general protection fault, probably for non-canonical address 0xdffffc0000000008: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000040-0x0000000000000047] CPU: 0 PID: 25 Comm: kworker/u4:1 Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:dst_dev_put+0x1f/0x2a0 net/core/dst.c:156 Code: 1f 84 00 00 00 00 00 0f 1f 40 00 41 55 41 54 55 53 48 89 fb e8 02 92 66 fa 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 61 02 00 00 48 8d 7b 3a 4c 8b 23 48 b8 00 00 00 RSP: 0018:ffffc90000007d80 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000042 RCX: 0000000000000100 RDX: 0000000000000008 RSI: ffffffff870e30ae RDI: 0000000000000042 RBP: 0000000000000000 R08: 0000000000000000 R09: ffff88802158256b R10: ffffffff879eebd5 R11: 0000000000000000 R12: 0000000000000007 R13: fffffbfff1b92da4 R14: 0000607f4604ba50 R15: 0000000000000042 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe2f227f78 CR3: 000000000bc8e000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rt_fibinfo_free_cpus.part.0+0xda/0x140 net/ipv4/fib_semantics.c:202 rt_fibinfo_free_cpus net/ipv4/fib_semantics.c:194 [inline] fib_nh_common_release+0x10c/0x350 net/ipv4/fib_semantics.c:215 fib6_info_destroy_rcu+0x187/0x210 net/ipv6/ip6_fib.c:175 rcu_do_batch kernel/rcu/tree.c:2558 [inline] rcu_core+0x7ab/0x13b0 kernel/rcu/tree.c:2793 __do_softirq+0x29b/0x9f6 kernel/softirq.c:559 invoke_softirq kernel/softirq.c:433 [inline] __irq_exit_rcu+0x136/0x200 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632 RIP: 0010:lock_is_held_type+0xfd/0x140 kernel/locking/lockdep.c:5560 Code: 00 00 b8 ff ff ff ff 65 0f c1 05 4e 9c eb 76 83 f8 01 75 29 9c 58 f6 c4 02 75 3d 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 <44> 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 45 31 ed eb b9 0f 0b 48 RSP: 0018:ffffc90000dff730 EFLAGS: 00000296 RAX: 0000000000000046 RBX: 0000000000000004 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff8bf796a0 R08: 0000000000000001 R09: ffffffff9023f8c7 R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880124654c0 R13: 0000000000000000 R14: 00000000ffffffff R15: ffff888012465f30 lock_is_held include/linux/lockdep.h:283 [inline] ___might_sleep+0x23f/0x2c0 kernel/sched/core.c:8304 get_next_corpse net/netfilter/nf_conntrack_core.c:2238 [inline] nf_ct_iterate_cleanup+0x16d/0x450 net/netfilter/nf_conntrack_core.c:2260 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2348 [inline] nf_ct_iterate_cleanup_net+0x290/0x3f0 net/netfilter/nf_conntrack_core.c:2332 masq_device_event+0xae/0xe0 net/netfilter/nf_nat_masquerade.c:88 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2121 call_netdevice_notifiers_extack net/core/dev.c:2133 [inline] call_netdevice_notifiers net/core/dev.c:2147 [inline] dev_close_many+0x2ff/0x620 net/core/dev.c:1722 unregister_netdevice_many+0x3ff/0x1790 net/core/dev.c:10990 default_device_exit_batch+0x2fa/0x3c0 net/core/dev.c:11543 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:178 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:595 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Modules linked in: ---[ end trace 10f66c45d19f4783 ]--- RIP: 0010:dst_dev_put+0x1f/0x2a0 net/core/dst.c:156 Code: 1f 84 00 00 00 00 00 0f 1f 40 00 41 55 41 54 55 53 48 89 fb e8 02 92 66 fa 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 61 02 00 00 48 8d 7b 3a 4c 8b 23 48 b8 00 00 00 RSP: 0018:ffffc90000007d80 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000042 RCX: 0000000000000100 RDX: 0000000000000008 RSI: ffffffff870e30ae RDI: 0000000000000042 RBP: 0000000000000000 R08: 0000000000000000 R09: ffff88802158256b R10: ffffffff879eebd5 R11: 0000000000000000 R12: 0000000000000007 R13: fffffbfff1b92da4 R14: 0000607f4604ba50 R15: 0000000000000042 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe2f227f78 CR3: 000000000bc8e000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400