FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 0
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
syz.3.1591/12632 is trying to acquire lock:
ffffffff8e138b00 (console_owner){-.-.}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:317 [inline]
ffffffff8e138b00 (console_owner){-.-.}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:428 [inline]
ffffffff8e138b00 (console_owner){-.-.}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:291 [inline]
ffffffff8e138b00 (console_owner){-.-.}-{0:0}, at: console_flush_one_record kernel/printk/printk.c:3194 [inline]
ffffffff8e138b00 (console_owner){-.-.}-{0:0}, at: console_flush_all+0x11a/0xb00 kernel/printk/printk.c:3291

but task is already holding lock:
ffff8880b863abe0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xba/0x150 kernel/sched/core.c:655

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+0x32/0x50 kernel/locking/spinlock.c:378
       raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647
       raw_spin_rq_lock kernel/sched/sched.h:1613 [inline]
       _task_rq_lock+0xbc/0x470 kernel/sched/core.c:747
       cgroup_move_task+0x92/0x2a0 kernel/sched/psi.c:1170
       css_set_move_task+0x658/0x9e0 kernel/cgroup/cgroup.c:948
       cgroup_post_fork+0x1ef/0x7a0 kernel/cgroup/cgroup.c:6910
       copy_process+0x385e/0x3ba0 kernel/fork.c:2462
       kernel_clone+0x21e/0x820 kernel/fork.c:2648
       user_mode_thread+0xdd/0x140 kernel/fork.c:2724
       rest_init+0x23/0x300 init/main.c:725
       start_kernel+0x386/0x3d0 init/main.c:1210
       x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
       x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
       common_startup_64+0x13e/0x147

-> #3 (&p->pi_lock){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
       _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:162
       class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:573 [inline]
       try_to_wake_up+0x67/0x12c0 kernel/sched/core.c:4130
       __wake_up_common kernel/sched/wait.c:108 [inline]
       __wake_up_common_lock+0x137/0x1f0 kernel/sched/wait.c:125
       tty_port_default_wakeup+0xfb/0x170 drivers/tty/tty_port.c:67
       serial8250_tx_chars+0x72e/0x970 drivers/tty/serial/8250/8250_port.c:1719
       serial8250_handle_irq+0x633/0xbb0 drivers/tty/serial/8250/8250_port.c:1827
       serial8250_default_handle_irq+0xbf/0x200 drivers/tty/serial/8250/8250_port.c:1846
       serial8250_interrupt+0x8d/0x180 drivers/tty/serial/8250/8250_core.c:86
       __handle_irq_event_percpu+0x217/0x970 kernel/irq/handle.c:209
       handle_irq_event_percpu kernel/irq/handle.c:246 [inline]
       handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:263
       handle_edge_irq+0x23b/0xa10 kernel/irq/chip.c:855
       generic_handle_irq_desc include/linux/irqdesc.h:186 [inline]
       handle_irq arch/x86/kernel/irq.c:262 [inline]
       call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
       __common_interrupt+0x141/0x1f0 arch/x86/kernel/irq.c:333
       common_interrupt+0xb6/0xe0 arch/x86/kernel/irq.c:326
       asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
       unwind_next_frame+0x4a5/0x23d0 arch/x86/kernel/unwind_orc.c:-1
       arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
       stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
       kasan_save_stack mm/kasan/common.c:57 [inline]
       kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
       poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
       __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
       kasan_kmalloc include/linux/kasan.h:263 [inline]
       __do_kmalloc_node mm/slub.c:5129 [inline]
       __kmalloc_noprof+0x361/0x770 mm/slub.c:5141
       kmalloc_noprof include/linux/slab.h:966 [inline]
       tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
       tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
       tomoyo_check_open_permission+0x1c1/0x3b0 security/tomoyo/file.c:776
       security_file_open+0xb1/0x270 security/security.c:2636
       do_dentry_open+0x384/0x14e0 fs/open.c:926
       vfs_open+0x3b/0x340 fs/open.c:1081
       do_open fs/namei.c:4671 [inline]
       path_openat+0x2de0/0x3840 fs/namei.c:4830
       do_file_open+0x203/0x440 fs/namei.c:4859
       do_sys_openat2+0x105/0x1e0 fs/open.c:1366
       do_sys_open fs/open.c:1372 [inline]
       __do_sys_openat fs/open.c:1388 [inline]
       __se_sys_openat fs/open.c:1383 [inline]
       __x64_sys_openat+0x138/0x170 fs/open.c:1383
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (&tty->write_wait){-.-.}-{3:3}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
       _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:162
       __wake_up_common_lock+0x2f/0x1f0 kernel/sched/wait.c:124
       tty_port_default_wakeup+0xfb/0x170 drivers/tty/tty_port.c:67
       serial8250_tx_chars+0x72e/0x970 drivers/tty/serial/8250/8250_port.c:1719
       serial8250_handle_irq+0x633/0xbb0 drivers/tty/serial/8250/8250_port.c:1827
       serial8250_default_handle_irq+0xbf/0x200 drivers/tty/serial/8250/8250_port.c:1846
       serial8250_interrupt+0x8d/0x180 drivers/tty/serial/8250/8250_core.c:86
       __handle_irq_event_percpu+0x217/0x970 kernel/irq/handle.c:209
       handle_irq_event_percpu kernel/irq/handle.c:246 [inline]
       handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:263
       handle_edge_irq+0x23b/0xa10 kernel/irq/chip.c:855
       generic_handle_irq_desc include/linux/irqdesc.h:186 [inline]
       handle_irq arch/x86/kernel/irq.c:262 [inline]
       call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
       __common_interrupt+0x141/0x1f0 arch/x86/kernel/irq.c:333
       common_interrupt+0xb6/0xe0 arch/x86/kernel/irq.c:326
       asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
       _raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:194
       spin_unlock_irqrestore include/linux/spinlock.h:410 [inline]
       uart_port_unlock_irqrestore include/linux/serial_core.h:788 [inline]
       uart_port_unlock_deref+0x111/0x2f0 drivers/tty/serial/serial_core.c:91
       uart_write+0xe8/0x130 drivers/tty/serial/serial_core.c:634
       process_output_block drivers/tty/n_tty.c:557 [inline]
       n_tty_write+0xd78/0x12a0 drivers/tty/n_tty.c:2366
       iterate_tty_write drivers/tty/tty_io.c:1006 [inline]
       file_tty_write+0x559/0xa20 drivers/tty/tty_io.c:1081
       new_sync_write fs/read_write.c:595 [inline]
       vfs_write+0x5c9/0xb30 fs/read_write.c:688
       ksys_write+0x145/0x250 fs/read_write.c:740
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xec/0xf80 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:132 [inline]
       _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:162
       uart_port_lock_irqsave include/linux/serial_core.h:717 [inline]
       serial8250_console_write+0x155/0x1b60 drivers/tty/serial/8250/8250_port.c:3301
       console_emit_next_record kernel/printk/printk.c:3131 [inline]
       console_flush_one_record kernel/printk/printk.c:3217 [inline]
       console_flush_all+0x713/0xb00 kernel/printk/printk.c:3291
       __console_flush_and_unlock kernel/printk/printk.c:3321 [inline]
       console_unlock+0xbb/0x190 kernel/printk/printk.c:3361
       vprintk_emit+0x47b/0x550 kernel/printk/printk.c:2428
       _printk+0xcf/0x120 kernel/printk/printk.c:2453
       register_console+0xa8b/0xf90 kernel/printk/printk.c:4172
       univ8250_console_init+0x3a/0x70 drivers/tty/serial/8250/8250_core.c:515
       console_init+0xfc/0x3f0 kernel/printk/printk.c:4371
       start_kernel+0x22c/0x3d0 init/main.c:1147
       x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
       x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
       common_startup_64+0x13e/0x147

-> #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+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237
       lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
       console_lock_spinning_enable kernel/printk/printk.c:1902 [inline]
       console_emit_next_record kernel/printk/printk.c:3125 [inline]
       console_flush_one_record kernel/printk/printk.c:3217 [inline]
       console_flush_all+0x6bc/0xb00 kernel/printk/printk.c:3291
       __console_flush_and_unlock kernel/printk/printk.c:3321 [inline]
       console_unlock+0xbb/0x190 kernel/printk/printk.c:3361
       vprintk_emit+0x47b/0x550 kernel/printk/printk.c:2428
       _printk+0xcf/0x120 kernel/printk/printk.c:2453
       fail_dump lib/fault-inject.c:66 [inline]
       should_fail_ex+0x3f5/0x560 lib/fault-inject.c:174
       strncpy_from_user+0x36/0x2c0 lib/strncpy_from_user.c:118
       strncpy_from_user_nofault+0x72/0x150 mm/maccess.c:192
       bpf_trace_copy_string kernel/bpf/helpers.c:755 [inline]
       bpf_bprintf_prepare+0xbbc/0x13d0 kernel/bpf/helpers.c:976
       ____bpf_trace_printk kernel/trace/bpf_trace.c:372 [inline]
       bpf_trace_printk+0xdb/0x190 kernel/trace/bpf_trace.c:362
       bpf_prog_930ede9872f2967c+0x3e/0x44
       bpf_dispatcher_nop_func include/linux/bpf.h:1394 [inline]
       __bpf_prog_run include/linux/filter.h:723 [inline]
       bpf_prog_run include/linux/filter.h:730 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline]
       bpf_trace_run2+0x284/0x4c0 kernel/trace/bpf_trace.c:2116
       __bpf_trace_contention_begin+0xdc/0x130 include/trace/events/lock.h:95
       __traceiter_contention_begin+0x7a/0xb0 include/trace/events/lock.h:95
       __do_trace_contention_begin include/trace/events/lock.h:95 [inline]
       trace_contention_begin+0xfe/0x120 include/trace/events/lock.h:95
       __pv_queued_spin_lock_slowpath+0xf0/0xad0 kernel/locking/qspinlock.c:219
       pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt-spinlock.h:35 [inline]
       queued_spin_lock_slowpath arch/x86/include/asm/paravirt-spinlock.h:66 [inline]
       queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
       do_raw_spin_lock+0x21f/0x290 kernel/locking/spinlock_debug.c:116
       raw_spin_rq_lock_nested+0xba/0x150 kernel/sched/core.c:655
       raw_spin_rq_lock kernel/sched/sched.h:1613 [inline]
       rq_lock kernel/sched/sched.h:1943 [inline]
       __schedule+0x3bf/0x5030 kernel/sched/core.c:6811
       preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234
       irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
       asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
       lock_release+0x2d8/0x3b0 kernel/locking/lockdep.c:5893
       rcu_lock_release include/linux/rcupdate.h:322 [inline]
       rcu_read_unlock include/linux/rcupdate.h:881 [inline]
       class_rcu_destructor include/linux/rcupdate.h:1193 [inline]
       unwind_next_frame+0x1ab1/0x23d0 arch/x86/kernel/unwind_orc.c:695
       arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
       stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
       kasan_save_stack mm/kasan/common.c:57 [inline]
       kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
       unpoison_slab_object mm/kasan/common.c:340 [inline]
       __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
       kasan_slab_alloc include/linux/kasan.h:253 [inline]
       slab_post_alloc_hook mm/slub.c:4411 [inline]
       slab_alloc_node mm/slub.c:4740 [inline]
       kmem_cache_alloc_node_noprof+0x388/0x6a0 mm/slub.c:4792
       __alloc_skb+0x1d5/0x720 net/core/skbuff.c:696
       alloc_skb include/linux/skbuff.h:1383 [inline]
       nlmsg_new include/net/netlink.h:1055 [inline]
       netlink_ack+0x146/0xa50 net/netlink/af_netlink.c:2487
       netlink_rcv_skb+0x28c/0x470 net/netlink/af_netlink.c:2556
       genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
       netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
       netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
       netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
       sock_sendmsg_nosec+0x18f/0x1d0 net/socket.c:737
       __sock_sendmsg net/socket.c:752 [inline]
       ____sys_sendmsg+0x577/0x880 net/socket.c:2610
       ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2664
       __sys_sendmsg net/socket.c:2696 [inline]
       __do_sys_sendmsg net/socket.c:2701 [inline]
       __se_sys_sendmsg net/socket.c:2699 [inline]
       __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2699
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
       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 ***

5 locks held by syz.3.1591/12632:
 #0: ffffffff8f585ab0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffff8880b863abe0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xba/0x150 kernel/sched/core.c:655
 #2: ffffffff8e144c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #2: ffffffff8e144c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #2: ffffffff8e144c60 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2074 [inline]
 #2: ffffffff8e144c60 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run2+0x186/0x4c0 kernel/trace/bpf_trace.c:2116
 #3: ffffffff8e138b60 (console_lock){+.+.}-{0:0}, at: _printk+0xcf/0x120 kernel/printk/printk.c:2453
 #4: ffffffff8e020418 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:317 [inline]
 #4: ffffffff8e020418 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:428 [inline]
 #4: ffffffff8e020418 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:291 [inline]
 #4: ffffffff8e020418 (console_srcu){....}-{0:0}, at: console_flush_one_record kernel/printk/printk.c:3194 [inline]
 #4: ffffffff8e020418 (console_srcu){....}-{0:0}, at: console_flush_all+0x11a/0xb00 kernel/printk/printk.c:3291

stack backtrace:
CPU: 1 UID: 0 PID: 12632 Comm: syz.3.1591 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2043
 check_noncircular+0x12e/0x150 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+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237
 lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
 console_lock_spinning_enable kernel/printk/printk.c:1902 [inline]
 console_emit_next_record kernel/printk/printk.c:3125 [inline]
 console_flush_one_record kernel/printk/printk.c:3217 [inline]
 console_flush_all+0x6bc/0xb00 kernel/printk/printk.c:3291
 __console_flush_and_unlock kernel/printk/printk.c:3321 [inline]
 console_unlock+0xbb/0x190 kernel/printk/printk.c:3361
 vprintk_emit+0x47b/0x550 kernel/printk/printk.c:2428
 _printk+0xcf/0x120 kernel/printk/printk.c:2453
 fail_dump lib/fault-inject.c:66 [inline]
 should_fail_ex+0x3f5/0x560 lib/fault-inject.c:174
 strncpy_from_user+0x36/0x2c0 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x72/0x150 mm/maccess.c:192
 bpf_trace_copy_string kernel/bpf/helpers.c:755 [inline]
 bpf_bprintf_prepare+0xbbc/0x13d0 kernel/bpf/helpers.c:976
 ____bpf_trace_printk kernel/trace/bpf_trace.c:372 [inline]
 bpf_trace_printk+0xdb/0x190 kernel/trace/bpf_trace.c:362
 bpf_prog_930ede9872f2967c+0x3e/0x44
 bpf_dispatcher_nop_func include/linux/bpf.h:1394 [inline]
 __bpf_prog_run include/linux/filter.h:723 [inline]
 bpf_prog_run include/linux/filter.h:730 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline]
 bpf_trace_run2+0x284/0x4c0 kernel/trace/bpf_trace.c:2116
 __bpf_trace_contention_begin+0xdc/0x130 include/trace/events/lock.h:95
 __traceiter_contention_begin+0x7a/0xb0 include/trace/events/lock.h:95
 __do_trace_contention_begin include/trace/events/lock.h:95 [inline]
 trace_contention_begin+0xfe/0x120 include/trace/events/lock.h:95
 __pv_queued_spin_lock_slowpath+0xf0/0xad0 kernel/locking/qspinlock.c:219
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt-spinlock.h:35 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/paravirt-spinlock.h:66 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x21f/0x290 kernel/locking/spinlock_debug.c:116
 raw_spin_rq_lock_nested+0xba/0x150 kernel/sched/core.c:655
 raw_spin_rq_lock kernel/sched/sched.h:1613 [inline]
 rq_lock kernel/sched/sched.h:1943 [inline]
 __schedule+0x3bf/0x5030 kernel/sched/core.c:6811
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234
 irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x2d8/0x3b0 kernel/locking/lockdep.c:5893
Code: 93 04 11 00 00 00 00 eb b5 e8 44 cf bf 09 f7 c3 00 02 00 00 74 b9 65 48 8b 05 64 4d 04 11 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 49 ab c2 09 cc 48 8d 3d 81 c1 07
RSP: 0018:ffffc9000465efe0 EFLAGS: 00000282
RAX: c064783ed052d800 RBX: 0000000000000202 RCX: 0000000000000046
RDX: 0000000000000001 RSI: ffffffff8db8ac15 RDI: ffffffff8be06860
RBP: ffff888033f447b0 R08: ffffc9000465f9b8 R09: 0000000000000000
R10: ffffc9000465f138 R11: fffff520008cbe29 R12: 0000000000000001
R13: 0000000000000001 R14: ffffffff8e144c60 R15: ffff888033f43c80
 rcu_lock_release include/linux/rcupdate.h:322 [inline]
 rcu_read_unlock include/linux/rcupdate.h:881 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1193 [inline]
 unwind_next_frame+0x1ab1/0x23d0 arch/x86/kernel/unwind_orc.c:695
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4411 [inline]
 slab_alloc_node mm/slub.c:4740 [inline]
 kmem_cache_alloc_node_noprof+0x388/0x6a0 mm/slub.c:4792
 __alloc_skb+0x1d5/0x720 net/core/skbuff.c:696
 alloc_skb include/linux/skbuff.h:1383 [inline]
 nlmsg_new include/net/netlink.h:1055 [inline]
 netlink_ack+0x146/0xa50 net/netlink/af_netlink.c:2487
 netlink_rcv_skb+0x28c/0x470 net/netlink/af_netlink.c:2556
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec+0x18f/0x1d0 net/socket.c:737
 __sock_sendmsg net/socket.c:752 [inline]
 ____sys_sendmsg+0x577/0x880 net/socket.c:2610
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2664
 __sys_sendmsg net/socket.c:2696 [inline]
 __do_sys_sendmsg net/socket.c:2701 [inline]
 __se_sys_sendmsg net/socket.c:2699 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2699
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fac9cf8f749
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:00007fac9de28038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fac9d1e5fa0 RCX: 00007fac9cf8f749
RDX: 0000000044004094 RSI: 0000200000000a40 RDI: 0000000000000004
RBP: 00007fac9de28090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fac9d1e6038 R14: 00007fac9d1e5fa0 R15: 00007ffcd60f1d98
 </TASK>
CPU: 1 UID: 0 PID: 12632 Comm: syz.3.1591 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 fail_dump lib/fault-inject.c:73 [inline]
 should_fail_ex+0x414/0x560 lib/fault-inject.c:174
 strncpy_from_user+0x36/0x2c0 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x72/0x150 mm/maccess.c:192
 bpf_trace_copy_string kernel/bpf/helpers.c:755 [inline]
 bpf_bprintf_prepare+0xbbc/0x13d0 kernel/bpf/helpers.c:976
 ____bpf_trace_printk kernel/trace/bpf_trace.c:372 [inline]
 bpf_trace_printk+0xdb/0x190 kernel/trace/bpf_trace.c:362
 bpf_prog_930ede9872f2967c+0x3e/0x44
 bpf_dispatcher_nop_func include/linux/bpf.h:1394 [inline]
 __bpf_prog_run include/linux/filter.h:723 [inline]
 bpf_prog_run include/linux/filter.h:730 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline]
 bpf_trace_run2+0x284/0x4c0 kernel/trace/bpf_trace.c:2116
 __bpf_trace_contention_begin+0xdc/0x130 include/trace/events/lock.h:95
 __traceiter_contention_begin+0x7a/0xb0 include/trace/events/lock.h:95
 __do_trace_contention_begin include/trace/events/lock.h:95 [inline]
 trace_contention_begin+0xfe/0x120 include/trace/events/lock.h:95
 __pv_queued_spin_lock_slowpath+0xf0/0xad0 kernel/locking/qspinlock.c:219
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt-spinlock.h:35 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/paravirt-spinlock.h:66 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x21f/0x290 kernel/locking/spinlock_debug.c:116
 raw_spin_rq_lock_nested+0xba/0x150 kernel/sched/core.c:655
 raw_spin_rq_lock kernel/sched/sched.h:1613 [inline]
 rq_lock kernel/sched/sched.h:1943 [inline]
 __schedule+0x3bf/0x5030 kernel/sched/core.c:6811
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234
 irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x2d8/0x3b0 kernel/locking/lockdep.c:5893
Code: 93 04 11 00 00 00 00 eb b5 e8 44 cf bf 09 f7 c3 00 02 00 00 74 b9 65 48 8b 05 64 4d 04 11 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 49 ab c2 09 cc 48 8d 3d 81 c1 07
RSP: 0018:ffffc9000465efe0 EFLAGS: 00000282
RAX: c064783ed052d800 RBX: 0000000000000202 RCX: 0000000000000046
RDX: 0000000000000001 RSI: ffffffff8db8ac15 RDI: ffffffff8be06860
RBP: ffff888033f447b0 R08: ffffc9000465f9b8 R09: 0000000000000000
R10: ffffc9000465f138 R11: fffff520008cbe29 R12: 0000000000000001
R13: 0000000000000001 R14: ffffffff8e144c60 R15: ffff888033f43c80
 rcu_lock_release include/linux/rcupdate.h:322 [inline]
 rcu_read_unlock include/linux/rcupdate.h:881 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1193 [inline]
 unwind_next_frame+0x1ab1/0x23d0 arch/x86/kernel/unwind_orc.c:695
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4411 [inline]
 slab_alloc_node mm/slub.c:4740 [inline]
 kmem_cache_alloc_node_noprof+0x388/0x6a0 mm/slub.c:4792
 __alloc_skb+0x1d5/0x720 net/core/skbuff.c:696
 alloc_skb include/linux/skbuff.h:1383 [inline]
 nlmsg_new include/net/netlink.h:1055 [inline]
 netlink_ack+0x146/0xa50 net/netlink/af_netlink.c:2487
 netlink_rcv_skb+0x28c/0x470 net/netlink/af_netlink.c:2556
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec+0x18f/0x1d0 net/socket.c:737
 __sock_sendmsg net/socket.c:752 [inline]
 ____sys_sendmsg+0x577/0x880 net/socket.c:2610
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2664
 __sys_sendmsg net/socket.c:2696 [inline]
 __do_sys_sendmsg net/socket.c:2701 [inline]
 __se_sys_sendmsg net/socket.c:2699 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2699
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fac9cf8f749
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:00007fac9de28038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fac9d1e5fa0 RCX: 00007fac9cf8f749
RDX: 0000000044004094 RSI: 0000200000000a40 RDI: 0000000000000004
RBP: 00007fac9de28090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fac9d1e6038 R14: 00007fac9d1e5fa0 R15: 00007ffcd60f1d98
 </TASK>
----------------
Code disassembly (best guess):
   0:	93                   	xchg   %eax,%ebx
   1:	04 11                	add    $0x11,%al
   3:	00 00                	add    %al,(%rax)
   5:	00 00                	add    %al,(%rax)
   7:	eb b5                	jmp    0xffffffbe
   9:	e8 44 cf bf 09       	call   0x9bfcf52
   e:	f7 c3 00 02 00 00    	test   $0x200,%ebx
  14:	74 b9                	je     0xffffffcf
  16:	65 48 8b 05 64 4d 04 	mov    %gs:0x11044d64(%rip),%rax        # 0x11044d82
  1d:	11
  1e:	48 3b 44 24 28       	cmp    0x28(%rsp),%rax
  23:	75 44                	jne    0x69
  25:	fb                   	sti
  26:	48 83 c4 30          	add    $0x30,%rsp
* 2a:	5b                   	pop    %rbx <-- trapping instruction
  2b:	41 5c                	pop    %r12
  2d:	41 5d                	pop    %r13
  2f:	41 5e                	pop    %r14
  31:	41 5f                	pop    %r15
  33:	5d                   	pop    %rbp
  34:	e9 49 ab c2 09       	jmp    0x9c2ab82
  39:	cc                   	int3
  3a:	48                   	rex.W
  3b:	8d                   	.byte 0x8d
  3c:	3d                   	.byte 0x3d
  3d:	81                   	.byte 0x81
  3e:	c1                   	.byte 0xc1
  3f:	07                   	(bad)