FAULT_INJECTION: forcing a failure. name fail_usercopy, interval 1, probability 0, space 0, times 0 ====================================================== WARNING: possible circular locking dependency detected 6.14.0-rc6-syzkaller-00103-g4003c9e78778 #0 Not tainted ------------------------------------------------------ syz.5.1213/10614 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: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline] ffff8880b863ec18 (&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 vt_ioctl+0xe51/0x2f80 drivers/tty/vt/vt_ioctl.c:888 tty_ioctl+0x651/0x15d0 drivers/tty/tty_io.c:2802 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 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: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 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7087 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 lock_is_held_type+0x107/0x150 kernel/locking/lockdep.c:5928 lock_is_held include/linux/lockdep.h:249 [inline] __might_resched+0x473/0x5e0 kernel/sched/core.c:8729 __might_fault+0x83/0x190 mm/memory.c:6855 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x29/0xd0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] memdup_user+0x71/0xd0 mm/util.c:222 strndup_user+0x78/0xe0 mm/util.c:277 copy_mount_string fs/namespace.c:3795 [inline] __do_sys_mount fs/namespace.c:4101 [inline] __se_sys_mount fs/namespace.c:4088 [inline] __x64_sys_mount+0x181/0x310 fs/namespace.c:4088 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 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.5.1213/10614: #0: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline] #0: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:591 #1: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #1: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2370 [inline] #1: 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: 10614 Comm: syz.5.1213 Not tainted 6.14.0-rc6-syzkaller-00103-g4003c9e78778 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7087 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_is_held_type+0x107/0x150 kernel/locking/lockdep.c:5928 Code: 00 00 b8 ff ff ff ff 65 0f c1 05 3c 15 ab 74 83 f8 01 75 2d 9c 58 f6 c4 02 75 43 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 <44> 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 45 31 ed eb RSP: 0018:ffffc90003cafd30 EFLAGS: 00000296 RAX: 0000000000000046 RBX: 1ffff92000795faf RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8b6cff80 RDI: ffffffff8bd36ae0 RBP: ffffffff8e1bd0e0 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888061bd4880 R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000000 lock_is_held include/linux/lockdep.h:249 [inline] __might_resched+0x473/0x5e0 kernel/sched/core.c:8729 __might_fault+0x83/0x190 mm/memory.c:6855 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x29/0xd0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] memdup_user+0x71/0xd0 mm/util.c:222 strndup_user+0x78/0xe0 mm/util.c:277 copy_mount_string fs/namespace.c:3795 [inline] __do_sys_mount fs/namespace.c:4101 [inline] __se_sys_mount fs/namespace.c:4088 [inline] __x64_sys_mount+0x181/0x310 fs/namespace.c:4088 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f197978d169 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:00007f197a57d038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f19799a6160 RCX: 00007f197978d169 RDX: 0000400000000080 RSI: 00004000000002c0 RDI: 0000400000000100 RBP: 00007f197a57d090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 00007f19799a6160 R15: 00007ffce50ca988 CPU: 0 UID: 0 PID: 10614 Comm: syz.5.1213 Not tainted 6.14.0-rc6-syzkaller-00103-g4003c9e78778 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7087 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_is_held_type+0x107/0x150 kernel/locking/lockdep.c:5928 Code: 00 00 b8 ff ff ff ff 65 0f c1 05 3c 15 ab 74 83 f8 01 75 2d 9c 58 f6 c4 02 75 43 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 <44> 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 45 31 ed eb RSP: 0018:ffffc90003cafd30 EFLAGS: 00000296 RAX: 0000000000000046 RBX: 1ffff92000795faf RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8b6cff80 RDI: ffffffff8bd36ae0 RBP: ffffffff8e1bd0e0 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888061bd4880 R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000000 lock_is_held include/linux/lockdep.h:249 [inline] __might_resched+0x473/0x5e0 kernel/sched/core.c:8729 __might_fault+0x83/0x190 mm/memory.c:6855 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x29/0xd0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] memdup_user+0x71/0xd0 mm/util.c:222 strndup_user+0x78/0xe0 mm/util.c:277 copy_mount_string fs/namespace.c:3795 [inline] __do_sys_mount fs/namespace.c:4101 [inline] __se_sys_mount fs/namespace.c:4088 [inline] __x64_sys_mount+0x181/0x310 fs/namespace.c:4088 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f197978d169 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:00007f197a57d038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f19799a6160 RCX: 00007f197978d169 RDX: 0000400000000080 RSI: 00004000000002c0 RDI: 0000400000000100 RBP: 00007f197a57d090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 00007f19799a6160 R15: 00007ffce50ca988 ISOFS: Unable to identify CD-ROM format. ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: b8 ff ff ff ff mov $0xffffffff,%eax 7: 65 0f c1 05 3c 15 ab xadd %eax,%gs:0x74ab153c(%rip) # 0x74ab154b e: 74 f: 83 f8 01 cmp $0x1,%eax 12: 75 2d jne 0x41 14: 9c pushf 15: 58 pop %rax 16: f6 c4 02 test $0x2,%ah 19: 75 43 jne 0x5e 1b: 48 f7 04 24 00 02 00 testq $0x200,(%rsp) 22: 00 23: 74 01 je 0x26 25: fb sti 26: 48 83 c4 08 add $0x8,%rsp * 2a: 44 89 e8 mov %r13d,%eax <-- trapping instruction 2d: 5b pop %rbx 2e: 5d pop %rbp 2f: 41 5c pop %r12 31: 41 5d pop %r13 33: 41 5e pop %r14 35: 41 5f pop %r15 37: c3 ret 38: cc int3 39: cc int3 3a: cc int3 3b: cc int3 3c: 45 31 ed xor %r13d,%r13d 3f: eb .byte 0xeb