Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 UID: 0 PID: 5982 Comm: syz.1.20 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:dst_dev include/net/dst.h:571 [inline] RIP: 0010:skb_dst_dev include/net/dst.h:586 [inline] RIP: 0010:skb_dst_dev_net include/net/dst.h:596 [inline] RIP: 0010:ipv6_frag_rcv+0x19c/0x2a20 net/ipv6/reassembly.c:328 Code: 5c 24 08 4c 89 74 24 10 48 8b 44 24 60 42 80 3c 28 00 74 08 48 89 df e8 42 15 21 f8 48 8b 03 49 89 c6 49 83 e6 fe 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 f7 e8 25 15 21 f8 bb 08 01 00 00 49 03 RSP: 0018:ffffc90003776d20 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88816d87a1d8 RCX: ffff88816bf65700 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003776f08 R08: ffffea0006d29400 R09: 0000000b00007ff5 R10: ffffea0006d29400 R11: ffffffff8a04b090 R12: 0000000000000040 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff888173607480 FS: 00007fa70abdd6c0(0000) GS:ffff8882a9f2e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000010000 CR3: 0000000112fa8000 CR4: 00000000000006f0 Call Trace: nf_flow_ip6_tunnel_proto net/netfilter/nf_flow_table_ip.c:383 [inline] nf_flow_skb_encap_protocol+0x9c2/0x1540 net/netfilter/nf_flow_table_ip.c:438 nf_flow_offload_ipv6_lookup net/netfilter/nf_flow_table_ip.c:1074 [inline] nf_flow_offload_ipv6_hook+0x13c/0x32a0 net/netfilter/nf_flow_table_ip.c:1102 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623 nf_hook_ingress include/linux/netfilter_netdev.h:34 [inline] nf_ingress net/core/dev.c:5900 [inline] __netif_receive_skb_core+0x241c/0x2f90 net/core/dev.c:5996 __netif_receive_skb_one_core net/core/dev.c:6135 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6250 netif_receive_skb_internal net/core/dev.c:6336 [inline] netif_receive_skb+0x1cb/0x790 net/core/dev.c:6395 tun_rx_batched+0x1b9/0x730 drivers/net/tun.c:1485 tun_get_user+0x2b65/0x3e90 drivers/net/tun.c:1953 tun_chr_write_iter+0x113/0x200 drivers/net/tun.c:1999 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x5c9/0xb30 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa70b58f7c9 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa70abdd038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fa70b7e6090 RCX: 00007fa70b58f7c9 RDX: 000000000000fdef RSI: 0000200000000340 RDI: 0000000000000003 RBP: 00007fa70b5f297f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa70b7e6128 R14: 00007fa70b7e6090 R15: 00007ffcd9538b88 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:dst_dev include/net/dst.h:571 [inline] RIP: 0010:skb_dst_dev include/net/dst.h:586 [inline] RIP: 0010:skb_dst_dev_net include/net/dst.h:596 [inline] RIP: 0010:ipv6_frag_rcv+0x19c/0x2a20 net/ipv6/reassembly.c:328 Code: 5c 24 08 4c 89 74 24 10 48 8b 44 24 60 42 80 3c 28 00 74 08 48 89 df e8 42 15 21 f8 48 8b 03 49 89 c6 49 83 e6 fe 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 f7 e8 25 15 21 f8 bb 08 01 00 00 49 03 RSP: 0018:ffffc90003776d20 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88816d87a1d8 RCX: ffff88816bf65700 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003776f08 R08: ffffea0006d29400 R09: 0000000b00007ff5 R10: ffffea0006d29400 R11: ffffffff8a04b090 R12: 0000000000000040 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff888173607480 FS: 00007fa70abdd6c0(0000) GS:ffff8882a9f2e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000010000 CR3: 0000000112fa8000 CR4: 00000000000006f0 ---------------- Code disassembly (best guess): 0: 5c pop %rsp 1: 24 08 and $0x8,%al 3: 4c 89 74 24 10 mov %r14,0x10(%rsp) 8: 48 8b 44 24 60 mov 0x60(%rsp),%rax d: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) 12: 74 08 je 0x1c 14: 48 89 df mov %rbx,%rdi 17: e8 42 15 21 f8 call 0xf821155e 1c: 48 8b 03 mov (%rbx),%rax 1f: 49 89 c6 mov %rax,%r14 22: 49 83 e6 fe and $0xfffffffffffffffe,%r14 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 4c 89 f7 mov %r14,%rdi 34: e8 25 15 21 f8 call 0xf821155e 39: bb 08 01 00 00 mov $0x108,%ebx 3e: 49 rex.WB 3f: 03 .byte 0x3