syz.0.108[6327] is installing a program with bpf_probe_write_user helper that may corrupt user memory!
syz.0.108[6327] is installing a program with bpf_probe_write_user helper that may corrupt user memory!
syz.0.108[6327] is installing a program with bpf_probe_write_user helper that may corrupt user memory!
FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 0
======================================================
WARNING: possible circular locking dependency detected
6.13.0-rc1-syzkaller-00036-g5076001689e4 #0 Not tainted
------------------------------------------------------
syz.0.108/6327 is trying to acquire lock:
ffffffff8e0c8800 (console_owner){..-.}-{0:0}, at: console_lock_spinning_enable+0x9f/0xd0 kernel/printk/printk.c:1924

but task is already holding lock:
ffff8880b863ebd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline]
ffff8880b863ebd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:591

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:598
       raw_spin_rq_lock kernel/sched/sched.h:1514 [inline]
       task_rq_lock+0xcf/0x3b0 kernel/sched/core.c:700
       cgroup_move_task+0x82/0x250 kernel/sched/psi.c:1161
       css_set_move_task+0x288/0x5f0 kernel/cgroup/cgroup.c:898
       cgroup_post_fork+0x1c6/0x910 kernel/cgroup/cgroup.c:6691
       copy_process+0x50d9/0x8df0 kernel/fork.c:2621
       kernel_clone+0xfd/0x960 kernel/fork.c:2807
       user_mode_thread+0xb4/0xf0 kernel/fork.c:2885
       rest_init+0x23/0x2b0 init/main.c:712
       start_kernel+0x3e4/0x4d0 init/main.c:1102
       x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507
       x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488
       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:551 [inline]
       try_to_wake_up+0xb6/0x1490 kernel/sched/core.c:4205
       __wake_up_common+0x131/0x1e0 kernel/sched/wait.c:89
       __wake_up_common_lock kernel/sched/wait.c:106 [inline]
       __wake_up+0x31/0x60 kernel/sched/wait.c:127
       tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69
       serial8250_tx_chars+0x68e/0x860 drivers/tty/serial/8250/8250_port.c:1840
       serial8250_handle_irq+0x74d/0xc80 drivers/tty/serial/8250/8250_port.c:1948
       serial8250_default_handle_irq+0x9a/0x210 drivers/tty/serial/8250/8250_port.c:1968
       serial8250_interrupt+0x103/0x210 drivers/tty/serial/8250/8250_core.c:86
       __handle_irq_event_percpu+0x229/0x7d0 kernel/irq/handle.c:158
       handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
       handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210
       handle_edge_irq+0x263/0xd10 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+0xdf/0x250 arch/x86/kernel/irq.c:285
       common_interrupt+0xba/0xe0 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:151 [inline]
       _raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
       __debug_check_no_obj_freed lib/debugobjects.c:1108 [inline]
       debug_check_no_obj_freed+0x327/0x600 lib/debugobjects.c:1129
       slab_free_hook mm/slub.c:2269 [inline]
       slab_free mm/slub.c:4598 [inline]
       kmem_cache_free+0x2d4/0x4c0 mm/slub.c:4700
       putname+0x13c/0x180 fs/namei.c:296
       do_sys_openat2+0x160/0x1e0 fs/open.c:1410
       do_sys_open fs/open.c:1417 [inline]
       __do_sys_openat fs/open.c:1433 [inline]
       __se_sys_openat fs/open.c:1428 [inline]
       __x64_sys_openat+0x175/0x210 fs/open.c:1428
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #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:105 [inline]
       __wake_up+0x1c/0x60 kernel/sched/wait.c:127
       tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69
       serial8250_tx_chars+0x68e/0x860 drivers/tty/serial/8250/8250_port.c:1840
       serial8250_handle_irq+0x74d/0xc80 drivers/tty/serial/8250/8250_port.c:1948
       serial8250_default_handle_irq+0x9a/0x210 drivers/tty/serial/8250/8250_port.c:1968
       serial8250_interrupt+0x103/0x210 drivers/tty/serial/8250/8250_core.c:86
       __handle_irq_event_percpu+0x229/0x7d0 kernel/irq/handle.c:158
       handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
       handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210
       handle_edge_irq+0x263/0xd10 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+0xdf/0x250 arch/x86/kernel/irq.c:285
       common_interrupt+0xba/0xe0 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:151 [inline]
       _raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
       spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
       uart_port_unlock_irqrestore include/linux/serial_core.h:786 [inline]
       uart_write+0x2a4/0xb30 drivers/tty/serial/serial_core.c:636
       process_output_block drivers/tty/n_tty.c:574 [inline]
       n_tty_write+0x419/0x1140 drivers/tty/n_tty.c:2389
       iterate_tty_write drivers/tty/tty_io.c:1015 [inline]
       file_tty_write.constprop.0+0x506/0x9a0 drivers/tty/tty_io.c:1090
       tty_write drivers/tty/tty_io.c:1111 [inline]
       redirected_tty_write drivers/tty/tty_io.c:1134 [inline]
       redirected_tty_write+0xcc/0x140 drivers/tty/tty_io.c:1114
       new_sync_write fs/read_write.c:586 [inline]
       vfs_write+0x5ae/0x1150 fs/read_write.c:679
       ksys_write+0x12b/0x250 fs/read_write.c:731
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       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:715 [inline]
       serial8250_console_write+0xb56/0x17c0 drivers/tty/serial/8250/8250_port.c:3371
       console_emit_next_record kernel/printk/printk.c:3122 [inline]
       console_flush_all+0x803/0xc60 kernel/printk/printk.c:3210
       __console_flush_and_unlock kernel/printk/printk.c:3269 [inline]
       console_unlock+0xd9/0x210 kernel/printk/printk.c:3309
       vprintk_emit+0x424/0x6f0 kernel/printk/printk.c:2432
       vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:86
       _printk+0xc8/0x100 kernel/printk/printk.c:2457
       register_console+0xbfd/0x1170 kernel/printk/printk.c:4099
       univ8250_console_init+0x5f/0x90 drivers/tty/serial/8250/8250_core.c:513
       console_init+0x154/0x690 kernel/printk/printk.c:4292
       start_kernel+0x29a/0x4d0 init/main.c:1037
       x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507
       x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488
       common_startup_64+0x13e/0x148

-> #0 (console_owner){..-.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3161 [inline]
       check_prevs_add kernel/locking/lockdep.c:3280 [inline]
       validate_chain kernel/locking/lockdep.c:3904 [inline]
       __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
       lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
       console_lock_spinning_enable+0xb0/0xd0 kernel/printk/printk.c:1924
       console_emit_next_record kernel/printk/printk.c:3116 [inline]
       console_flush_all+0x7ac/0xc60 kernel/printk/printk.c:3210
       __console_flush_and_unlock kernel/printk/printk.c:3269 [inline]
       console_unlock+0xd9/0x210 kernel/printk/printk.c:3309
       vprintk_emit+0x424/0x6f0 kernel/printk/printk.c:2432
       vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:86
       _printk+0xc8/0x100 kernel/printk/printk.c:2457
       fail_dump lib/fault-inject.c:46 [inline]
       should_fail_ex+0x46c/0x5b0 lib/fault-inject.c:154
       __copy_to_user_inatomic include/linux/uaccess.h:132 [inline]
       copy_to_user_nofault+0xac/0x180 mm/maccess.c:156
       ____bpf_probe_write_user kernel/trace/bpf_trace.c:348 [inline]
       bpf_probe_write_user+0xaf/0xf0 kernel/trace/bpf_trace.c:326
       bpf_prog_6303d92f98284ad8+0x44/0x48
       bpf_dispatcher_nop_func include/linux/bpf.h:1290 [inline]
       __bpf_prog_run include/linux/filter.h:701 [inline]
       bpf_prog_run include/linux/filter.h:708 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:2351 [inline]
       bpf_trace_run4+0x245/0x5a0 kernel/trace/bpf_trace.c:2394
       __bpf_trace_sched_switch+0x13e/0x190 include/trace/events/sched.h:222
       trace_sched_switch include/trace/events/sched.h:222 [inline]
       __schedule+0x1b71/0x5ad0 kernel/sched/core.c:6753
       preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7078
       irqentry_exit+0x36/0x90 kernel/entry/common.c:354
       asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
       get_current arch/x86/include/asm/current.h:49 [inline]
       __need_reclaim mm/page_alloc.c:3840 [inline]
       __need_reclaim mm/page_alloc.c:3833 [inline]
       fs_reclaim_release+0x55/0x100 mm/page_alloc.c:3880
       might_alloc include/linux/sched/mm.h:319 [inline]
       slab_pre_alloc_hook mm/slub.c:4055 [inline]
       slab_alloc_node mm/slub.c:4133 [inline]
       __do_kmalloc_node mm/slub.c:4282 [inline]
       __kmalloc_node_track_caller_noprof+0xbc/0x510 mm/slub.c:4302
       memdup_user+0x2a/0xd0 mm/util.c:218
       strndup_user+0x78/0xe0 mm/util.c:277
       copy_mount_string fs/namespace.c:3742 [inline]
       __do_sys_mount fs/namespace.c:4042 [inline]
       __se_sys_mount fs/namespace.c:4034 [inline]
       __x64_sys_mount+0x138/0x320 fs/namespace.c:4034
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 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 ***

5 locks held by syz.0.108/6327:
 #0: ffffffff8e34f060 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:318 [inline]
 #0: ffffffff8e34f060 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:4055 [inline]
 #0: ffffffff8e34f060 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:4133 [inline]
 #0: ffffffff8e34f060 (fs_reclaim){+.+.}-{0:0}, at: __do_kmalloc_node mm/slub.c:4282 [inline]
 #0: ffffffff8e34f060 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_node_track_caller_noprof+0xb5/0x510 mm/slub.c:4302
 #1: ffff8880b863ebd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline]
 #1: ffff8880b863ebd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:591
 #2: ffffffff8e1bb500 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #2: ffffffff8e1bb500 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #2: ffffffff8e1bb500 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2350 [inline]
 #2: ffffffff8e1bb500 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run4+0x1d6/0x5a0 kernel/trace/bpf_trace.c:2394
 #3: ffffffff8e1a8c40 (console_lock){+.+.}-{0:0}, at: vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:86
 #4: ffffffff8e1a8cb0 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:342 [inline]
 #4: ffffffff8e1a8cb0 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:297 [inline]
 #4: ffffffff8e1a8cb0 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:288 [inline]
 #4: ffffffff8e1a8cb0 (console_srcu){....}-{0:0}, at: console_flush_all+0x159/0xc60 kernel/printk/printk.c:3187

stack backtrace:
CPU: 1 UID: 0 PID: 6327 Comm: syz.0.108 Not tainted 6.13.0-rc1-syzkaller-00036-g5076001689e4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_circular_bug+0x419/0x5d0 kernel/locking/lockdep.c:2074
 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2206
 check_prev_add kernel/locking/lockdep.c:3161 [inline]
 check_prevs_add kernel/locking/lockdep.c:3280 [inline]
 validate_chain kernel/locking/lockdep.c:3904 [inline]
 __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
 console_lock_spinning_enable+0xb0/0xd0 kernel/printk/printk.c:1924
 console_emit_next_record kernel/printk/printk.c:3116 [inline]
 console_flush_all+0x7ac/0xc60 kernel/printk/printk.c:3210
 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline]
 console_unlock+0xd9/0x210 kernel/printk/printk.c:3309
 vprintk_emit+0x424/0x6f0 kernel/printk/printk.c:2432
 vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:86
 _printk+0xc8/0x100 kernel/printk/printk.c:2457
 fail_dump lib/fault-inject.c:46 [inline]
 should_fail_ex+0x46c/0x5b0 lib/fault-inject.c:154
 __copy_to_user_inatomic include/linux/uaccess.h:132 [inline]
 copy_to_user_nofault+0xac/0x180 mm/maccess.c:156
 ____bpf_probe_write_user kernel/trace/bpf_trace.c:348 [inline]
 bpf_probe_write_user+0xaf/0xf0 kernel/trace/bpf_trace.c:326
 bpf_prog_6303d92f98284ad8+0x44/0x48
 bpf_dispatcher_nop_func include/linux/bpf.h:1290 [inline]
 __bpf_prog_run include/linux/filter.h:701 [inline]
 bpf_prog_run include/linux/filter.h:708 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2351 [inline]
 bpf_trace_run4+0x245/0x5a0 kernel/trace/bpf_trace.c:2394
 __bpf_trace_sched_switch+0x13e/0x190 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x1b71/0x5ad0 kernel/sched/core.c:6753
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7078
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
RIP: 0010:__need_reclaim mm/page_alloc.c:3840 [inline]
RIP: 0010:__need_reclaim mm/page_alloc.c:3833 [inline]
RIP: 0010:fs_reclaim_release+0x55/0x100 mm/page_alloc.c:3880
Code: f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 a2 00 00 00 8b 45 2c a9 00 00 0c 10 75 6d f6 c7 04 74 4e 65 48 8b 2d 6b ec 14 7e <48> 8d 7d 2c 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f
RSP: 0018:ffffc900030e7db8 EFLAGS: 00000202
RAX: 0000000000400140 RBX: 0000000000102cc0 RCX: ffffc900030e7d58
RDX: 0000000000000000 RSI: ffffffff8b6cdb40 RDI: ffff88802666802c
RBP: ffff888026668000 R08: 0000000000000000 R09: fffffbfff20be07a
R10: ffffffff905f03d7 R11: 0000000000000001 R12: ffff88801b041500
R13: 0000000000102cc0 R14: 0000000000000005 R15: 00000000ffffffff
 might_alloc include/linux/sched/mm.h:319 [inline]
 slab_pre_alloc_hook mm/slub.c:4055 [inline]
 slab_alloc_node mm/slub.c:4133 [inline]
 __do_kmalloc_node mm/slub.c:4282 [inline]
 __kmalloc_node_track_caller_noprof+0xbc/0x510 mm/slub.c:4302
 memdup_user+0x2a/0xd0 mm/util.c:218
 strndup_user+0x78/0xe0 mm/util.c:277
 copy_mount_string fs/namespace.c:3742 [inline]
 __do_sys_mount fs/namespace.c:4042 [inline]
 __se_sys_mount fs/namespace.c:4034 [inline]
 __x64_sys_mount+0x138/0x320 fs/namespace.c:4034
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4021d7ff19
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:00007f4022bd1058 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f4021f46160 RCX: 00007f4021d7ff19
RDX: 0000000020000080 RSI: 0000000020000040 RDI: 00000000200000c0
RBP: 00007f4022bd10a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000109 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 00007f4021f46160 R15: 00007ffd83fc6ab8
 </TASK>
CPU: 1 UID: 0 PID: 6327 Comm: syz.0.108 Not tainted 6.13.0-rc1-syzkaller-00036-g5076001689e4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 fail_dump lib/fault-inject.c:53 [inline]
 should_fail_ex+0x497/0x5b0 lib/fault-inject.c:154
 __copy_to_user_inatomic include/linux/uaccess.h:132 [inline]
 copy_to_user_nofault+0xac/0x180 mm/maccess.c:156
 ____bpf_probe_write_user kernel/trace/bpf_trace.c:348 [inline]
 bpf_probe_write_user+0xaf/0xf0 kernel/trace/bpf_trace.c:326
 bpf_prog_6303d92f98284ad8+0x44/0x48
 bpf_dispatcher_nop_func include/linux/bpf.h:1290 [inline]
 __bpf_prog_run include/linux/filter.h:701 [inline]
 bpf_prog_run include/linux/filter.h:708 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2351 [inline]
 bpf_trace_run4+0x245/0x5a0 kernel/trace/bpf_trace.c:2394
 __bpf_trace_sched_switch+0x13e/0x190 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x1b71/0x5ad0 kernel/sched/core.c:6753
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7078
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
RIP: 0010:__need_reclaim mm/page_alloc.c:3840 [inline]
RIP: 0010:__need_reclaim mm/page_alloc.c:3833 [inline]
RIP: 0010:fs_reclaim_release+0x55/0x100 mm/page_alloc.c:3880
Code: f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 a2 00 00 00 8b 45 2c a9 00 00 0c 10 75 6d f6 c7 04 74 4e 65 48 8b 2d 6b ec 14 7e <48> 8d 7d 2c 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f
RSP: 0018:ffffc900030e7db8 EFLAGS: 00000202
RAX: 0000000000400140 RBX: 0000000000102cc0 RCX: ffffc900030e7d58
RDX: 0000000000000000 RSI: ffffffff8b6cdb40 RDI: ffff88802666802c
RBP: ffff888026668000 R08: 0000000000000000 R09: fffffbfff20be07a
R10: ffffffff905f03d7 R11: 0000000000000001 R12: ffff88801b041500
R13: 0000000000102cc0 R14: 0000000000000005 R15: 00000000ffffffff
 might_alloc include/linux/sched/mm.h:319 [inline]
 slab_pre_alloc_hook mm/slub.c:4055 [inline]
 slab_alloc_node mm/slub.c:4133 [inline]
 __do_kmalloc_node mm/slub.c:4282 [inline]
 __kmalloc_node_track_caller_noprof+0xbc/0x510 mm/slub.c:4302
 memdup_user+0x2a/0xd0 mm/util.c:218
 strndup_user+0x78/0xe0 mm/util.c:277
 copy_mount_string fs/namespace.c:3742 [inline]
 __do_sys_mount fs/namespace.c:4042 [inline]
 __se_sys_mount fs/namespace.c:4034 [inline]
 __x64_sys_mount+0x138/0x320 fs/namespace.c:4034
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4021d7ff19
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:00007f4022bd1058 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f4021f46160 RCX: 00007f4021d7ff19
RDX: 0000000020000080 RSI: 0000000020000040 RDI: 00000000200000c0
RBP: 00007f4022bd10a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000109 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 00007f4021f46160 R15: 00007ffd83fc6ab8
 </TASK>
syz.0.108: attempt to access beyond end of device
nbd0: rw=0, sector=0, nr_sectors = 2 limit=0
befs: (nbd0): unable to read superblock
----------------
Code disassembly (best guess):
   0:	f8                   	clc
   1:	83 e0 07             	and    $0x7,%eax
   4:	83 c0 03             	add    $0x3,%eax
   7:	38 d0                	cmp    %dl,%al
   9:	7c 08                	jl     0x13
   b:	84 d2                	test   %dl,%dl
   d:	0f 85 a2 00 00 00    	jne    0xb5
  13:	8b 45 2c             	mov    0x2c(%rbp),%eax
  16:	a9 00 00 0c 10       	test   $0x100c0000,%eax
  1b:	75 6d                	jne    0x8a
  1d:	f6 c7 04             	test   $0x4,%bh
  20:	74 4e                	je     0x70
  22:	65 48 8b 2d 6b ec 14 	mov    %gs:0x7e14ec6b(%rip),%rbp        # 0x7e14ec95
  29:	7e
* 2a:	48 8d 7d 2c          	lea    0x2c(%rbp),%rdi <-- trapping instruction
  2e:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  35:	fc ff df
  38:	48 89 fa             	mov    %rdi,%rdx
  3b:	48 c1 ea 03          	shr    $0x3,%rdx
  3f:	0f                   	.byte 0xf