general protection fault, probably for non-canonical address 0xdffffc000000005c: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x00000000000002e0-0x00000000000002e7] CPU: 0 PID: 4895 Comm: syz.2.1001 Tainted: G W 5.10.234-syzkaller-00033-g094fc3778d6b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:__in6_dev_get include/net/addrconf.h:343 [inline] RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:434 [inline] RIP: 0010:find_match+0xaa/0xd70 net/ipv6/route.c:739 Code: 00 00 00 00 00 fc ff df 43 80 7c 25 00 00 74 08 48 89 df e8 18 7d 7c fd 48 89 d8 bb e0 02 00 00 48 03 18 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 f7 7c 7c fd 4c 8b 23 4d 85 e4 0f RSP: 0018:ffffc90001d86bd8 EFLAGS: 00010206 RAX: 000000000000005c RBX: 00000000000002e0 RCX: 0000000000080000 RDX: ffff8881427613c0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90001d86c58 R08: ffffffff842be13f R09: ffffc90001d86fb0 R10: ffffc90001d86fa0 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff110249c5324 R14: 0000000000000000 R15: 0000000000000002 FS: 00007f1fe40b56c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1fe40b4f98 CR3: 0000000114296000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rt6_nh_find_match+0xdd/0x140 net/ipv6/route.c:779 nexthop_for_each_fib6_nh+0x113/0x210 net/ipv4/nexthop.c:602 __find_rr_leaf+0x658/0xb70 net/ipv6/route.c:820 find_rr_leaf net/ipv6/route.c:848 [inline] rt6_select net/ipv6/route.c:892 [inline] fib6_table_lookup+0x338/0xaf0 net/ipv6/route.c:2190 ip6_pol_route+0x151/0x14b0 net/ipv6/route.c:2226 ip6_pol_route_input+0x55/0x80 net/ipv6/route.c:2284 pol_lookup_func include/net/ip6_fib.h:594 [inline] fib6_rule_lookup+0x371/0x620 net/ipv6/fib6_rules.c:120 ip6_route_input_lookup net/ipv6/route.c:2296 [inline] ip6_route_input+0x726/0xb00 net/ipv6/route.c:2465 ip6_rcv_finish_core net/ipv6/ip6_input.c:67 [inline] ip6_rcv_finish+0x14f/0x350 net/ipv6/ip6_input.c:78 NF_HOOK include/linux/netfilter.h:299 [inline] ipv6_rcv+0xee/0x270 net/ipv6/ip6_input.c:301 __netif_receive_skb_one_core net/core/dev.c:5401 [inline] __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5515 netif_receive_skb_internal net/core/dev.c:5620 [inline] netif_receive_skb+0xb0/0x480 net/core/dev.c:5679 tun_rx_batched+0x6d9/0x870 drivers/net/tun.c:-1 tun_get_user+0x2bf3/0x38f0 drivers/net/tun.c:2026 tun_chr_write_iter+0x1a8/0x250 drivers/net/tun.c:2059 call_write_iter include/linux/fs.h:2058 [inline] new_sync_write fs/read_write.c:518 [inline] vfs_write+0xb4c/0xe70 fs/read_write.c:605 ksys_write+0x199/0x2c0 fs/read_write.c:658 __do_sys_write fs/read_write.c:670 [inline] __se_sys_write fs/read_write.c:667 [inline] __x64_sys_write+0x7b/0x90 fs/read_write.c:667 do_syscall_64+0x34/0x70 arch/x86/entry/common.c:-1 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f1fe5a49c1f Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007f1fe40b5000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f1fe5c63fa0 RCX: 00007f1fe5a49c1f RDX: 000000000000004e RSI: 0000200000000000 RDI: 00000000000000c8 RBP: 00007f1fe5acc2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000004e R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f1fe5c63fa0 R15: 00007ffe73fcb718 Modules linked in: ---[ end trace 374cbeb3f7e7bf72 ]--- RIP: 0010:__in6_dev_get include/net/addrconf.h:343 [inline] RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:434 [inline] RIP: 0010:find_match+0xaa/0xd70 net/ipv6/route.c:739 Code: 00 00 00 00 00 fc ff df 43 80 7c 25 00 00 74 08 48 89 df e8 18 7d 7c fd 48 89 d8 bb e0 02 00 00 48 03 18 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 f7 7c 7c fd 4c 8b 23 4d 85 e4 0f RSP: 0018:ffffc90001d86bd8 EFLAGS: 00010206 RAX: 000000000000005c RBX: 00000000000002e0 RCX: 0000000000080000 RDX: ffff8881427613c0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90001d86c58 R08: ffffffff842be13f R09: ffffc90001d86fb0 R10: ffffc90001d86fa0 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff110249c5324 R14: 0000000000000000 R15: 0000000000000002 FS: 00007f1fe40b56c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1fe40b4f98 CR3: 0000000114296000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 7 bytes skipped: 0: df 43 80 filds -0x80(%rbx) 3: 7c 25 jl 0x2a 5: 00 00 add %al,(%rax) 7: 74 08 je 0x11 9: 48 89 df mov %rbx,%rdi c: e8 18 7d 7c fd call 0xfd7c7d29 11: 48 89 d8 mov %rbx,%rax 14: bb e0 02 00 00 mov $0x2e0,%ebx 19: 48 03 18 add (%rax),%rbx 1c: 48 89 d8 mov %rbx,%rax 1f: 48 c1 e8 03 shr $0x3,%rax * 23: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction 28: 74 08 je 0x32 2a: 48 89 df mov %rbx,%rdi 2d: e8 f7 7c 7c fd call 0xfd7c7d29 32: 4c 8b 23 mov (%rbx),%r12 35: 4d 85 e4 test %r12,%r12 38: 0f .byte 0xf