.c:186
 fixup_bug /arch/x86/kernel/traps.c:179 [inline]
 fixup_bug /arch/x86/kernel/traps.c:174 [inline]
 do_error_trap+0x11b/0x200 /arch/x86/kernel/traps.c:272
 do_invalid_op+0x37/0x50 /arch/x86/kernel/traps.c:291
 invalid_op+0x23/0x30 /arch/x86/entry/entry_64.S:1026
RIP: 0010:refcount_inc_checked /lib/refcount.c:156 [inline]
RIP: 0010:refcount_inc_checked+0x61/0x70 /lib/refcount.c:154
Code: 1d 2c 9e 67 06 31 ff 89 de e8 9b 24 38 fe 84 db 75 dd e8 52 23 38 fe 48 c7 c7 40 d6 c5 87 c6 05 0c 9e 67 06 01 e8 87 4a 0a fe <0f> 0b eb c1 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57 41
RSP: 0000:ffff8880ae909bf0 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000100 RSI: ffffffff815b9de2 RDI: ffffed1015d21370
RBP: ffff8880ae909c00 R08: ffff888095bfe0c0 R09: fffffbfff14a6d5f
R10: fffffbfff14a6d5e R11: ffffffff8a536af7 R12: ffff88805a31b7c0
R13: ffff88805a31b7a8 R14: ffff888058292288 R15: ffff888058292260
 sock_hold /./include/net/sock.h:649 [inline]
 sk_add_node /./include/net/sock.h:701 [inline]
 nr_insert_socket+0x2d/0xe0 /net/netrom/af_netrom.c:137
 nr_rx_frame+0x1605/0x1e73 /net/netrom/af_netrom.c:1023
 nr_loopback_timer+0x7b/0x170 /net/netrom/nr_loopback.c:59
 call_timer_fn+0x1ac/0x700 /kernel/time/timer.c:1322
 expire_timers /kernel/time/timer.c:1366 [inline]
 __run_timers /kernel/time/timer.c:1685 [inline]
 __run_timers /kernel/time/timer.c:1653 [inline]
 run_timer_softirq+0x66c/0x16a0 /kernel/time/timer.c:1698
 __do_softirq+0x30d/0x970 /kernel/softirq.c:292
 invoke_softirq /kernel/softirq.c:373 [inline]
 irq_exit+0x1d0/0x200 /kernel/softirq.c:413
 exiting_irq /./arch/x86/include/asm/apic.h:537 [inline]
 smp_apic_timer_interrupt+0x14e/0x550 /arch/x86/kernel/apic/apic.c:1095
 apic_timer_interrupt+0xf/0x20 /arch/x86/entry/entry_64.S:828
 </IRQ>
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x13/0x20 /kernel/kcov.c:196
Code: 00 48 89 e5 48 8b 4d 08 e8 ba fe ff ff 5d c3 0f 1f 84 00 00 00 00 00 55 48 89 f2 48 89 fe bf 07 00 00 00 48 89 e5 48 8b 4d 08 <e8> 98 fe ff ff 5d c3 66 0f 1f 44 00 00 55 48 89 fa 48 89 e5 41 55
RSP: 0000:ffff888082207ca8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 000000009cdca067 RBX: 0000000000000000 RCX: ffffffff819b7473
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007
RBP: ffff888082207ca8 R08: ffff888095bfe0c0 R09: fffffbfff13491e8
R10: fffffbfff13491e7 R11: ffffffff89a48f3b R12: ffff88808f40c018
R13: ffff888082207e18 R14: ffff888099187040 R15: 0000000000000000
 pmd_devmap_trans_unstable+0x83/0x1d0 /mm/memory.c:3112
 handle_pte_fault /mm/memory.c:3810 [inline]
 __handle_mm_fault+0xb0c/0x3ce0 /mm/memory.c:3964
 handle_mm_fault+0x3bb/0xa90 /mm/memory.c:4001
 do_user_addr_fault /arch/x86/mm/fault.c:1444 [inline]
 __do_page_fault+0x536/0xdd0 /arch/x86/mm/fault.c:1509
 do_page_fault+0x38/0x536 /arch/x86/mm/fault.c:1533
 page_fault+0x39/0x40 /arch/x86/entry/entry_64.S:1200
RIP: 0033:0x7fb64ffc701c
Code: 83 ed 02 89 ea 49 8b 44 d4 08 48 39 c3 0f 84 64 06 00 00 48 85 c0 74 12 48 8b 48 08 c1 e9 04 83 e9 02 39 cd 0f 85 59 06 00 00 <48> 89 43 10 49 89 5c d4 08 48 83 c4 38 5b 5d 41 5c 41 5d 41 5e 41
RSP: 002b:00007fff91d0a570 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000723ea0 RCX: 00007fb64ffa7527
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00007fb6502d8e40
RBP: 0000000000000001 R08: 00007fb6502d8e40 R09: 00007fb6502d8e90
R10: 00007fb6502d8e90 R11: 0000000000000246 R12: 00007fb6502d8e40
R13: 0000000000625500 R14: 0000000000712030 R15: 000000000000000b
Kernel Offset: disabled
Rebooting in 86400 seconds..