syzbot

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: 6881 Comm: syz.5.2269 Not tainted 5.10.239-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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+0xa7/0xd60 net/ipv6/route.c:739
Code: 41 80 7c 05 00 00 74 08 4c 89 f7 e8 53 fb a7 fd 41 bc e0 02 00 00 4d 03 26 4c 89 e0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 e7 e8 2b fb a7 fd 4d 8b 24 24 4d 85 e4 0f
RSP: 0018:ffffc90000b66db0 EFLAGS: 00010206
RAX: 000000000000005c RBX: 0000000000000003 RCX: dffffc0000000000
RDX: ffff888118fa4f00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000b66e38 R08: ffffc90000b67160 R09: ffffc90000b67170
R10: fffff5200016ce4e R11: 1ffff9200016ce4a R12: 00000000000002e0
R13: 1ffff11023bb0104 R14: ffff88811dd80820 R15: 0000000000000000
FS:  00007fe0055656c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000b63fe4 CR3: 000000012bcc4000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 rt6_nh_find_match+0xd9/0x140 net/ipv6/route.c:779
 nexthop_for_each_fib6_nh+0xf6/0x1e0 net/ipv4/nexthop.c:602
 __find_rr_leaf+0x50f/0x900 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+0x2f4/0x9f0 net/ipv6/route.c:2190
 ip6_pol_route+0x145/0x1110 net/ipv6/route.c:2226
 ip6_pol_route_output+0x51/0x80 net/ipv6/route.c:2475
 pol_lookup_func include/net/ip6_fib.h:594 [inline]
 fib6_rule_lookup+0x2ef/0x560 net/ipv6/fib6_rules.c:120
 ip6_route_output_flags_noref+0x248/0x2f0 net/ipv6/route.c:2507
 ip6_route_output_flags+0x3c/0x200 net/ipv6/route.c:2520
 ip6_route_output include/net/ip6_route.h:98 [inline]
 ip6_dst_lookup_tail+0x6d1/0x1210 net/ipv6/ip6_output.c:1090
 ip6_dst_lookup_flow+0x49/0xc0 net/ipv6/ip6_output.c:1220
 tcp_v6_connect+0x8be/0x1990 net/ipv6/tcp_ipv6.c:286
 __inet_stream_connect+0x276/0xd70 net/ipv4/af_inet.c:671
 tcp_sendmsg_fastopen+0x389/0x5c0 net/ipv4/tcp.c:1173
 tcp_sendmsg_locked+0x3235/0x3750 net/ipv4/tcp.c:1215
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1444
 inet6_sendmsg+0xa5/0xc0 net/ipv6/af_inet6.c:663
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 __sys_sendto+0x41d/0x580 net/socket.c:2006
 __do_sys_sendto net/socket.c:2018 [inline]
 __se_sys_sendto net/socket.c:2014 [inline]
 __x64_sys_sendto+0xe5/0x100 net/socket.c:2014
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fe006f3e9a9
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:00007fe005565038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fe007166160 RCX: 00007fe006f3e9a9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 00007fe006fc0ca1 R08: 0000200000b63fe4 R09: 000000000000001c
R10: 0000000020000841 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe007166160 R15: 00007fff42b2a5c8
Modules linked in:
---[ end trace 83402af3d3c7eb5f ]---
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+0xa7/0xd60 net/ipv6/route.c:739
Code: 41 80 7c 05 00 00 74 08 4c 89 f7 e8 53 fb a7 fd 41 bc e0 02 00 00 4d 03 26 4c 89 e0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 e7 e8 2b fb a7 fd 4d 8b 24 24 4d 85 e4 0f
RSP: 0018:ffffc90000b66db0 EFLAGS: 00010206
RAX: 000000000000005c RBX: 0000000000000003 RCX: dffffc0000000000
RDX: ffff888118fa4f00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000b66e38 R08: ffffc90000b67160 R09: ffffc90000b67170
R10: fffff5200016ce4e R11: 1ffff9200016ce4a R12: 00000000000002e0
R13: 1ffff11023bb0104 R14: ffff88811dd80820 R15: 0000000000000000
FS:  00007fe0055656c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d10fff8 CR3: 000000012bcc4000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	41 80 7c 05 00 00    	cmpb   $0x0,0x0(%r13,%rax,1)
   6:	74 08                	je     0x10
   8:	4c 89 f7             	mov    %r14,%rdi
   b:	e8 53 fb a7 fd       	call   0xfda7fb63
  10:	41 bc e0 02 00 00    	mov    $0x2e0,%r12d
  16:	4d 03 26             	add    (%r14),%r12
  19:	4c 89 e0             	mov    %r12,%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:	4c 89 e7             	mov    %r12,%rdi
  33:	e8 2b fb a7 fd       	call   0xfda7fb63
  38:	4d 8b 24 24          	mov    (%r12),%r12
  3c:	4d 85 e4             	test   %r12,%r12
  3f:	0f                   	.byte 0xf