FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 0
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.3.13285/15515 is trying to acquire lock:
ffffffff8e12e100 (console_owner){-...}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:336 [inline]
ffffffff8e12e100 (console_owner){-...}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:319 [inline]
ffffffff8e12e100 (console_owner){-...}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:288 [inline]
ffffffff8e12e100 (console_owner){-...}-{0:0}, at: console_flush_all+0x13a/0xc40 kernel/printk/printk.c:3203
but task is already holding lock:
ffff8880b8739f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:636
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #4 (&rq->__lock){-.-.}-{2:2}:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
_raw_spin_lock_nested+0x32/0x50 kernel/locking/spinlock.c:378
raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:636
raw_spin_rq_lock kernel/sched/sched.h:1519 [inline]
task_rq_lock+0xbc/0x470 kernel/sched/core.c:736
cgroup_move_task+0x92/0x2a0 kernel/sched/psi.c:1170
css_set_move_task+0x658/0x9e0 kernel/cgroup/cgroup.c:918
cgroup_post_fork+0x1ef/0x790 kernel/cgroup/cgroup.c:6759
copy_process+0x3862/0x3c00 kernel/fork.c:2419
kernel_clone+0x21e/0x840 kernel/fork.c:2605
user_mode_thread+0xdd/0x140 kernel/fork.c:2683
rest_init+0x23/0x300 init/main.c:709
start_kernel+0x3a9/0x410 init/main.c:1097
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288
common_startup_64+0x13e/0x147
-> #3 (&p->pi_lock){-.-.}-{2:2}:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline]
try_to_wake_up+0x67/0x12b0 kernel/sched/core.c:4216
__wake_up_common kernel/sched/wait.c:108 [inline]
__wake_up_common_lock+0x137/0x1f0 kernel/sched/wait.c:125
tty_port_default_wakeup+0xa2/0xf0 drivers/tty/tty_port.c:69
serial8250_tx_chars+0x72e/0x970 drivers/tty/serial/8250/8250_port.c:1728
serial8250_handle_irq+0x633/0xbb0 drivers/tty/serial/8250/8250_port.c:1836
serial8250_default_handle_irq+0xbf/0x1e0 drivers/tty/serial/8250/8250_port.c:1856
serial8250_interrupt+0x8a/0x160 drivers/tty/serial/8250/8250_core.c:82
__handle_irq_event_percpu+0x289/0x980 kernel/irq/handle.c:158
handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:210
handle_edge_irq+0x23b/0xa10 kernel/irq/chip.c:855
generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
handle_irq arch/x86/kernel/irq.c:254 [inline]
call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
__common_interrupt+0x141/0x1f0 arch/x86/kernel/irq.c:325
common_interrupt+0xb6/0xe0 arch/x86/kernel/irq.c:318
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:81
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e8/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
rest_init+0x2de/0x300 init/main.c:744
start_kernel+0x3a9/0x410 init/main.c:1097
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288
common_startup_64+0x13e/0x147
-> #2 (&tty->write_wait){-...}-{3:3}:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
__wake_up_common_lock+0x2f/0x1f0 kernel/sched/wait.c:124
tty_port_default_wakeup+0xa2/0xf0 drivers/tty/tty_port.c:69
serial8250_tx_chars+0x72e/0x970 drivers/tty/serial/8250/8250_port.c:1728
serial8250_handle_irq+0x633/0xbb0 drivers/tty/serial/8250/8250_port.c:1836
serial8250_default_handle_irq+0xbf/0x1e0 drivers/tty/serial/8250/8250_port.c:1856
serial8250_interrupt+0x8a/0x160 drivers/tty/serial/8250/8250_core.c:82
__handle_irq_event_percpu+0x289/0x980 kernel/irq/handle.c:158
handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:210
handle_edge_irq+0x23b/0xa10 kernel/irq/chip.c:855
generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
handle_irq arch/x86/kernel/irq.c:254 [inline]
call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
__common_interrupt+0x141/0x1f0 arch/x86/kernel/irq.c:325
common_interrupt+0xb6/0xe0 arch/x86/kernel/irq.c:318
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:81
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e8/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
rest_init+0x2de/0x300 init/main.c:744
start_kernel+0x3a9/0x410 init/main.c:1097
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288
common_startup_64+0x13e/0x147
-> #1 (&port_lock_key){-...}-{3:3}:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
uart_port_lock_irqsave include/linux/serial_core.h:717 [inline]
serial8250_console_write+0x17e/0x1ba0 drivers/tty/serial/8250/8250_port.c:3355
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x728/0xc40 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
_printk+0xcf/0x120 kernel/printk/printk.c:2475
register_console+0xa8b/0xf90 kernel/printk/printk.c:4126
univ8250_console_init+0x3a/0x70 drivers/tty/serial/8250/8250_core.c:516
console_init+0x10e/0x430 kernel/printk/printk.c:4325
start_kernel+0x254/0x410 init/main.c:1035
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288
common_startup_64+0x13e/0x147
-> #0 (console_owner){-...}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908
__lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
console_lock_spinning_enable kernel/printk/printk.c:1924 [inline]
console_emit_next_record kernel/printk/printk.c:3132 [inline]
console_flush_all+0x6d2/0xc40 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
_printk+0xcf/0x120 kernel/printk/printk.c:2475
fail_dump lib/fault-inject.c:66 [inline]
should_fail_ex+0x3f5/0x560 lib/fault-inject.c:174
strncpy_from_user+0x36/0x290 lib/strncpy_from_user.c:118
strncpy_from_user_nofault+0x72/0x150 mm/maccess.c:192
bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:215 [inline]
____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:310 [inline]
bpf_probe_read_compat_str+0xe2/0x180 kernel/trace/bpf_trace.c:306
bpf_prog_5646b9e3b5361e32+0x75/0x7d
bpf_dispatcher_nop_func include/linux/bpf.h:1335 [inline]
__bpf_prog_run include/linux/filter.h:718 [inline]
bpf_prog_run include/linux/filter.h:725 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline]
bpf_trace_run2+0x281/0x4b0 kernel/trace/bpf_trace.c:2298
__bpf_trace_tlb_flush+0xf5/0x150 include/trace/events/tlb.h:38
__do_trace_tlb_flush include/trace/events/tlb.h:38 [inline]
trace_tlb_flush+0x115/0x140 include/trace/events/tlb.h:38
switch_mm_irqs_off+0x53e/0x7a0 arch/x86/mm/tlb.c:-1
context_switch kernel/sched/core.c:5341 [inline]
__schedule+0x110e/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7145
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7169
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__local_bh_enable_ip+0x13e/0x1c0 kernel/softirq.c:414
local_bh_enable include/linux/bottom_half.h:33 [inline]
bpf_test_run+0x376/0x7b0 net/bpf/test_run.c:437
bpf_prog_test_run_skb+0xb30/0x1560 net/bpf/test_run.c:1099
bpf_prog_test_run+0x2c4/0x340 kernel/bpf/syscall.c:4590
__sys_bpf+0x581/0x870 kernel/bpf/syscall.c:6047
__do_sys_bpf kernel/bpf/syscall.c:6139 [inline]
__se_sys_bpf kernel/bpf/syscall.c:6137 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6137
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
other info that might help us debug this:
Chain exists of:
console_owner --> &p->pi_lock --> &rq->__lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&rq->__lock);
lock(&p->pi_lock);
lock(&rq->__lock);
lock(console_owner);
*** DEADLOCK ***
5 locks held by syz.3.13285/15515:
#0: ffffffff8e139ea0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e139ea0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e139ea0 (rcu_read_lock){....}-{1:3}, at: bpf_test_timer_enter+0x1a/0x140 net/bpf/test_run.c:40
#1: ffff8880b8739f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:636
#2: ffffffff8e139ea0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#2: ffffffff8e139ea0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#2: ffffffff8e139ea0 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2256 [inline]
#2: ffffffff8e139ea0 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run2+0x186/0x4b0 kernel/trace/bpf_trace.c:2298
#3: ffffffff8e12e160 (console_lock){+.+.}-{0:0}, at: _printk+0xcf/0x120 kernel/printk/printk.c:2475
#4: ffffffff8e015a30 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:336 [inline]
#4: ffffffff8e015a30 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:319 [inline]
#4: ffffffff8e015a30 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:288 [inline]
#4: ffffffff8e015a30 (console_srcu){....}-{0:0}, at: console_flush_all+0x13a/0xc40 kernel/printk/printk.c:3203
stack backtrace:
CPU: 1 UID: 0 PID: 15515 Comm: syz.3.13285 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2043
check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2175
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908
__lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
console_lock_spinning_enable kernel/printk/printk.c:1924 [inline]
console_emit_next_record kernel/printk/printk.c:3132 [inline]
console_flush_all+0x6d2/0xc40 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
_printk+0xcf/0x120 kernel/printk/printk.c:2475
fail_dump lib/fault-inject.c:66 [inline]
should_fail_ex+0x3f5/0x560 lib/fault-inject.c:174
strncpy_from_user+0x36/0x290 lib/strncpy_from_user.c:118
strncpy_from_user_nofault+0x72/0x150 mm/maccess.c:192
bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:215 [inline]
____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:310 [inline]
bpf_probe_read_compat_str+0xe2/0x180 kernel/trace/bpf_trace.c:306
bpf_prog_5646b9e3b5361e32+0x75/0x7d
bpf_dispatcher_nop_func include/linux/bpf.h:1335 [inline]
__bpf_prog_run include/linux/filter.h:718 [inline]
bpf_prog_run include/linux/filter.h:725 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline]
bpf_trace_run2+0x281/0x4b0 kernel/trace/bpf_trace.c:2298
__bpf_trace_tlb_flush+0xf5/0x150 include/trace/events/tlb.h:38
__do_trace_tlb_flush include/trace/events/tlb.h:38 [inline]
trace_tlb_flush+0x115/0x140 include/trace/events/tlb.h:38
switch_mm_irqs_off+0x53e/0x7a0 arch/x86/mm/tlb.c:-1
context_switch kernel/sched/core.c:5341 [inline]
__schedule+0x110e/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7145
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7169
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__local_bh_enable_ip+0x13e/0x1c0 kernel/softirq.c:414
local_bh_enable include/linux/bottom_half.h:33 [inline]
bpf_test_run+0x376/0x7b0 net/bpf/test_run.c:437
bpf_prog_test_run_skb+0xb30/0x1560 net/bpf/test_run.c:1099
bpf_prog_test_run+0x2c4/0x340 kernel/bpf/syscall.c:4590
__sys_bpf+0x581/0x870 kernel/bpf/syscall.c:6047
__do_sys_bpf kernel/bpf/syscall.c:6139 [inline]
__se_sys_bpf kernel/bpf/syscall.c:6137 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6137
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc18a98ebe9
Code: Unable to access opcode bytes at 0x7fc18a98ebbf.
RSP: 002b:00007fc18b8b1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fc18abb5fa0 RCX: 00007fc18a98ebe9
RDX: 0000000000000048 RSI: 00002000000002c0 RDI: 000000000000000a
RBP: 00007fc18b8b1090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fc18abb6038 R14: 00007fc18abb5fa0 R15: 00007ffc4ab9df78
CPU: 1 UID: 0 PID: 15515 Comm: syz.3.13285 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
fail_dump lib/fault-inject.c:73 [inline]
should_fail_ex+0x414/0x560 lib/fault-inject.c:174
strncpy_from_user+0x36/0x290 lib/strncpy_from_user.c:118
strncpy_from_user_nofault+0x72/0x150 mm/maccess.c:192
bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:215 [inline]
____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:310 [inline]
bpf_probe_read_compat_str+0xe2/0x180 kernel/trace/bpf_trace.c:306
bpf_prog_5646b9e3b5361e32+0x75/0x7d
bpf_dispatcher_nop_func include/linux/bpf.h:1335 [inline]
__bpf_prog_run include/linux/filter.h:718 [inline]
bpf_prog_run include/linux/filter.h:725 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline]
bpf_trace_run2+0x281/0x4b0 kernel/trace/bpf_trace.c:2298
__bpf_trace_tlb_flush+0xf5/0x150 include/trace/events/tlb.h:38
__do_trace_tlb_flush include/trace/events/tlb.h:38 [inline]
trace_tlb_flush+0x115/0x140 include/trace/events/tlb.h:38
switch_mm_irqs_off+0x53e/0x7a0 arch/x86/mm/tlb.c:-1
context_switch kernel/sched/core.c:5341 [inline]
__schedule+0x110e/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7145
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7169
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__local_bh_enable_ip+0x13e/0x1c0 kernel/softirq.c:414
local_bh_enable include/linux/bottom_half.h:33 [inline]
bpf_test_run+0x376/0x7b0 net/bpf/test_run.c:437
bpf_prog_test_run_skb+0xb30/0x1560 net/bpf/test_run.c:1099
bpf_prog_test_run+0x2c4/0x340 kernel/bpf/syscall.c:4590
__sys_bpf+0x581/0x870 kernel/bpf/syscall.c:6047
__do_sys_bpf kernel/bpf/syscall.c:6139 [inline]
__se_sys_bpf kernel/bpf/syscall.c:6137 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6137
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc18a98ebe9
Code: Unable to access opcode bytes at 0x7fc18a98ebbf.
RSP: 002b:00007fc18b8b1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fc18abb5fa0 RCX: 00007fc18a98ebe9
RDX: 0000000000000048 RSI: 00002000000002c0 RDI: 000000000000000a
RBP: 00007fc18b8b1090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fc18abb6038 R14: 00007fc18abb5fa0 R15: 00007ffc4ab9df78