general protection fault, probably for non-canonical address 0xdffffc000000000f: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000078-0x000000000000007f] CPU: 1 PID: 448 Comm: kworker/u4:14 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:__fib6_drop_pcpu_from.part.0+0x10b/0x390 net/ipv6/ip6_fib.c:978 Code: 48 c1 ea 03 80 3c 1a 00 0f 85 19 02 00 00 4c 8b 38 4d 85 ff 0f 84 7a ff ff ff e8 80 fe 8b f9 49 8d 7f 70 48 89 f8 48 c1 e8 03 <80> 3c 18 00 0f 85 4b 02 00 00 49 8b 47 70 48 3b 04 24 0f 85 52 ff RSP: 0018:ffffc90003ebf168 EFLAGS: 00010206 RAX: 000000000000000f RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffff88804bc01d00 RSI: ffffffff87ebac70 RDI: 0000000000000079 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8ff88abf R10: ffffffff87ebac04 R11: 0000000000000000 R12: 0000000000000002 R13: ffff888053c220a0 R14: ffffed100a78441e R15: 0000000000000009 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555557529708 CR3: 0000000052ed9000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __fib6_drop_pcpu_from net/ipv6/ip6_fib.c:960 [inline] fib6_drop_pcpu_from net/ipv6/ip6_fib.c:1021 [inline] fib6_purge_rt+0x6b9/0x820 net/ipv6/ip6_fib.c:1032 fib6_del_route net/ipv6/ip6_fib.c:1982 [inline] fib6_del+0xa28/0x15d0 net/ipv6/ip6_fib.c:2027 fib6_clean_node+0x393/0x5c0 net/ipv6/ip6_fib.c:2189 fib6_walk_continue+0x400/0x720 net/ipv6/ip6_fib.c:2111 fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2159 fib6_clean_tree+0xdb/0x120 net/ipv6/ip6_fib.c:2239 __fib6_clean_all+0x107/0x2a0 net/ipv6/ip6_fib.c:2255 rt6_sync_down_dev net/ipv6/route.c:4893 [inline] rt6_disable_ip+0x829/0x940 net/ipv6/route.c:4898 addrconf_ifdown.isra.0+0xf6/0x1630 net/ipv6/addrconf.c:3726 addrconf_notify+0xeb/0x1ba0 net/ipv6/addrconf.c:3651 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1919 call_netdevice_notifiers_extack net/core/dev.c:1931 [inline] call_netdevice_notifiers net/core/dev.c:1945 [inline] dev_close_many+0x2ff/0x620 net/core/dev.c:1520 unregister_netdevice_many+0x3ff/0x1850 net/core/dev.c:10380 ip6gre_exit_batch_net+0x4a7/0x760 net/ipv6/ip6_gre.c:1629 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:595 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Modules linked in: ---[ end trace c29be4439c370aae ]--- RIP: 0010:__fib6_drop_pcpu_from.part.0+0x10b/0x390 net/ipv6/ip6_fib.c:978 Code: 48 c1 ea 03 80 3c 1a 00 0f 85 19 02 00 00 4c 8b 38 4d 85 ff 0f 84 7a ff ff ff e8 80 fe 8b f9 49 8d 7f 70 48 89 f8 48 c1 e8 03 <80> 3c 18 00 0f 85 4b 02 00 00 49 8b 47 70 48 3b 04 24 0f 85 52 ff RSP: 0018:ffffc90003ebf168 EFLAGS: 00010206 RAX: 000000000000000f RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffff88804bc01d00 RSI: ffffffff87ebac70 RDI: 0000000000000079 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8ff88abf R10: ffffffff87ebac04 R11: 0000000000000000 R12: 0000000000000002 R13: ffff888053c220a0 R14: ffffed100a78441e R15: 0000000000000009 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555557529708 CR3: 0000000052ed9000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 48 c1 ea 03 shr $0x3,%rdx 4: 80 3c 1a 00 cmpb $0x0,(%rdx,%rbx,1) 8: 0f 85 19 02 00 00 jne 0x227 e: 4c 8b 38 mov (%rax),%r15 11: 4d 85 ff test %r15,%r15 14: 0f 84 7a ff ff ff je 0xffffff94 1a: e8 80 fe 8b f9 callq 0xf98bfe9f 1f: 49 8d 7f 70 lea 0x70(%r15),%rdi 23: 48 89 f8 mov %rdi,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1) <-- trapping instruction 2e: 0f 85 4b 02 00 00 jne 0x27f 34: 49 8b 47 70 mov 0x70(%r15),%rax 38: 48 3b 04 24 cmp (%rsp),%rax 3c: 0f .byte 0xf 3d: 85 52 ff test %edx,-0x1(%rdx)