------------[ cut here ]------------
memcpy: detected field-spanning write (size 20) of single field "pfx->in6_u.u6_addr8" at ./include/net/ipv6.h:614 (size 16)
WARNING: CPU: 0 PID: 22047 at ./include/net/ipv6.h:614 ipv6_addr_prefix+0x124/0x1d0 include/net/ipv6.h:614
Modules linked in:
CPU: 0 UID: 0 PID: 22047 Comm: syz.0.3206 Not tainted 6.15.0-syzkaller-07774-g90b83efa6701 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:ipv6_addr_prefix+0x124/0x1d0 include/net/ipv6.h:614
Code: cc e8 e0 74 a6 f7 c6 05 a7 2d 71 05 01 90 b9 10 00 00 00 48 c7 c7 20 46 9e 8c 4c 89 fe 48 c7 c2 40 4d 9e 8c e8 1d 61 6a f7 90 <0f> 0b 90 90 e9 33 ff ff ff e8 ae 74 a6 f7 44 89 e6 48 c7 c7 80 80
RSP: 0018:ffffc9000b6beb30 EFLAGS: 00010246
RAX: 071aceab5c3d6d00 RBX: ffff88805b62cc50 RCX: 0000000000080000
RDX: ffffc900049d2000 RSI: 00000000000066a7 RDI: 00000000000066a8
RBP: 0000000000000007 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1bfa66c R12: 0000000000000014
R13: 1ffff920016d7d89 R14: ffffc9000b6bec64 R15: 0000000000000014
FS:  0000000000000000(0000) GS:ffff888125c66000(0063) knlGS:00000000f5066b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f7405008 CR3: 0000000032c80000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ip6_route_info_create+0x4af/0x860 net/ipv6/route.c:3793
 ip6_route_add+0x28/0x190 net/ipv6/route.c:3889
 addrconf_prefix_route+0x210/0x2c0 net/ipv6/addrconf.c:2487
 addrconf_prefix_rcv+0x60b/0x1610 net/ipv6/addrconf.c:2878
 ndisc_router_discovery+0x2015/0x35f0 net/ipv6/ndisc.c:1570
 icmpv6_rcv+0x139a/0x1c80 net/ipv6/icmp.c:988
 ip6_protocol_deliver_rcu+0xe0b/0x15c0 net/ipv6/ip6_input.c:436
 ip6_input_finish+0xde/0x190 net/ipv6/ip6_input.c:480
 NF_HOOK+0x309/0x3a0 include/linux/netfilter.h:317
 ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:491
 ip6_mc_input+0x79a/0xbe0 net/ipv6/ip6_input.c:588
 NF_HOOK+0x309/0x3a0 include/linux/netfilter.h:317
 __netif_receive_skb_one_core net/core/dev.c:5977 [inline]
 __netif_receive_skb+0xd3/0x380 net/core/dev.c:6090
 netif_receive_skb_internal net/core/dev.c:6176 [inline]
 netif_receive_skb+0x1cb/0x790 net/core/dev.c:6235
 tun_rx_batched+0x1b9/0x730 drivers/net/tun.c:1485
 tun_get_user+0x298e/0x3ce0 drivers/net/tun.c:1938
 tun_chr_write_iter+0x113/0x200 drivers/net/tun.c:1984
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x54b/0xa90 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb6/0x2b0 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f48539
Code: 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f5066520 EFLAGS: 00000206 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 00000000000000c8 RCX: 00000000800003c0
RDX: 0000000000000376 RSI: 00000000f73d2ff4 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	03 74 b4 01          	add    0x1(%rsp,%rsi,4),%esi
   4:	10 07                	adc    %al,(%rdi)
   6:	03 74 b0 01          	add    0x1(%rax,%rsi,4),%esi
   a:	10 08                	adc    %cl,(%rax)
   c:	03 74 d8 01          	add    0x1(%rax,%rbx,8),%esi
  20:	00 51 52             	add    %dl,0x52(%rcx)
  23:	55                   	push   %rbp
  24:	89 e5                	mov    %esp,%ebp
  26:	0f 34                	sysenter
  28:	cd 80                	int    $0x80
* 2a:	5d                   	pop    %rbp <-- trapping instruction
  2b:	5a                   	pop    %rdx
  2c:	59                   	pop    %rcx
  2d:	c3                   	ret
  2e:	90                   	nop
  2f:	90                   	nop
  30:	90                   	nop
  31:	90                   	nop
  32:	90                   	nop
  33:	90                   	nop
  34:	90                   	nop
  35:	90                   	nop
  36:	90                   	nop
  37:	90                   	nop
  38:	90                   	nop
  39:	90                   	nop
  3a:	90                   	nop
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop