general protection fault, probably for non-canonical address 0xdffffd4a1ffffd44: 0000 [#1] PREEMPT SMP KASAN KASAN: probably user-memory-access in range [0x00000a50ffffea20-0x00000a50ffffea27] CPU: 1 PID: 17797 Comm: kworker/u4:9 Not tainted 5.12.0-rc8-next-20210422-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:unregister_sysctl_table fs/proc/proc_sysctl.c:1668 [inline] RIP: 0010:unregister_sysctl_table+0x4d/0x190 fs/proc/proc_sysctl.c:1660 Code: 5f ff 66 66 48 31 c0 48 85 ed 0f 84 9b 00 00 00 e8 68 e3 85 ff 48 8d 7d 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 07 01 00 00 4c 8b 65 20 4d 85 e4 74 49 e8 3b e3 RSP: 0018:ffffc900022077a8 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: ffff888019e78b00 RCX: 0000000000000000 RDX: 0000014a1ffffd44 RSI: ffffffff81ef15e8 RDI: 00000a50ffffea20 RBP: 00000a50ffffea00 R08: 0000000000000000 R09: ffffffff902068c7 R10: ffffffff8743976e R11: 0000000000000000 R12: 0000000000000100 R13: ffff88806d657008 R14: ffff88806d657000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff7a6fb9000 CR3: 0000000012a73000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: neigh_sysctl_unregister+0x5b/0x80 net/core/neighbour.c:3718 addrconf_ifdown.isra.0+0xf8f/0x15b0 net/ipv6/addrconf.c:3849 addrconf_notify+0x606/0x2410 net/ipv6/addrconf.c:3631 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] unregister_netdevice_many+0x951/0x1790 net/core/dev.c:11002 ip_tunnel_delete_nets+0x39f/0x5b0 net/ipv4/ip_tunnel.c:1113 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:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Modules linked in: ---[ end trace f8bea9bb0e819f7b ]--- RIP: 0010:unregister_sysctl_table fs/proc/proc_sysctl.c:1668 [inline] RIP: 0010:unregister_sysctl_table+0x4d/0x190 fs/proc/proc_sysctl.c:1660 Code: 5f ff 66 66 48 31 c0 48 85 ed 0f 84 9b 00 00 00 e8 68 e3 85 ff 48 8d 7d 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 07 01 00 00 4c 8b 65 20 4d 85 e4 74 49 e8 3b e3 RSP: 0018:ffffc900022077a8 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: ffff888019e78b00 RCX: 0000000000000000 RDX: 0000014a1ffffd44 RSI: ffffffff81ef15e8 RDI: 00000a50ffffea20 RBP: 00000a50ffffea00 R08: 0000000000000000 R09: ffffffff902068c7 R10: ffffffff8743976e R11: 0000000000000000 R12: 0000000000000100 R13: ffff88806d657008 R14: ffff88806d657000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff7a6fc0000 CR3: 0000000012a73000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400