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.3.3566/21555 is trying to acquire lock:
ffffffff8df35940 (console_owner){-.-.}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:336 [inline]
ffffffff8df35940 (console_owner){-.-.}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:409 [inline]
ffffffff8df35940 (console_owner){-.-.}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:289 [inline]
ffffffff8df35940 (console_owner){-.-.}-{0:0}, at: console_flush_one_record kernel/printk/printk.c:3192 [inline]
ffffffff8df35940 (console_owner){-.-.}-{0:0}, at: console_flush_all+0x11a/0xb00 kernel/printk/printk.c:3289

but task is already holding lock:
ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:647

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+0x2a/0x140 kernel/sched/core.c:639
       raw_spin_rq_lock kernel/sched/sched.h:1580 [inline]
       task_rq_lock+0xbc/0x470 kernel/sched/core.c:739
       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+0x3614/0x3950 kernel/fork.c:2465
       kernel_clone+0x21e/0x820 kernel/fork.c:2651
       user_mode_thread+0xdd/0x140 kernel/fork.c:2727
       rest_init+0x23/0x300 init/main.c:722
       start_kernel+0x381/0x3d0 init/main.c:1206
       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:110 [inline]
       _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:162
       class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline]
       try_to_wake_up+0x67/0x12b0 kernel/sched/core.c:4106
       __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:211
       handle_irq_event_percpu kernel/irq/handle.c:248 [inline]
       handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:265
       handle_edge_irq+0x23b/0xa10 kernel/irq/chip.c:855
       generic_handle_irq_desc include/linux/irqdesc.h:172 [inline]
       handle_irq arch/x86/kernel/irq.c:255 [inline]
       call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
       __common_interrupt+0x141/0x1f0 arch/x86/kernel/irq.c:326
       common_interrupt+0xb6/0xe0 arch/x86/kernel/irq.c:319
       asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
       tick_nohz_idle_enter+0x1c2/0x260 kernel/time/tick-sched.c:1288
       do_idle+0x8e/0x4d0 kernel/sched/idle.c:278
       cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
       start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
       common_startup_64+0x13e/0x147

-> #2 (&tty->write_wait){-.-.}-{3:3}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [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:211
       handle_irq_event_percpu kernel/irq/handle.c:248 [inline]
       handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:265
       handle_edge_irq+0x23b/0xa10 kernel/irq/chip.c:855
       generic_handle_irq_desc include/linux/irqdesc.h:172 [inline]
       handle_irq arch/x86/kernel/irq.c:255 [inline]
       call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
       __common_interrupt+0x141/0x1f0 arch/x86/kernel/irq.c:326
       common_interrupt+0xb6/0xe0 arch/x86/kernel/irq.c:319
       asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
       native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
       pv_native_safe_halt+0x13/0x20 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+0x73/0xb0 kernel/sched/idle.c:122
       cpuidle_idle_call kernel/sched/idle.c:191 [inline]
       do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
       cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
       start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
       common_startup_64+0x13e/0x147

-> #1 (&port_lock_key){-.-.}-{3:3}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [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:3129 [inline]
       console_flush_one_record kernel/printk/printk.c:3215 [inline]
       console_flush_all+0x713/0xb00 kernel/printk/printk.c:3289
       __console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
       console_unlock+0xbb/0x190 kernel/printk/printk.c:3359
       vprintk_emit+0x47b/0x550 kernel/printk/printk.c:2426
       _printk+0xcf/0x120 kernel/printk/printk.c:2451
       register_console+0xa8b/0xf90 kernel/printk/printk.c:4170
       univ8250_console_init+0x3a/0x70 drivers/tty/serial/8250/8250_core.c:515
       console_init+0xfc/0x3f0 kernel/printk/printk.c:4369
       start_kernel+0x227/0x3d0 init/main.c:1143
       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:1900 [inline]
       console_emit_next_record kernel/printk/printk.c:3123 [inline]
       console_flush_one_record kernel/printk/printk.c:3215 [inline]
       console_flush_all+0x6bc/0xb00 kernel/printk/printk.c:3289
       __console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
       console_unlock+0xbb/0x190 kernel/printk/printk.c:3359
       vprintk_emit+0x47b/0x550 kernel/printk/printk.c:2426
       _printk+0xcf/0x120 kernel/printk/printk.c:2451
       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:1378 [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
       __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+0xf0/0xb60 kernel/locking/qspinlock.c:219
       pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:557 [inline]
       queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51
       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+0xad/0x140 kernel/sched/core.c:647
       raw_spin_rq_lock kernel/sched/sched.h:1580 [inline]
       rq_lock kernel/sched/sched.h:1907 [inline]
       __schedule+0x3c4/0x4fd0 kernel/sched/core.c:6772
       preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7194
       irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
       asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
       memset+0xf/0x20 arch/x86/lib/memset_64.S:37
       unwind_next_frame+0xeae/0x23d0 arch/x86/kernel/unwind_orc.c:607
       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]
       __kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5776
       kmalloc_noprof include/linux/slab.h:957 [inline]
       kzalloc_noprof include/linux/slab.h:1094 [inline]
       sctp_auth_shkey_create net/sctp/auth.c:85 [inline]
       sctp_auth_asoc_copy_shkeys+0x14e/0x5a0 net/sctp/auth.c:364
       sctp_association_init net/sctp/associola.c:256 [inline]
       sctp_association_new+0x15d3/0x25e0 net/sctp/associola.c:296
       sctp_connect_new_asoc+0x2c5/0x690 net/sctp/socket.c:1092
       sctp_sendmsg_new_asoc net/sctp/socket.c:1692 [inline]
       sctp_sendmsg+0x155c/0x2840 net/sctp/socket.c:2003
       sock_sendmsg_nosec net/socket.c:727 [inline]
       __sock_sendmsg+0x19c/0x270 net/socket.c:742
       __sys_sendto+0x3bd/0x520 net/socket.c:2206
       __do_sys_sendto net/socket.c:2213 [inline]
       __se_sys_sendto net/socket.c:2209 [inline]
       __x64_sys_sendto+0xde/0x100 net/socket.c:2209
       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 ***

6 locks held by syz.3.3566/21555:
 #0: ffff88802fed7160 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1700 [inline]
 #0: ffff88802fed7160 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sctp_sendmsg+0xb97/0x2840 net/sctp/socket.c:1969
 #1: ffffffff8df41ae0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #1: ffffffff8df41ae0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #1: ffffffff8df41ae0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
 #1: ffffffff8df41ae0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa5/0x23d0 arch/x86/kernel/unwind_orc.c:495
 #2: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:647
 #3: ffffffff8df41ae0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #3: ffffffff8df41ae0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #3: ffffffff8df41ae0 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2074 [inline]
 #3: ffffffff8df41ae0 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run2+0x186/0x4c0 kernel/trace/bpf_trace.c:2116
 #4: ffffffff8df359a0 (console_lock){+.+.}-{0:0}, at: _printk+0xcf/0x120 kernel/printk/printk.c:2451
 #5: ffffffff8de1d258 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:336 [inline]
 #5: ffffffff8de1d258 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:409 [inline]
 #5: ffffffff8de1d258 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:289 [inline]
 #5: ffffffff8de1d258 (console_srcu){....}-{0:0}, at: console_flush_one_record kernel/printk/printk.c:3192 [inline]
 #5: ffffffff8de1d258 (console_srcu){....}-{0:0}, at: console_flush_all+0x11a/0xb00 kernel/printk/printk.c:3289

stack backtrace:
CPU: 1 UID: 0 PID: 21555 Comm: syz.3.3566 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:1900 [inline]
 console_emit_next_record kernel/printk/printk.c:3123 [inline]
 console_flush_one_record kernel/printk/printk.c:3215 [inline]
 console_flush_all+0x6bc/0xb00 kernel/printk/printk.c:3289
 __console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
 console_unlock+0xbb/0x190 kernel/printk/printk.c:3359
 vprintk_emit+0x47b/0x550 kernel/printk/printk.c:2426
 _printk+0xcf/0x120 kernel/printk/printk.c:2451
 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:1378 [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
 __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+0xf0/0xb60 kernel/locking/qspinlock.c:219
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:557 [inline]
 queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51
 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+0xad/0x140 kernel/sched/core.c:647
 raw_spin_rq_lock kernel/sched/sched.h:1580 [inline]
 rq_lock kernel/sched/sched.h:1907 [inline]
 __schedule+0x3c4/0x4fd0 kernel/sched/core.c:6772
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7194
 irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:memset+0xf/0x20 arch/x86/lib/memset_64.S:38
Code: 44 88 1f e9 ee ca b5 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 49 89 f9 40 88 f0 48 89 d1 <f3> aa 4c 89 c8 e9 c2 ca b5 f5 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90003e4f390 EFLAGS: 00000202
RAX: ffffc90003e4f800 RBX: ffffc90003e4f4a0 RCX: 000000000000000f
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90003e4f4b9
RBP: dffffc0000000000 R08: ffffc90003e4f4c7 R09: ffffc90003e4f4b8
R10: dffffc0000000000 R11: fffff520007c9e99 R12: ffffc90003e4f4b8
R13: 1ffff920007c9e8f R14: ffffc90003e4f468 R15: ffffc90003e4f4b0
 unwind_next_frame+0xeae/0x23d0 arch/x86/kernel/unwind_orc.c:607
 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]
 __kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5776
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 sctp_auth_shkey_create net/sctp/auth.c:85 [inline]
 sctp_auth_asoc_copy_shkeys+0x14e/0x5a0 net/sctp/auth.c:364
 sctp_association_init net/sctp/associola.c:256 [inline]
 sctp_association_new+0x15d3/0x25e0 net/sctp/associola.c:296
 sctp_connect_new_asoc+0x2c5/0x690 net/sctp/socket.c:1092
 sctp_sendmsg_new_asoc net/sctp/socket.c:1692 [inline]
 sctp_sendmsg+0x155c/0x2840 net/sctp/socket.c:2003
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x19c/0x270 net/socket.c:742
 __sys_sendto+0x3bd/0x520 net/socket.c:2206
 __do_sys_sendto net/socket.c:2213 [inline]
 __se_sys_sendto net/socket.c:2209 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2209
 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: 0033:0x7f5bb578f749
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:00007f5bb6612038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f5bb59e5fa0 RCX: 00007f5bb578f749
RDX: 0000000000034000 RSI: 0000200000847fff RDI: 0000000000000003
RBP: 00007f5bb6612090 R08: 000020000005ffe4 R09: 000000000000001c
R10: 00000000000000e0 R11: 0000000000000246 R12: 0000000000000001
R13: 00007f5bb59e6038 R14: 00007f5bb59e5fa0 R15: 00007fff8624adc8
 </TASK>
CPU: 1 UID: 0 PID: 21555 Comm: syz.3.3566 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:1378 [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
 __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+0xf0/0xb60 kernel/locking/qspinlock.c:219
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:557 [inline]
 queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51
 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+0xad/0x140 kernel/sched/core.c:647
 raw_spin_rq_lock kernel/sched/sched.h:1580 [inline]
 rq_lock kernel/sched/sched.h:1907 [inline]
 __schedule+0x3c4/0x4fd0 kernel/sched/core.c:6772
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7194
 irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:memset+0xf/0x20 arch/x86/lib/memset_64.S:38
Code: 44 88 1f e9 ee ca b5 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 49 89 f9 40 88 f0 48 89 d1 <f3> aa 4c 89 c8 e9 c2 ca b5 f5 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90003e4f390 EFLAGS: 00000202
RAX: ffffc90003e4f800 RBX: ffffc90003e4f4a0 RCX: 000000000000000f
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90003e4f4b9
RBP: dffffc0000000000 R08: ffffc90003e4f4c7 R09: ffffc90003e4f4b8
R10: dffffc0000000000 R11: fffff520007c9e99 R12: ffffc90003e4f4b8
R13: 1ffff920007c9e8f R14: ffffc90003e4f468 R15: ffffc90003e4f4b0
 unwind_next_frame+0xeae/0x23d0 arch/x86/kernel/unwind_orc.c:607
 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]
 __kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5776
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 sctp_auth_shkey_create net/sctp/auth.c:85 [inline]
 sctp_auth_asoc_copy_shkeys+0x14e/0x5a0 net/sctp/auth.c:364
 sctp_association_init net/sctp/associola.c:256 [inline]
 sctp_association_new+0x15d3/0x25e0 net/sctp/associola.c:296
 sctp_connect_new_asoc+0x2c5/0x690 net/sctp/socket.c:1092
 sctp_sendmsg_new_asoc net/sctp/socket.c:1692 [inline]
 sctp_sendmsg+0x155c/0x2840 net/sctp/socket.c:2003
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x19c/0x270 net/socket.c:742
 __sys_sendto+0x3bd/0x520 net/socket.c:2206
 __do_sys_sendto net/socket.c:2213 [inline]
 __se_sys_sendto net/socket.c:2209 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2209
 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: 0033:0x7f5bb578f749
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:00007f5bb6612038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f5bb59e5fa0 RCX: 00007f5bb578f749
RDX: 0000000000034000 RSI: 0000200000847fff RDI: 0000000000000003
RBP: 00007f5bb6612090 R08: 000020000005ffe4 R09: 000000000000001c
R10: 00000000000000e0 R11: 0000000000000246 R12: 0000000000000001
R13: 00007f5bb59e6038 R14: 00007f5bb59e5fa0 R15: 00007fff8624adc8
 </TASK>
----------------
Code disassembly (best guess):
   0:	44 88 1f             	mov    %r11b,(%rdi)
   3:	e9 ee ca b5 f5       	jmp    0xf5b5caf6
   8:	cc                   	int3
   9:	cc                   	int3
   a:	cc                   	int3
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	f3 0f 1e fa          	endbr64
  1f:	66 90                	xchg   %ax,%ax
  21:	49 89 f9             	mov    %rdi,%r9
  24:	40 88 f0             	mov    %sil,%al
  27:	48 89 d1             	mov    %rdx,%rcx
* 2a:	f3 aa                	rep stos %al,%es:(%rdi) <-- trapping instruction
  2c:	4c 89 c8             	mov    %r9,%rax
  2f:	e9 c2 ca b5 f5       	jmp    0xf5b5caf6
  34:	90                   	nop
  35:	90                   	nop
  36:	90                   	nop
  37:	90                   	nop
  38:	90                   	nop
  39:	90                   	nop
  3a:	90                   	nop
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop