------------[ cut here ]------------
refcount_t: increment on 0; use-after-free.
WARNING: CPU: 1 PID: 0 at lib/refcount.c:156 refcount_inc_checked+0x4b/0x50 lib/refcount.c:156
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.3.0-rc1+ #49
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+0x1d8/0x2f8 lib/dump_stack.c:113
 panic+0x29b/0x7d9 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:1026
RIP: 0010:refcount_inc_checked+0x4b/0x50 lib/refcount.c:156
Code: 3d 1f b3 93 05 01 75 08 e8 a2 f3 10 fe 5b 5d c3 e8 9a f3 10 fe c6 05 09 b3 93 05 01 48 c7 c7 09 1c 88 88 31 c0 e8 55 0b e2 fd <0f> 0b eb df 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0
RSP: 0018:ffff8880aeb09b40 EFLAGS: 00010246
RAX: a0f5e7b9d78a3100 RBX: ffff88808d788bc0 RCX: ffff8880a98bc340
RDX: 0000000000000302 RSI: 0000000000000302 RDI: 0000000000000000
RBP: ffff8880aeb09b48 R08: ffffffff81606214 R09: fffffbfff13bc4b3
R10: fffffbfff13bc4b3 R11: 0000000000000000 R12: ffff88809563e180
R13: dffffc0000000000 R14: 0000000000000004 R15: ffff88808d788b40
 sock_hold include/net/sock.h:649 [inline]
 sk_add_node include/net/sock.h:701 [inline]
 nr_insert_socket net/netrom/af_netrom.c:137 [inline]
 nr_rx_frame+0x17bc/0x1e40 net/netrom/af_netrom.c:1023
 nr_loopback_timer+0x6a/0x140 net/netrom/nr_loopback.c:59
 call_timer_fn+0xec/0x200 kernel/time/timer.c:1322
 expire_timers kernel/time/timer.c:1366 [inline]
 __run_timers+0x7cd/0x9c0 kernel/time/timer.c:1685
 run_timer_softirq+0x4a/0x90 kernel/time/timer.c:1698
 __do_softirq+0x333/0x7c4 arch/x86/include/asm/paravirt.h:778
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x227/0x230 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:537 [inline]
 smp_apic_timer_interrupt+0x113/0x280 arch/x86/kernel/apic/apic.c:1095
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:828
 </IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: 06 fa eb ae 89 d9 80 e1 07 80 c1 03 38 c1 7c ba 48 89 df e8 e4 35 06 fa eb b0 90 90 e9 07 00 00 00 0f 00 2d 46 38 56 00 fb f4 <c3> 90 e9 07 00 00 00 0f 00 2d 36 38 56 00 f4 c3 90 90 55 48 89 e5
RSP: 0018:ffff8880a98c7d38 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11950e3 RBX: ffff8880a98bc340 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff812d2b4a RDI: ffff8880a98bcb78
RBP: ffff8880a98c7d40 R08: ffff8880a98bcb90 R09: ffffed1015317869
R10: ffffed1015317869 R11: 0000000000000000 R12: 0000000000000001
R13: 1ffff11015317868 R14: dffffc0000000000 R15: dffffc0000000000
 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:571
 default_idle_call+0x59/0xa0 kernel/sched/idle.c:94
 cpuidle_idle_call kernel/sched/idle.c:154 [inline]
 do_idle+0x180/0x780 kernel/sched/idle.c:263
 cpu_startup_entry+0x25/0x30 kernel/sched/idle.c:354
 start_secondary+0x3f4/0x490 arch/x86/kernel/smpboot.c:264
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241
Kernel Offset: disabled
Rebooting in 86400 seconds..