------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 1 PID: 20 at lib/refcount.c:28 refcount_warn_saturate+0x14e/0x1a0 lib/refcount.c:28 Modules linked in: CPU: 1 PID: 20 Comm: ksoftirqd/1 Not tainted 5.15.179-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 80 bd f9 8a e8 be 14 38 fd 0f 0b eb 8d e8 a5 7f 6c fd c6 05 b1 e7 e2 09 01 48 c7 c7 e0 bd f9 8a e8 a2 14 38 fd <0f> 0b e9 6e ff ff ff e8 86 7f 6c fd c6 05 93 e7 e2 09 01 48 c7 c7 RSP: 0018:ffffc90000da7c80 EFLAGS: 00010246 RAX: 30ca1c837d308d00 RBX: 0000000000000003 RCX: ffff88813fe20000 RDX: 0000000000000100 RSI: 0000000000000100 RDI: 0000000000000000 RBP: 0000000000000003 R08: ffffffff8166be4c R09: fffff520001b4ed1 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000004 R13: ffffffff8c80a0e0 R14: 0000000000000000 R15: ffff8880216f3200 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f444a49af98 CR3: 000000005dcbf000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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