FAULT_INJECTION: forcing a failure. name fail_usercopy, interval 1, probability 0, space 0, times 0 ====================================================== WARNING: possible circular locking dependency detected 6.1.129-syzkaller #0 Not tainted ------------------------------------------------------ syz.1.2193/10054 is trying to acquire lock: ffffffff8d20a538 ((console_sem).lock){-...}-{2:2}, at: down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:139 but task is already holding lock: ffff8880b8e3a9d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&rq->__lock){-.-.}-{2:2}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 _raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 raw_spin_rq_lock kernel/sched/sched.h:1355 [inline] rq_lock kernel/sched/sched.h:1645 [inline] task_fork_fair+0x5d/0x350 kernel/sched/fair.c:11886 sched_cgroup_fork+0x374/0x400 kernel/sched/core.c:4684 copy_process+0x2482/0x40a0 kernel/fork.c:2383 kernel_clone+0x222/0x920 kernel/fork.c:2681 user_mode_thread+0x140/0x1b0 kernel/fork.c:2757 rest_init+0x23/0x300 init/main.c:698 start_kernel+0x0/0x53f init/main.c:893 start_kernel+0x496/0x53f init/main.c:1140 secondary_startup_64_no_verify+0xcf/0xdb -> #1 (&p->pi_lock){-.-.}-{2:2}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 try_to_wake_up+0xad/0x1250 kernel/sched/core.c:4110 up+0x6e/0x90 kernel/locking/semaphore.c:191 __up_console_sem+0x11a/0x1e0 kernel/printk/printk.c:260 __console_unlock kernel/printk/printk.c:2697 [inline] console_unlock+0x591/0x7c0 kernel/printk/printk.c:2908 vprintk_emit+0x523/0x740 kernel/printk/printk.c:2303 dev_vprintk_emit+0x334/0x3d9 drivers/base/core.c:4932 dev_printk_emit+0xd9/0x118 drivers/base/core.c:4943 _dev_warn+0x11e/0x165 drivers/base/core.c:4999 firmware_fallback_sysfs+0x674/0x940 drivers/base/firmware_loader/fallback.c:229 _request_firmware+0xcf0/0x12b0 drivers/base/firmware_loader/main.c:884 request_firmware_work_func+0x126/0x270 drivers/base/firmware_loader/main.c:1135 process_one_work+0x917/0x1260 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 -> #0 ((console_sem).lock){-...}-{2:2}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:139 __down_trylock_console_sem+0x105/0x250 kernel/printk/printk.c:243 console_trylock kernel/printk/printk.c:2650 [inline] console_trylock_spinning kernel/printk/printk.c:1896 [inline] vprintk_emit+0x1ee/0x740 kernel/printk/printk.c:2302 _printk+0xd1/0x111 kernel/printk/printk.c:2328 fail_dump lib/fault-inject.c:45 [inline] should_fail_ex+0x387/0x4d0 lib/fault-inject.c:147 strncpy_from_user+0x32/0x360 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x6c/0x130 mm/maccess.c:186 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:204 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:213 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:210 bpf_prog_bc7c5c6b9645592f+0x35/0x37 bpf_dispatcher_nop_func include/linux/bpf.h:1000 [inline] __bpf_prog_run include/linux/filter.h:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline] bpf_trace_run4+0x253/0x470 kernel/trace/bpf_trace.c:2325 __traceiter_sched_switch+0x91/0xc0 include/trace/events/sched.h:222 trace_sched_switch include/trace/events/sched.h:222 [inline] __schedule+0x2128/0x4570 kernel/sched/core.c:6557 schedule+0xbf/0x180 kernel/sched/core.c:6636 synchronize_rcu_expedited+0x777/0x930 kernel/rcu/tree_exp.h:977 synchronize_rcu+0x11c/0x3f0 kernel/rcu/tree.c:3576 rcu_sync_enter+0x1f6/0x340 kernel/rcu/sync.c:149 percpu_down_write+0x69/0x2f0 kernel/locking/percpu-rwsem.c:231 cgroup_attach_lock kernel/cgroup/cgroup.c:2455 [inline] cgroup_procs_write_start+0x1b1/0x650 kernel/cgroup/cgroup.c:2959 __cgroup1_procs_write+0xde/0x460 kernel/cgroup/cgroup-v1.c:502 cgroup_file_write+0x2c6/0x6c0 kernel/cgroup/cgroup.c:4077 kernfs_fop_write_iter+0x3a2/0x4f0 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x857/0xbc0 fs/read_write.c:584 ksys_write+0x19c/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 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 *** 9 locks held by syz.1.2193/10054: #0: ffff888029c42868 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ba/0x360 fs/file.c:1032 #1: ffff8880732aa460 (sb_writers#11){.+.+}-{0:0}, at: vfs_write+0x269/0xbc0 fs/read_write.c:580 #2: ffff8880555dbc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:325 #3: ffffffff8d3573e8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:442 [inline] #3: ffffffff8d3573e8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xe5/0x290 kernel/cgroup/cgroup.c:1677 #4: ffffffff8d1cad10 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2453 [inline] #4: ffffffff8d1cad10 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x19c/0x650 kernel/cgroup/cgroup.c:2959 #5: ffffffff8d3575d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2455 [inline] #5: ffffffff8d3575d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x1b1/0x650 kernel/cgroup/cgroup.c:2959 #6: ffffffff8d333cb8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #6: ffffffff8d333cb8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 #7: ffff8880b8e3a9d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #8: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #8: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #8: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2283 [inline] #8: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x16a/0x470 kernel/trace/bpf_trace.c:2325 stack backtrace: CPU: 0 PID: 10054 Comm: syz.1.2193 Not tainted 6.1.129-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:139 __down_trylock_console_sem+0x105/0x250 kernel/printk/printk.c:243 console_trylock kernel/printk/printk.c:2650 [inline] console_trylock_spinning kernel/printk/printk.c:1896 [inline] vprintk_emit+0x1ee/0x740 kernel/printk/printk.c:2302 _printk+0xd1/0x111 kernel/printk/printk.c:2328 fail_dump lib/fault-inject.c:45 [inline] should_fail_ex+0x387/0x4d0 lib/fault-inject.c:147 strncpy_from_user+0x32/0x360 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x6c/0x130 mm/maccess.c:186 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:204 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:213 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:210 bpf_prog_bc7c5c6b9645592f+0x35/0x37 bpf_dispatcher_nop_func include/linux/bpf.h:1000 [inline] __bpf_prog_run include/linux/filter.h:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline] bpf_trace_run4+0x253/0x470 kernel/trace/bpf_trace.c:2325 __traceiter_sched_switch+0x91/0xc0 include/trace/events/sched.h:222 trace_sched_switch include/trace/events/sched.h:222 [inline] __schedule+0x2128/0x4570 kernel/sched/core.c:6557 schedule+0xbf/0x180 kernel/sched/core.c:6636 synchronize_rcu_expedited+0x777/0x930 kernel/rcu/tree_exp.h:977 synchronize_rcu+0x11c/0x3f0 kernel/rcu/tree.c:3576 rcu_sync_enter+0x1f6/0x340 kernel/rcu/sync.c:149 percpu_down_write+0x69/0x2f0 kernel/locking/percpu-rwsem.c:231 cgroup_attach_lock kernel/cgroup/cgroup.c:2455 [inline] cgroup_procs_write_start+0x1b1/0x650 kernel/cgroup/cgroup.c:2959 __cgroup1_procs_write+0xde/0x460 kernel/cgroup/cgroup-v1.c:502 cgroup_file_write+0x2c6/0x6c0 kernel/cgroup/cgroup.c:4077 kernfs_fop_write_iter+0x3a2/0x4f0 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x857/0xbc0 fs/read_write.c:584 ksys_write+0x19c/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f7b9b98d169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7b9c70c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f7b9bba6080 RCX: 00007f7b9b98d169 RDX: 0000000000000012 RSI: 0000400000000380 RDI: 0000000000000005 RBP: 00007f7b9c70c090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 00007f7b9bba6080 R15: 00007ffeb60d71f8 CPU: 0 PID: 10054 Comm: syz.1.2193 Not tainted 6.1.129-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 fail_dump lib/fault-inject.c:52 [inline] should_fail_ex+0x3a6/0x4d0 lib/fault-inject.c:147 strncpy_from_user+0x32/0x360 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x6c/0x130 mm/maccess.c:186 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:204 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:213 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:210 bpf_prog_bc7c5c6b9645592f+0x35/0x37 bpf_dispatcher_nop_func include/linux/bpf.h:1000 [inline] __bpf_prog_run include/linux/filter.h:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline] bpf_trace_run4+0x253/0x470 kernel/trace/bpf_trace.c:2325 __traceiter_sched_switch+0x91/0xc0 include/trace/events/sched.h:222 trace_sched_switch include/trace/events/sched.h:222 [inline] __schedule+0x2128/0x4570 kernel/sched/core.c:6557 schedule+0xbf/0x180 kernel/sched/core.c:6636 synchronize_rcu_expedited+0x777/0x930 kernel/rcu/tree_exp.h:977 synchronize_rcu+0x11c/0x3f0 kernel/rcu/tree.c:3576 rcu_sync_enter+0x1f6/0x340 kernel/rcu/sync.c:149 percpu_down_write+0x69/0x2f0 kernel/locking/percpu-rwsem.c:231 cgroup_attach_lock kernel/cgroup/cgroup.c:2455 [inline] cgroup_procs_write_start+0x1b1/0x650 kernel/cgroup/cgroup.c:2959 __cgroup1_procs_write+0xde/0x460 kernel/cgroup/cgroup-v1.c:502 cgroup_file_write+0x2c6/0x6c0 kernel/cgroup/cgroup.c:4077 kernfs_fop_write_iter+0x3a2/0x4f0 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x857/0xbc0 fs/read_write.c:584 ksys_write+0x19c/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f7b9b98d169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7b9c70c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f7b9bba6080 RCX: 00007f7b9b98d169 RDX: 0000000000000012 RSI: 0000400000000380 RDI: 0000000000000005 RBP: 00007f7b9c70c090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 00007f7b9bba6080 R15: 00007ffeb60d71f8