Oops: general protection fault, probably for non-canonical address 0xdffffc0000000018: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x00000000000000c0-0x00000000000000c7] CPU: 0 UID: 0 PID: 47 Comm: kworker/u4:3 Not tainted 6.14.0-syzkaller-13443-g56f944529ec2 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:__in6_dev_get include/net/addrconf.h:347 [inline] RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:443 [inline] RIP: 0010:find_match+0xae/0xc10 net/ipv6/route.c:781 Code: 08 48 89 df e8 a3 75 63 f7 4c 89 64 24 40 48 89 d8 bb c0 00 00 00 48 03 18 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 74 75 63 f7 4c 8b 23 e8 ac 7d 66 01 RSP: 0018:ffffc9000062e4c0 EFLAGS: 00010206 RAX: 0000000000000018 RBX: 00000000000000c0 RCX: dffffc0000000000 RDX: ffff88801d53a440 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888035cf6720 R08: ffffffff8aca0adf R09: ffffc9000062e890 R10: ffffc9000062e6c0 R11: ffffffff8aca0920 R12: ffffc9000062e890 R13: ffff888035cf6737 R14: 1ffff11006b9ece6 R15: 1ffff11006b9ece4 FS: 0000000000000000(0000) GS:ffff88808c596000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f226e1a8074 CR3: 000000004099a000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rt6_nh_find_match+0xde/0x150 net/ipv6/route.c:821 nexthop_for_each_fib6_nh+0x1d0/0x410 net/ipv4/nexthop.c:1515 __find_rr_leaf+0x596/0x8f0 net/ipv6/route.c:862 find_rr_leaf net/ipv6/route.c:890 [inline] rt6_select net/ipv6/route.c:934 [inline] fib6_table_lookup+0x410/0xbf0 net/ipv6/route.c:2229 ip6_pol_route+0x26d/0x15f0 net/ipv6/route.c:2265 pol_lookup_func include/net/ip6_fib.h:616 [inline] fib6_rule_lookup+0x3c4/0x7a0 net/ipv6/fib6_rules.c:125 ip6_route_output_flags_noref net/ipv6/route.c:2673 [inline] ip6_route_output_flags+0x38e/0x610 net/ipv6/route.c:2685 ip6_route_output include/net/ip6_route.h:93 [inline] ip6_dst_lookup_tail+0x1b5/0x1510 net/ipv6/ip6_output.c:1128 ip6_dst_lookup_flow+0xbb/0x180 net/ipv6/ip6_output.c:1259 udp_tunnel6_dst_lookup+0x2cc/0x4f0 net/ipv6/ip6_udp_tunnel.c:165 geneve6_xmit_skb drivers/net/geneve.c:957 [inline] geneve_xmit+0xe7a/0x2e30 drivers/net/geneve.c:1043 __netdev_start_xmit include/linux/netdevice.h:5201 [inline] netdev_start_xmit include/linux/netdevice.h:5210 [inline] xmit_one net/core/dev.c:3783 [inline] dev_hard_start_xmit+0x2d4/0x840 net/core/dev.c:3799 __dev_queue_xmit+0x1b80/0x3f60 net/core/dev.c:4636 neigh_output include/net/neighbour.h:539 [inline] ip6_finish_output2+0x1296/0x1750 net/ipv6/ip6_output.c:141 __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline] ip6_finish_output+0x421/0x840 net/ipv6/ip6_output.c:226 NF_HOOK include/linux/netfilter.h:314 [inline] ndisc_send_skb+0xb58/0x1560 net/ipv6/ndisc.c:513 ndisc_send_ns+0xce/0x160 net/ipv6/ndisc.c:671 addrconf_dad_work+0xb2f/0x16a0 net/ipv6/addrconf.c:4282 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__in6_dev_get include/net/addrconf.h:347 [inline] RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:443 [inline] RIP: 0010:find_match+0xae/0xc10 net/ipv6/route.c:781 Code: 08 48 89 df e8 a3 75 63 f7 4c 89 64 24 40 48 89 d8 bb c0 00 00 00 48 03 18 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 74 75 63 f7 4c 8b 23 e8 ac 7d 66 01 RSP: 0018:ffffc9000062e4c0 EFLAGS: 00010206 RAX: 0000000000000018 RBX: 00000000000000c0 RCX: dffffc0000000000 RDX: ffff88801d53a440 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888035cf6720 R08: ffffffff8aca0adf R09: ffffc9000062e890 R10: ffffc9000062e6c0 R11: ffffffff8aca0920 R12: ffffc9000062e890 R13: ffff888035cf6737 R14: 1ffff11006b9ece6 R15: 1ffff11006b9ece4 FS: 0000000000000000(0000) GS:ffff88808c596000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f226e1a8074 CR3: 000000004099a000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 08 48 89 or %cl,-0x77(%rax) 3: df e8 fucomip %st(0),%st 5: a3 75 63 f7 4c 89 64 movabs %eax,0x402464894cf76375 c: 24 40 e: 48 89 d8 mov %rbx,%rax 11: bb c0 00 00 00 mov $0xc0,%ebx 16: 48 03 18 add (%rax),%rbx 19: 48 89 d8 mov %rbx,%rax 1c: 48 c1 e8 03 shr $0x3,%rax 20: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 27: fc ff df * 2a: 80 3c 08 00 cmpb $0x0,(%rax,%rcx,1) <-- trapping instruction 2e: 74 08 je 0x38 30: 48 89 df mov %rbx,%rdi 33: e8 74 75 63 f7 call 0xf76375ac 38: 4c 8b 23 mov (%rbx),%r12 3b: e8 ac 7d 66 01 call 0x1667dec