FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 0
======================================================
WARNING: possible circular locking dependency detected
6.10.0-rc2-syzkaller-00797-ga12978712d90 #0 Not tainted
------------------------------------------------------
syz.2.1369/8740 is trying to acquire lock:
ffffffff8e328140 (console_owner){-...}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:334 [inline]
ffffffff8e328140 (console_owner){-...}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:232 [inline]
ffffffff8e328140 (console_owner){-...}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:286 [inline]
ffffffff8e328140 (console_owner){-...}-{0:0}, at: console_flush_all+0x152/0xfd0 kernel/printk/printk.c:2986

but task is already holding lock:
ffff8880b943e798 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&rq->__lock){-.-.}-{2:2}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
       _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378
       raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559
       raw_spin_rq_lock kernel/sched/sched.h:1406 [inline]
       rq_lock kernel/sched/sched.h:1702 [inline]
       task_fork_fair+0x61/0x1e0 kernel/sched/fair.c:12710
       sched_cgroup_fork+0x37c/0x410 kernel/sched/core.c:4844
       copy_process+0x2217/0x3dc0 kernel/fork.c:2499
       kernel_clone+0x226/0x8f0 kernel/fork.c:2797
       user_mode_thread+0x132/0x1a0 kernel/fork.c:2875
       rest_init+0x23/0x300 init/main.c:712
       start_kernel+0x47a/0x500 init/main.c:1103
       x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507
       x86_64_start_kernel+0x99/0xa0 arch/x86/kernel/head64.c:488
       common_startup_64+0x13e/0x147

-> #3 (&p->pi_lock){-.-.}-{2:2}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
       class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:553 [inline]
       try_to_wake_up+0xb0/0x1470 kernel/sched/core.c:4262
       __wake_up_common kernel/sched/wait.c:89 [inline]
       __wake_up_common_lock+0x130/0x1e0 kernel/sched/wait.c:106
       tty_port_default_wakeup+0xa6/0xf0 drivers/tty/tty_port.c:69
       serial8250_tx_chars+0x6e2/0x930 drivers/tty/serial/8250/8250_port.c:1821
       serial8250_handle_irq+0x558/0x710 drivers/tty/serial/8250/8250_port.c:1929
       serial8250_default_handle_irq+0xd1/0x1f0 drivers/tty/serial/8250/8250_port.c:1949
       serial8250_interrupt+0xa9/0x1f0 drivers/tty/serial/8250/8250_core.c:130
       __handle_irq_event_percpu+0x29a/0xa80 kernel/irq/handle.c:158
       handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
       handle_irq_event+0x89/0x1f0 kernel/irq/handle.c:210
       handle_edge_irq+0x25f/0xc20 kernel/irq/chip.c:831
       generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
       handle_irq arch/x86/kernel/irq.c:247 [inline]
       call_irq_handler arch/x86/kernel/irq.c:259 [inline]
       __common_interrupt+0x136/0x230 arch/x86/kernel/irq.c:285
       common_interrupt+0xa5/0xd0 arch/x86/kernel/irq.c:278
       asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
       pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:589 [inline]
       queued_spin_unlock arch/x86/include/asm/qspinlock.h:57 [inline]
       do_raw_spin_unlock+0x118/0x8b0 kernel/locking/spinlock_debug.c:142
       __raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline]
       _raw_spin_unlock+0x1e/0x50 kernel/locking/spinlock.c:186
       fast_dput+0x1e1/0x420
       dput+0xe8/0x2b0 fs/dcache.c:839
       __fput+0x68c/0x8b0 fs/file_table.c:430
       __do_sys_close fs/open.c:1555 [inline]
       __se_sys_close fs/open.c:1540 [inline]
       __x64_sys_close+0x7f/0x110 fs/open.c:1540
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (&tty->write_wait){-.-.}-{2:2}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
       __wake_up_common_lock+0x25/0x1e0 kernel/sched/wait.c:105
       tty_port_default_wakeup+0xa6/0xf0 drivers/tty/tty_port.c:69
       serial8250_tx_chars+0x6e2/0x930 drivers/tty/serial/8250/8250_port.c:1821
       serial8250_handle_irq+0x558/0x710 drivers/tty/serial/8250/8250_port.c:1929
       serial8250_default_handle_irq+0xd1/0x1f0 drivers/tty/serial/8250/8250_port.c:1949
       serial8250_interrupt+0xa9/0x1f0 drivers/tty/serial/8250/8250_core.c:130
       __handle_irq_event_percpu+0x29a/0xa80 kernel/irq/handle.c:158
       handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
       handle_irq_event+0x89/0x1f0 kernel/irq/handle.c:210
       handle_edge_irq+0x25f/0xc20 kernel/irq/chip.c:831
       generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
       handle_irq arch/x86/kernel/irq.c:247 [inline]
       call_irq_handler arch/x86/kernel/irq.c:259 [inline]
       __common_interrupt+0x136/0x230 arch/x86/kernel/irq.c:285
       common_interrupt+0xa5/0xd0 arch/x86/kernel/irq.c:278
       asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
       _raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194
       spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
       uart_port_unlock_irqrestore include/linux/serial_core.h:669 [inline]
       uart_write+0x16c/0x320 drivers/tty/serial/serial_core.c:634
       process_output_block drivers/tty/n_tty.c:574 [inline]
       n_tty_write+0xd6a/0x1230 drivers/tty/n_tty.c:2379
       iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
       file_tty_write+0x54f/0x9b0 drivers/tty/tty_io.c:1096
       new_sync_write fs/read_write.c:497 [inline]
       vfs_write+0xa72/0xc90 fs/read_write.c:590
       ksys_write+0x1a0/0x2c0 fs/read_write.c:643
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&port_lock_key){-.-.}-{2:2}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
       uart_port_lock_irqsave include/linux/serial_core.h:618 [inline]
       serial8250_console_write+0x1a8/0x1770 drivers/tty/serial/8250/8250_port.c:3352
       console_emit_next_record kernel/printk/printk.c:2928 [inline]
       console_flush_all+0x867/0xfd0 kernel/printk/printk.c:2994
       console_unlock+0x13b/0x4d0 kernel/printk/printk.c:3063
       vprintk_emit+0x5a6/0x770 kernel/printk/printk.c:2345
       _printk+0xd5/0x120 kernel/printk/printk.c:2370
       register_console+0x722/0xce0 kernel/printk/printk.c:3596
       univ8250_console_init+0x49/0x50 drivers/tty/serial/8250/8250_core.c:719
       console_init+0x1b8/0x6f0 kernel/printk/printk.c:3742
       start_kernel+0x2d3/0x500 init/main.c:1038
       x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507
       x86_64_start_kernel+0x99/0xa0 arch/x86/kernel/head64.c:488
       common_startup_64+0x13e/0x147

-> #0 (console_owner){-...}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869
       __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
       console_lock_spinning_enable kernel/printk/printk.c:1870 [inline]
       console_emit_next_record kernel/printk/printk.c:2922 [inline]
       console_flush_all+0x810/0xfd0 kernel/printk/printk.c:2994
       console_unlock+0x13b/0x4d0 kernel/printk/printk.c:3063
       vprintk_emit+0x5a6/0x770 kernel/printk/printk.c:2345
       _printk+0xd5/0x120 kernel/printk/printk.c:2370
       fail_dump lib/fault-inject.c:45 [inline]
       should_fail_ex+0x391/0x4e0 lib/fault-inject.c:153
       __copy_to_user_inatomic include/linux/uaccess.h:123 [inline]
       copy_to_user_nofault+0x86/0x140 mm/maccess.c:149
       bpf_prog_42b0bc03b33f5c41+0x47/0x4d
       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+0x334/0x590 kernel/trace/bpf_trace.c:2449
       __traceiter_sched_switch+0x98/0xd0 include/trace/events/sched.h:222
       trace_sched_switch include/trace/events/sched.h:222 [inline]
       __schedule+0x2587/0x4a20 kernel/sched/core.c:6742
       __schedule_loop kernel/sched/core.c:6822 [inline]
       schedule+0x14b/0x320 kernel/sched/core.c:6837
       synchronize_rcu_expedited+0x684/0x830 kernel/rcu/tree_exp.h:954
       synchronize_rcu+0x11b/0x360 kernel/rcu/tree.c:3986
       bpf_dispatcher_update kernel/bpf/dispatcher.c:131 [inline]
       bpf_dispatcher_change_prog+0xe61/0xf10 kernel/bpf/dispatcher.c:167
       bpf_prog_test_run_xdp+0x75c/0x11b0 net/bpf/test_run.c:1304
       bpf_prog_test_run+0x33a/0x3b0 kernel/bpf/syscall.c:4313
       __sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5728
       __do_sys_bpf kernel/bpf/syscall.c:5817 [inline]
       __se_sys_bpf kernel/bpf/syscall.c:5815 [inline]
       __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5815
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 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_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 ***

6 locks held by syz.2.1369/8740:
 #0: ffffffff8f5e9da8 (bpf_dispatcher_xdp.mutex){+.+.}-{3:3}, at: bpf_dispatcher_change_prog+0xa0/0xf10 kernel/bpf/dispatcher.c:146
 #1: ffffffff8e339378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
 #1: ffffffff8e339378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:939
 #2: ffff8880b943e798 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559
 #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
 #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
 #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2405 [inline]
 #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x244/0x590 kernel/trace/bpf_trace.c:2449
 #4: ffffffff8e20fa60 (console_lock){+.+.}-{0:0}, at: _printk+0xd5/0x120 kernel/printk/printk.c:2370
 #5: ffffffff8e20f690 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:334 [inline]
 #5: ffffffff8e20f690 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:232 [inline]
 #5: ffffffff8e20f690 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:286 [inline]
 #5: ffffffff8e20f690 (console_srcu){....}-{0:0}, at: console_flush_all+0x152/0xfd0 kernel/printk/printk.c:2986

stack backtrace:
CPU: 0 PID: 8740 Comm: syz.2.1369 Not tainted 6.10.0-rc2-syzkaller-00797-ga12978712d90 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869
 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
 console_lock_spinning_enable kernel/printk/printk.c:1870 [inline]
 console_emit_next_record kernel/printk/printk.c:2922 [inline]
 console_flush_all+0x810/0xfd0 kernel/printk/printk.c:2994
 console_unlock+0x13b/0x4d0 kernel/printk/printk.c:3063
 vprintk_emit+0x5a6/0x770 kernel/printk/printk.c:2345
 _printk+0xd5/0x120 kernel/printk/printk.c:2370
 fail_dump lib/fault-inject.c:45 [inline]
 should_fail_ex+0x391/0x4e0 lib/fault-inject.c:153
 __copy_to_user_inatomic include/linux/uaccess.h:123 [inline]
 copy_to_user_nofault+0x86/0x140 mm/maccess.c:149
 bpf_prog_42b0bc03b33f5c41+0x47/0x4d
 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+0x334/0x590 kernel/trace/bpf_trace.c:2449
 __traceiter_sched_switch+0x98/0xd0 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x2587/0x4a20 kernel/sched/core.c:6742
 __schedule_loop kernel/sched/core.c:6822 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6837
 synchronize_rcu_expedited+0x684/0x830 kernel/rcu/tree_exp.h:954
 synchronize_rcu+0x11b/0x360 kernel/rcu/tree.c:3986
 bpf_dispatcher_update kernel/bpf/dispatcher.c:131 [inline]
 bpf_dispatcher_change_prog+0xe61/0xf10 kernel/bpf/dispatcher.c:167
 bpf_prog_test_run_xdp+0x75c/0x11b0 net/bpf/test_run.c:1304
 bpf_prog_test_run+0x33a/0x3b0 kernel/bpf/syscall.c:4313
 __sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5728
 __do_sys_bpf kernel/bpf/syscall.c:5817 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5815 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5815
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2740f75b99
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:00007f2741e28048 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f2741103fa0 RCX: 00007f2740f75b99
RDX: 0000000000000048 RSI: 0000000020000600 RDI: 000000000000000a
RBP: 00007f2741e280a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 000000000000000b R14: 00007f2741103fa0 R15: 00007ffe168dc2c8
 </TASK>
CPU: 0 PID: 8740 Comm: syz.2.1369 Not tainted 6.10.0-rc2-syzkaller-00797-ga12978712d90 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail_ex+0x3b0/0x4e0 lib/fault-inject.c:153
 __copy_to_user_inatomic include/linux/uaccess.h:123 [inline]
 copy_to_user_nofault+0x86/0x140 mm/maccess.c:149
 bpf_prog_42b0bc03b33f5c41+0x47/0x4d
 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+0x334/0x590 kernel/trace/bpf_trace.c:2449
 __traceiter_sched_switch+0x98/0xd0 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x2587/0x4a20 kernel/sched/core.c:6742
 __schedule_loop kernel/sched/core.c:6822 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6837
 synchronize_rcu_expedited+0x684/0x830 kernel/rcu/tree_exp.h:954
 synchronize_rcu+0x11b/0x360 kernel/rcu/tree.c:3986
 bpf_dispatcher_update kernel/bpf/dispatcher.c:131 [inline]
 bpf_dispatcher_change_prog+0xe61/0xf10 kernel/bpf/dispatcher.c:167
 bpf_prog_test_run_xdp+0x75c/0x11b0 net/bpf/test_run.c:1304
 bpf_prog_test_run+0x33a/0x3b0 kernel/bpf/syscall.c:4313
 __sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5728
 __do_sys_bpf kernel/bpf/syscall.c:5817 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5815 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5815
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2740f75b99
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:00007f2741e28048 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f2741103fa0 RCX: 00007f2740f75b99
RDX: 0000000000000048 RSI: 0000000020000600 RDI: 000000000000000a
RBP: 00007f2741e280a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 000000000000000b R14: 00007f2741103fa0 R15: 00007ffe168dc2c8
 </TASK>