------------[ cut here ]------------
WARNING: net/kcm/kcmsock.c:630 at kcm_write_msgs+0x13be/0x1570 net/kcm/kcmsock.c:630, CPU#0: syz-executor/6587
Modules linked in:
CPU: 0 UID: 0 PID: 6587 Comm: syz-executor Not tainted 6.16.0-rc5-next-20250708-syzkaller-07821-g58ba80c47402 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:kcm_write_msgs+0x13be/0x1570 net/kcm/kcmsock.c:630
Code: 24 60 49 89 06 45 31 e4 eb 68 e8 cd be 17 f7 e9 dc ed ff ff e8 c3 be 17 f7 45 31 e4 45 31 ed e9 cc ed ff ff e8 b3 be 17 f7 90 <0f> 0b 90 41 bc ea ff ff ff 48 bb 00 00 00 00 00 fc ff df eb 33 e8
RSP: 0018:ffffc9000405f6e0 EFLAGS: 00010293
RAX: ffffffff8aa7ed7d RBX: 0000000000000180 RCX: ffff888034760000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000405f8b0 R08: ffffc9000405f827 R09: 0000000000000000
R10: ffffc9000405f7c0 R11: fffff5200080bf05 R12: dffffc0000000000
R13: ffff888024c002c0 R14: ffff888032a1e700 R15: 0000000000000000
FS:  00007f886937a6c0(0000) GS:ffff888125bd7000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002011a000 CR3: 00000000324c6000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 kcm_sendmsg+0x24d5/0x2aa0 net/kcm/kcmsock.c:907
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:729
 sock_write_iter+0x258/0x330 net/socket.c:1179
 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_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f886867cee9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f886937a0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f88687abf80 RCX: 00007f886867cee9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 00007f88686c949e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f88687abf80 R15: 00007ffe278db2f8
 </TASK>