netlink: 4 bytes leftover after parsing attributes in process `syz.1.1937'. ------------[ cut here ]------------ !rwb WARNING: block/blk-wbt.c:784 at wbt_init_enable_default+0x148/0x1a0 block/blk-wbt.c:784, CPU#1: syz.1.1937/13040 Modules linked in: CPU: 1 UID: 0 PID: 13040 Comm: syz.1.1937 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:wbt_init_enable_default+0x148/0x1a0 block/blk-wbt.c:784 Code: 41 5c 41 5d 41 5e 41 5f 5d e9 64 47 0f 07 e8 8f 90 25 fd eb 18 e8 88 90 25 fd eb 0d e8 81 90 25 fd 4c 89 ff e8 69 a1 83 fd 90 <0f> 0b 90 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc RSP: 0000:ffffc9000c9bee08 EFLAGS: 00010292 RAX: fb138d9b21d77300 RBX: 1ffff1100f971604 RCX: 0000000000000046 RDX: 0000000000000006 RSI: ffffffff8def38f2 RDI: ffffffff8c27ab00 RBP: dffffc0000000000 R08: ffffffff901195b7 R09: 1ffffffff20232b6 R10: dffffc0000000000 R11: fffffbfff20232b7 R12: ffff88807cb8b020 R13: 0000000000000000 R14: ffff888029093000 R15: ffff88807cb8b000 FS: 00007f7659dd56c0(0000) GS:ffff888125560000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555650969e8 CR3: 000000005a4de000 CR4: 00000000003526f0 Call Trace: blk_register_queue+0x36a/0x3f0 block/blk-sysfs.c:942 __add_disk+0x677/0xd50 block/genhd.c:528 add_disk_fwnode+0xfb/0x480 block/genhd.c:597 add_disk include/linux/blkdev.h:785 [inline] nbd_dev_add+0x72c/0xb50 drivers/block/nbd.c:1984 nbd_genl_connect+0x962/0x1cf0 drivers/block/nbd.c:2125 genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec+0x18f/0x1d0 net/socket.c:737 __sock_sendmsg net/socket.c:752 [inline] ____sys_sendmsg+0x589/0x8c0 net/socket.c:2610 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2664 __sys_sendmsg net/socket.c:2696 [inline] __do_sys_sendmsg net/socket.c:2701 [inline] __se_sys_sendmsg net/socket.c:2699 [inline] __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2699 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f765bb9bf79 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7659dd5028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f765be16090 RCX: 00007f765bb9bf79 RDX: 0000000000000004 RSI: 0000200000000240 RDI: 0000000000000006 RBP: 00007f765bc327e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f765be16128 R14: 00007f765be16090 R15: 00007fff53230cb8