FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 1
======================================================
WARNING: possible circular locking dependency detected
6.14.0-rc6-syzkaller-00115-ge3a854b577cb #0 Not tainted
------------------------------------------------------
syz.0.405/7449 is trying to acquire lock:
ffffffff8e1aaeb8 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
but task is already holding lock:
ffff88802b43ed58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline]
ffff88802b43ed58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:591
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&rq->__lock){-.-.}-{2:2}:
_raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378
raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:598
raw_spin_rq_lock kernel/sched/sched.h:1521 [inline]
task_rq_lock+0xcf/0x3b0 kernel/sched/core.c:700
cgroup_move_task+0x82/0x250 kernel/sched/psi.c:1161
css_set_move_task+0x288/0x5f0 kernel/cgroup/cgroup.c:898
cgroup_post_fork+0x202/0x9d0 kernel/cgroup/cgroup.c:6695
copy_process+0x4ffd/0x8c50 kernel/fork.c:2629
kernel_clone+0xfd/0x960 kernel/fork.c:2815
user_mode_thread+0xc9/0x110 kernel/fork.c:2893
rest_init+0x23/0x2b0 init/main.c:708
start_kernel+0x3e9/0x4d0 init/main.c:1099
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:515
x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:496
common_startup_64+0x13e/0x148
-> #1 (&p->pi_lock){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline]
try_to_wake_up+0xb6/0x1490 kernel/sched/core.c:4214
up+0x79/0xb0 kernel/locking/semaphore.c:191
__up_console_sem+0x85/0xe0 kernel/printk/printk.c:343
__console_unlock kernel/printk/printk.c:2869 [inline]
__console_flush_and_unlock kernel/printk/printk.c:3271 [inline]
console_unlock+0x1dc/0x210 kernel/printk/printk.c:3309
vga_remove_vgacon drivers/pci/vgaarb.c:186 [inline]
vga_remove_vgacon+0x90/0xd0 drivers/pci/vgaarb.c:167
__aperture_remove_legacy_vga_devices drivers/video/aperture.c:331 [inline]
aperture_remove_conflicting_pci_devices+0x16a/0x1e0 drivers/video/aperture.c:369
bochs_pci_probe+0x29/0xcd0 drivers/gpu/drm/tiny/bochs.c:723
local_pci_probe+0xde/0x1b0 drivers/pci/pci-driver.c:324
pci_call_probe drivers/pci/pci-driver.c:392 [inline]
__pci_device_probe drivers/pci/pci-driver.c:417 [inline]
pci_device_probe+0x673/0x7a0 drivers/pci/pci-driver.c:451
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:658
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:800
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830
__driver_attach+0x283/0x580 drivers/base/dd.c:1216
bus_for_each_dev+0x13c/0x1d0 drivers/base/bus.c:370
bus_add_driver+0x2e9/0x690 drivers/base/bus.c:678
driver_register+0x15c/0x4b0 drivers/base/driver.c:249
drm_pci_register_driver_if_modeset include/drm/drm_module.h:69 [inline]
bochs_pci_driver_init+0x67/0x80 drivers/gpu/drm/tiny/bochs.c:805
do_one_initcall+0x128/0x700 init/main.c:1257
do_initcall_level init/main.c:1319 [inline]
do_initcalls init/main.c:1335 [inline]
do_basic_setup init/main.c:1354 [inline]
kernel_init_freeable+0x5c7/0x900 init/main.c:1568
kernel_init+0x1c/0x2b0 init/main.c:1457
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
-> #0 ((console_sem).lock){-.-.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3163 [inline]
check_prevs_add kernel/locking/lockdep.c:3282 [inline]
validate_chain kernel/locking/lockdep.c:3906 [inline]
__lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228
lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
__down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:326
console_trylock kernel/printk/printk.c:2852 [inline]
console_trylock_spinning kernel/printk/printk.c:2009 [inline]
vprintk_emit+0x3ec/0x6f0 kernel/printk/printk.c:2431
_printk+0xc8/0x100 kernel/printk/printk.c:2457
fail_dump lib/fault-inject.c:66 [inline]
should_fail_ex+0x4df/0x650 lib/fault-inject.c:174
strncpy_from_user+0x3b/0x2d0 lib/strncpy_from_user.c:118
strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:193
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+0xf1/0x170 kernel/trace/bpf_trace.c:306
bpf_prog_c1796171ffc7efef+0x3e/0x40
bpf_dispatcher_nop_func include/linux/bpf.h:1290 [inline]
__bpf_prog_run include/linux/filter.h:701 [inline]
bpf_prog_run include/linux/filter.h:708 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2371 [inline]
bpf_trace_run4+0x245/0x5a0 kernel/trace/bpf_trace.c:2414
__bpf_trace_sched_switch+0x13e/0x190 include/trace/events/sched.h:222
__traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
__do_trace_sched_switch include/trace/events/sched.h:222 [inline]
trace_sched_switch include/trace/events/sched.h:222 [inline]
__schedule+0x160c/0x5890 kernel/sched/core.c:6762
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6857
blk_mq_freeze_queue_wait+0x146/0x190 block/blk-mq.c:200
blk_mq_freeze_queue include/linux/blk-mq.h:920 [inline]
queue_limits_commit_update_frozen+0x93/0x110 block/blk-settings.c:475
nbd_set_size+0x4e8/0x730 drivers/block/nbd.c:374
__nbd_ioctl drivers/block/nbd.c:1593 [inline]
nbd_ioctl+0xcf2/0xd60 drivers/block/nbd.c:1642
compat_blkdev_ioctl+0x2eb/0x7a0 block/ioctl.c:749
__do_compat_sys_ioctl+0x1cb/0x2c0 fs/ioctl.c:1004
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:387
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:412
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
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 ***
6 locks held by syz.0.405/7449:
#0: ffff888024927198 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x151/0xd60 drivers/block/nbd.c:1635
#1: ffff888043a30f98 (&q->limits_lock){+.+.}-{4:4}, at: queue_limits_start_update include/linux/blkdev.h:951 [inline]
#1: ffff888043a30f98 (&q->limits_lock){+.+.}-{4:4}, at: nbd_set_size+0x2c0/0x730 drivers/block/nbd.c:354
#2: ffff888043a309d8 (&q->q_usage_counter(io)#49){+.+.}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 block/blk-mq.c:215
#3: ffff888043a30a10 (&q->q_usage_counter(queue)#33){+.+.}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 block/blk-mq.c:215
#4: ffff88802b43ed58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline]
#4: ffff88802b43ed58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:591
#5: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#5: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#5: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2370 [inline]
#5: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run4+0x1d6/0x5a0 kernel/trace/bpf_trace.c:2414
stack backtrace:
CPU: 0 UID: 0 PID: 7449 Comm: syz.0.405 Not tainted 6.14.0-rc6-syzkaller-00115-ge3a854b577cb #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_circular_bug+0x490/0x760 kernel/locking/lockdep.c:2076
check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2208
check_prev_add kernel/locking/lockdep.c:3163 [inline]
check_prevs_add kernel/locking/lockdep.c:3282 [inline]
validate_chain kernel/locking/lockdep.c:3906 [inline]
__lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228
lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
__down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:326
console_trylock kernel/printk/printk.c:2852 [inline]
console_trylock_spinning kernel/printk/printk.c:2009 [inline]
vprintk_emit+0x3ec/0x6f0 kernel/printk/printk.c:2431
_printk+0xc8/0x100 kernel/printk/printk.c:2457
fail_dump lib/fault-inject.c:66 [inline]
should_fail_ex+0x4df/0x650 lib/fault-inject.c:174
strncpy_from_user+0x3b/0x2d0 lib/strncpy_from_user.c:118
strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:193
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+0xf1/0x170 kernel/trace/bpf_trace.c:306
bpf_prog_c1796171ffc7efef+0x3e/0x40
bpf_dispatcher_nop_func include/linux/bpf.h:1290 [inline]
__bpf_prog_run include/linux/filter.h:701 [inline]
bpf_prog_run include/linux/filter.h:708 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2371 [inline]
bpf_trace_run4+0x245/0x5a0 kernel/trace/bpf_trace.c:2414
__bpf_trace_sched_switch+0x13e/0x190 include/trace/events/sched.h:222
__traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
__do_trace_sched_switch include/trace/events/sched.h:222 [inline]
trace_sched_switch include/trace/events/sched.h:222 [inline]
__schedule+0x160c/0x5890 kernel/sched/core.c:6762
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6857
blk_mq_freeze_queue_wait+0x146/0x190 block/blk-mq.c:200
blk_mq_freeze_queue include/linux/blk-mq.h:920 [inline]
queue_limits_commit_update_frozen+0x93/0x110 block/blk-settings.c:475
nbd_set_size+0x4e8/0x730 drivers/block/nbd.c:374
__nbd_ioctl drivers/block/nbd.c:1593 [inline]
nbd_ioctl+0xcf2/0xd60 drivers/block/nbd.c:1642
compat_blkdev_ioctl+0x2eb/0x7a0 block/ioctl.c:749
__do_compat_sys_ioctl+0x1cb/0x2c0 fs/ioctl.c:1004
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:387
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:412
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f54579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f503455c EFLAGS: 00000296 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000000ab07
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
CPU: 0 UID: 0 PID: 7449 Comm: syz.0.405 Not tainted 6.14.0-rc6-syzkaller-00115-ge3a854b577cb #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
fail_dump lib/fault-inject.c:73 [inline]
should_fail_ex+0x50a/0x650 lib/fault-inject.c:174
strncpy_from_user+0x3b/0x2d0 lib/strncpy_from_user.c:118
strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:193
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+0xf1/0x170 kernel/trace/bpf_trace.c:306
bpf_prog_c1796171ffc7efef+0x3e/0x40
bpf_dispatcher_nop_func include/linux/bpf.h:1290 [inline]
__bpf_prog_run include/linux/filter.h:701 [inline]
bpf_prog_run include/linux/filter.h:708 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2371 [inline]
bpf_trace_run4+0x245/0x5a0 kernel/trace/bpf_trace.c:2414
__bpf_trace_sched_switch+0x13e/0x190 include/trace/events/sched.h:222
__traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
__do_trace_sched_switch include/trace/events/sched.h:222 [inline]
trace_sched_switch include/trace/events/sched.h:222 [inline]
__schedule+0x160c/0x5890 kernel/sched/core.c:6762
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6857
blk_mq_freeze_queue_wait+0x146/0x190 block/blk-mq.c:200
blk_mq_freeze_queue include/linux/blk-mq.h:920 [inline]
queue_limits_commit_update_frozen+0x93/0x110 block/blk-settings.c:475
nbd_set_size+0x4e8/0x730 drivers/block/nbd.c:374
__nbd_ioctl drivers/block/nbd.c:1593 [inline]
nbd_ioctl+0xcf2/0xd60 drivers/block/nbd.c:1642
compat_blkdev_ioctl+0x2eb/0x7a0 block/ioctl.c:749
__do_compat_sys_ioctl+0x1cb/0x2c0 fs/ioctl.c:1004
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:387
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:412
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f54579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f503455c EFLAGS: 00000296 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000000ab07
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
nbd0: detected capacity change from 4294967294 to 0
----------------
Code disassembly (best guess), 2 bytes skipped:
0: 10 06 adc %al,(%rsi)
2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi
6: 10 07 adc %al,(%rdi)
8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi
c: 10 08 adc %cl,(%rax)
e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi
1e: 00 51 52 add %dl,0x52(%rcx)
21: 55 push %rbp
22: 89 e5 mov %esp,%ebp
24: 0f 34 sysenter
26: cd 80 int $0x80
* 28: 5d pop %rbp <-- trapping instruction
29: 5a pop %rdx
2a: 59 pop %rcx
2b: c3 ret
2c: 90 nop
2d: 90 nop
2e: 90 nop
2f: 90 nop
30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi
37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi