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-rc7-syzkaller-00133-ge936e7d4a83b #0 Not tainted
------------------------------------------------------
syz.2.638/7518 is trying to acquire lock:
ffffffff8dda75d8 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
but task is already holding lock:
ffff88802b63edd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:568 [inline]
ffff88802b63edd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:553
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:560
raw_spin_rq_lock kernel/sched/sched.h:1415 [inline]
rq_lock kernel/sched/sched.h:1714 [inline]
task_fork_fair+0x73/0x250 kernel/sched/fair.c:12710
sched_cgroup_fork+0x3cf/0x510 kernel/sched/core.c:4633
copy_process+0x4710/0x6f50 kernel/fork.c:2483
kernel_clone+0xfd/0x960 kernel/fork.c:2781
user_mode_thread+0xb4/0xf0 kernel/fork.c:2859
rest_init+0x23/0x2b0 init/main.c:712
start_kernel+0x3df/0x4c0 init/main.c:1103
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507
x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488
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+0x9a/0x13e0 kernel/sched/core.c:4051
up+0x79/0xb0 kernel/locking/semaphore.c:191
__up_console_sem kernel/printk/printk.c:340 [inline]
__console_unlock kernel/printk/printk.c:2802 [inline]
console_unlock+0x23e/0x290 kernel/printk/printk.c:3121
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+0x101/0x1150 drivers/gpu/drm/tiny/bochs.c:648
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+0x29d/0x7b0 drivers/pci/pci-driver.c:451
call_driver_probe drivers/base/dd.c:578 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:657
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
__driver_attach+0x283/0x580 drivers/base/dd.c:1215
bus_for_each_dev+0x13c/0x1d0 drivers/base/bus.c:368
bus_add_driver+0x2e9/0x690 drivers/base/bus.c:673
driver_register+0x15c/0x4b0 drivers/base/driver.c:246
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:732
do_one_initcall+0x128/0x630 init/main.c:1267
do_initcall_level init/main.c:1329 [inline]
do_initcalls init/main.c:1345 [inline]
do_basic_setup init/main.c:1364 [inline]
kernel_init_freeable+0x660/0xc50 init/main.c:1578
kernel_init+0x1c/0x2b0 init/main.c:1467
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
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:3133 [inline]
check_prevs_add kernel/locking/lockdep.c:3252 [inline]
validate_chain kernel/locking/lockdep.c:3868 [inline]
__lock_acquire+0x24ed/0x3cb0 kernel/locking/lockdep.c:5142
lock_acquire kernel/locking/lockdep.c:5759 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724
__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:323
console_trylock kernel/printk/printk.c:2755 [inline]
console_trylock_spinning kernel/printk/printk.c:1958 [inline]
vprintk_emit+0x3d3/0x600 kernel/printk/printk.c:2347
vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:45
_printk+0xc8/0x100 kernel/printk/printk.c:2373
fail_dump lib/fault-inject.c:45 [inline]
should_fail_ex+0x46c/0x5b0 lib/fault-inject.c:153
strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
strncpy_from_user_nofault+0x7f/0x180 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+0x26/0x70 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+0x245/0x5a0 kernel/trace/bpf_trace.c:2449
__traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
trace_sched_switch include/trace/events/sched.h:222 [inline]
__schedule+0x17cf/0x5490 kernel/sched/core.c:6526
__schedule_loop kernel/sched/core.c:6606 [inline]
schedule+0xe7/0x350 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+0xf5/0x2a0 kernel/entry/common.c:218
__do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
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 ***
2 locks held by syz.2.638/7518:
#0: ffff88802b63edd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:568 [inline]
#0: ffff88802b63edd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:553
#1: ffffffff8ddb94a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
#1: ffffffff8ddb94a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#1: ffffffff8ddb94a0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2405 [inline]
#1: ffffffff8ddb94a0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x1d6/0x5a0 kernel/trace/bpf_trace.c:2449
stack backtrace:
CPU: 1 UID: 0 PID: 7518 Comm: syz.2.638 Not tainted 6.11.0-rc7-syzkaller-00133-ge936e7d4a83b #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:93 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
check_noncircular+0x31a/0x400 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 kernel/locking/lockdep.c:3868 [inline]
__lock_acquire+0x24ed/0x3cb0 kernel/locking/lockdep.c:5142
lock_acquire kernel/locking/lockdep.c:5759 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724
__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:323
console_trylock kernel/printk/printk.c:2755 [inline]
console_trylock_spinning kernel/printk/printk.c:1958 [inline]
vprintk_emit+0x3d3/0x600 kernel/printk/printk.c:2347
vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:45
_printk+0xc8/0x100 kernel/printk/printk.c:2373
fail_dump lib/fault-inject.c:45 [inline]
should_fail_ex+0x46c/0x5b0 lib/fault-inject.c:153
strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
strncpy_from_user_nofault+0x7f/0x180 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+0x26/0x70 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+0x245/0x5a0 kernel/trace/bpf_trace.c:2449
__traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
trace_sched_switch include/trace/events/sched.h:222 [inline]
__schedule+0x17cf/0x5490 kernel/sched/core.c:6526
__schedule_loop kernel/sched/core.c:6606 [inline]
schedule+0xe7/0x350 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+0xf5/0x2a0 kernel/entry/common.c:218
__do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f11579
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:00000000f56965a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000004
RAX: 0000000000000001 RBX: 0000000000000005 RCX: 00000000f5696610
RDX: 0000000000000001 RSI: 00000000f739bff4 RDI: 0000000000000000
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
CPU: 1 UID: 0 PID: 7518 Comm: syz.2.638 Not tainted 6.11.0-rc7-syzkaller-00133-ge936e7d4a83b #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:93 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
fail_dump lib/fault-inject.c:52 [inline]
should_fail_ex+0x497/0x5b0 lib/fault-inject.c:153
strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
strncpy_from_user_nofault+0x7f/0x180 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+0x26/0x70 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+0x245/0x5a0 kernel/trace/bpf_trace.c:2449
__traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
trace_sched_switch include/trace/events/sched.h:222 [inline]
__schedule+0x17cf/0x5490 kernel/sched/core.c:6526
__schedule_loop kernel/sched/core.c:6606 [inline]
schedule+0xe7/0x350 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+0xf5/0x2a0 kernel/entry/common.c:218
__do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f11579
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:00000000f56965a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000004
RAX: 0000000000000001 RBX: 0000000000000005 RCX: 00000000f5696610
RDX: 0000000000000001 RSI: 00000000f739bff4 RDI: 0000000000000000
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
----------------
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