RDX: 00000000ffffff0b RSI: 0000000020c34fff RDI: 0000000000000003
RBP: 00007ff4c6da81d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffea9d14eaf R14: 00007ff4c6da8300 R15: 0000000000022000
======================================================
WARNING: possible circular locking dependency detected
4.14.228-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.4/17215 is trying to acquire lock:
 (console_owner){-.-.}, at: [<ffffffff8143ee6a>] console_trylock_spinning kernel/printk/printk.c:1658 [inline]
 (console_owner){-.-.}, at: [<ffffffff8143ee6a>] vprintk_emit+0x32a/0x620 kernel/printk/printk.c:1922

but task is already holding lock:
 (&(&port->lock)->rlock){-.-.}, at: [<ffffffff83552e8b>] pty_write+0xdb/0x1d0 drivers/tty/pty.c:120

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&(&port->lock)->rlock){-.-.}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:160
       tty_port_tty_get+0x1d/0x80 drivers/tty/tty_port.c:288
       tty_port_default_wakeup+0x11/0x40 drivers/tty/tty_port.c:46
       serial8250_tx_chars+0x3fe/0xbf0 drivers/tty/serial/8250/8250_port.c:1810
       serial8250_handle_irq.part.0+0x28d/0x330 drivers/tty/serial/8250/8250_port.c:1897
       serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1870 [inline]
       serial8250_default_handle_irq+0x8a/0x1f0 drivers/tty/serial/8250/8250_port.c:1913
       serial8250_interrupt+0xf3/0x210 drivers/tty/serial/8250/8250_core.c:129
       __handle_irq_event_percpu+0xee/0x7f0 kernel/irq/handle.c:147
       handle_irq_event_percpu kernel/irq/handle.c:187 [inline]
       handle_irq_event+0xf0/0x250 kernel/irq/handle.c:204
       handle_edge_irq+0x224/0xc40 kernel/irq/chip.c:770
       generic_handle_irq_desc include/linux/irqdesc.h:159 [inline]
       handle_irq+0x35/0x50 arch/x86/kernel/irq_64.c:87
       do_IRQ+0x93/0x1d0 arch/x86/kernel/irq.c:230
       ret_from_intr+0x0/0x1e
       native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60
       arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
       default_idle+0x47/0x370 arch/x86/kernel/process.c:558
       cpuidle_idle_call kernel/sched/idle.c:156 [inline]
       do_idle+0x250/0x3c0 kernel/sched/idle.c:246
       cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:351
       start_secondary+0x4db/0x670 arch/x86/kernel/smpboot.c:272
       secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:240

-> #1 (&port_lock_key){-.-.}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:160
       serial8250_console_write+0x7a7/0x9d0 drivers/tty/serial/8250/8250_port.c:3253
       call_console_drivers kernel/printk/printk.c:1725 [inline]
       console_unlock+0x99d/0xf20 kernel/printk/printk.c:2400
       vprintk_emit+0x224/0x620 kernel/printk/printk.c:1923
       vprintk_func+0x58/0x160 kernel/printk/printk_safe.c:409
       printk+0x9e/0xbc kernel/printk/printk.c:1996
       register_console+0x6f4/0xad0 kernel/printk/printk.c:2719
       univ8250_console_init+0x2f/0x3a drivers/tty/serial/8250/8250_core.c:691
       console_init+0x46/0x53 kernel/printk/printk.c:2800
       start_kernel+0x52e/0x770 init/main.c:634
       secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:240

-> #0 (console_owner){-.-.}:
       lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
       console_trylock_spinning kernel/printk/printk.c:1679 [inline]
       vprintk_emit+0x367/0x620 kernel/printk/printk.c:1922
       vprintk_func+0x58/0x160 kernel/printk/printk_safe.c:409
       printk+0x9e/0xbc kernel/printk/printk.c:1996
       fail_dump lib/fault-inject.c:44 [inline]
       should_fail.cold+0xdf/0x149 lib/fault-inject.c:149
       should_failslab+0xd6/0x130 mm/failslab.c:32
       slab_pre_alloc_hook mm/slab.h:421 [inline]
       slab_alloc mm/slab.c:3376 [inline]
       __do_kmalloc mm/slab.c:3718 [inline]
       __kmalloc+0x6d/0x400 mm/slab.c:3729
       kmalloc include/linux/slab.h:493 [inline]
       tty_buffer_alloc+0xc0/0x270 drivers/tty/tty_buffer.c:169
       __tty_buffer_request_room+0x12c/0x290 drivers/tty/tty_buffer.c:267
       tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:312
       tty_insert_flip_string include/linux/tty_flip.h:37 [inline]
       pty_write+0x10d/0x1d0 drivers/tty/pty.c:122
       n_hdlc_send_frames+0x241/0x410 drivers/tty/n_hdlc.c:404
       n_hdlc_tty_write+0x4b3/0x590 drivers/tty/n_hdlc.c:714
       do_tty_write drivers/tty/tty_io.c:959 [inline]
       tty_write+0x410/0x740 drivers/tty/tty_io.c:1043
       __vfs_write+0xe4/0x630 fs/read_write.c:480
       vfs_write+0x17f/0x4d0 fs/read_write.c:544
       SYSC_write fs/read_write.c:590 [inline]
       SyS_write+0xf2/0x210 fs/read_write.c:582
       do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
       entry_SYSCALL_64_after_hwframe+0x46/0xbb

other info that might help us debug this:

Chain exists of:
  console_owner --> &port_lock_key --> &(&port->lock)->rlock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&(&port->lock)->rlock);
                               lock(&port_lock_key);
                               lock(&(&port->lock)->rlock);
  lock(console_owner);

 *** DEADLOCK ***

3 locks held by syz-executor.4/17215:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff83547072>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284
 #1:  (&tty->atomic_write_lock){+.+.}, at: [<ffffffff8352fd5d>] tty_write_lock drivers/tty/tty_io.c:885 [inline]
 #1:  (&tty->atomic_write_lock){+.+.}, at: [<ffffffff8352fd5d>] do_tty_write drivers/tty/tty_io.c:908 [inline]
 #1:  (&tty->atomic_write_lock){+.+.}, at: [<ffffffff8352fd5d>] tty_write+0x22d/0x740 drivers/tty/tty_io.c:1043
 #2:  (&(&port->lock)->rlock){-.-.}, at: [<ffffffff83552e8b>] pty_write+0xdb/0x1d0 drivers/tty/pty.c:120

stack backtrace:
CPU: 1 PID: 17215 Comm: syz-executor.4 Not tainted 4.14.228-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258
 check_prev_add kernel/locking/lockdep.c:1905 [inline]
 check_prevs_add kernel/locking/lockdep.c:2022 [inline]
 validate_chain kernel/locking/lockdep.c:2464 [inline]
 __lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491
 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
 console_trylock_spinning kernel/printk/printk.c:1679 [inline]
 vprintk_emit+0x367/0x620 kernel/printk/printk.c:1922
 vprintk_func+0x58/0x160 kernel/printk/printk_safe.c:409
 printk+0x9e/0xbc kernel/printk/printk.c:1996
 fail_dump lib/fault-inject.c:44 [inline]
 should_fail.cold+0xdf/0x149 lib/fault-inject.c:149
 should_failslab+0xd6/0x130 mm/failslab.c:32
 slab_pre_alloc_hook mm/slab.h:421 [inline]
 slab_alloc mm/slab.c:3376 [inline]
 __do_kmalloc mm/slab.c:3718 [inline]
 __kmalloc+0x6d/0x400 mm/slab.c:3729
 kmalloc include/linux/slab.h:493 [inline]
 tty_buffer_alloc+0xc0/0x270 drivers/tty/tty_buffer.c:169
 __tty_buffer_request_room+0x12c/0x290 drivers/tty/tty_buffer.c:267
 tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:312
 tty_insert_flip_string include/linux/tty_flip.h:37 [inline]
 pty_write+0x10d/0x1d0 drivers/tty/pty.c:122
 n_hdlc_send_frames+0x241/0x410 drivers/tty/n_hdlc.c:404
 n_hdlc_tty_write+0x4b3/0x590 drivers/tty/n_hdlc.c:714
 do_tty_write drivers/tty/tty_io.c:959 [inline]
 tty_write+0x410/0x740 drivers/tty/tty_io.c:1043
 __vfs_write+0xe4/0x630 fs/read_write.c:480
 vfs_write+0x17f/0x4d0 fs/read_write.c:544
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xf2/0x210 fs/read_write.c:582
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x466459
RSP: 002b:00007ff4c6da8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 00000000ffffff0b RSI: 0000000020c34fff RDI: 0000000000000003
RBP: 00007ff4c6da81d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffea9d14eaf R14: 00007ff4c6da8300 R15: 0000000000022000
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.5'.
IPVS: ftp: loaded support on port[0] = 21
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 1 PID: 17286 Comm: syz-executor.4 Not tainted 4.14.228-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 fail_dump lib/fault-inject.c:51 [inline]
 should_fail.cold+0x10a/0x149 lib/fault-inject.c:149
 should_failslab+0xd6/0x130 mm/failslab.c:32
 slab_pre_alloc_hook mm/slab.h:421 [inline]
 slab_alloc mm/slab.c:3376 [inline]
 __do_kmalloc mm/slab.c:3718 [inline]
 __kmalloc+0x6d/0x400 mm/slab.c:3729
 kmalloc include/linux/slab.h:493 [inline]
 tty_buffer_alloc+0xc0/0x270 drivers/tty/tty_buffer.c:169
 __tty_buffer_request_room+0x12c/0x290 drivers/tty/tty_buffer.c:267
 tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:312
 tty_insert_flip_string include/linux/tty_flip.h:37 [inline]
 pty_write+0x10d/0x1d0 drivers/tty/pty.c:122
 n_hdlc_send_frames+0x241/0x410 drivers/tty/n_hdlc.c:404
 n_hdlc_tty_write+0x4b3/0x590 drivers/tty/n_hdlc.c:714
 do_tty_write drivers/tty/tty_io.c:959 [inline]
 tty_write+0x410/0x740 drivers/tty/tty_io.c:1043
 __vfs_write+0xe4/0x630 fs/read_write.c:480
 vfs_write+0x17f/0x4d0 fs/read_write.c:544
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xf2/0x210 fs/read_write.c:582
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x466459
RSP: 002b:00007ff4c6da8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 00000000ffffff0b RSI: 0000000020c34fff RDI: 0000000000000003
RBP: 00007ff4c6da81d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffea9d14eaf R14: 00007ff4c6da8300 R15: 0000000000022000
BTRFS info (device loop0): disabling disk space caching
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
BTRFS info (device loop0): force zlib compression
CPU: 1 PID: 17316 Comm: syz-executor.4 Not tainted 4.14.228-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 fail_dump lib/fault-inject.c:51 [inline]
 should_fail.cold+0x10a/0x149 lib/fault-inject.c:149
BTRFS info (device loop0): turning on flush-on-commit
 should_failslab+0xd6/0x130 mm/failslab.c:32
 slab_pre_alloc_hook mm/slab.h:421 [inline]
 slab_alloc mm/slab.c:3376 [inline]
 __do_kmalloc mm/slab.c:3718 [inline]
 __kmalloc+0x6d/0x400 mm/slab.c:3729
 kmalloc include/linux/slab.h:493 [inline]
 tty_buffer_alloc+0xc0/0x270 drivers/tty/tty_buffer.c:169
BTRFS info (device loop0): has skinny extents
 __tty_buffer_request_room+0x12c/0x290 drivers/tty/tty_buffer.c:267
 tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:312
 tty_insert_flip_string include/linux/tty_flip.h:37 [inline]
 pty_write+0x10d/0x1d0 drivers/tty/pty.c:122
 n_hdlc_send_frames+0x241/0x410 drivers/tty/n_hdlc.c:404
 n_hdlc_tty_write+0x4b3/0x590 drivers/tty/n_hdlc.c:714
 do_tty_write drivers/tty/tty_io.c:959 [inline]
 tty_write+0x410/0x740 drivers/tty/tty_io.c:1043
 __vfs_write+0xe4/0x630 fs/read_write.c:480
 vfs_write+0x17f/0x4d0 fs/read_write.c:544
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xf2/0x210 fs/read_write.c:582
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x466459
RSP: 002b:00007ff4c6da8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 00000000ffffff0b RSI: 0000000020c34fff RDI: 0000000000000003
RBP: 00007ff4c6da81d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffea9d14eaf R14: 00007ff4c6da8300 R15: 0000000000022000
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 0 PID: 17374 Comm: syz-executor.4 Not tainted 4.14.228-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 fail_dump lib/fault-inject.c:51 [inline]
 should_fail.cold+0x10a/0x149 lib/fault-inject.c:149
 should_failslab+0xd6/0x130 mm/failslab.c:32
 slab_pre_alloc_hook mm/slab.h:421 [inline]
 slab_alloc mm/slab.c:3376 [inline]
 __do_kmalloc mm/slab.c:3718 [inline]
 __kmalloc+0x6d/0x400 mm/slab.c:3729
 kmalloc include/linux/slab.h:493 [inline]
 tty_buffer_alloc+0xc0/0x270 drivers/tty/tty_buffer.c:169
 __tty_buffer_request_room+0x12c/0x290 drivers/tty/tty_buffer.c:267
 tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:312
 tty_insert_flip_string include/linux/tty_flip.h:37 [inline]
 pty_write+0x10d/0x1d0 drivers/tty/pty.c:122
 n_hdlc_send_frames+0x241/0x410 drivers/tty/n_hdlc.c:404
 n_hdlc_tty_write+0x4b3/0x590 drivers/tty/n_hdlc.c:714
 do_tty_write drivers/tty/tty_io.c:959 [inline]
 tty_write+0x410/0x740 drivers/tty/tty_io.c:1043
 __vfs_write+0xe4/0x630 fs/read_write.c:480
 vfs_write+0x17f/0x4d0 fs/read_write.c:544
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xf2/0x210 fs/read_write.c:582
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x466459
RSP: 002b:00007ff4c6da8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 00000000ffffff0b RSI: 0000000020c34fff RDI: 0000000000000003
RBP: 00007ff4c6da81d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffea9d14eaf R14: 00007ff4c6da8300 R15: 0000000000022000
EXT4-fs (loop1): ext4_check_descriptors: Block bitmap for group 0 not in group (block 196608)!
EXT4-fs (loop1): group descriptors corrupted!
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 0 PID: 17404 Comm: syz-executor.4 Not tainted 4.14.228-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 fail_dump lib/fault-inject.c:51 [inline]
 should_fail.cold+0x10a/0x149 lib/fault-inject.c:149
 should_failslab+0xd6/0x130 mm/failslab.c:32
 slab_pre_alloc_hook mm/slab.h:421 [inline]
 slab_alloc mm/slab.c:3376 [inline]
 __do_kmalloc mm/slab.c:3718 [inline]
 __kmalloc+0x6d/0x400 mm/slab.c:3729
 kmalloc include/linux/slab.h:493 [inline]
 tty_buffer_alloc+0xc0/0x270 drivers/tty/tty_buffer.c:169
 __tty_buffer_request_room+0x12c/0x290 drivers/tty/tty_buffer.c:267
 tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:312
 tty_insert_flip_string include/linux/tty_flip.h:37 [inline]
 pty_write+0x10d/0x1d0 drivers/tty/pty.c:122
 n_hdlc_send_frames+0x241/0x410 drivers/tty/n_hdlc.c:404
 n_hdlc_tty_write+0x4b3/0x590 drivers/tty/n_hdlc.c:714
 do_tty_write drivers/tty/tty_io.c:959 [inline]
 tty_write+0x410/0x740 drivers/tty/tty_io.c:1043
 __vfs_write+0xe4/0x630 fs/read_write.c:480
 vfs_write+0x17f/0x4d0 fs/read_write.c:544
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xf2/0x210 fs/read_write.c:582
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x466459
RSP: 002b:00007ff4c6da8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 00000000ffffff0b RSI: 0000000020c34fff RDI: 0000000000000003
RBP: 00007ff4c6da81d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffea9d14eaf R14: 00007ff4c6da8300 R15: 0000000000022000
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 1 PID: 17426 Comm: syz-executor.4 Not tainted 4.14.228-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 fail_dump lib/fault-inject.c:51 [inline]
 should_fail.cold+0x10a/0x149 lib/fault-inject.c:149
 should_failslab+0xd6/0x130 mm/failslab.c:32
 slab_pre_alloc_hook mm/slab.h:421 [inline]
 slab_alloc mm/slab.c:3376 [inline]
 __do_kmalloc mm/slab.c:3718 [inline]
 __kmalloc+0x6d/0x400 mm/slab.c:3729
 kmalloc include/linux/slab.h:493 [inline]
 tty_buffer_alloc+0xc0/0x270 drivers/tty/tty_buffer.c:169
 __tty_buffer_request_room+0x12c/0x290 drivers/tty/tty_buffer.c:267
 tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:312
 tty_insert_flip_string include/linux/tty_flip.h:37 [inline]
 pty_write+0x10d/0x1d0 drivers/tty/pty.c:122
 n_hdlc_send_frames+0x241/0x410 drivers/tty/n_hdlc.c:404
 n_hdlc_tty_write+0x4b3/0x590 drivers/tty/n_hdlc.c:714
 do_tty_write drivers/tty/tty_io.c:959 [inline]
 tty_write+0x410/0x740 drivers/tty/tty_io.c:1043
 __vfs_write+0xe4/0x630 fs/read_write.c:480
 vfs_write+0x17f/0x4d0 fs/read_write.c:544
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xf2/0x210 fs/read_write.c:582
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x466459
RSP: 002b:00007ff4c6da8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 00000000ffffff0b RSI: 0000000020c34fff RDI: 0000000000000003
RBP: 00007ff4c6da81d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffea9d14eaf R14: 00007ff4c6da8300 R15: 0000000000022000
BTRFS info (device loop0): disabling disk space caching
BTRFS info (device loop0): force zlib compression
BTRFS info (device loop0): turning on flush-on-commit
BTRFS info (device loop0): has skinny extents
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 1 PID: 17478 Comm: syz-executor.4 Not tainted 4.14.228-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 fail_dump lib/fault-inject.c:51 [inline]
 should_fail.cold+0x10a/0x149 lib/fault-inject.c:149
 should_failslab+0xd6/0x130 mm/failslab.c:32
 slab_pre_alloc_hook mm/slab.h:421 [inline]
 slab_alloc mm/slab.c:3376 [inline]
 __do_kmalloc mm/slab.c:3718 [inline]
 __kmalloc+0x6d/0x400 mm/slab.c:3729
 kmalloc include/linux/slab.h:493 [inline]
 tty_buffer_alloc+0xc0/0x270 drivers/tty/tty_buffer.c:169
 __tty_buffer_request_room+0x12c/0x290 drivers/tty/tty_buffer.c:267
 tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:312
 tty_insert_flip_string include/linux/tty_flip.h:37 [inline]
 pty_write+0x10d/0x1d0 drivers/tty/pty.c:122
 n_hdlc_send_frames+0x241/0x410 drivers/tty/n_hdlc.c:404
 n_hdlc_tty_write+0x4b3/0x590 drivers/tty/n_hdlc.c:714
 do_tty_write drivers/tty/tty_io.c:959 [inline]
 tty_write+0x410/0x740 drivers/tty/tty_io.c:1043
 __vfs_write+0xe4/0x630 fs/read_write.c:480
 vfs_write+0x17f/0x4d0 fs/read_write.c:544
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xf2/0x210 fs/read_write.c:582
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x466459
RSP: 002b:00007ff4c6da8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 00000000ffffff0b RSI: 0000000020c34fff RDI: 0000000000000003
RBP: 00007ff4c6da81d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ffea9d14eaf R14: 00007ff4c6da8300 R15: 0000000000022000
IPVS: ftp: loaded support on port[0] = 21
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 1 PID: 17497 Comm: syz-executor.4 Not tainted 4.14.228-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 fail_dump lib/fault-inject.c:51 [inline]
 should_fail.cold+0x10a/0x149 lib/fault-inject.c:149
 should_failslab+0xd6/0x130 mm/failslab.c:32
 slab_pre_alloc_hook mm/slab.h:421 [inline]
 slab_alloc mm/slab.c:3376 [inline]
 __do_kmalloc mm/slab.c:3718 [inline]
 __kmalloc+0x6d/0x400 mm/slab.c:3729
 kmalloc include/linux/slab.h:493 [inline]
 tty_buffer_alloc+0xc0/0x270 drivers/tty/tty_buffer.c:169
 __tty_buffer_request_room+0x12c/0x290 drivers/tty/tty_buffer.c:267
 tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:312
 tty_insert_flip_string include/linux/tty_flip.h:37 [inline]
 pty_write+0x10d/0x1d0 drivers/tty/pty.c:122
 n_hdlc_send_frames+0x241/0x410 drivers/tty/n_hdlc.c:404
 n_hdlc_tty_write+0x4b3/0x590 drivers/tty/n_hdlc.c:714
 do_tty_write drivers/tty/tty_io.c:959 [inline]
 tty_write+0x410/0x740 drivers/tty/tty_io.c:1043
 __vfs_write+0xe4/0x630 fs/read_write.c:480
 vfs_write+0x17f/0x4d0 fs/read_write.c:544
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xf2/0x210 fs/read_write.c:582
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x466459
RSP: 002b:00007ff4c6da8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 00000000ffffff0b RSI: 0000000020c34fff RDI: 0000000000000003
RBP: 00007ff4c6da81d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ffea9d14eaf R14: 00007ff4c6da8300 R15: 0000000000022000
IPVS: ftp: loaded support on port[0] = 21
BTRFS info (device loop0): disabling disk space caching
BTRFS info (device loop0): force zlib compression
BTRFS info (device loop0): turning on flush-on-commit
BTRFS info (device loop0): has skinny extents
audit: type=1800 audit(1617388924.557:52): pid=17712 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.3" name="bus" dev="sda1" ino=14538 res=0
audit: type=1800 audit(1617388924.557:53): pid=17712 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.3" name="bus" dev="sda1" ino=14538 res=0
BTRFS info (device loop0): disabling disk space caching
BTRFS info (device loop0): force zlib compression
BTRFS info (device loop0): turning on flush-on-commit
BTRFS info (device loop0): has skinny extents
FAT-fs (loop3): bogus number of reserved sectors
FAT-fs (loop3): Can't find a valid FAT filesystem
FAT-fs (loop3): bogus number of reserved sectors
FAT-fs (loop3): Can't find a valid FAT filesystem
FAT-fs (loop3): bogus number of reserved sectors
FAT-fs (loop3): Can't find a valid FAT filesystem
BTRFS info (device loop0): disabling disk space caching
BTRFS info (device loop0): force zlib compression
BTRFS info (device loop0): turning on flush-on-commit
BTRFS info (device loop0): has skinny extents
FAT-fs (loop3): bogus number of reserved sectors
FAT-fs (loop3): Can't find a valid FAT filesystem
print_req_error: I/O error, dev loop3, sector 1
Buffer I/O error on dev loop3, logical block 1, async page read
print_req_error: I/O error, dev loop3, sector 2
Buffer I/O error on dev loop3, logical block 2, async page read
print_req_error: I/O error, dev loop3, sector 3
Buffer I/O error on dev loop3, logical block 3, async page read
print_req_error: I/O error, dev loop3, sector 4
Buffer I/O error on dev loop3, logical block 4, async page read
print_req_error: I/O error, dev loop3, sector 5
Buffer I/O error on dev loop3, logical block 5, async page read
print_req_error: I/O error, dev loop3, sector 6
Buffer I/O error on dev loop3, logical block 6, async page read
print_req_error: I/O error, dev loop3, sector 7
Buffer I/O error on dev loop3, logical block 7, async page read