===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected 5.12.0-rc6-syzkaller #0 Not tainted ----------------------------------------------------- syz-executor.4/7964 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffff8880139f7538 (&f->f_owner.lock){.+.?}-{2:2}, at: send_sigio+0x2f/0x300 fs/fcntl.c:795 and this task is already holding: ffff8880245ae0c0 (&new->fa_lock){....}-{2:2}, at: kill_fasync_rcu fs/fcntl.c:1012 [inline] ffff8880245ae0c0 (&new->fa_lock){....}-{2:2}, at: kill_fasync+0x19b/0x440 fs/fcntl.c:1033 which would create a new lock dependency: (&new->fa_lock){....}-{2:2} -> (&f->f_owner.lock){.+.?}-{2:2} but this new dependency connects a SOFTIRQ-irq-safe lock: (fasync_lock){+.+.}-{2:2} ... which became SOFTIRQ-irq-safe at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __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] fasync_remove_entry+0x37/0x1d0 fs/fcntl.c:885 __tty_fasync drivers/tty/tty_io.c:2246 [inline] tty_release+0x182/0xef0 drivers/tty/tty_io.c:1764 __fput+0x352/0x7b0 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:140 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x10b/0x1e0 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x44/0xae to a SOFTIRQ-irq-unsafe lock: (&f->f_owner.lock){.+.?}-{2:2} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0x7b/0xb0 kernel/locking/spinlock.c:231 send_sigurg+0x25/0x370 fs/fcntl.c:834 sk_send_sigurg+0x6a/0xb0 net/core/sock.c:2952 tcp_check_urg net/ipv4/tcp_input.c:5503 [inline] tcp_urg+0x26f/0xa90 net/ipv4/tcp_input.c:5544 tcp_rcv_established+0x920/0x21a0 net/ipv4/tcp_input.c:5878 tcp_v4_do_rcv+0x3a1/0x870 net/ipv4/tcp_ipv4.c:1679 tcp_v4_rcv+0x3ca0/0x4ab0 net/ipv4/tcp_ipv4.c:2062 ip_protocol_deliver_rcu+0x3ca/0x790 net/ipv4/ip_input.c:204 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_local_deliver+0x311/0x490 net/ipv4/ip_input.c:252 __netif_receive_skb_one_core net/core/dev.c:5384 [inline] __netif_receive_skb+0x128/0x3b0 net/core/dev.c:5498 process_backlog+0x478/0x8c0 net/core/dev.c:6365 __napi_poll+0xba/0x4f0 net/core/dev.c:6912 napi_poll net/core/dev.c:6979 [inline] net_rx_action+0x56c/0xdc0 net/core/dev.c:7065 __do_softirq+0x318/0x714 kernel/softirq.c:345 run_ksoftirqd+0x63/0xb0 kernel/softirq.c:652 smpboot_thread_fn+0x572/0x970 kernel/smpboot.c:165 kthread+0x39a/0x3c0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 other info that might help us debug this: Chain exists of: fasync_lock --> &new->fa_lock --> &f->f_owner.lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&f->f_owner.lock); local_irq_disable(); lock(fasync_lock); lock(&new->fa_lock); lock(fasync_lock); *** DEADLOCK *** 8 locks held by syz-executor.4/7964: #0: ffff888144be9110 (&evdev->mutex){+.+.}-{3:3}, at: evdev_write+0x1cf/0x6a0 drivers/input/evdev.c:513 #1: ffff8881438fa230 (&dev->event_lock){-...}-{2:2}, at: input_inject_event+0xb3/0x280 drivers/input/input.c:471 #2: ffffffff8c710280 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:266 #3: ffffffff8c710280 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:266 #4: ffffffff8c710280 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:266 #5: ffff8880750c0028 (&client->buffer_lock){....}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline] #5: ffff8880750c0028 (&client->buffer_lock){....}-{2:2}, at: evdev_pass_values+0xd9/0xaa0 drivers/input/evdev.c:261 #6: ffffffff8c710280 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:266 #7: ffff8880245ae0c0 (&new->fa_lock){....}-{2:2}, at: kill_fasync_rcu fs/fcntl.c:1012 [inline] #7: ffff8880245ae0c0 (&new->fa_lock){....}-{2:2}, at: kill_fasync+0x19b/0x440 fs/fcntl.c:1033 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (fasync_lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __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] fasync_remove_entry+0x37/0x1d0 fs/fcntl.c:885 __tty_fasync drivers/tty/tty_io.c:2246 [inline] tty_release+0x182/0xef0 drivers/tty/tty_io.c:1764 __fput+0x352/0x7b0 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:140 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x10b/0x1e0 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x44/0xae SOFTIRQ-ON-W at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __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] fasync_remove_entry+0x37/0x1d0 fs/fcntl.c:885 __tty_fasync drivers/tty/tty_io.c:2246 [inline] tty_release+0x182/0xef0 drivers/tty/tty_io.c:1764 __fput+0x352/0x7b0 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:140 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x10b/0x1e0 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x44/0xae INITIAL USE at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __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] fasync_remove_entry+0x37/0x1d0 fs/fcntl.c:885 __tty_fasync drivers/tty/tty_io.c:2246 [inline] tty_release+0x182/0xef0 drivers/tty/tty_io.c:1764 __fput+0x352/0x7b0 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:140 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x10b/0x1e0 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x44/0xae } ... key at: [] fasync_lock+0x18/0x80 ... acquired at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __raw_write_lock_irq include/linux/rwlock_api_smp.h:196 [inline] _raw_write_lock_irq+0x6f/0xa0 kernel/locking/spinlock.c:311 fasync_remove_entry+0xff/0x1d0 fs/fcntl.c:890 tun_chr_fasync+0x54/0x140 drivers/net/tun.c:3293 __fput+0x65b/0x7b0 fs/file_table.c:277 task_work_run+0x146/0x1c0 kernel/task_work.c:140 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x10b/0x1e0 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x44/0xae -> (&new->fa_lock){....}-{2:2} { INITIAL USE at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __raw_write_lock_irq include/linux/rwlock_api_smp.h:196 [inline] _raw_write_lock_irq+0x6f/0xa0 kernel/locking/spinlock.c:311 fasync_remove_entry+0xff/0x1d0 fs/fcntl.c:890 tun_chr_fasync+0x54/0x140 drivers/net/tun.c:3293 __fput+0x65b/0x7b0 fs/file_table.c:277 task_work_run+0x146/0x1c0 kernel/task_work.c:140 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x10b/0x1e0 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x44/0xae INITIAL READ USE at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:223 kill_fasync_rcu fs/fcntl.c:1012 [inline] kill_fasync+0x19b/0x440 fs/fcntl.c:1033 __pass_event drivers/input/evdev.c:240 [inline] evdev_pass_values+0x58a/0xaa0 drivers/input/evdev.c:278 evdev_events+0x1c5/0x270 drivers/input/evdev.c:306 input_to_handler drivers/input/input.c:115 [inline] input_pass_values+0x89c/0x11d0 drivers/input/input.c:145 input_handle_event+0xb99/0x1550 drivers/input/input.c:404 input_inject_event+0x1e8/0x280 drivers/input/input.c:476 evdev_write+0x54d/0x6a0 drivers/input/evdev.c:530 vfs_write+0x220/0xab0 fs/read_write.c:603 ksys_write+0x11b/0x220 fs/read_write.c:658 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae } ... key at: [] fasync_insert_entry.__key+0x0/0x40 ... acquired at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0x7b/0xb0 kernel/locking/spinlock.c:231 send_sigio+0x2f/0x300 fs/fcntl.c:795 kill_fasync_rcu fs/fcntl.c:1019 [inline] kill_fasync+0x243/0x440 fs/fcntl.c:1033 __pass_event drivers/input/evdev.c:240 [inline] evdev_pass_values+0x58a/0xaa0 drivers/input/evdev.c:278 evdev_events+0x1c5/0x270 drivers/input/evdev.c:306 input_to_handler drivers/input/input.c:115 [inline] input_pass_values+0x89c/0x11d0 drivers/input/input.c:145 input_handle_event+0xb99/0x1550 drivers/input/input.c:404 input_inject_event+0x1e8/0x280 drivers/input/input.c:476 evdev_write+0x54d/0x6a0 drivers/input/evdev.c:530 vfs_write+0x220/0xab0 fs/read_write.c:603 ksys_write+0x11b/0x220 fs/read_write.c:658 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock: -> (&f->f_owner.lock){.+.?}-{2:2} { HARDIRQ-ON-R at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:223 f_getown_ex fs/fcntl.c:211 [inline] do_fcntl+0xd8/0x12e0 fs/fcntl.c:395 __do_sys_fcntl fs/fcntl.c:471 [inline] __se_sys_fcntl+0xd8/0x1b0 fs/fcntl.c:456 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae IN-SOFTIRQ-R at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0x7b/0xb0 kernel/locking/spinlock.c:231 send_sigurg+0x25/0x370 fs/fcntl.c:834 sk_send_sigurg+0x6a/0xb0 net/core/sock.c:2952 tcp_check_urg net/ipv4/tcp_input.c:5503 [inline] tcp_urg+0x26f/0xa90 net/ipv4/tcp_input.c:5544 tcp_rcv_established+0x920/0x21a0 net/ipv4/tcp_input.c:5878 tcp_v4_do_rcv+0x3a1/0x870 net/ipv4/tcp_ipv4.c:1679 tcp_v4_rcv+0x3ca0/0x4ab0 net/ipv4/tcp_ipv4.c:2062 ip_protocol_deliver_rcu+0x3ca/0x790 net/ipv4/ip_input.c:204 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_local_deliver+0x311/0x490 net/ipv4/ip_input.c:252 __netif_receive_skb_one_core net/core/dev.c:5384 [inline] __netif_receive_skb+0x128/0x3b0 net/core/dev.c:5498 process_backlog+0x478/0x8c0 net/core/dev.c:6365 __napi_poll+0xba/0x4f0 net/core/dev.c:6912 napi_poll net/core/dev.c:6979 [inline] net_rx_action+0x56c/0xdc0 net/core/dev.c:7065 __do_softirq+0x318/0x714 kernel/softirq.c:345 run_ksoftirqd+0x63/0xb0 kernel/softirq.c:652 smpboot_thread_fn+0x572/0x970 kernel/smpboot.c:165 kthread+0x39a/0x3c0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 SOFTIRQ-ON-R at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:223 f_getown_ex fs/fcntl.c:211 [inline] do_fcntl+0xd8/0x12e0 fs/fcntl.c:395 __do_sys_fcntl fs/fcntl.c:471 [inline] __se_sys_fcntl+0xd8/0x1b0 fs/fcntl.c:456 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae INITIAL USE at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __raw_write_lock_irq include/linux/rwlock_api_smp.h:196 [inline] _raw_write_lock_irq+0x6f/0xa0 kernel/locking/spinlock.c:311 f_modown+0x38/0x340 fs/fcntl.c:91 __f_setown fs/fcntl.c:110 [inline] f_setown+0x113/0x1a0 fs/fcntl.c:138 do_fcntl+0x12d/0x12e0 fs/fcntl.c:392 __do_sys_fcntl fs/fcntl.c:471 [inline] __se_sys_fcntl+0xd8/0x1b0 fs/fcntl.c:456 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae INITIAL READ USE at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:223 f_getown_ex fs/fcntl.c:211 [inline] do_fcntl+0xd8/0x12e0 fs/fcntl.c:395 __do_sys_fcntl fs/fcntl.c:471 [inline] __se_sys_fcntl+0xd8/0x1b0 fs/fcntl.c:456 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae } ... key at: [] __alloc_file.__key+0x0/0x10 ... acquired at: lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0x7b/0xb0 kernel/locking/spinlock.c:231 send_sigio+0x2f/0x300 fs/fcntl.c:795 kill_fasync_rcu fs/fcntl.c:1019 [inline] kill_fasync+0x243/0x440 fs/fcntl.c:1033 __pass_event drivers/input/evdev.c:240 [inline] evdev_pass_values+0x58a/0xaa0 drivers/input/evdev.c:278 evdev_events+0x1c5/0x270 drivers/input/evdev.c:306 input_to_handler drivers/input/input.c:115 [inline] input_pass_values+0x89c/0x11d0 drivers/input/input.c:145 input_handle_event+0xb99/0x1550 drivers/input/input.c:404 input_inject_event+0x1e8/0x280 drivers/input/input.c:476 evdev_write+0x54d/0x6a0 drivers/input/evdev.c:530 vfs_write+0x220/0xab0 fs/read_write.c:603 ksys_write+0x11b/0x220 fs/read_write.c:658 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae stack backtrace: CPU: 0 PID: 7964 Comm: syz-executor.4 Not tainted 5.12.0-rc6-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+0x176/0x24e lib/dump_stack.c:120 print_bad_irq_dependency kernel/locking/lockdep.c:2460 [inline] check_irq_usage kernel/locking/lockdep.c:2689 [inline] check_prev_add kernel/locking/lockdep.c:2940 [inline] check_prevs_add+0x4ef0/0x5c20 kernel/locking/lockdep.c:3059 validate_chain kernel/locking/lockdep.c:3674 [inline] __lock_acquire+0x41f7/0x5e60 kernel/locking/lockdep.c:4900 lock_acquire+0x126/0x650 kernel/locking/lockdep.c:5510 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0x7b/0xb0 kernel/locking/spinlock.c:231 send_sigio+0x2f/0x300 fs/fcntl.c:795 kill_fasync_rcu fs/fcntl.c:1019 [inline] kill_fasync+0x243/0x440 fs/fcntl.c:1033 __pass_event drivers/input/evdev.c:240 [inline] evdev_pass_values+0x58a/0xaa0 drivers/input/evdev.c:278 evdev_events+0x1c5/0x270 drivers/input/evdev.c:306 input_to_handler drivers/input/input.c:115 [inline] input_pass_values+0x89c/0x11d0 drivers/input/input.c:145 input_handle_event+0xb99/0x1550 drivers/input/input.c:404 input_inject_event+0x1e8/0x280 drivers/input/input.c:476 evdev_write+0x54d/0x6a0 drivers/input/evdev.c:530 vfs_write+0x220/0xab0 fs/read_write.c:603 ksys_write+0x11b/0x220 fs/read_write.c:658 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x466459 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe20b63c188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000003888 RSI: 0000000020000080 RDI: 0000000000000004 RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffc7bdf4a2f R14: 00007fe20b63c300 R15: 0000000000022000