blk_update_request: I/O error, dev nbd1, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 14 at lib/refcount.c:28 refcount_warn_saturate+0x14e/0x1a0 lib/refcount.c:28
Modules linked in:
CPU: 0 PID: 14 Comm: ksoftirqd/0 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:refcount_warn_saturate+0x14e/0x1a0 lib/refcount.c:28
Code: 09 01 48 c7 c7 c0 b5 f9 8a e8 2e 42 38 fd 0f 0b eb 8d e8 85 a8 6c fd c6 05 cb 10 e3 09 01 48 c7 c7 20 b6 f9 8a e8 12 42 38 fd <0f> 0b e9 6e ff ff ff e8 66 a8 6c fd c6 05 ad 10 e3 09 01 48 c7 c7
RSP: 0018:ffffc90000d37c80 EFLAGS: 00010246
RAX: cbb97448cdc38000 RBX: 0000000000000003 RCX: ffff88813ff21dc0
RDX: 0000000000000100 RSI: 0000000000000100 RDI: 0000000000000000
RBP: 0000000000000003 R08: ffffffff8166aa8c R09: fffffbfff1c150ee
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000004
R13: ffffffff8c80a0e0 R14: 0000000000000000 R15: ffff888021d38200
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30318ff8 CR3: 00000000246bf000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 blk_complete_reqs block/blk-mq.c:587 [inline]
 blk_done_softirq+0xf2/0x130 block/blk-mq.c:592
 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558
 run_ksoftirqd+0xc6/0x120 kernel/softirq.c:925
 smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>