syzbot


WARNING: refcount bug in call_timer_fn (2)

Status: auto-obsoleted due to no activity on 2024/11/03 21:47
Subsystems: acpi
[Documentation on labels]
Reported-by: syzbot+9a24ebb6230fdd1780bd@syzkaller.appspotmail.com
First crash: 104d, last: 104d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING: refcount bug in call_timer_fn net 1 1078d 1078d 0/28 closed as invalid on 2022/01/07 18:56
upstream WARNING: refcount bug in call_timer_fn (3) fs 1 10d 6d08h 0/28 moderation: reported on 2024/11/11 18:37
linux-6.1 WARNING: refcount bug in call_timer_fn 1 261d 261d 0/3 auto-obsoleted due to no activity on 2024/06/09 18:08

Sample crash report:
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 0 at lib/refcount.c:28 refcount_warn_saturate+0x15a/0x1d0 lib/refcount.c:28
Modules linked in:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.11.0-rc1-syzkaller-00168-g7ab107544b77 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:refcount_warn_saturate+0x15a/0x1d0 lib/refcount.c:28
Code: 80 09 60 8c e8 57 68 a5 fc 90 0f 0b 90 90 eb 99 e8 5b 3e e3 fc c6 05 c6 5b 51 0b 01 90 48 c7 c7 e0 09 60 8c e8 37 68 a5 fc 90 <0f> 0b 90 90 e9 76 ff ff ff e8 38 3e e3 fc c6 05 a0 5b 51 0b 01 90
RSP: 0018:ffffc90000007ba8 EFLAGS: 00010246
RAX: 1f7c923a8b17e600 RBX: ffff8880640f9020 RCX: ffffffff8e694680
RDX: 0000000000000101 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000003 R08: ffffffff815592f2 R09: fffffbfff1cf9f80
R10: dffffc0000000000 R11: fffffbfff1cf9f80 R12: 1ffff92000000f7c
R13: ffff8880640f91b8 R14: 0000000000000001 R15: 0000000000000101
FS:  0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000045b3a000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792
 expire_timers kernel/time/timer.c:1843 [inline]
 __run_timers kernel/time/timer.c:2417 [inline]
 __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428
 run_timer_base kernel/time/timer.c:2437 [inline]
 run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447
 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
 __do_softirq kernel/softirq.c:588 [inline]
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline]
RIP: 0010:acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112
Code: 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 40 d7 03 00 48 f7 00 08 00 00 00 75 10 66 90 0f 00 2d e5 63 b4 00 f3 0f 1e fa fb f4 <fa> c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90
RSP: 0018:ffffffff8e607ca8 EFLAGS: 00000246
RAX: ffffffff8e694680 RBX: ffff88801c294064 RCX: 00000000000453f1
RDX: 0000000000000001 RSI: ffff88801c294000 RDI: ffff88801c294064
RBP: 000000000003a6b8 R08: ffff8880b9237c7b R09: 1ffff11017246f8f
R10: dffffc0000000000 R11: ffffffff8bb5a790 R12: ffff88801b7eb800
R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8f0db3e0
 acpi_idle_enter+0xe4/0x140 drivers/acpi/processor_idle.c:702
 cpuidle_enter_state+0x112/0x480 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x5d/0xa0 drivers/cpuidle/cpuidle.c:388
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:230 [inline]
 do_idle+0x375/0x5d0 kernel/sched/idle.c:326
 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:424
 rest_init+0x2dc/0x300 init/main.c:747
 start_kernel+0x47a/0x500 init/main.c:1103
 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507
 x86_64_start_kernel+0x9f/0xa0 arch/x86/kernel/head64.c:488
 common_startup_64+0x13e/0x147
 </TASK>
----------------
Code disassembly (best guess):
   0:	90                   	nop
   1:	90                   	nop
   2:	90                   	nop
   3:	90                   	nop
   4:	90                   	nop
   5:	90                   	nop
   6:	90                   	nop
   7:	90                   	nop
   8:	90                   	nop
   9:	65 48 8b 04 25 40 d7 	mov    %gs:0x3d740,%rax
  10:	03 00
  12:	48 f7 00 08 00 00 00 	testq  $0x8,(%rax)
  19:	75 10                	jne    0x2b
  1b:	66 90                	xchg   %ax,%ax
  1d:	0f 00 2d e5 63 b4 00 	verw   0xb463e5(%rip)        # 0xb46409
  24:	f3 0f 1e fa          	endbr64
  28:	fb                   	sti
  29:	f4                   	hlt
* 2a:	fa                   	cli <-- trapping instruction
  2b:	c3                   	ret
  2c:	cc                   	int3
  2d:	cc                   	int3
  2e:	cc                   	int3
  2f:	cc                   	int3
  30:	66 0f 1f 84 00 00 00 	nopw   0x0(%rax,%rax,1)
  37:	00 00
  39:	90                   	nop
  3a:	90                   	nop
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/05 21:47 net 7ab107544b77 e35c337f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: refcount bug in call_timer_fn
* Struck through repros no longer work on HEAD.