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INFO: rcu detected stall in security_file_ioctl

Status: upstream: reported C repro on 2024/02/20 18:28
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+0e21429a9aacc1a8de3f@syzkaller.appspotmail.com
First crash: 634d, last: 4h06m
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2024/02/20 upstream (ToT) b401b621758e C [report] INFO: rcu detected stall in corrupted
▶ ▼ Similar bugs (11)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in security_file_ioctl mm 1 7 2173d 2175d 0/29 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in security_file_ioctl (2) mm 1 6 2139d 2139d 0/29 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in security_file_ioctl (7) mm 1 1 727d 727d 0/29 auto-obsoleted due to no activity on 2024/02/17 10:34
upstream INFO: rcu detected stall in security_file_ioctl (4) tomoyo 1 1 1949d 1949d 0/29 auto-closed as invalid on 2020/10/13 12:41
linux-5.15 INFO: rcu detected stall in security_file_ioctl missing-backport origin:upstream 1 syz done 5 37d 508d 0/3 upstream: reported syz repro on 2024/06/25 09:44
upstream INFO: rcu detected stall in security_file_ioctl (8) tomoyo 1 C error done 8 502d 541d 26/29 fixed on 2024/08/06 16:46
upstream INFO: rcu detected stall in security_file_ioctl (6) kernel 1 1 1300d 1300d 0/29 auto-closed as invalid on 2022/06/24 22:52
upstream INFO: rcu detected stall in security_file_ioctl (3) mm 1 4 2138d 2138d 0/29 closed as invalid on 2020/01/09 08:13
linux-6.6 INFO: rcu detected stall in security_file_ioctl 1 1 86d 86d 0/2 upstream: reported on 2025/08/21 08:01
upstream INFO: rcu detected stall in security_file_ioctl (5) tomoyo 1 9 1396d 1635d 0/29 closed as invalid on 2022/02/08 10:00
upstream INFO: rcu detected stall in security_file_ioctl (9) mm 1 syz error 96 5d11h 359d 0/29 upstream: reported syz repro on 2024/11/22 01:19
▶ ▼ Fix bisection attempts (13)
Created Duration User Patch Repo Result
2025/05/26 20:54 1h24m bisect fix linux-6.1.y error job log
2025/04/23 02:33 1h39m bisect fix linux-6.1.y OK (0) job log log
2025/03/19 20:13 3h08m bisect fix linux-6.1.y OK (0) job log log
2025/02/16 14:07 1h31m bisect fix linux-6.1.y OK (0) job log log
2025/01/16 22:32 1h21m bisect fix linux-6.1.y OK (0) job log log
2024/12/02 18:26 2h23m bisect fix linux-6.1.y OK (0) job log log
2024/10/23 08:50 1h43m bisect fix linux-6.1.y OK (0) job log log
2024/09/21 00:24 2h27m bisect fix linux-6.1.y OK (0) job log log
2024/08/17 21:18 1h21m bisect fix linux-6.1.y OK (0) job log log
2024/07/06 09:13 2h06m bisect fix linux-6.1.y OK (0) job log log
2024/05/27 17:00 1h18m bisect fix linux-6.1.y OK (0) job log log
2024/04/22 09:14 3h25m bisect fix linux-6.1.y OK (0) job log log
2024/03/22 04:03 1h29m bisect fix linux-6.1.y OK (0) job log log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4272/2:b..l
	(detected by 1, t=10502 jiffies, g=7913, q=129 ncpus=2)
task:syz-executor110 state:R  running task     stack:24864 pid:4272  ppid:4268   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc90003c574c0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 2002b0e278a67100
RDX: 0000000000000000 RSI: ffffffff8a8c1680 RDI: ffffffff8adefd20
RBP: ffffc90003c575d8 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: 0000000000000001
R13: 1ffff9200078aea4 R14: 0000000000000246 R15: dffffc0000000000
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 is_bpf_text_address+0x43/0x2a0 kernel/bpf/core.c:735
 kernel_text_address+0x9c/0xd0 kernel/extable.c:125
 __kernel_text_address+0x9/0x30 kernel/extable.c:79
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
 save_stack+0xf3/0x1e0 mm/page_owner.c:127
 __reset_page_owner+0x51/0x1a0 mm/page_owner.c:148
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1459 [inline]
 free_pcp_prepare mm/page_alloc.c:1509 [inline]
 free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384
 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 __kmem_cache_alloc_node+0x140/0x260 mm/slub.c:3398
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa0/0x240 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 tomoyo_realpath_from_path+0xdf/0x5d0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_number_perm+0x1e3/0x600 security/tomoyo/file.c:723
 security_file_ioctl+0x6c/0xa0 security/security.c:1568
 __do_sys_ioctl fs/ioctl.c:864 [inline]
 __se_sys_ioctl+0x48/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fdea42afa3b
RSP: 002b:00007ffc9f487360 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fdea42afa3b
RDX: 00007ffc9f487550 RSI: 0000000000008914 RDI: 0000000000000004
RBP: 00007fdea43393c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc9f487551
R13: 00007ffc9f487550 R14: 0000000000000003 R15: 0000000000000001
 </TASK>
rcu: rcu_preempt kthread starved for 10550 jiffies! g7913 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:26912 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 4294 Comm: syz-executor110 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 6e c8 41 f7 48 89 df e8 c6 8d 42 f7 e8 f1 7f 65 f7 fb bf 01 00 00 00 <e8> 16 0b 36 f7 65 8b 05 17 c4 e0 75 85 c0 74 02 5b c3 e8 64 d5 de
RSP: 0018:ffffc90003cd7bb8 EFLAGS: 00000286
RAX: ecd73f5cb6167200 RBX: ffff88801ce81bc0 RCX: ecd73f5cb6167200
RDX: dffffc0000000000 RSI: ffffffff8a8c0500 RDI: 0000000000000001
RBP: ffff88801ce82058 R08: dffffc0000000000 R09: ffffed10039d0379
R10: ffffed10039d0379 R11: 1ffff110039d0378 R12: 1ffff110039d040b
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
FS:  0000555583e023c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000380 CR3: 000000007d592000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x1163/0x1350 kernel/signal.c:2874
 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fdea42afc79
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 91 1a 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc9f4871f8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007fdea42afc79
RDX: 0000200000000500 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 00007fdea426e990 R09: 00007fdea426e990
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fdea430611d
R13: 0000000000000003 R14: 00007ffc9f487230 R15: 0000000000000000
 </TASK>
sched: RT throttling activated

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/10 17:45 linux-6.1.y 882efbdd9d34 ff1712fe .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in security_file_ioctl
2024/02/20 18:27 linux-6.1.y 8b4118fabd6e 3af7dd65 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in security_file_ioctl
2025/05/30 20:20 linux-6.1.y da3c5173c55f 3d2f584d .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in security_file_ioctl
2025/11/16 03:42 linux-6.1.y f6e38ae624cf f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in security_file_ioctl
* Struck through repros no longer work on HEAD.