FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 0
======================================================
WARNING: possible circular locking dependency detected
6.11.0-rc6-syzkaller-00048-gc7fb1692dc01 #0 Not tainted
------------------------------------------------------
syz.3.91/5609 is trying to acquire lock:
ffffffff8e613cb8 ((console_sem).lock){-...}-{2:2}, at: down_trylock+0x20/0xa0 kernel/locking/semaphore.c:139

but task is already holding lock:
ffff8880b893e998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:560

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&rq->__lock){-.-.}-{2:2}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378
       raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:560
       raw_spin_rq_lock kernel/sched/sched.h:1415 [inline]
       rq_lock kernel/sched/sched.h:1714 [inline]
       task_fork_fair+0x61/0x1e0 kernel/sched/fair.c:12710
       sched_cgroup_fork+0x37c/0x410 kernel/sched/core.c:4633
       copy_process+0x2217/0x3dc0 kernel/fork.c:2483
       kernel_clone+0x223/0x880 kernel/fork.c:2781
       user_mode_thread+0x132/0x1a0 kernel/fork.c:2859
       rest_init+0x23/0x300 init/main.c:712
       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

-> #1 (&p->pi_lock){-.-.}-{2:2}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
       class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline]
       try_to_wake_up+0xb0/0x1470 kernel/sched/core.c:4051
       up+0x72/0x90 kernel/locking/semaphore.c:191
       __up_console_sem kernel/printk/printk.c:340 [inline]
       __console_unlock kernel/printk/printk.c:2801 [inline]
       console_unlock+0x20d/0x4d0 kernel/printk/printk.c:3120
       vprintk_emit+0x5dc/0x7c0 kernel/printk/printk.c:2348
       _printk+0xd5/0x120 kernel/printk/printk.c:2373
       printk_stack_address arch/x86/kernel/dumpstack.c:72 [inline]
       show_trace_log_lvl+0x43a/0x520 arch/x86/kernel/dumpstack.c:285
       __dump_stack lib/dump_stack.c:93 [inline]
       dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
       fail_dump lib/fault-inject.c:52 [inline]
       should_fail_ex+0x3b0/0x4e0 lib/fault-inject.c:153
       should_failslab+0xac/0x100 mm/failslab.c:45
       slab_pre_alloc_hook mm/slub.c:3945 [inline]
       slab_alloc_node mm/slub.c:4021 [inline]
       __do_kmalloc_node mm/slub.c:4161 [inline]
       __kmalloc_noprof+0xd8/0x400 mm/slub.c:4174
       kmalloc_noprof include/linux/slab.h:685 [inline]
       tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251
       tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
       tomoyo_path_number_perm+0x23a/0x880 security/tomoyo/file.c:723
       security_file_ioctl+0x75/0xb0 security/security.c:2791
       __do_sys_ioctl fs/ioctl.c:901 [inline]
       __se_sys_ioctl+0x47/0x170 fs/ioctl.c:893
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 ((console_sem).lock){-...}-{2:2}:
       check_prev_add kernel/locking/lockdep.c:3133 [inline]
       check_prevs_add kernel/locking/lockdep.c:3252 [inline]
       validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
       __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
       down_trylock+0x20/0xa0 kernel/locking/semaphore.c:139
       __down_trylock_console_sem+0x109/0x250 kernel/printk/printk.c:323
       console_trylock kernel/printk/printk.c:2754 [inline]
       console_trylock_spinning kernel/printk/printk.c:1958 [inline]
       vprintk_emit+0x2aa/0x7c0 kernel/printk/printk.c:2347
       _printk+0xd5/0x120 kernel/printk/printk.c:2373
       fail_dump lib/fault-inject.c:45 [inline]
       should_fail_ex+0x391/0x4e0 lib/fault-inject.c:153
       strncpy_from_user+0x36/0x2e0 lib/strncpy_from_user.c:118
       strncpy_from_user_nofault+0x71/0x140 mm/maccess.c:186
       bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
       ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:225 [inline]
       bpf_probe_read_user_str+0x2a/0x70 kernel/trace/bpf_trace.c:222
       bpf_prog_b1bc9f7c1f89903c+0x40/0x42
       bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
       __bpf_prog_run include/linux/filter.h:691 [inline]
       bpf_prog_run include/linux/filter.h:698 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
       bpf_trace_run4+0x334/0x590 kernel/trace/bpf_trace.c:2449
       trace_sched_switch include/trace/events/sched.h:222 [inline]
       __schedule+0x253f/0x4a10 kernel/sched/core.c:6526
       __schedule_loop kernel/sched/core.c:6606 [inline]
       schedule+0x14b/0x320 kernel/sched/core.c:6621
       exit_to_user_mode_loop kernel/entry/common.c:102 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
       __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
       syscall_exit_to_user_mode+0x13e/0x370 kernel/entry/common.c:218
       do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  (console_sem).lock --> &p->pi_lock --> &rq->__lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&rq->__lock);
                               lock(&p->pi_lock);
                               lock(&rq->__lock);
  lock((console_sem).lock);

 *** DEADLOCK ***

2 locks held by syz.3.91/5609:
 #0: ffff8880b893e998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:560
 #1: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
 #1: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #1: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2405 [inline]
 #1: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x244/0x590 kernel/trace/bpf_trace.c:2449

stack backtrace:
CPU: 1 UID: 0 PID: 5609 Comm: syz.3.91 Not tainted 6.11.0-rc6-syzkaller-00048-gc7fb1692dc01 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2186
 check_prev_add kernel/locking/lockdep.c:3133 [inline]
 check_prevs_add kernel/locking/lockdep.c:3252 [inline]
 validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
 down_trylock+0x20/0xa0 kernel/locking/semaphore.c:139
 __down_trylock_console_sem+0x109/0x250 kernel/printk/printk.c:323
 console_trylock kernel/printk/printk.c:2754 [inline]
 console_trylock_spinning kernel/printk/printk.c:1958 [inline]
 vprintk_emit+0x2aa/0x7c0 kernel/printk/printk.c:2347
 _printk+0xd5/0x120 kernel/printk/printk.c:2373
 fail_dump lib/fault-inject.c:45 [inline]
 should_fail_ex+0x391/0x4e0 lib/fault-inject.c:153
 strncpy_from_user+0x36/0x2e0 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x71/0x140 mm/maccess.c:186
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
 ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:225 [inline]
 bpf_probe_read_user_str+0x2a/0x70 kernel/trace/bpf_trace.c:222
 bpf_prog_b1bc9f7c1f89903c+0x40/0x42
 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
 __bpf_prog_run include/linux/filter.h:691 [inline]
 bpf_prog_run include/linux/filter.h:698 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
 bpf_trace_run4+0x334/0x590 kernel/trace/bpf_trace.c:2449
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x253f/0x4a10 kernel/sched/core.c:6526
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 exit_to_user_mode_loop kernel/entry/common.c:102 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x13e/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff6e2d7b9df
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 c9 8d 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 1c 8e 02 00 48
RSP: 002b:00007ff6e3bc3030 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: 0000000000000001 RBX: 000000000000000a RCX: 00007ff6e2d7b9df
RDX: 0000000000000001 RSI: 00007ff6e3bc3090 RDI: 000000000000000a
RBP: 00007ff6e3bc3090 R08: 0000000000000000 R09: 00007ff6e3bc2df7
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 0000000000000000 R14: 00007ff6e2f36130 R15: 00007ffe18b8dfb8
 </TASK>
CPU: 1 UID: 0 PID: 5609 Comm: syz.3.91 Not tainted 6.11.0-rc6-syzkaller-00048-gc7fb1692dc01 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail_ex+0x3b0/0x4e0 lib/fault-inject.c:153
 strncpy_from_user+0x36/0x2e0 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x71/0x140 mm/maccess.c:186
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
 ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:225 [inline]
 bpf_probe_read_user_str+0x2a/0x70 kernel/trace/bpf_trace.c:222
 bpf_prog_b1bc9f7c1f89903c+0x40/0x42
 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
 __bpf_prog_run include/linux/filter.h:691 [inline]
 bpf_prog_run include/linux/filter.h:698 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
 bpf_trace_run4+0x334/0x590 kernel/trace/bpf_trace.c:2449
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x253f/0x4a10 kernel/sched/core.c:6526
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 exit_to_user_mode_loop kernel/entry/common.c:102 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x13e/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff6e2d7b9df
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 c9 8d 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 1c 8e 02 00 48
RSP: 002b:00007ff6e3bc3030 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: 0000000000000001 RBX: 000000000000000a RCX: 00007ff6e2d7b9df
RDX: 0000000000000001 RSI: 00007ff6e3bc3090 RDI: 000000000000000a
RBP: 00007ff6e3bc3090 R08: 0000000000000000 R09: 00007ff6e3bc2df7
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 0000000000000000 R14: 00007ff6e2f36130 R15: 00007ffe18b8dfb8
 </TASK>