------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 5941 at lib/refcount.c:28 refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28
Modules linked in:
CPU: 0 UID: 0 PID: 5941 Comm: syz-executor Not tainted 6.15.0-rc6-syzkaller-00208-g3c21441eeffc #0 PREEMPT(full)
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 58 db ec fc 84 db 0f 85 66 ff ff ff e8 6b e0 ec fc c6 05 a1 b9 9f 0b 01 90 48 c7 c7 60 20 f4 8b e8 47 c3 ac fc 90 <0f> 0b 90 90 e9 43 ff ff ff e8 48 e0 ec fc 0f b6 1d 7c b9 9f 0b 31
RSP: 0018:ffffc90000007be8 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff817a94a8
RDX: ffff888024092440 RSI: ffffffff817a94b5 RDI: 0000000000000001
RBP: ffff88804dd7f878 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88804dd7f878
R13: ffff88801e037c00 R14: 0000000000000015 R15: 1ffff11003b6000c
FS: 0000000000000000(0000) GS:ffff8880977e9000(0063) knlGS:0000000056b84440
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f7f155c0 CR3: 00000000661c7000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__refcount_sub_and_test include/linux/refcount.h:400 [inline]
__refcount_dec_and_test include/linux/refcount.h:432 [inline]
refcount_dec_and_test include/linux/refcount.h:450 [inline]
p9_req_put+0x1ec/0x250 net/9p/client.c:404
req_done+0x1dc/0x2e0 net/9p/trans_virtio.c:147
vring_interrupt drivers/virtio/virtio_ring.c:2715 [inline]
vring_interrupt+0x31e/0x400 drivers/virtio/virtio_ring.c:2690
__handle_irq_event_percpu+0x22c/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:254 [inline]
call_irq_handler arch/x86/kernel/irq.c:266 [inline]
__common_interrupt+0xe2/0x250 arch/x86/kernel/irq.c:292
common_interrupt+0x61/0xe0 arch/x86/kernel/irq.c:285
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
RIP: 0010:handle_softirqs+0x1dd/0x8e0 kernel/softirq.c:565
Code: 88 6c 24 26 4c 89 7c 24 18 48 c7 c7 a0 87 8b 8b e8 98 01 ed 09 65 66 c7 05 36 e5 26 12 00 00 e8 89 e8 45 00 fb bb ff ff ff ff <49> c7 c7 c0 c0 00 8e 41 0f bc dc 83 c3 01 0f 85 a4 00 00 00 e9 b1
RSP: 0018:ffffc90000007f28 EFLAGS: 00000206
RAX: 0000000000355efa RBX: 00000000ffffffff RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8dbdcd2f RDI: ffffffff8bf47460
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90851f17 R11: 0000000000000000 R12: 0000000000000082
R13: 000000000000000a R14: 1ffff92000000fed R15: ffffed1004812488
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__copy_present_ptes mm/memory.c:954 [inline]
RIP: 0010:copy_present_ptes mm/memory.c:1044 [inline]
RIP: 0010:copy_pte_range mm/memory.c:1167 [inline]
RIP: 0010:copy_pmd_range mm/memory.c:1255 [inline]
RIP: 0010:copy_pud_range mm/memory.c:1292 [inline]
RIP: 0010:copy_p4d_range mm/memory.c:1316 [inline]
RIP: 0010:copy_page_range+0x1729/0x5f80 mm/memory.c:1410
Code: 8b 44 24 08 bf 20 00 00 00 48 8b 58 20 48 89 dd 83 e5 28 48 89 ee e8 f6 f0 b3 ff 48 83 fd 20 0f 84 3b 16 00 00 e8 77 f5 b3 ff <83> e3 08 31 ff 48 89 de e8 da f0 b3 ff 48 85 db 74 14 e8 60 f5 b3
RSP: 0018:ffffc90003a3f760 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 00000000180400fb RCX: ffffffff8206ba9a
RDX: ffff888024092440 RSI: ffffffff8206baa9 RDI: 0000000000000007
RBP: 0000000000000028 R08: 0000000000000007 R09: 0000000000000020
R10: 0000000000000028 R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff8880661d4b60 R15: ffffea000133fd40
dup_mmap kernel/fork.c:726 [inline]
dup_mm kernel/fork.c:1734 [inline]
copy_mm kernel/fork.c:1786 [inline]
copy_process+0x862b/0x91a0 kernel/fork.c:2429
kernel_clone+0xfc/0x960 kernel/fork.c:2844
__do_compat_sys_ia32_clone+0xcb/0x110 arch/x86/kernel/sys_ia32.c:254
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0x73/0x120 arch/x86/entry/syscall_32.c:306
do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf704e579
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:00000000fff9fa5c EFLAGS: 00000292 ORIG_RAX: 0000000000000078
RAX: ffffffffffffffda RBX: 0000000001200011 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000056b844a8
RBP: 00000000f73b2ff4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
----------------
Code disassembly (best guess):
0: 88 6c 24 26 mov %ch,0x26(%rsp)
4: 4c 89 7c 24 18 mov %r15,0x18(%rsp)
9: 48 c7 c7 a0 87 8b 8b mov $0xffffffff8b8b87a0,%rdi
10: e8 98 01 ed 09 call 0x9ed01ad
15: 65 66 c7 05 36 e5 26 movw $0x0,%gs:0x1226e536(%rip) # 0x1226e555
1c: 12 00 00
1f: e8 89 e8 45 00 call 0x45e8ad
24: fb sti
25: bb ff ff ff ff mov $0xffffffff,%ebx
* 2a: 49 c7 c7 c0 c0 00 8e mov $0xffffffff8e00c0c0,%r15 <-- trapping instruction
31: 41 0f bc dc bsf %r12d,%ebx
35: 83 c3 01 add $0x1,%ebx
38: 0f 85 a4 00 00 00 jne 0xe2
3e: e9 .byte 0xe9
3f: b1 .byte 0xb1