------------[ cut here ]------------ memcpy: detected field-spanning write (size 40) of single field "&top_iph->saddr" at net/ipv6/ah6.c:439 (size 16) WARNING: CPU: 0 PID: 8838 at net/ipv6/ah6.c:439 ah6_output+0xe7e/0x14e0 net/ipv6/ah6.c:439 Modules linked in: CPU: 0 UID: 0 PID: 8838 Comm: syz.1.814 Not tainted 6.15.0-rc6-syzkaller-00173-g9e89db3d847f #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:ah6_output+0xe7e/0x14e0 net/ipv6/ah6.c:439 Code: ff e8 36 80 9f f7 c6 05 bb 97 48 05 01 90 b9 10 00 00 00 48 c7 c7 a0 56 7e 8c 4c 89 fe 48 c7 c2 00 59 7e 8c e8 a3 dc 63 f7 90 <0f> 0b 90 90 e9 b5 fe ff ff e8 74 e4 35 01 48 8b 4c 24 10 80 e1 07 RSP: 0018:ffffc900049f70e0 EFLAGS: 00010246 RAX: 3fffcb5d3bcc7c00 RBX: 0000000000000028 RCX: 0000000000080000 RDX: ffffc9000ece1000 RSI: 00000000000052e8 RDI: 00000000000052e9 RBP: ffffc900049f7250 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff1bba944 R12: dffffc0000000000 R13: 1ffff9200093ee38 R14: ffff8881452e8800 R15: 0000000000000028 FS: 00007fc3a1d2c6c0(0000) GS:ffff8881260c7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555569628808 CR3: 000000005cf4e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: xfrm_output_one net/xfrm/xfrm_output.c:555 [inline] xfrm_output_resume+0x2c55/0x6170 net/xfrm/xfrm_output.c:590 __xfrm6_output+0x2eb/0x1070 net/ipv6/xfrm6_output.c:103 NF_HOOK_COND include/linux/netfilter.h:303 [inline] xfrm6_output+0x1c6/0x4f0 net/ipv6/xfrm6_output.c:108 ip6_send_skb+0x1d5/0x390 net/ipv6/ip6_output.c:1981 l2tp_ip6_sendmsg+0x1378/0x1870 net/l2tp/l2tp_ip6.c:661 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x19c/0x270 net/socket.c:727 ____sys_sendmsg+0x505/0x830 net/socket.c:2566 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2655 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc3a0f8e969 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:00007fc3a1d2c038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fc3a11b6080 RCX: 00007fc3a0f8e969 RDX: 0000000000000800 RSI: 0000200000000540 RDI: 0000000000000004 RBP: 00007fc3a1010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc3a11b6080 R15: 00007ffc18a80a58