[U] 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.4.4004/21781 is trying to acquire lock: ffffffff8e2d1540 (console_owner){-.-.}-{0:0}, at: console_trylock_spinning kernel/printk/printk.c:2021 [inline] ffffffff8e2d1540 (console_owner){-.-.}-{0:0}, at: vprintk_emit+0x493/0x680 kernel/printk/printk.c:2422 but task is already holding lock: ffff88802b23a4d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:646 [inline] ffff88802b23a4d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:631 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&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:638 raw_spin_rq_lock kernel/sched/sched.h:1546 [inline] task_rq_lock+0xcf/0x490 kernel/sched/core.c:738 cgroup_move_task+0x81/0x2a0 kernel/sched/psi.c:1170 css_set_move_task+0x288/0x5f0 kernel/cgroup/cgroup.c:951 cgroup_post_fork+0x201/0x9d0 kernel/cgroup/cgroup.c:6913 copy_process+0x602d/0x76a0 kernel/fork.c:2425 kernel_clone+0xfc/0x930 kernel/fork.c:2609 user_mode_thread+0xc8/0x110 kernel/fork.c:2685 rest_init+0x23/0x2b0 init/main.c:722 start_kernel+0x3f3/0x4e0 init/main.c:1111 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x148 -> #3 (&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:557 [inline] try_to_wake_up+0xb7/0x1870 kernel/sched/core.c:4181 __wake_up_common+0x135/0x1f0 kernel/sched/wait.c:108 __wake_up_common_lock kernel/sched/wait.c:125 [inline] __wake_up+0x31/0x60 kernel/sched/wait.c:146 tty_port_default_wakeup+0x47/0x60 drivers/tty/tty_port.c:67 serial8250_tx_chars+0x68e/0x860 drivers/tty/serial/8250/8250_port.c:1719 serial8250_handle_irq+0x761/0xcb0 drivers/tty/serial/8250/8250_port.c:1827 serial8250_default_handle_irq+0x9e/0x270 drivers/tty/serial/8250/8250_port.c:1846 serial8250_interrupt+0xf5/0x1d0 drivers/tty/serial/8250/8250_core.c:82 __handle_irq_event_percpu+0x236/0x920 kernel/irq/handle.c:203 handle_irq_event_percpu kernel/irq/handle.c:240 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:257 handle_edge_irq+0x3ca/0x9e0 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:310 [inline] __common_interrupt+0xcd/0x2f0 arch/x86/kernel/irq.c:325 common_interrupt+0xba/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+0xf/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:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x38d/0x500 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148 -> #2 (&tty->write_wait){-...}-{3:3}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 __wake_up_common_lock kernel/sched/wait.c:124 [inline] __wake_up+0x1c/0x60 kernel/sched/wait.c:146 tty_port_default_wakeup+0x47/0x60 drivers/tty/tty_port.c:67 serial8250_tx_chars+0x68e/0x860 drivers/tty/serial/8250/8250_port.c:1719 __start_tx+0x3df/0x490 drivers/tty/serial/8250/8250_port.c:1426 serial8250_start_tx+0x368/0x530 drivers/tty/serial/8250/8250_port.c:1535 __uart_start+0x295/0x500 drivers/tty/serial/serial_core.c:161 uart_write+0x218/0xb30 drivers/tty/serial/serial_core.c:633 process_output_block drivers/tty/n_tty.c:561 [inline] n_tty_write+0x41b/0x11e0 drivers/tty/n_tty.c:2377 iterate_tty_write drivers/tty/tty_io.c:1006 [inline] file_tty_write.constprop.0+0x500/0x9b0 drivers/tty/tty_io.c:1081 tty_write drivers/tty/tty_io.c:1102 [inline] redirected_tty_write drivers/tty/tty_io.c:1125 [inline] redirected_tty_write+0xd4/0x150 drivers/tty/tty_io.c:1105 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x7d3/0x11d0 fs/read_write.c:686 ksys_write+0x12a/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&port_lock_key){-.-.}-{3:3}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:717 [inline] serial8250_console_write+0x181/0x1890 drivers/tty/serial/8250/8250_port.c:3301 console_emit_next_record kernel/printk/printk.c:3111 [inline] console_flush_all+0x801/0xc60 kernel/printk/printk.c:3199 __console_flush_and_unlock kernel/printk/printk.c:3258 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3298 vprintk_emit+0x3d7/0x680 kernel/printk/printk.c:2423 _printk+0xc7/0x100 kernel/printk/printk.c:2448 register_console+0xc2d/0x11b0 kernel/printk/printk.c:4099 univ8250_console_init+0x5f/0x90 drivers/tty/serial/8250/8250_core.c:511 console_init+0x14f/0x680 kernel/printk/printk.c:4298 start_kernel+0x29f/0x4e0 init/main.c:1048 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x148 -> #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 kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x12a6/0x1ce0 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 console_trylock_spinning kernel/printk/printk.c:2021 [inline] vprintk_emit+0x4a4/0x680 kernel/printk/printk.c:2422 _printk+0xc7/0x100 kernel/printk/printk.c:2448 fail_dump lib/fault-inject.c:66 [inline] should_fail_ex+0x4e7/0x640 lib/fault-inject.c:174 strncpy_from_user+0x3b/0x2e0 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:192 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:214 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:223 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:220 bpf_prog_0d6d5ccd463007db+0x64/0x6c bpf_dispatcher_nop_func include/linux/bpf.h:1350 [inline] __bpf_prog_run include/linux/filter.h:721 [inline] bpf_prog_run include/linux/filter.h:728 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline] bpf_trace_run2+0x239/0x590 kernel/trace/bpf_trace.c:2116 __bpf_trace_tlb_flush+0xd1/0x110 include/trace/events/tlb.h:38 __do_trace_tlb_flush include/trace/events/tlb.h:38 [inline] trace_tlb_flush+0xe4/0x160 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x2b1/0x7f0 arch/x86/mm/tlb.c:932 context_switch kernel/sched/core.c:5309 [inline] __schedule+0xf70/0x5de0 kernel/sched/core.c:6929 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7113 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x61/0x80 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] gsmld_write+0xe8/0x150 drivers/tty/n_gsm.c:3789 iterate_tty_write drivers/tty/tty_io.c:1006 [inline] file_tty_write.constprop.0+0x500/0x9b0 drivers/tty/tty_io.c:1081 do_iter_readv_writev+0x65f/0x9e0 fs/read_write.c:827 vfs_writev+0x35f/0xde0 fs/read_write.c:1057 do_writev+0x132/0x340 fs/read_write.c:1103 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x300 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e 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 *** 4 locks held by syz.4.4004/21781: #0: ffff888065b340a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffff888065b34130 (&tty->atomic_write_lock){+.+.}-{4:4}, at: tty_write_lock drivers/tty/tty_io.c:939 [inline] #1: ffff888065b34130 (&tty->atomic_write_lock){+.+.}-{4:4}, at: iterate_tty_write drivers/tty/tty_io.c:958 [inline] #1: ffff888065b34130 (&tty->atomic_write_lock){+.+.}-{4:4}, at: file_tty_write.constprop.0+0x283/0x9b0 drivers/tty/tty_io.c:1081 #2: ffff88802b23a4d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:646 [inline] #2: ffff88802b23a4d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:631 #3: ffffffff8e3c4320 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #3: ffffffff8e3c4320 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #3: ffffffff8e3c4320 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2074 [inline] #3: ffffffff8e3c4320 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run2+0x1bc/0x590 kernel/trace/bpf_trace.c:2116 stack backtrace: CPU: 1 UID: 0 PID: 21781 Comm: syz.4.4004 Not tainted syzkaller #0 PREEMPT(full) 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+0x275/0x350 kernel/locking/lockdep.c:2043 check_noncircular+0x14c/0x170 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 kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x12a6/0x1ce0 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 console_trylock_spinning kernel/printk/printk.c:2021 [inline] vprintk_emit+0x4a4/0x680 kernel/printk/printk.c:2422 _printk+0xc7/0x100 kernel/printk/printk.c:2448 fail_dump lib/fault-inject.c:66 [inline] should_fail_ex+0x4e7/0x640 lib/fault-inject.c:174 strncpy_from_user+0x3b/0x2e0 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:192 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:214 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:223 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:220 bpf_prog_0d6d5ccd463007db+0x64/0x6c bpf_dispatcher_nop_func include/linux/bpf.h:1350 [inline] __bpf_prog_run include/linux/filter.h:721 [inline] bpf_prog_run include/linux/filter.h:728 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline] bpf_trace_run2+0x239/0x590 kernel/trace/bpf_trace.c:2116 __bpf_trace_tlb_flush+0xd1/0x110 include/trace/events/tlb.h:38 __do_trace_tlb_flush include/trace/events/tlb.h:38 [inline] trace_tlb_flush+0xe4/0x160 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x2b1/0x7f0 arch/x86/mm/tlb.c:932 context_switch kernel/sched/core.c:5309 [inline] __schedule+0xf70/0x5de0 kernel/sched/core.c:6929 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7113 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x61/0x80 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] gsmld_write+0xe8/0x150 drivers/tty/n_gsm.c:3789 iterate_tty_write drivers/tty/tty_io.c:1006 [inline] file_tty_write.constprop.0+0x500/0x9b0 drivers/tty/tty_io.c:1081 do_iter_readv_writev+0x65f/0x9e0 fs/read_write.c:827 vfs_writev+0x35f/0xde0 fs/read_write.c:1057 do_writev+0x132/0x340 fs/read_write.c:1103 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x300 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf701d579 Code: Unable to access opcode bytes at 0xf701d54f. RSP: 002b:00000000f540d55c EFLAGS: 00000296 ORIG_RAX: 0000000000000092 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000080000b00 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 CPU: 1 UID: 0 PID: 21781 Comm: syz.4.4004 Not tainted syzkaller #0 PREEMPT(full) 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+0x512/0x640 lib/fault-inject.c:174 strncpy_from_user+0x3b/0x2e0 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:192 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:214 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:223 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:220 bpf_prog_0d6d5ccd463007db+0x64/0x6c bpf_dispatcher_nop_func include/linux/bpf.h:1350 [inline] __bpf_prog_run include/linux/filter.h:721 [inline] bpf_prog_run include/linux/filter.h:728 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline] bpf_trace_run2+0x239/0x590 kernel/trace/bpf_trace.c:2116 __bpf_trace_tlb_flush+0xd1/0x110 include/trace/events/tlb.h:38 __do_trace_tlb_flush include/trace/events/tlb.h:38 [inline] trace_tlb_flush+0xe4/0x160 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x2b1/0x7f0 arch/x86/mm/tlb.c:932 context_switch kernel/sched/core.c:5309 [inline] __schedule+0xf70/0x5de0 kernel/sched/core.c:6929 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7113 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x61/0x80 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] gsmld_write+0xe8/0x150 drivers/tty/n_gsm.c:3789 iterate_tty_write drivers/tty/tty_io.c:1006 [inline] file_tty_write.constprop.0+0x500/0x9b0 drivers/tty/tty_io.c:1081 do_iter_readv_writev+0x65f/0x9e0 fs/read_write.c:827 vfs_writev+0x35f/0xde0 fs/read_write.c:1057 do_writev+0x132/0x340 fs/read_write.c:1103 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x300 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf701d579 Code: Unable to access opcode bytes at 0xf701d54f. RSP: 002b:00000000f540d55c EFLAGS: 00000296 ORIG_RAX: 0000000000000092 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000080000b00 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U]