RBP: 00007fce95297ca0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007ffdeaf344bf R14: 00007fce952989c0 R15: 000000000119bf8c CPU: 1 PID: 15494 Comm: syz-executor.5 Not tainted 4.14.214-syzkaller #0 ====================================================== WARNING: possible circular locking dependency detected 4.14.214-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/15490 is trying to acquire lock: (console_owner){-.-.}, at: [] console_trylock_spinning kernel/printk/printk.c:1658 [inline] (console_owner){-.-.}, at: [] vprintk_emit+0x32a/0x620 kernel/printk/printk.c:1922 but task is already holding lock: (&(&port->lock)->rlock){-.-.}, at: [] 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+0xf0/0x246 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+0x750/0x770 init/main.c:708 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+0x58/0x152 kernel/printk/printk_safe.c:401 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+0x58/0x152 kernel/printk/printk_safe.c:401 printk+0x9e/0xbc kernel/printk/printk.c:1996 fail_dump lib/fault-inject.c:44 [inline] should_fail.cold+0xdf/0x154 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_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.0/15490: #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: [] pty_write+0xdb/0x1d0 drivers/tty/pty.c:120 stack backtrace: CPU: 0 PID: 15490 Comm: syz-executor.0 Not tainted 4.14.214-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+0x1b2/0x283 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+0x58/0x152 kernel/printk/printk_safe.c:401 printk+0x9e/0xbc kernel/printk/printk.c:1996 fail_dump lib/fault-inject.c:44 [inline] should_fail.cold+0xdf/0x154 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_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: 0033:0x45e219 RSP: 002b:00007fce95297c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e219 RDX: 00000000ffffff0b RSI: 0000000020c34fff RDI: 0000000000000004 RBP: 00007fce95297ca0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007ffdeaf344bf R14: 00007fce952989c0 R15: 000000000119bf8c 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+0x1b2/0x283 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10a/0x154 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] __kernfs_new_node+0x6f/0x470 fs/kernfs/dir.c:632 kernfs_new_node+0x7b/0xe0 fs/kernfs/dir.c:677 __kernfs_create_file+0x3d/0x320 fs/kernfs/file.c:989 sysfs_add_file_mode_ns+0x1e1/0x450 fs/sysfs/file.c:307 create_files fs/sysfs/group.c:64 [inline] internal_create_group+0x22b/0x710 fs/sysfs/group.c:134 sysfs_create_group fs/sysfs/group.c:156 [inline] sysfs_create_groups fs/sysfs/group.c:183 [inline] sysfs_create_groups+0x92/0x127 fs/sysfs/group.c:173 device_add_groups drivers/base/core.c:1049 [inline] device_add_attrs drivers/base/core.c:1197 [inline] device_add+0x7e5/0x15c0 drivers/base/core.c:1886 netdev_register_kobject+0x181/0x410 net/core/net-sysfs.c:1608 register_netdevice+0x955/0xe40 net/core/dev.c:7660 macvlan_common_newlink+0xb5a/0x1480 drivers/net/macvlan.c:1436 macvtap_newlink drivers/net/macvtap.c:108 [inline] macvtap_newlink+0x17b/0x230 drivers/net/macvtap.c:80 rtnl_newlink+0xf88/0x1830 net/core/rtnetlink.c:2728 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4316 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2433 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x62e/0xb80 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 ___sys_sendmsg+0x6c8/0x800 net/socket.c:2062 __sys_sendmsg+0xa3/0x120 net/socket.c:2096 SYSC_sendmsg net/socket.c:2107 [inline] SyS_sendmsg+0x27/0x40 net/socket.c:2103 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45e219 RSP: 002b:00007fa45c3ecc68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 000000000045e219 RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000006 RBP: 00007fa45c3ecca0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000001f R13: 00007ffeae0b53af R14: 00007fa45c3ed9c0 R15: 000000000119bf8c netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. ldm_validate_privheads(): Disk read failed. loop5: p2 < > netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. loop5: p2 size 2 extends beyond EOD, truncated netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated nla_parse: 3 callbacks suppressed netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. ldm_validate_privheads(): Disk read failed. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated netlink: 8 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.1'. ldm_validate_privheads(): Disk read failed. loop5: p2 < > netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'. ldm_validate_privheads(): Disk read failed. loop5: p2 < > loop5: partition table partially beyond EOD, truncated loop5: p2 size 2 extends beyond EOD, truncated