IPVS: ftp: loaded support on port[0] = 21
netlink: 17 bytes leftover after parsing attributes in process `syz-executor493'.
==================================================================
BUG: KASAN: null-ptr-deref in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
BUG: KASAN: null-ptr-deref in refcount_sub_and_test_checked+0x9d/0x310 lib/refcount.c:179
Read of size 4 at addr 000000000000002e by task swapper/1/0

CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.19.0-rc6+ #245
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+0x1c4/0x2b4 lib/dump_stack.c:113
 kasan_report_error mm/kasan/report.c:352 [inline]
 kasan_report.cold.9+0x6d/0x309 mm/kasan/report.c:412
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
 kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272
 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
 refcount_sub_and_test_checked+0x9d/0x310 lib/refcount.c:179
 refcount_dec_and_test_checked+0x1a/0x20 lib/refcount.c:212
 ip_fib_metrics_put include/net/ip.h:428 [inline]
 fib6_info_destroy_rcu+0x2ef/0x3e0 net/ipv6/ip6_fib.c:204
 __rcu_reclaim kernel/rcu/rcu.h:236 [inline]
 rcu_do_batch kernel/rcu/tree.c:2576 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2880 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2847 [inline]
 rcu_process_callbacks+0xf23/0x2670 kernel/rcu/tree.c:2864
 __do_softirq+0x30b/0xad8 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:372 [inline]
 irq_exit+0x17f/0x1c0 kernel/softirq.c:412
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x1cb/0x760 arch/x86/kernel/apic/apic.c:1056
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:864
 </IRQ>
RIP: 0010:native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:57
Code: e9 2c ff ff ff 48 89 c7 48 89 45 d8 e8 53 50 10 fa 48 8b 45 d8 e9 ca fe ff ff 48 89 df e8 42 50 10 fa eb 82 55 48 89 e5 fb f4 <5d> c3 0f 1f 84 00 00 00 00 00 55 48 89 e5 f4 5d c3 90 90 90 90 90
RSP: 0018:ffff8801d9aefc30 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: 1ffff1003b35df8a RCX: ffffffff8184c1ba
RDX: 1ffffffff1263e44 RSI: ffffffff8184c1d4 RDI: ffffffff8931f220
RBP: ffff8801d9aefc30 R08: ffff8801d9adc3c0 R09: ffffed003b5e4732
R10: ffffed003b5e4732 R11: ffff8801daf23993 R12: ffff8801d9aefcf0
R13: ffffffff89f402e0 R14: 0000000000000000 R15: 0000000000000001
 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
 default_idle+0xbf/0x490 arch/x86/kernel/process.c:498
 arch_cpu_idle+0x10/0x20 arch/x86/kernel/process.c:489
 default_idle_call+0x6d/0x90 kernel/sched/idle.c:93
 cpuidle_idle_call kernel/sched/idle.c:153 [inline]
 do_idle+0x3db/0x5b0 kernel/sched/idle.c:262
 cpu_startup_entry+0x10c/0x120 kernel/sched/idle.c:368
 start_secondary+0x447/0x5f0 arch/x86/kernel/smpboot.c:271
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243
==================================================================