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general protection fault, probably for non-canonical address 0xdffffc000000005c: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000002e0-0x00000000000002e7]
CPU: 1 PID: 8239 Comm: syz.5.2590 Not tainted 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:ffffc90000d56bd8 EFLAGS: 00010206
RAX: 000000000000005c RBX: 00000000000002e0 RCX: 0000000000080000
RDX: ffff888119960000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000d56c58 R08: ffffffff842be13f R09: ffffc90000d56fb0
R10: ffffc90000d56fa0 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff110210b9244 R14: 0000000000000000 R15: 0000000000000002
FS:  00007f476c4346c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f476c433f98 CR3: 000000011432f000 CR4: 00000000003506a0
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: 0033:0x7f476ddc8c1f
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:00007f476c434000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f476dfe2fa0 RCX: 00007f476ddc8c1f
RDX: 000000000000004e RSI: 0000200000000000 RDI: 00000000000000c8
RBP: 00007f476de4b2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000004e R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f476dfe2fa0 R15: 00007fff9bd33148
Modules linked in:
---[ end trace 555beebeaff4ec46 ]---
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:ffffc90000d56bd8 EFLAGS: 00010206
RAX: 000000000000005c RBX: 00000000000002e0 RCX: 0000000000080000
RDX: ffff888119960000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000d56c58 R08: ffffffff842be13f R09: ffffc90000d56fb0
R10: ffffc90000d56fa0 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff110210b9244 R14: 0000000000000000 R15: 0000000000000002
FS:  00007f476c4346c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f476c433f98 CR3: 000000011432f000 CR4: 00000000003506a0
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