RDX: 0000000020000100 RSI: 0000000000005412 RDI: 0000000000000006 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f642e9b36d4 R13: 00000000004c569b R14: 00000000004db588 R15: 0000000000000007 ====================================================== WARNING: possible circular locking dependency detected 4.19.87-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/14953 is trying to acquire lock: 00000000c441ce74 (console_owner){-.-.}, at: console_trylock_spinning kernel/printk/printk.c:1669 [inline] 00000000c441ce74 (console_owner){-.-.}, at: vprintk_emit+0x3d5/0x6d0 kernel/printk/printk.c:1936 but task is already holding lock: 00000000506b5da3 (&(&port->lock)->rlock){-.-.}, at: pty_write+0xff/0x200 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+0x95/0xcd kernel/locking/spinlock.c:152 tty_port_tty_get+0x22/0x90 drivers/tty/tty_port.c:288 tty_port_default_wakeup+0x16/0x40 drivers/tty/tty_port.c:47 tty_port_tty_wakeup+0x57/0x70 drivers/tty/tty_port.c:390 uart_write_wakeup+0x46/0x70 drivers/tty/serial/serial_core.c:103 serial8250_tx_chars+0x495/0xaf0 drivers/tty/serial/8250/8250_port.c:1806 serial8250_handle_irq.part.0+0x261/0x2b0 drivers/tty/serial/8250/8250_port.c:1879 serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1865 [inline] serial8250_default_handle_irq+0xc0/0x150 drivers/tty/serial/8250/8250_port.c:1895 serial8250_interrupt+0xfc/0x1e0 drivers/tty/serial/8250/8250_core.c:125 __handle_irq_event_percpu+0x144/0x8f0 kernel/irq/handle.c:149 handle_irq_event_percpu+0x74/0x160 kernel/irq/handle.c:189 handle_irq_event+0xa7/0x134 kernel/irq/handle.c:206 handle_edge_irq+0x25e/0x8d0 kernel/irq/chip.c:797 generic_handle_irq_desc include/linux/irqdesc.h:155 [inline] handle_irq+0x39/0x50 arch/x86/kernel/irq_64.c:87 do_IRQ+0x99/0x1d0 arch/x86/kernel/irq.c:246 ret_from_intr+0x0/0x1e native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:556 default_idle_call+0x36/0x90 kernel/sched/idle.c:93 cpuidle_idle_call kernel/sched/idle.c:153 [inline] do_idle+0x30c/0x4d0 kernel/sched/idle.c:263 cpu_startup_entry+0xc8/0xe0 kernel/sched/idle.c:369 rest_init+0x219/0x222 init/main.c:442 start_kernel+0x88c/0x8c5 init/main.c:738 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:490 x86_64_start_kernel+0x77/0x7b arch/x86/kernel/head64.c:471 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 -> #1 (&port_lock_key){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x95/0xcd kernel/locking/spinlock.c:152 serial8250_console_write+0x7ca/0x9f0 drivers/tty/serial/8250/8250_port.c:3247 univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:590 call_console_drivers kernel/printk/printk.c:1736 [inline] console_unlock+0xbdf/0x10d0 kernel/printk/printk.c:2429 vprintk_emit+0x280/0x6d0 kernel/printk/printk.c:1937 vprintk_default+0x28/0x30 kernel/printk/printk.c:1979 vprintk_func+0x7e/0x189 kernel/printk/printk_safe.c:398 printk+0xba/0xed kernel/printk/printk.c:2012 register_console+0x77f/0xb90 kernel/printk/printk.c:2745 univ8250_console_init+0x3e/0x4b drivers/tty/serial/8250/8250_core.c:685 console_init+0x4f7/0x761 kernel/printk/printk.c:2831 start_kernel+0x59c/0x8c5 init/main.c:661 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:490 x86_64_start_kernel+0x77/0x7b arch/x86/kernel/head64.c:471 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 -> #0 (console_owner){-.-.}: lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:3903 console_trylock_spinning kernel/printk/printk.c:1690 [inline] vprintk_emit+0x412/0x6d0 kernel/printk/printk.c:1936 vprintk_default+0x28/0x30 kernel/printk/printk.c:1979 vprintk_func+0x7e/0x189 kernel/printk/printk_safe.c:398 printk+0xba/0xed kernel/printk/printk.c:2012 fail_dump lib/fault-inject.c:44 [inline] should_fail+0x6f1/0x85c lib/fault-inject.c:149 __should_failslab+0x121/0x190 mm/failslab.c:32 should_failslab+0x9/0x14 mm/slab_common.c:1557 slab_pre_alloc_hook mm/slab.h:424 [inline] slab_alloc mm/slab.c:3383 [inline] __do_kmalloc mm/slab.c:3725 [inline] __kmalloc+0x71/0x750 mm/slab.c:3736 kmalloc include/linux/slab.h:520 [inline] tty_buffer_alloc drivers/tty/tty_buffer.c:170 [inline] __tty_buffer_request_room+0x1fb/0x5c0 drivers/tty/tty_buffer.c:268 tty_insert_flip_string_fixed_flag+0x93/0x1f0 drivers/tty/tty_buffer.c:313 tty_insert_flip_string include/linux/tty_flip.h:37 [inline] pty_write+0x133/0x200 drivers/tty/pty.c:122 tty_put_char+0x130/0x160 drivers/tty/tty_io.c:2888 do_output_char+0x15c/0x880 drivers/tty/n_tty.c:486 __process_echoes+0x3cd/0xa40 drivers/tty/n_tty.c:737 flush_echoes drivers/tty/n_tty.c:827 [inline] __receive_buf drivers/tty/n_tty.c:1646 [inline] n_tty_receive_buf_common+0xc13/0x28e0 drivers/tty/n_tty.c:1740 n_tty_receive_buf+0x31/0x40 drivers/tty/n_tty.c:1769 tiocsti drivers/tty/tty_io.c:2194 [inline] tty_ioctl+0xe91/0x1510 drivers/tty/tty_io.c:2580 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688 ksys_ioctl+0xab/0xd0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe 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 *** 4 locks held by syz-executor.2/14953: #0: 00000000ca0e60a3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000e7f517e7 (&o_tty->termios_rwsem/1){++++}, at: n_tty_receive_buf_common+0x8a/0x28e0 drivers/tty/n_tty.c:1703 #2: 00000000ff394050 (&ldata->output_lock){+.+.}, at: flush_echoes drivers/tty/n_tty.c:825 [inline] #2: 00000000ff394050 (&ldata->output_lock){+.+.}, at: __receive_buf drivers/tty/n_tty.c:1646 [inline] #2: 00000000ff394050 (&ldata->output_lock){+.+.}, at: n_tty_receive_buf_common+0xbd6/0x28e0 drivers/tty/n_tty.c:1740 #3: 00000000506b5da3 (&(&port->lock)->rlock){-.-.}, at: pty_write+0xff/0x200 drivers/tty/pty.c:120 stack backtrace: CPU: 1 PID: 14953 Comm: syz-executor.2 Not tainted 4.19.87-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_circular_bug.isra.0.cold+0x1cc/0x28f kernel/locking/lockdep.c:1221 check_prev_add kernel/locking/lockdep.c:1861 [inline] check_prevs_add kernel/locking/lockdep.c:1974 [inline] validate_chain kernel/locking/lockdep.c:2415 [inline] __lock_acquire+0x2e19/0x49c0 kernel/locking/lockdep.c:3411 lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:3903 console_trylock_spinning kernel/printk/printk.c:1690 [inline] vprintk_emit+0x412/0x6d0 kernel/printk/printk.c:1936 vprintk_default+0x28/0x30 kernel/printk/printk.c:1979 vprintk_func+0x7e/0x189 kernel/printk/printk_safe.c:398 printk+0xba/0xed kernel/printk/printk.c:2012 fail_dump lib/fault-inject.c:44 [inline] should_fail+0x6f1/0x85c lib/fault-inject.c:149 __should_failslab+0x121/0x190 mm/failslab.c:32 should_failslab+0x9/0x14 mm/slab_common.c:1557 slab_pre_alloc_hook mm/slab.h:424 [inline] slab_alloc mm/slab.c:3383 [inline] __do_kmalloc mm/slab.c:3725 [inline] __kmalloc+0x71/0x750 mm/slab.c:3736 kmalloc include/linux/slab.h:520 [inline] tty_buffer_alloc drivers/tty/tty_buffer.c:170 [inline] __tty_buffer_request_room+0x1fb/0x5c0 drivers/tty/tty_buffer.c:268 tty_insert_flip_string_fixed_flag+0x93/0x1f0 drivers/tty/tty_buffer.c:313 tty_insert_flip_string include/linux/tty_flip.h:37 [inline] pty_write+0x133/0x200 drivers/tty/pty.c:122 tty_put_char+0x130/0x160 drivers/tty/tty_io.c:2888 do_output_char+0x15c/0x880 drivers/tty/n_tty.c:486 __process_echoes+0x3cd/0xa40 drivers/tty/n_tty.c:737 flush_echoes drivers/tty/n_tty.c:827 [inline] __receive_buf drivers/tty/n_tty.c:1646 [inline] n_tty_receive_buf_common+0xc13/0x28e0 drivers/tty/n_tty.c:1740 n_tty_receive_buf+0x31/0x40 drivers/tty/n_tty.c:1769 tiocsti drivers/tty/tty_io.c:2194 [inline] tty_ioctl+0xe91/0x1510 drivers/tty/tty_io.c:2580 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688 ksys_ioctl+0xab/0xd0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a679 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f642e9b2c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f642e9b2c90 RCX: 000000000045a679 RDX: 0000000020000100 RSI: 0000000000005412 RDI: 0000000000000006 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f642e9b36d4 R13: 00000000004c569b R14: 00000000004db588 R15: 0000000000000007 kobject: 'loop3' (00000000fe0fce78): kobject_uevent_env kobject: '0:45' (000000009ee24272): kobject_add_internal: parent: 'bdi', set: 'devices' kobject: 'loop3' (00000000fe0fce78): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: '0:45' (000000009ee24272): kobject_uevent_env kobject: '0:45' (000000009ee24272): fill_kobj_path: path = '/devices/virtual/bdi/0:45' kobject: 'loop5' (00000000c15c5d15): kobject_uevent_env kobject: 'loop5' (00000000c15c5d15): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop2' (00000000678e9f0f): kobject_uevent_env kobject: 'loop2' (00000000678e9f0f): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: '0:45' (000000009ee24272): kobject_uevent_env kobject: '0:45' (000000009ee24272): fill_kobj_path: path = '/devices/virtual/bdi/0:45' kobject: '0:45' (000000009ee24272): kobject_cleanup, parent (null) kobject: '0:45' (000000009ee24272): calling ktype release kobject: '0:45': free name kobject: '0:44' (000000008696558f): kobject_uevent_env kobject: '0:44' (000000008696558f): fill_kobj_path: path = '/devices/virtual/bdi/0:44' kobject: '0:44' (000000008696558f): kobject_cleanup, parent (null) kobject: '0:44' (000000008696558f): calling ktype release kobject: '0:44': free name kobject: 'loop0' (0000000025113663): kobject_uevent_env kobject: 'loop0' (0000000025113663): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop1' (00000000c14b9382): kobject_uevent_env FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 kobject: 'loop1' (00000000c14b9382): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: '0:44' (00000000f5471996): kobject_add_internal: parent: 'bdi', set: 'devices' kobject: 'loop4' (00000000dacf2519): kobject_uevent_env kobject: 'loop4' (00000000dacf2519): fill_kobj_path: path = '/devices/virtual/block/loop4' CPU: 1 PID: 14975 Comm: syz-executor.3 Not tainted 4.19.87-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0xa/0x1b lib/fault-inject.c:149 __should_failslab+0x121/0x190 mm/failslab.c:32 should_failslab+0x9/0x14 mm/slab_common.c:1557 kobject: '0:44' (00000000f5471996): kobject_uevent_env slab_pre_alloc_hook mm/slab.h:424 [inline] slab_alloc_node mm/slab.c:3304 [inline] kmem_cache_alloc_node_trace+0x274/0x720 mm/slab.c:3666 kobject: 'loop5' (00000000c15c5d15): kobject_uevent_env __do_kmalloc_node mm/slab.c:3688 [inline] __kmalloc_node_track_caller+0x3d/0x80 mm/slab.c:3703 __kmalloc_reserve.isra.0+0x40/0xf0 net/core/skbuff.c:137 kobject: 'loop5' (00000000c15c5d15): fill_kobj_path: path = '/devices/virtual/block/loop5' __alloc_skb+0x10b/0x5f0 net/core/skbuff.c:205 kobject: 'loop4' (00000000dacf2519): kobject_uevent_env kobject: '0:44' (00000000f5471996): fill_kobj_path: path = '/devices/virtual/bdi/0:44' kobject: 'loop4' (00000000dacf2519): fill_kobj_path: path = '/devices/virtual/block/loop4' alloc_skb include/linux/skbuff.h:995 [inline] alloc_skb_with_frags+0x93/0x590 net/core/skbuff.c:5303 sock_alloc_send_pskb+0x72d/0x8a0 net/core/sock.c:2085 sock_alloc_send_skb+0x32/0x40 net/core/sock.c:2102 __ip_append_data.isra.0+0x13a7/0x2620 net/ipv4/ip_output.c:982 kobject: 'loop4' (00000000dacf2519): kobject_uevent_env kobject: 'loop4' (00000000dacf2519): fill_kobj_path: path = '/devices/virtual/block/loop4' ip_make_skb+0x249/0x2c0 net/ipv4/ip_output.c:1508 udp_sendmsg+0x1db7/0x25e0 net/ipv4/udp.c:1127 kobject: '0:45' (00000000b0b3cbf1): kobject_add_internal: parent: 'bdi', set: 'devices' udpv6_sendmsg+0x1498/0x2a00 net/ipv6/udp.c:1221 kobject: 'loop4' (00000000dacf2519): kobject_uevent_env kobject: '0:45' (00000000b0b3cbf1): kobject_uevent_env kobject: 'loop4' (00000000dacf2519): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: '0:45' (00000000b0b3cbf1): fill_kobj_path: path = '/devices/virtual/bdi/0:45' inet_sendmsg+0x141/0x5d0 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:632 ___sys_sendmsg+0x3e2/0x920 net/socket.c:2115 __sys_sendmmsg+0x1bf/0x4e0 net/socket.c:2210 __do_sys_sendmmsg net/socket.c:2239 [inline] __se_sys_sendmmsg net/socket.c:2236 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2236 kobject: 'loop4' (00000000dacf2519): kobject_uevent_env do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe kobject: 'loop4' (00000000dacf2519): fill_kobj_path: path = '/devices/virtual/block/loop4' RIP: 0033:0x45a679 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f5d1e27ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f5d1e27ec90 RCX: 000000000045a679 RDX: 03fffffffffffdeb RSI: 0000000020000380 RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5d1e27f6d4 R13: 00000000004c8da8 R14: 00000000004e0688 R15: 0000000000000005 kobject: 'loop2' (00000000678e9f0f): kobject_uevent_env kobject: 'loop2' (00000000678e9f0f): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop3' (00000000fe0fce78): kobject_uevent_env kobject: '0:45' (00000000b0b3cbf1): kobject_uevent_env kobject: 'loop3' (00000000fe0fce78): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: '0:45' (00000000b0b3cbf1): fill_kobj_path: path = '/devices/virtual/bdi/0:45' kobject: 'loop5' (00000000c15c5d15): kobject_uevent_env kobject: 'loop5' (00000000c15c5d15): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: '0:45' (00000000b0b3cbf1): kobject_cleanup, parent (null) kobject: '0:45' (00000000b0b3cbf1): calling ktype release kobject: '0:45': free name kobject: '0:44' (00000000f5471996): kobject_uevent_env kobject: '0:44' (00000000f5471996): fill_kobj_path: path = '/devices/virtual/bdi/0:44' kobject: '0:44' (00000000f5471996): kobject_cleanup, parent (null) kobject: '0:44' (00000000f5471996): calling ktype release kobject: '0:44': free name kobject: 'loop0' (0000000025113663): kobject_uevent_env kobject: 'loop0' (0000000025113663): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: '0:44' (0000000077fbbaed): kobject_add_internal: parent: 'bdi', set: 'devices' kobject: '0:44' (0000000077fbbaed): kobject_uevent_env kobject: '0:44' (0000000077fbbaed): fill_kobj_path: path = '/devices/virtual/bdi/0:44' kobject: '0:45' (0000000033f3a3df): kobject_add_internal: parent: 'bdi', set: 'devices' kobject: '0:45' (0000000033f3a3df): kobject_uevent_env kobject: '0:45' (0000000033f3a3df): fill_kobj_path: path = '/devices/virtual/bdi/0:45' kobject: '0:45' (0000000033f3a3df): kobject_uevent_env kobject: '0:45' (0000000033f3a3df): fill_kobj_path: path = '/devices/virtual/bdi/0:45' kobject: '0:45' (0000000033f3a3df): kobject_cleanup, parent (null) kobject: '0:45' (0000000033f3a3df): calling ktype release kobject: '0:45': free name kobject: '0:44' (0000000077fbbaed): kobject_uevent_env kobject: '0:44' (0000000077fbbaed): fill_kobj_path: path = '/devices/virtual/bdi/0:44' kobject: '0:44' (0000000077fbbaed): kobject_cleanup, parent (null) kobject: '0:44' (0000000077fbbaed): calling ktype release kobject: '0:44': free name kobject: 'loop0' (0000000025113663): kobject_uevent_env kobject: 'loop0' (0000000025113663): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop1' (00000000c14b9382): kobject_uevent_env kobject: '0:44' (0000000050deffa9): kobject_add_internal: parent: 'bdi', set: 'devices' kobject: 'loop1' (00000000c14b9382): fill_kobj_path: path = '/devices/virtual/block/loop1' FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 kobject: '0:44' (0000000050deffa9): kobject_uevent_env kobject: '0:44' (0000000050deffa9): fill_kobj_path: path = '/devices/virtual/bdi/0:44' kobject: 'loop4' (00000000dacf2519): kobject_uevent_env kobject: 'loop4' (00000000dacf2519): fill_kobj_path: path = '/devices/virtual/block/loop4' CPU: 0 PID: 15027 Comm: syz-executor.3 Not tainted 4.19.87-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 kobject: 'loop2' (00000000678e9f0f): kobject_uevent_env Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0xa/0x1b lib/fault-inject.c:149 __should_failslab+0x121/0x190 mm/failslab.c:32 should_failslab+0x9/0x14 mm/slab_common.c:1557 slab_pre_alloc_hook mm/slab.h:424 [inline] slab_alloc mm/slab.c:3383 [inline] kmem_cache_alloc+0x47/0x700 mm/slab.c:3557 skb_clone+0x156/0x3e0 net/core/skbuff.c:1284 ip_mc_output+0x3b0/0xf50 net/ipv4/ip_output.c:367 kobject: 'loop2' (00000000678e9f0f): fill_kobj_path: path = '/devices/virtual/block/loop2' dst_output include/net/dst.h:447 [inline] ip_local_out+0xbb/0x190 net/ipv4/ip_output.c:124 kobject: 'loop5' (00000000c15c5d15): kobject_uevent_env ip_send_skb+0x42/0xf0 net/ipv4/ip_output.c:1442 udp_send_skb.isra.0+0x6de/0x1200 net/ipv4/udp.c:845 kobject: 'loop5' (00000000c15c5d15): fill_kobj_path: path = '/devices/virtual/block/loop5' udp_sendmsg+0x1e04/0x25e0 net/ipv4/udp.c:1132 kobject: 'loop4' (00000000dacf2519): kobject_uevent_env kobject: 'loop4' (00000000dacf2519): fill_kobj_path: path = '/devices/virtual/block/loop4' udpv6_sendmsg+0x1498/0x2a00 net/ipv6/udp.c:1221 inet_sendmsg+0x141/0x5d0 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:632 ___sys_sendmsg+0x3e2/0x920 net/socket.c:2115 kobject: 'loop4' (00000000dacf2519): kobject_uevent_env __sys_sendmmsg+0x1bf/0x4e0 net/socket.c:2210 kobject: 'loop4' (00000000dacf2519): fill_kobj_path: path = '/devices/virtual/block/loop4' __do_sys_sendmmsg net/socket.c:2239 [inline] __se_sys_sendmmsg net/socket.c:2236 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2236 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a679 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f5d1e27ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f5d1e27ec90 RCX: 000000000045a679 RDX: 03fffffffffffdeb RSI: 0000000020000380 RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5d1e27f6d4 kobject: 'loop4' (00000000dacf2519): kobject_uevent_env R13: 00000000004c8da8 R14: 00000000004e0688 R15: 0000000000000005 kobject: 'loop4' (00000000dacf2519): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: '0:44' (0000000050deffa9): kobject_uevent_env kobject: 'loop5' (00000000c15c5d15): kobject_uevent_env kobject: 'loop5' (00000000c15c5d15): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: '0:44' (0000000050deffa9): fill_kobj_path: path = '/devices/virtual/bdi/0:44' kobject: '0:44' (0000000050deffa9): kobject_cleanup, parent (null) kobject: '0:44' (0000000050deffa9): calling ktype release kobject: '0:44': free name kobject: 'loop0' (0000000025113663): kobject_uevent_env kobject: 'loop0' (0000000025113663): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop3' (00000000fe0fce78): kobject_uevent_env kobject: 'loop3' (00000000fe0fce78): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop1' (00000000c14b9382): kobject_uevent_env FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 kobject: 'loop1' (00000000c14b9382): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: '0:44' (00000000acabf567): kobject_add_internal: parent: 'bdi', set: 'devices' CPU: 1 PID: 15067 Comm: syz-executor.3 Not tainted 4.19.87-syzkaller #0 kobject: '0:44' (00000000acabf567): kobject_uevent_env Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0xa/0x1b lib/fault-inject.c:149 kobject: '0:44' (00000000acabf567): fill_kobj_path: path = '/devices/virtual/bdi/0:44' __should_failslab+0x121/0x190 mm/failslab.c:32 should_failslab+0x9/0x14 mm/slab_common.c:1557 slab_pre_alloc_hook mm/slab.h:424 [inline] slab_alloc mm/slab.c:3383 [inline] kmem_cache_alloc+0x47/0x700 mm/slab.c:3557 kobject: 'loop2' (00000000678e9f0f): kobject_uevent_env dst_alloc+0x10e/0x1d0 net/core/dst.c:105 rt_dst_alloc+0x83/0x3f0 net/ipv4/route.c:1613 kobject: 'loop2' (00000000678e9f0f): fill_kobj_path: path = '/devices/virtual/block/loop2' __mkroute_output net/ipv4/route.c:2313 [inline] ip_route_output_key_hash_rcu+0x97d/0x30e0 net/ipv4/route.c:2543 ip_route_output_key_hash+0x212/0x380 net/ipv4/route.c:2369 __ip_route_output_key include/net/route.h:124 [inline] ip_route_output_flow+0x28/0xc0 net/ipv4/route.c:2627 udp_sendmsg+0x1adb/0x25e0 net/ipv4/udp.c:1098 kobject: 'loop2' (00000000678e9f0f): kobject_uevent_env kobject: 'loop2' (00000000678e9f0f): fill_kobj_path: path = '/devices/virtual/block/loop2' udpv6_sendmsg+0x1498/0x2a00 net/ipv6/udp.c:1221 kobject: 'loop2' (00000000678e9f0f): kobject_uevent_env kobject: 'loop2' (00000000678e9f0f): fill_kobj_path: path = '/devices/virtual/block/loop2' inet_sendmsg+0x141/0x5d0 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:632 ___sys_sendmsg+0x3e2/0x920 net/socket.c:2115 __sys_sendmmsg+0x1bf/0x4e0 net/socket.c:2210 kobject: 'loop2' (00000000678e9f0f): kobject_uevent_env kobject: 'loop2' (00000000678e9f0f): fill_kobj_path: path = '/devices/virtual/block/loop2' __do_sys_sendmmsg net/socket.c:2239 [inline] __se_sys_sendmmsg net/socket.c:2236 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2236 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a679 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f5d1e27ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f5d1e27ec90 RCX: 000000000045a679 RDX: 03fffffffffffdeb RSI: 0000000020000380 RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5d1e27f6d4 R13: 00000000004c8da8 R14: 00000000004e0688 R15: 0000000000000005 kobject: 'loop4' (00000000dacf2519): kobject_uevent_env kobject: 'loop4' (00000000dacf2519): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop3' (00000000fe0fce78): kobject_uevent_env kobject: 'loop3' (00000000fe0fce78): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop5' (00000000c15c5d15): kobject_uevent_env kobject: 'loop5' (00000000c15c5d15): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: '0:45' (000000005bd39e81): kobject_add_internal: parent: 'bdi', set: 'devices' kobject: '0:45' (000000005bd39e81): kobject_uevent_env kobject: '0:45' (000000005bd39e81): fill_kobj_path: path = '/devices/virtual/bdi/0:45' kobject: '0:45' (000000005bd39e81): kobject_uevent_env kobject: '0:45' (000000005bd39e81): fill_kobj_path: path = '/devices/virtual/bdi/0:45' kobject: '0:45' (000000005bd39e81): kobject_cleanup, parent (null) kobject: '0:45' (000000005bd39e81): calling ktype release kobject: '0:45': free name kobject: '0:44' (00000000acabf567): kobject_uevent_env kobject: '0:44' (00000000acabf567): fill_kobj_path: path = '/devices/virtual/bdi/0:44' kobject: '0:44' (00000000acabf567): kobject_cleanup, parent (null) kobject: '0:44' (00000000acabf567): calling ktype release kobject: '0:44': free name kobject: 'loop0' (0000000025113663): kobject_uevent_env kobject: 'loop0' (0000000025113663): fill_kobj_path: path = '/devices/virtual/block/loop0'