------------[ cut here ]------------ 'send_pkt()' returns 0, but 4096 expected WARNING: net/vmw_vsock/virtio_transport_common.c:430 at virtio_transport_send_pkt_info+0xd1e/0xef0 net/vmw_vsock/virtio_transport_common.c:428, CPU#1: syz.0.17/5986 Modules linked in: CPU: 1 UID: 0 PID: 5986 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:virtio_transport_send_pkt_info+0xd1e/0xef0 net/vmw_vsock/virtio_transport_common.c:428 Code: f6 90 0f 0b 90 e9 d7 f7 ff ff e8 5d cc 7c f6 c6 05 c6 5f 64 04 01 90 48 c7 c7 60 da b4 8c 44 89 f6 48 89 ea e8 13 eb 3e f6 90 <0f> 0b 90 90 eb 9e 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 0a f3 ff ff RSP: 0018:ffffc900033a7508 EFLAGS: 00010246 RAX: 2383e4149a9d5400 RBX: 0000000000001000 RCX: ffff88807b361e80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002 RBP: 0000000000001000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff1c3a720 R12: 0000000000040000 R13: dffffc0000000000 R14: 0000000000000000 R15: ffffc900033a7640 FS: 00005555677a5500(0000) GS:ffff888125b6f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000030000 CR3: 0000000075f06000 CR4: 00000000003526f0 Call Trace: virtio_transport_stream_enqueue net/vmw_vsock/virtio_transport_common.c:1113 [inline] virtio_transport_seqpacket_enqueue+0x143/0x1c0 net/vmw_vsock/virtio_transport_common.c:841 vsock_connectible_sendmsg+0xabf/0x1040 net/vmw_vsock/af_vsock.c:2158 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:746 ____sys_sendmsg+0x52d/0x870 net/socket.c:2634 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2688 __sys_sendmmsg+0x227/0x430 net/socket.c:2777 __do_sys_sendmmsg net/socket.c:2804 [inline] __se_sys_sendmmsg net/socket.c:2801 [inline] __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2801 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1e5218f749 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:00007fffbe398ef8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f1e523e5fa0 RCX: 00007f1e5218f749 RDX: 0000000000000001 RSI: 0000200000000100 RDI: 0000000000000004 RBP: 00007f1e52213f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000024008094 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1e523e5fa0 R14: 00007f1e523e5fa0 R15: 0000000000000004