------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 23014 at lib/refcount.c:28 refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28
Modules linked in:
CPU: 0 UID: 0 PID: 23014 Comm: syz.4.4045 Not tainted 6.14.0-rc1-syzkaller-00028-g5c8c229261f1 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28
Code: ff 89 de e8 98 2d fc fc 84 db 0f 85 66 ff ff ff e8 eb 32 fc fc c6 05 8f ad 8b 0b 01 90 48 c7 c7 60 87 d2 8b e8 07 0d bd fc 90 <0f> 0b 90 90 e9 43 ff ff ff e8 c8 32 fc fc 0f b6 1d 6a ad 8b 0b 31
RSP: 0018:ffffc90000007d90 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8179c889
RDX: ffff8880225e8000 RSI: ffffffff8179c896 RDI: 0000000000000001
RBP: ffff88806b02a778 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88806b02a778
R13: ffff88804eefb400 R14: 0000000000000015 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88802b400000(0063) knlGS:0000000057b99440
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000003241dffc CR3: 0000000072ccc000 CR4: 0000000000352ef0
Call Trace:
 <IRQ>
 __refcount_sub_and_test include/linux/refcount.h:275 [inline]
 __refcount_dec_and_test include/linux/refcount.h:307 [inline]
 refcount_dec_and_test include/linux/refcount.h:325 [inline]
 p9_req_put+0x1ec/0x250 net/9p/client.c:404
 req_done+0x1e7/0x2f0 net/9p/trans_virtio.c:147
 vring_interrupt drivers/virtio/virtio_ring.c:2715 [inline]
 vring_interrupt+0x31b/0x400 drivers/virtio/virtio_ring.c:2690
 __handle_irq_event_percpu+0x229/0x7d0 kernel/irq/handle.c:158
 handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
 handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210
 handle_edge_irq+0x263/0xd10 kernel/irq/chip.c:831
 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
 handle_irq arch/x86/kernel/irq.c:247 [inline]
 call_irq_handler arch/x86/kernel/irq.c:259 [inline]
 __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:285
 common_interrupt+0xba/0xe0 arch/x86/kernel/irq.c:278
 </IRQ>
 <TASK>
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 86 11 4d f6 48 89 df e8 ce 90 4d f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 b5 71 3e f6 65 8b 05 a6 cc ba 74 85 c0 74 16 5b
RSP: 0018:ffffc900262c7b78 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff888023718a10 RCX: 1ffffffff20bf291
RDX: 0000000000000000 RSI: ffffffff8b6ce5c0 RDI: ffffffff8bd2d220
RBP: 0000000000000206 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff905fd817 R11: ffffffff818b359e R12: ffff888023718014
R13: ffff888023718a10 R14: ffff888023718000 R15: ffffc900262c7bd8
 class_raw_spinlock_irqsave_destructor include/linux/spinlock.h:551 [inline]
 try_to_wake_up+0x949/0x1490 kernel/sched/core.c:4213
 wake_up_process kernel/sched/core.c:4462 [inline]
 wake_up_q+0x91/0x140 kernel/sched/core.c:1074
 futex_wake+0x43e/0x4e0 kernel/futex/waitwake.c:199
 do_futex+0x1e5/0x350 kernel/futex/syscalls.c:107
 __do_sys_futex_time32 kernel/futex/syscalls.c:509 [inline]
 __se_sys_futex_time32 kernel/futex/syscalls.c:492 [inline]
 __ia32_sys_futex_time32+0x1da/0x460 kernel/futex/syscalls.c:492
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7ff7579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000ffbbe6cc EFLAGS: 00000246 ORIG_RAX: 00000000000000f0
RAX: ffffffffffffffda RBX: 00000000f74b4f88 RCX: 0000000000000081
RDX: 00000000000f4240 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	f5                   	cmc
   1:	53                   	push   %rbx
   2:	48 8b 74 24 10       	mov    0x10(%rsp),%rsi
   7:	48 89 fb             	mov    %rdi,%rbx
   a:	48 83 c7 18          	add    $0x18,%rdi
   e:	e8 86 11 4d f6       	call   0xf64d1199
  13:	48 89 df             	mov    %rbx,%rdi
  16:	e8 ce 90 4d f6       	call   0xf64d90e9
  1b:	f7 c5 00 02 00 00    	test   $0x200,%ebp
  21:	75 23                	jne    0x46
  23:	9c                   	pushf
  24:	58                   	pop    %rax
  25:	f6 c4 02             	test   $0x2,%ah
  28:	75 37                	jne    0x61
* 2a:	bf 01 00 00 00       	mov    $0x1,%edi <-- trapping instruction
  2f:	e8 b5 71 3e f6       	call   0xf63e71e9
  34:	65 8b 05 a6 cc ba 74 	mov    %gs:0x74bacca6(%rip),%eax        # 0x74bacce1
  3b:	85 c0                	test   %eax,%eax
  3d:	74 16                	je     0x55
  3f:	5b                   	pop    %rbx