general protection fault, probably for non-canonical address 0xdffffc000000000e: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000070-0x0000000000000077] CPU: 0 PID: 20284 Comm: syz-executor.5 Not tainted 5.14.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 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 b0 9f 9c 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:ffffc90001a47228 EFLAGS: 00010202 RAX: 000000000000000e RBX: dffffc0000000000 RCX: ffffc9001497b000 RDX: 0000000000040000 RSI: ffffffff87d90a00 RDI: 0000000000000071 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8fced987 R10: ffffffff87d90994 R11: 0000000000000000 R12: 0000000000000002 R13: ffff888021181ea0 R14: ffffed10042303de R15: 0000000000000001 FS: 00007f2fd8c94700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000970004 CR3: 0000000027904000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 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:1983 [inline] fib6_del+0xa28/0x15d0 net/ipv6/ip6_fib.c:2028 fib6_clean_node+0x393/0x5c0 net/ipv6/ip6_fib.c:2190 fib6_walk_continue+0x400/0x720 net/ipv6/ip6_fib.c:2112 fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2160 fib6_clean_tree+0xdb/0x120 net/ipv6/ip6_fib.c:2240 __fib6_clean_all+0x107/0x2a0 net/ipv6/ip6_fib.c:2256 rt6_sync_down_dev net/ipv6/route.c:4877 [inline] rt6_disable_ip+0x844/0x940 net/ipv6/route.c:4882 addrconf_ifdown.isra.0+0xf6/0x15b0 net/ipv6/addrconf.c:3712 addrconf_notify+0x606/0x2400 net/ipv6/addrconf.c:3637 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1996 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline] call_netdevice_notifiers net/core/dev.c:2022 [inline] __dev_notify_flags+0x1da/0x2b0 net/core/dev.c:8797 dev_change_flags+0x112/0x170 net/core/dev.c:8833 dev_ifsioc+0xb22/0x10c0 net/core/dev_ioctl.c:324 dev_ioctl+0x1b9/0xee0 net/core/dev_ioctl.c:587 sock_do_ioctl+0x18b/0x210 net/socket.c:1129 sock_ioctl+0x2f1/0x640 net/socket.c:1232 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2fd8c94188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9 RDX: 0000000020000900 RSI: 0000000000008914 RDI: 0000000000000003 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007ffe2e5511df R14: 00007f2fd8c94300 R15: 0000000000022000 Modules linked in: ---[ end trace e27ae9f792e3ee54 ]--- 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 b0 9f 9c 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:ffffc90001a47228 EFLAGS: 00010202 RAX: 000000000000000e RBX: dffffc0000000000 RCX: ffffc9001497b000 RDX: 0000000000040000 RSI: ffffffff87d90a00 RDI: 0000000000000071 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8fced987 R10: ffffffff87d90994 R11: 0000000000000000 R12: 0000000000000002 R13: ffff888021181ea0 R14: ffffed10042303de R15: 0000000000000001 FS: 00007f2fd8c94700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000970004 CR3: 0000000027904000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 ---------------- 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 b0 9f 9c f9 callq 0xf99c9fcf 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)