RDX: 0000000000000090 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007f191ee8e1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffda3ac74bf R14: 00007f191ee8e300 R15: 0000000000022000 ====================================================== WARNING: possible circular locking dependency detected 4.14.290-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/21712 is trying to acquire lock: CPU: 0 PID: 21710 Comm: syz-executor.5 Not tainted 4.14.290-syzkaller #0 (console_owner){....}, at: [] console_trylock_spinning kernel/printk/printk.c:1660 [inline] (console_owner){....}, at: [] vprintk_emit+0x32a/0x620 kernel/printk/printk.c:1924 but task is already holding lock: (&(&port->lock)->rlock){-.-.}, at: [] tty_insert_flip_string_and_push_buffer+0x2b/0x160 drivers/tty/tty_buffer.c:569 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/0xc70 drivers/tty/serial/8250/8250_port.c:1828 serial8250_handle_irq.part.0+0x28d/0x330 drivers/tty/serial/8250/8250_port.c:1915 serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1888 [inline] serial8250_default_handle_irq+0x8a/0x1f0 drivers/tty/serial/8250/8250_port.c:1931 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+0xed/0x240 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_kernel+0x743/0x763 init/main.c:712 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+0x7d5/0xa10 drivers/tty/serial/8250/8250_port.c:3273 call_console_drivers kernel/printk/printk.c:1727 [inline] console_unlock+0x99d/0xf20 kernel/printk/printk.c:2409 vprintk_emit+0x224/0x620 kernel/printk/printk.c:1925 vprintk_func+0x58/0x160 kernel/printk/printk_safe.c:409 printk+0x9e/0xbc kernel/printk/printk.c:1998 register_console+0x6f4/0xad0 kernel/printk/printk.c:2728 univ8250_console_init+0x2f/0x3a drivers/tty/serial/8250/8250_core.c:691 console_init+0x46/0x53 kernel/printk/printk.c:2809 start_kernel+0x521/0x763 init/main.c:638 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:1681 [inline] vprintk_emit+0x367/0x620 kernel/printk/printk.c:1924 vprintk_func+0x58/0x160 kernel/printk/printk_safe.c:409 printk+0x9e/0xbc kernel/printk/printk.c:1998 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:268 tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:313 tty_insert_flip_string include/linux/tty_flip.h:36 [inline] tty_insert_flip_string_and_push_buffer+0x3e/0x160 drivers/tty/tty_buffer.c:570 pty_write+0xc3/0xf0 drivers/tty/pty.c:118 n_tty_write+0x85e/0xda0 drivers/tty/n_tty.c:2356 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 *** 5 locks held by syz-executor.2/21712: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&tty->atomic_write_lock){+.+.}, at: [] tty_write_lock drivers/tty/tty_io.c:885 [inline] #1: (&tty->atomic_write_lock){+.+.}, at: [] do_tty_write drivers/tty/tty_io.c:908 [inline] #1: (&tty->atomic_write_lock){+.+.}, at: [] tty_write+0x22d/0x740 drivers/tty/tty_io.c:1043 #2: (&tty->termios_rwsem){++++}, at: [] n_tty_write+0x18a/0xda0 drivers/tty/n_tty.c:2316 #3: (&ldata->output_lock){+.+.}, at: [] n_tty_write+0x82b/0xda0 drivers/tty/n_tty.c:2355 #4: (&(&port->lock)->rlock){-.-.}, at: [] tty_insert_flip_string_and_push_buffer+0x2b/0x160 drivers/tty/tty_buffer.c:569 stack backtrace: CPU: 1 PID: 21712 Comm: syz-executor.2 Not tainted 4.14.290-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 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:1681 [inline] vprintk_emit+0x367/0x620 kernel/printk/printk.c:1924 vprintk_func+0x58/0x160 kernel/printk/printk_safe.c:409 printk+0x9e/0xbc kernel/printk/printk.c:1998 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:268 tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:313 tty_insert_flip_string include/linux/tty_flip.h:36 [inline] tty_insert_flip_string_and_push_buffer+0x3e/0x160 drivers/tty/tty_buffer.c:570 pty_write+0xc3/0xf0 drivers/tty/pty.c:118 n_tty_write+0x85e/0xda0 drivers/tty/n_tty.c:2356 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: 0033:0x7f1920519279 RSP: 002b:00007f191ee8e168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f192062bf80 RCX: 00007f1920519279 RDX: 0000000000000090 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007f191ee8e1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffda3ac74bf R14: 00007f191ee8e300 R15: 0000000000022000 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 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] kmem_cache_alloc+0x28e/0x3c0 mm/slab.c:3550 ext4_alloc_inode+0x1a/0x640 fs/ext4/super.c:1013 alloc_inode+0x5d/0x170 fs/inode.c:210 new_inode_pseudo fs/inode.c:899 [inline] new_inode+0x1d/0xf0 fs/inode.c:928 __ext4_new_inode+0x360/0x4eb0 fs/ext4/ialloc.c:839 ext4_mknod+0x248/0x520 fs/ext4/namei.c:2555 vfs_mknod+0x40b/0x680 fs/namei.c:3757 SYSC_mknodat fs/namei.c:3813 [inline] SyS_mknodat+0x230/0x470 fs/namei.c:3781 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7ff84851b279 RSP: 002b:00007ff846e90168 EFLAGS: 00000246 ORIG_RAX: 0000000000000103 RAX: ffffffffffffffda RBX: 00007ff84862df80 RCX: 00007ff84851b279 RDX: 0000000000001000 RSI: 0000000020000100 RDI: ffffffffffffff9c RBP: 00007ff846e901d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000103 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffe24b20a3f R14: 00007ff846e90300 R15: 0000000000022000 CPU: 1 PID: 21707 Comm: syz-executor.4 Not tainted 4.14.290-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 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] kmem_cache_alloc+0x28e/0x3c0 mm/slab.c:3550 kmem_cache_zalloc include/linux/slab.h:651 [inline] get_empty_filp+0x86/0x3f0 fs/file_table.c:123 path_openat+0x84/0x2970 fs/namei.c:3545 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f0956168279 RSP: 002b:00007f0954add168 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f095627af80 RCX: 00007f0956168279 RDX: 0000000000004000 RSI: 00000000200000c0 RDI: ffffffffffffff9c RBP: 00007f0954add1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff3e43c23f R14: 00007f0954add300 R15: 0000000000022000 FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): Unrecognized mount option "allowutime=0002" or missing value FAT-fs (loop1): Unrecognized mount option "allowutime=0002" or missing value FAT-fs (loop1): Unrecognized mount option "allowutime=0002" or missing value print_req_error: I/O error, dev loop5, sector 0 cramfs: wrong magic FAT-fs (loop1): bogus number of reserved sectors print_req_error: I/O error, dev loop5, sector 0 FAT-fs (loop1): Can't find a valid FAT filesystem cramfs: wrong magic print_req_error: I/O error, dev loop1, sector 0 print_req_error: I/O error, dev loop2, sector 0 print_req_error: I/O error, dev loop5, sector 0 cramfs: wrong magic FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem print_req_error: I/O error, dev loop1, sector 0 FAT-fs (loop1): Unrecognized mount option "fsuuid=fle58efa-b134-edb0-8adf-28547a0e" or missing value FAT-fs (loop1): Unrecognized mount option "fsuuid=fle58efa-b134-edb0-8adf-28547a0e" or missing value FAT-fs (loop1): Unrecognized mount option "fsuuid=fle58efa-b134-edb0-8adf-28547a0e" or missing value FAT-fs (loop1): Unrecognized mount option "allow000" or missing value FAT-fs (loop1): Unrecognized mount option "allow000" or missing value FAT-fs (loop1): Unrecognized mount option "allow000" or missing value FAT-fs (loop1): Unrecognized mount option "allow000" or missing value FAT-fs (loop1): bogus number of reserved sectors netlink: 8 bytes leftover after parsing attributes in process `syz-executor.0'. FAT-fs (loop1): Can't find a valid FAT filesystem netlink: 8 bytes leftover after parsing attributes in process `syz-executor.0'. FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): 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 cramfs: wrong magic FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): 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 cramfs: wrong magic FAT-fs (loop1): bogus number of reserved sectors print_req_error: I/O error, dev loop2, sector 8 FAT-fs (loop1): 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 cramfs: wrong magic FAT-fs (loop3): bogus number of reserved sectors FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop3): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): 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 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.1'. FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): 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 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.1'. FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): 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 (loop1): bogus number of reserved sectors FAT-fs (loop1): 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 print_req_error: I/O error, dev loop2, sector 0 FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem print_req_error: I/O error, dev loop5, sector 0 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.1'. FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): 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 (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop1): bogus number of reserved sectors FAT-fs (loop3): bogus number of reserved sectors FAT-fs (loop1): Can't find a valid FAT filesystem FAT-fs (loop3): Can't find a valid FAT filesystem cramfs: wrong magic FAT-fs (loop3): bogus number of reserved sectors FAT-fs (loop1): bogus number of reserved sectors cramfs: wrong magic FAT-fs (loop3): Can't find a valid FAT filesystem FAT-fs (loop1): Can't find a valid FAT filesystem