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.4.4393/17594 is trying to acquire lock: ffffffff8cb1ee60 (console_owner){-...}-{0:0}, at: console_lock_spinning_enable kernel/printk/printk.c:1818 [inline] ffffffff8cb1ee60 (console_owner){-...}-{0:0}, at: console_emit_next_record+0x82d/0xc90 kernel/printk/printk.c:2774 but task is already holding lock: ffff8880b8e3aad8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 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+0x2e/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 raw_spin_rq_lock kernel/sched/sched.h:1355 [inline] rq_lock kernel/sched/sched.h:1645 [inline] task_fork_fair+0x5c/0x350 kernel/sched/fair.c:11901 sched_cgroup_fork+0x32c/0x3c0 kernel/sched/core.c:4685 copy_process+0x24b8/0x4020 kernel/fork.c:2459 kernel_clone+0x225/0x8b0 kernel/fork.c:2757 user_mode_thread+0xda/0x130 kernel/fork.c:2833 rest_init+0x23/0x300 init/main.c:710 start_kernel+0x0/0x539 init/main.c:905 start_kernel+0x490/0x539 init/main.c:1152 secondary_startup_64_no_verify+0xcf/0xdb -> #3 (&p->pi_lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162 try_to_wake_up+0x5c/0x1080 kernel/sched/core.c:4111 __wake_up_common+0x2a4/0x4e0 kernel/sched/wait.c:107 __wake_up_common_lock kernel/sched/wait.c:138 [inline] __wake_up+0x10e/0x190 kernel/sched/wait.c:160 tty_port_default_wakeup+0x9e/0xf0 drivers/tty/tty_port.c:71 serial8250_tx_chars+0x629/0x830 drivers/tty/serial/8250/8250_port.c:1854 serial8250_handle_irq+0x516/0x6d0 drivers/tty/serial/8250/8250_port.c:1961 serial8250_default_handle_irq+0xb4/0x1a0 drivers/tty/serial/8250/8250_port.c:1981 serial8250_interrupt+0x9b/0x1c0 drivers/tty/serial/8250/8250_core.c:126 __handle_irq_event_percpu+0x298/0xa30 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0x87/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x243/0xb20 kernel/irq/chip.c:819 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq arch/x86/kernel/irq.c:233 [inline] __common_interrupt+0xd7/0x1e0 arch/x86/kernel/irq.c:252 common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:242 asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:682 lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5710 lock_is_held include/linux/lockdep.h:283 [inline] mt_locked lib/maple_tree.c:-1 [inline] mt_slot lib/maple_tree.c:814 [inline] mas_slot lib/maple_tree.c:847 [inline] mt_validate_nulls lib/maple_tree.c:7191 [inline] mt_validate+0x43ce/0x4c90 lib/maple_tree.c:7247 validate_mm_mt+0xcd/0x420 mm/mmap.c:295 validate_mm+0xcc/0x2b0 mm/mmap.c:332 remove_mt mm/mmap.c:2322 [inline] do_mas_align_munmap+0xf98/0x1220 mm/mmap.c:2595 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650 __mmap_region mm/mmap.c:2698 [inline] mmap_region+0x6e5/0x1c70 mm/mmap.c:2916 do_mmap+0x958/0xfd0 mm/mmap.c:1436 vm_mmap_pgoff+0x1b2/0x2b0 mm/util.c:520 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #2 (&tty->write_wait){-...}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162 __wake_up_common_lock kernel/sched/wait.c:137 [inline] __wake_up+0xf4/0x190 kernel/sched/wait.c:160 tty_port_default_wakeup+0x9e/0xf0 drivers/tty/tty_port.c:71 serial8250_tx_chars+0x629/0x830 drivers/tty/serial/8250/8250_port.c:1854 serial8250_handle_irq+0x516/0x6d0 drivers/tty/serial/8250/8250_port.c:1961 serial8250_default_handle_irq+0xb4/0x1a0 drivers/tty/serial/8250/8250_port.c:1981 serial8250_interrupt+0x9b/0x1c0 drivers/tty/serial/8250/8250_core.c:126 __handle_irq_event_percpu+0x298/0xa30 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0x87/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x243/0xb20 kernel/irq/chip.c:819 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq arch/x86/kernel/irq.c:233 [inline] __common_interrupt+0xd7/0x1e0 arch/x86/kernel/irq.c:252 common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:242 asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:682 native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] default_idle+0xb/0x10 arch/x86/kernel/process.c:741 default_idle_call+0x84/0xc0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1fc/0x570 kernel/sched/idle.c:303 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401 start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xcf/0xdb -> #1 (&port_lock_key){-...}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162 serial8250_console_write+0x169/0x17a0 drivers/tty/serial/8250/8250_port.c:3432 call_console_driver kernel/printk/printk.c:1977 [inline] console_emit_next_record+0x947/0xc90 kernel/printk/printk.c:2777 console_flush_all kernel/printk/printk.c:-1 [inline] console_unlock+0x223/0x630 kernel/printk/printk.c:2906 vprintk_emit+0x489/0x680 kernel/printk/printk.c:2303 _printk+0xcc/0x110 kernel/printk/printk.c:2328 register_console+0x6c6/0x9c0 kernel/printk/printk.c:3269 univ8250_console_init+0x41/0x43 drivers/tty/serial/8250/8250_core.c:687 console_init+0x1bc/0x78e kernel/printk/printk.c:3359 start_kernel+0x303/0x539 init/main.c:1088 secondary_startup_64_no_verify+0xcf/0xdb -> #0 (console_owner){-...}-{0:0}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 console_lock_spinning_enable kernel/printk/printk.c:1818 [inline] console_emit_next_record+0x84c/0xc90 kernel/printk/printk.c:2774 console_flush_all kernel/printk/printk.c:-1 [inline] console_unlock+0x223/0x630 kernel/printk/printk.c:2906 vprintk_emit+0x489/0x680 kernel/printk/printk.c:2303 _printk+0xcc/0x110 kernel/printk/printk.c:2328 fail_dump lib/fault-inject.c:45 [inline] should_fail_ex+0x37a/0x4d0 lib/fault-inject.c:147 strncpy_from_user+0x32/0x350 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x6d/0x140 mm/maccess.c:186 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:204 [inline] ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:310 [inline] bpf_probe_read_compat_str+0xdd/0x170 kernel/trace/bpf_trace.c:306 bpf_prog_3ba3839c117aeaac+0x38/0x3f bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:596 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x30a/0x3b0 kernel/trace/bpf_trace.c:2324 trace_tlb_flush+0x143/0x190 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x758/0xb10 arch/x86/mm/tlb.c:-1 context_switch kernel/sched/core.c:5229 [inline] __schedule+0xe99/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696 mutex_optimistic_spin kernel/locking/mutex.c:510 [inline] __mutex_lock_common kernel/locking/mutex.c:607 [inline] __mutex_lock+0x25c/0xaf0 kernel/locking/mutex.c:747 dev_ethtool+0x1c1/0x1140 net/ethtool/ioctl.c:3044 dev_ioctl+0x48e/0xea0 net/core/dev_ioctl.c:524 sock_do_ioctl+0x222/0x2f0 net/socket.c:1218 sock_ioctl+0x4ed/0x6e0 net/socket.c:1321 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 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.4.4393/17594: #0: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: dev_ethtool+0x1c1/0x1140 net/ethtool/ioctl.c:3044 #1: ffff8880b8e3aad8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #2: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #2: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #2: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline] #2: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xda/0x3b0 kernel/trace/bpf_trace.c:2324 #3: ffffffff8cb1ef40 (console_lock){+.+.}-{0:0}, at: _printk+0xcc/0x110 kernel/printk/printk.c:2328 stack backtrace: CPU: 0 PID: 17594 Comm: syz.4.4393 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 console_lock_spinning_enable kernel/printk/printk.c:1818 [inline] console_emit_next_record+0x84c/0xc90 kernel/printk/printk.c:2774 console_flush_all kernel/printk/printk.c:-1 [inline] console_unlock+0x223/0x630 kernel/printk/printk.c:2906 vprintk_emit+0x489/0x680 kernel/printk/printk.c:2303 _printk+0xcc/0x110 kernel/printk/printk.c:2328 fail_dump lib/fault-inject.c:45 [inline] should_fail_ex+0x37a/0x4d0 lib/fault-inject.c:147 strncpy_from_user+0x32/0x350 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x6d/0x140 mm/maccess.c:186 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:204 [inline] ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:310 [inline] bpf_probe_read_compat_str+0xdd/0x170 kernel/trace/bpf_trace.c:306 bpf_prog_3ba3839c117aeaac+0x38/0x3f bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:596 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x30a/0x3b0 kernel/trace/bpf_trace.c:2324 trace_tlb_flush+0x143/0x190 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x758/0xb10 arch/x86/mm/tlb.c:-1 context_switch kernel/sched/core.c:5229 [inline] __schedule+0xe99/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696 mutex_optimistic_spin kernel/locking/mutex.c:510 [inline] __mutex_lock_common kernel/locking/mutex.c:607 [inline] __mutex_lock+0x25c/0xaf0 kernel/locking/mutex.c:747 dev_ethtool+0x1c1/0x1140 net/ethtool/ioctl.c:3044 dev_ioctl+0x48e/0xea0 net/core/dev_ioctl.c:524 sock_do_ioctl+0x222/0x2f0 net/socket.c:1218 sock_ioctl+0x4ed/0x6e0 net/socket.c:1321 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd11e38efc9 Code: Unable to access opcode bytes at 0x7fd11e38ef9f. RSP: 002b:00007fd11f1ca038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd11e5e5fa0 RCX: 00007fd11e38efc9 RDX: 0000200000000080 RSI: 0000000000008946 RDI: 0000000000000023 RBP: 00007fd11f1ca090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fd11e5e6038 R14: 00007fd11e5e5fa0 R15: 00007ffc2bce9818 CPU: 0 PID: 17594 Comm: syz.4.4393 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 fail_dump lib/fault-inject.c:52 [inline] should_fail_ex+0x399/0x4d0 lib/fault-inject.c:147 strncpy_from_user+0x32/0x350 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x6d/0x140 mm/maccess.c:186 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:204 [inline] ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:310 [inline] bpf_probe_read_compat_str+0xdd/0x170 kernel/trace/bpf_trace.c:306 bpf_prog_3ba3839c117aeaac+0x38/0x3f bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:596 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x30a/0x3b0 kernel/trace/bpf_trace.c:2324 trace_tlb_flush+0x143/0x190 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x758/0xb10 arch/x86/mm/tlb.c:-1 context_switch kernel/sched/core.c:5229 [inline] __schedule+0xe99/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696 mutex_optimistic_spin kernel/locking/mutex.c:510 [inline] __mutex_lock_common kernel/locking/mutex.c:607 [inline] __mutex_lock+0x25c/0xaf0 kernel/locking/mutex.c:747 dev_ethtool+0x1c1/0x1140 net/ethtool/ioctl.c:3044 dev_ioctl+0x48e/0xea0 net/core/dev_ioctl.c:524 sock_do_ioctl+0x222/0x2f0 net/socket.c:1218 sock_ioctl+0x4ed/0x6e0 net/socket.c:1321 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd11e38efc9 Code: Unable to access opcode bytes at 0x7fd11e38ef9f. RSP: 002b:00007fd11f1ca038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd11e5e5fa0 RCX: 00007fd11e38efc9 RDX: 0000200000000080 RSI: 0000000000008946 RDI: 0000000000000023 RBP: 00007fd11f1ca090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fd11e5e6038 R14: 00007fd11e5e5fa0 R15: 00007ffc2bce9818