syzbot has found a reproducer for the following issue on: HEAD commit: 7c8ca812 Add linux-next specific files for 20201117 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=16576c0e500000 kernel config: https://syzkaller.appspot.com/x/.config?x=ff4bc71371dc5b13 dashboard link: https://syzkaller.appspot.com/bug?extid=3e12e14ee01b675e1af2 compiler: gcc (GCC) 10.1.0-syz 20200507 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14b1dba6500000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12de8636500000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+3e12e14ee01b675e1af2@xxxxxxxxxxxxxxxxxxxxxxxxx netdevsim netdevsim0 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim0 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0 ======================================================== WARNING: possible irq lock inversion dependency detected 5.10.0-rc4-next-20201117-syzkaller #0 Not tainted -------------------------------------------------------- syz-executor335/8500 just changed the state of lock: ffff888012a010c0 (&new->fa_lock){.+..}-{2:2}, at: kill_fasync_rcu fs/fcntl.c:1004 [inline] ffff888012a010c0 (&new->fa_lock){.+..}-{2:2}, at: kill_fasync fs/fcntl.c:1025 [inline] ffff888012a010c0 (&new->fa_lock){.+..}-{2:2}, at: kill_fasync+0x14b/0x460 fs/fcntl.c:1018 but this lock was taken by another, HARDIRQ-safe lock in the past: (&dev->event_lock){-...}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Chain exists of: &dev->event_lock --> &client->buffer_lock --> &new->fa_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&new->fa_lock); local_irq_disable(); lock(&dev->event_lock); lock(&client->buffer_lock); <Interrupt> lock(&dev->event_lock); *** DEADLOCK *** 3 locks held by syz-executor335/8500: #0: ffffffff8b339ca0 (rcu_read_lock){....}-{1:2}, at: sock_def_error_report+0x0/0x4c0 include/net/sock.h:2263 #1: ffffffff8b339ca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_release include/linux/rcupdate.h:260 [inline] #1: ffffffff8b339ca0 (rcu_read_lock){....}-{1:2}, at: rcu_read_unlock include/linux/rcupdate.h:698 [inline] #1: ffffffff8b339ca0 (rcu_read_lock){....}-{1:2}, at: sock_def_error_report+0x1cc/0x4c0 net/core/sock.c:2879 #2: ffffffff8b339ca0 (rcu_read_lock){....}-{1:2}, at: kill_fasync+0x3d/0x460 fs/fcntl.c:1023 the shortest dependencies between 2nd lock and 1st lock: -> (&dev->event_lock){-...}-{2:2} { IN-HARDIRQ-W at: lock_acquire kernel/locking/lockdep.c:5435 [inline] lock_acquire+0x2a3/0x8c0 kernel/locking/lockdep.c:5400 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:159 input_event drivers/input/input.c:440 [inline] input_event+0x7b/0xb0 drivers/input/input.c:433 input_report_key include/linux/input.h:417 [inline] psmouse_report_standard_buttons+0x2c/0x80 drivers/input/mouse/psmouse-base.c:123 psmouse_report_standard_packet drivers/input/mouse/psmouse-base.c:141 [inline] psmouse_process_byte+0x1e1/0x890 drivers/input/mouse/psmouse-base.c:232 psmouse_handle_byte+0x41/0x1b0 drivers/input/mouse/psmouse-base.c:274 psmouse_interrupt+0x304/0xf00 drivers/input/mouse/psmouse-base.c:426 serio_interrupt+0x88/0x150 drivers/input/serio/serio.c:1002 i8042_interrupt+0x27a/0x520 drivers/input/serio/i8042.c:602 __handle_irq_event_percpu+0x303/0x8f0 kernel/irq/handle.c:156 handle_irq_event_percpu kernel/irq/handle.c:196 [inline] handle_irq_event+0x102/0x290 kernel/irq/handle.c:213 handle_edge_irq+0x25f/0xd00 kernel/irq/chip.c:819 asm_call_irq_on_stack+0xf/0x20 __run_irq_on_irqstack arch/x86/include/asm/irq_stack.h:48 [inline] run_irq_on_irqstack_cond arch/x86/include/asm/irq_stack.h:101 [inline] handle_irq arch/x86/kernel/irq.c:230 [inline] __common_interrupt arch/x86/kernel/irq.c:249 [inline] common_interrupt+0x120/0x200 arch/x86/kernel/irq.c:239 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:619 native_restore_fl arch/x86/include/asm/irqflags.h:41 [inline] arch_local_irq_restore arch/x86/include/asm/irqflags.h:84 [inline] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irqrestore+0x25/0x50 kernel/locking/spinlock.c:191 spin_unlock_irqrestore include/linux/spinlock.h:409 [inline] i8042_command+0x12e/0x150 drivers/input/serio/i8042.c:352 i8042_aux_write+0xd7/0x120 drivers/input/serio/i8042.c:387 serio_write include/linux/serio.h:125 [inline] ps2_do_sendbyte+0x2ca/0x710 drivers/input/serio/libps2.c:40 ps2_sendbyte+0x58/0x150 drivers/input/serio/libps2.c:92 cypress_ps2_sendbyte+0x2e/0x160 drivers/input/mouse/cypress_ps2.c:42 cypress_ps2_read_cmd_status drivers/input/mouse/cypress_ps2.c:116 [inline] cypress_send_ext_cmd+0x1d0/0x8d0 drivers/input/mouse/cypress_ps2.c:189 cypress_detect+0x75/0x190 drivers/input/mouse/cypress_ps2.c:205 psmouse_do_detect drivers/input/mouse/psmouse-base.c:1009 [inline] psmouse_try_protocol+0x211/0x370 drivers/input/mouse/psmouse-base.c:1023 psmouse_extensions+0x557/0x930 drivers/input/mouse/psmouse-base.c:1146 psmouse_switch_protocol+0x52a/0x740 drivers/input/mouse/psmouse-base.c:1542 psmouse_connect+0x5e6/0xfc0 drivers/input/mouse/psmouse-base.c:1632 serio_connect_driver drivers/input/serio/serio.c:47 [inline] serio_driver_probe+0x72/0xa0 drivers/input/serio/serio.c:778 really_probe+0x291/0xde0 drivers/base/dd.c:554 driver_probe_device+0x26b/0x3d0 drivers/base/dd.c:738 device_driver_attach+0x228/0x290 drivers/base/dd.c:1013 __driver_attach+0x15b/0x2f0 drivers/base/dd.c:1090 bus_for_each_dev+0x147/0x1d0 drivers/base/bus.c:305 serio_attach_driver drivers/input/serio/serio.c:808 [inline] serio_handle_event+0x5f6/0xa30 drivers/input/serio/serio.c:227 process_one_work+0x933/0x15a0 kernel/workqueue.c:2272 worker_thread+0x64c/0x1120 kernel/workqueue.c:2418 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5435 [inline] lock_acquire+0x2a3/0x8c0 kernel/locking/lockdep.c:5400 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:159 input_inject_event+0xa6/0x310 drivers/input/input.c:466 __led_set_brightness drivers/leds/led-core.c:48 [inline] led_set_brightness_nopm drivers/leds/led-core.c:275 [inline] led_set_brightness_nosleep+0xe6/0x1a0 drivers/leds/led-core.c:292 led_set_brightness+0x134/0x170 drivers/leds/led-core.c:267 led_trigger_event drivers/leds/led-triggers.c:387 [inline] led_trigger_event+0x70/0xd0 drivers/leds/led-triggers.c:377 kbd_led_trigger_activate+0xfa/0x130 drivers/tty/vt/keyboard.c:1017 led_trigger_set+0x61e/0xbd0 drivers/leds/led-triggers.c:195 led_trigger_set_default drivers/leds/led-triggers.c:259 [inline] led_trigger_set_default+0x1a6/0x230 drivers/leds/led-triggers.c:246 led_classdev_register_ext+0x5b1/0x7c0 drivers/leds/led-class.c:417 led_classdev_register include/linux/leds.h:190 [inline] input_leds_connect+0x3fb/0x740 drivers/input/input-leds.c:139 input_attach_handler+0x180/0x1f0 drivers/input/input.c:1031 input_register_device.cold+0xf0/0x307 drivers/input/input.c:2229 atkbd_connect+0x736/0xa00 drivers/input/keyboard/atkbd.c:1293 serio_connect_driver drivers/input/serio/serio.c:47 [inline] serio_driver_probe+0x72/0xa0 drivers/input/serio/serio.c:778 really_probe+0x291/0xde0 drivers/base/dd.c:554 driver_probe_device+0x26b/0x3d0 drivers/base/dd.c:738 device_driver_attach+0x228/0x290 drivers/base/dd.c:1013 __driver_attach+0x15b/0x2f0 drivers/base/dd.c:1090 bus_for_each_dev+0x147/0x1d0 drivers/base/bus.c:305 serio_attach_driver drivers/input/serio/serio.c:808 [inline] serio_handle_event+0x5f6/0xa30 drivers/input/serio/serio.c:227 process_one_work+0x933/0x15a0 kernel/workqueue.c:2272 worker_thread+0x64c/0x1120 kernel/workqueue.c:2418 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 } ... key at: [<ffffffff8fa35f00>] __key.8+0x0/0x40 ... acquired at: __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] evdev_pass_values.part.0+0xf6/0x970 drivers/input/evdev.c:261 evdev_pass_values drivers/input/evdev.c:253 [inline] evdev_events+0x28b/0x3f0 drivers/input/evdev.c:306 input_to_handler+0x2a0/0x4c0 drivers/input/input.c:115 input_pass_values.part.0+0x284/0x700 drivers/input/input.c:145 input_pass_values drivers/input/input.c:134 [inline] input_handle_event+0x324/0x1400 drivers/input/input.c:399 input_inject_event+0x2f5/0x310 drivers/input/input.c:471 evdev_write+0x430/0x760 drivers/input/evdev.c:530 vfs_write+0x28e/0xa30 fs/read_write.c:603 ksys_write+0x1ee/0x250 fs/read_write.c:658 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> (&client->buffer_lock){....}-{2:2} { INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5435 [inline] lock_acquire+0x2a3/0x8c0 kernel/locking/lockdep.c:5400 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] evdev_pass_values.part.0+0xf6/0x970 drivers/input/evdev.c:261 evdev_pass_values drivers/input/evdev.c:253 [inline] evdev_events+0x28b/0x3f0 drivers/input/evdev.c:306 input_to_handler+0x2a0/0x4c0 drivers/input/input.c:115 input_pass_values.part.0+0x284/0x700 drivers/input/input.c:145 input_pass_values drivers/input/input.c:134 [inline] input_handle_event+0x324/0x1400 drivers/input/input.c:399 input_inject_event+0x2f5/0x310 drivers/input/input.c:471 evdev_write+0x430/0x760 drivers/input/evdev.c:530 vfs_write+0x28e/0xa30 fs/read_write.c:603 ksys_write+0x1ee/0x250 fs/read_write.c:658 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 } ... key at: [<ffffffff8fa36400>] __key.4+0x0/0x40 ... acquired at: __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:223 kill_fasync_rcu fs/fcntl.c:1004 [inline] kill_fasync fs/fcntl.c:1025 [inline] kill_fasync+0x14b/0x460 fs/fcntl.c:1018 __pass_event drivers/input/evdev.c:240 [inline] evdev_pass_values.part.0+0x64e/0x970 drivers/input/evdev.c:278 evdev_pass_values drivers/input/evdev.c:253 [inline] evdev_events+0x28b/0x3f0 drivers/input/evdev.c:306 input_to_handler+0x2a0/0x4c0 drivers/input/input.c:115 input_pass_values.part.0+0x284/0x700 drivers/input/input.c:145 input_pass_values drivers/input/input.c:134 [inline] input_handle_event+0x324/0x1400 drivers/input/input.c:399 input_inject_event+0x2f5/0x310 drivers/input/input.c:471 evdev_write+0x430/0x760 drivers/input/evdev.c:530 vfs_write+0x28e/0xa30 fs/read_write.c:603 ksys_write+0x1ee/0x250 fs/read_write.c:658 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> (&new->fa_lock){.+..}-{2:2} { HARDIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5435 [inline] lock_acquire+0x2a3/0x8c0 kernel/locking/lockdep.c:5400 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:223 kill_fasync_rcu fs/fcntl.c:1004 [inline] kill_fasync fs/fcntl.c:1025 [inline] kill_fasync+0x14b/0x460 fs/fcntl.c:1018 sock_wake_async+0xd2/0x160 net/socket.c:1331 sk_wake_async include/net/sock.h:2263 [inline] sk_wake_async include/net/sock.h:2259 [inline] sock_def_error_report+0x2cd/0x4c0 net/core/sock.c:2878 sock_queue_err_skb+0x37b/0x750 net/core/skbuff.c:4540 __skb_complete_tx_timestamp+0x308/0x420 net/core/skbuff.c:4635 __skb_tstamp_tx+0x402/0x770 net/core/skbuff.c:4723 __dev_queue_xmit+0x1dd4/0x2da0 net/core/dev.c:4075 packet_snd net/packet/af_packet.c:3005 [inline] packet_sendmsg+0x2413/0x52b0 net/packet/af_packet.c:3030 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x331/0x810 net/socket.c:2362 ___sys_sendmsg+0xf3/0x170 net/socket.c:2416 __sys_sendmmsg+0x195/0x470 net/socket.c:2506 __do_sys_sendmmsg net/socket.c:2535 [inline] __se_sys_sendmmsg net/socket.c:2532 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2532 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5435 [inline] lock_acquire+0x2a3/0x8c0 kernel/locking/lockdep.c:5400 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:223 kill_fasync_rcu fs/fcntl.c:1004 [inline] kill_fasync fs/fcntl.c:1025 [inline] kill_fasync+0x14b/0x460 fs/fcntl.c:1018 __pass_event drivers/input/evdev.c:240 [inline] evdev_pass_values.part.0+0x64e/0x970 drivers/input/evdev.c:278 evdev_pass_values drivers/input/evdev.c:253 [inline] evdev_events+0x28b/0x3f0 drivers/input/evdev.c:306 input_to_handler+0x2a0/0x4c0 drivers/input/input.c:115 input_pass_values.part.0+0x284/0x700 drivers/input/input.c:145 input_pass_values drivers/input/input.c:134 [inline] input_handle_event+0x324/0x1400 drivers/input/input.c:399 input_inject_event+0x2f5/0x310 drivers/input/input.c:471 evdev_write+0x430/0x760 drivers/input/evdev.c:530 vfs_write+0x28e/0xa30 fs/read_write.c:603 ksys_write+0x1ee/0x250 fs/read_write.c:658 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 } ... key at: [<ffffffff8ef71d00>] __key.0+0x0/0x40 ... acquired at: mark_usage kernel/locking/lockdep.c:4310 [inline] __lock_acquire+0x1216/0x5c00 kernel/locking/lockdep.c:4784 lock_acquire kernel/locking/lockdep.c:5435 [inline] lock_acquire+0x2a3/0x8c0 kernel/locking/lockdep.c:5400 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:223 kill_fasync_rcu fs/fcntl.c:1004 [inline] kill_fasync fs/fcntl.c:1025 [inline] kill_fasync+0x14b/0x460 fs/fcntl.c:1018 sock_wake_async+0xd2/0x160 net/socket.c:1331 sk_wake_async include/net/sock.h:2263 [inline] sk_wake_async include/net/sock.h:2259 [inline] sock_def_error_report+0x2cd/0x4c0 net/core/sock.c:2878 sock_queue_err_skb+0x37b/0x750 net/core/skbuff.c:4540 __skb_complete_tx_timestamp+0x308/0x420 net/core/skbuff.c:4635 __skb_tstamp_tx+0x402/0x770 net/core/skbuff.c:4723 __dev_queue_xmit+0x1dd4/0x2da0 net/core/dev.c:4075 packet_snd net/packet/af_packet.c:3005 [inline] packet_sendmsg+0x2413/0x52b0 net/packet/af_packet.c:3030 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x331/0x810 net/socket.c:2362 ___sys_sendmsg+0xf3/0x170 net/socket.c:2416 __sys_sendmmsg+0x195/0x470 net/socket.c:2506 __do_sys_sendmmsg net/socket.c:2535 [inline] __se_sys_sendmmsg net/socket.c:2532 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2532 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 stack backtrace: CPU: 0 PID: 8500 Comm: syz-executor335 Not tainted 5.10.0-rc4-next-20201117-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 print_irq_inversion_bug kernel/locking/lockdep.c:3738 [inline] check_usage_backwards kernel/locking/lockdep.c:3882 [inline] mark_lock_irq kernel/locking/lockdep.c:3972 [inline] mark_lock.cold+0x1a/0x74 kernel/locking/lockdep.c:4409 mark_usage kernel/locking/lockdep.c:4310 [inline] __lock_acquire+0x1216/0x5c00 kernel/locking/lockdep.c:4784 lock_acquire kernel/locking/lockdep.c:5435 [inline] lock_acquire+0x2a3/0x8c0 kernel/locking/lockdep.c:5400 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:223 kill_fasync_rcu fs/fcntl.c:1004 [inline] kill_fasync fs/fcntl.c:1025 [inline] kill_fasync+0x14b/0x460 fs/fcntl.c:1018 sock_wake_async+0xd2/0x160 net/socket.c:1331 sk_wake_async include/net/sock.h:2263 [inline] sk_wake_async include/net/sock.h:2259 [inline] sock_def_error_report+0x2cd/0x4c0 net/core/sock.c:2878 sock_queue_err_skb+0x37b/0x750 net/core/skbuff.c:4540 __skb_complete_tx_timestamp+0x308/0x420 net/core/skbuff.c:4635 __skb_tstamp_tx+0x402/0x770 net/core/skbuff.c:4723 __dev_queue_xmit+0x1dd4/0x2da0 net/core/dev.c:4075 packet_snd net/packet/af_packet.c:3005 [inline] packet_sendmsg+0x2413/0x52b0 net/packet/af_packet.c:3030 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x331/0x810 net/socket.c:2362 ___sys_sendmsg+0xf3/0x170 net/socket.c:2416 __sys_sendmmsg+0x195/0x470 net/socket.c:2506 __do_sys_sendmmsg net/socket.c:2535 [inline] __se_sys_sendmmsg net/socket.c:2532 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2532 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x4473f9 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 0b d2 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fff03c98f98 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00000000004aae61 RCX: 00000000004473f9 RDX: 000000000400004e RSI: 0000000020000d00 RDI: 0000000000000005 RBP: 00007fff03c98fa0 R08: 0000000001bbbbbb R09: 0000000001bbbbbb R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff03c98fb0 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
