[v5.15] INFO: rcu detected stall in security_file_ioctl

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4878aadf2d15 Linux 5.15.161
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=131d0682980000
kernel config: https://syzkaller.appspot.com/x/.config?x=875d98826c53bf16
dashboard link: https://syzkaller.appspot.com/bug?extid=c81c1accb780779cad42
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f227a150ea92/disk-4878aadf.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6cfc50bf8b4e/vmlinux-4878aadf.xz
kernel image: https://storage.googleapis.com/syzbot-assets/23f7adc3c761/bzImage-4878aadf.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c81c1a...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P1202/1:b..l P2962/1:b..l
(detected by 1, t=10502 jiffies, g=33509, q=150)
task:udevd state:R running task stack:22624 pid: 2962 ppid: 1 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
irqentry_exit+0x53/0x80 kernel/entry/common.c:432
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_release+0x62d/0x9a0 kernel/locking/lockdep.c:5647
Code: 3c 3b 00 74 08 4c 89 f7 e8 10 54 67 00 f6 84 24 91 00 00 00 02 75 6f 41 f7 c5 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 4b c7 44 27 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc900024c7880 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92000498f22 RCX: ffffc900024c7903
RDX: 0000000000000002 RSI: ffffffff8a8b3ca0 RDI: ffffffff8ad8f740
RBP: ffffc900024c79b8 R08: dffffc0000000000 R09: fffffbfff1bc8d86
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000498f1c
R13: 0000000000000246 R14: ffffc900024c7910 R15: dffffc0000000000
rcu_read_unlock include/linux/rcupdate.h:772 [inline]
prepend_path+0x60b/0xb70 fs/d_path.c:175
d_absolute_path+0x175/0x300 fs/d_path.c:235
tomoyo_get_absolute_path security/tomoyo/realpath.c:101 [inline]
tomoyo_realpath_from_path+0x2fd/0x5e0 security/tomoyo/realpath.c:276
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_number_perm+0x225/0x810 security/tomoyo/file.c:723
security_file_ioctl+0x6d/0xa0 security/security.c:1555
__do_sys_ioctl fs/ioctl.c:868 [inline]
__se_sys_ioctl+0x47/0x160 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f1e6975ad49
RSP: 002b:00007ffc39092a88 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1e6975ad49
RDX: 0000000000000000 RSI: 000000000000125f RDI: 000000000000000c
RBP: 000055c7015ba2c0 R08: 0000000000000008 R09: ee14eaeaee164c61
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc39092c68
R13: 000000000000000c R14: 000055c700401fee R15: 0000000000000000
</TASK>
task:kworker/u4:4 state:R running task stack:21568 pid: 1202 ppid: 2 flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
irqentry_exit+0x53/0x80 kernel/entry/common.c:432
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 0c 7e 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc90004b9f8e0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92000973f28 RCX: 1ffff92000973ec8
RDX: dffffc0000000000 RSI: ffffffff8a8b3ca0 RDI: ffffffff8ad8f740
RBP: ffffc90004b9fa40 R08: dffffc0000000000 R09: fffffbfff1f7f219
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000973f24
R13: dffffc0000000000 R14: ffffc90004b9f940 R15: 0000000000000246
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
rcu_read_lock include/linux/rcupdate.h:739 [inline]
batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:755 [inline]
batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:826 [inline]
batadv_iv_ogm_schedule+0x429/0x1000 net/batman-adv/bat_iv_ogm.c:869
batadv_iv_send_outstanding_bat_ogm_packet+0x6fa/0x800 net/batman-adv/bat_iv_ogm.c:1713
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
</TASK>
rcu: rcu_preempt kthread starved for 9922 jiffies! g33509 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt state:R running task stack:27064 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
</TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:570


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