general protection fault, probably for non-canonical address 0xdffffc0000000021: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f] CPU: 0 PID: 10033 Comm: kworker/u4:5 Not tainted 5.9.0-rc1-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+0x1d/0x220 net/core/dst.c:156 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc 41 54 55 53 48 89 fb e8 94 20 35 fb 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 8b 01 00 00 48 8d 7b 3a 4c 8b 23 48 b8 00 00 00 RSP: 0018:ffffc90000007da0 EFLAGS: 00010207 RAX: dffffc0000000000 RBX: 000000000000010e RCX: ffffffff86c7ec75 RDX: 0000000000000021 RSI: ffffffff863f1e7c RDI: 000000000000010e RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8c5f39ff R10: 0000000000000000 R11: 0000000000000160 R12: 0000000000000007 R13: fffffbfff1564794 R14: 0000607f5167c5a8 R15: 000000000000010e FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000557ac3096160 CR3: 000000009f38f000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: rt_fibinfo_free_cpus.part.0+0xd0/0x120 net/ipv4/fib_semantics.c:202 rt_fibinfo_free_cpus net/ipv4/fib_semantics.c:194 [inline] fib_nh_common_release+0xff/0x330 net/ipv4/fib_semantics.c:215 fib6_info_destroy_rcu+0x187/0x210 net/ipv6/ip6_fib.c:174 rcu_do_batch kernel/rcu/tree.c:2428 [inline] rcu_core+0x5c7/0x1190 kernel/rcu/tree.c:2656 __do_softirq+0x2de/0xa24 kernel/softirq.c:298 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0x9d/0xd0 arch/x86/kernel/irq_64.c:77 do_softirq kernel/softirq.c:343 [inline] do_softirq+0x17b/0x1e0 kernel/softirq.c:330 __local_bh_enable_ip+0x14d/0x190 kernel/softirq.c:195 local_bh_enable include/linux/bottom_half.h:32 [inline] get_next_corpse net/netfilter/nf_conntrack_core.c:2226 [inline] nf_ct_iterate_cleanup+0x9e/0x330 net/netfilter/nf_conntrack_core.c:2249 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2334 [inline] nf_ct_iterate_cleanup_net+0x113/0x170 net/netfilter/nf_conntrack_core.c:2319 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:2033 call_netdevice_notifiers_extack net/core/dev.c:2045 [inline] call_netdevice_notifiers net/core/dev.c:2059 [inline] dev_close_many+0x30b/0x650 net/core/dev.c:1634 rollback_registered_many+0x3a8/0x1210 net/core/dev.c:9261 unregister_netdevice_many.part.0+0x1a/0x2f0 net/core/dev.c:10429 unregister_netdevice_many net/core/dev.c:10428 [inline] default_device_exit_batch+0x30c/0x3d0 net/core/dev.c:10912 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:189 cleanup_net+0x4ea/0xa00 net/core/net_namespace.c:603 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Modules linked in: ---[ end trace 1de00757c76e04e6 ]--- RIP: 0010:dst_dev_put+0x1d/0x220 net/core/dst.c:156 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc 41 54 55 53 48 89 fb e8 94 20 35 fb 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 8b 01 00 00 48 8d 7b 3a 4c 8b 23 48 b8 00 00 00 RSP: 0018:ffffc90000007da0 EFLAGS: 00010207 RAX: dffffc0000000000 RBX: 000000000000010e RCX: ffffffff86c7ec75 RDX: 0000000000000021 RSI: ffffffff863f1e7c RDI: 000000000000010e RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8c5f39ff R10: 0000000000000000 R11: 0000000000000160 R12: 0000000000000007 R13: fffffbfff1564794 R14: 0000607f5167c5a8 R15: 000000000000010e FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000557ac3096160 CR3: 000000009f38f000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600