input: syz1 as /devices/virtual/input/input7 kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 9433 Comm: syz-executor5 Not tainted 4.19.0-rc4-next-20180921+ #77 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__fire_sched_out_preempt_notifiers kernel/sched/core.c:2502 [inline] RIP: 0010:fire_sched_out_preempt_notifiers kernel/sched/core.c:2510 [inline] RIP: 0010:prepare_task_switch kernel/sched/core.c:2616 [inline] RIP: 0010:context_switch kernel/sched/core.c:2795 [inline] RIP: 0010:__schedule+0x1144/0x1ed0 kernel/sched/core.c:3479 Code: 89 e0 48 c1 e8 03 42 80 3c 28 00 0f 85 7e 08 00 00 4d 8b 24 24 4d 85 e4 0f 84 7e f5 ff ff 49 8d 7c 24 10 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 a4 e8 e0 bb 00 fa eb 9d 48 8d bb 28 04 00 00 48 RSP: 0000:ffff880192c3f4d0 EFLAGS: 00010806 RAX: 1bd5a00000000022 RBX: ffff880196fae340 RCX: 1ffff10031e2f8b7 RDX: 0000000040000002 RSI: 0000000000000000 RDI: dead000000000110 RBP: ffff880192c3f6a8 R08: ffff8801b874e240 R09: fffff52001c24847 R10: fffff52001c24847 R11: ffffc9000e12423b R12: dead000000000100 R13: dffffc0000000000 R14: ffff8801dac2cc40 R15: ffff8801b874e240 FS: 00007f382e9fe700(0000) GS:ffff8801dac00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020fdd800 CR3: 00000001b762a000 CR4: 00000000001426f0 Call Trace: preempt_schedule_common+0x1f/0xd0 kernel/sched/core.c:3603 preempt_schedule+0x4d/0x60 kernel/sched/core.c:3629 ___preempt_schedule+0x16/0x18 __kunmap_atomic include/linux/highmem.h:78 [inline] clear_user_highpage include/linux/highmem.h:138 [inline] clear_subpage+0xeb/0x100 mm/memory.c:4406 process_huge_page mm/memory.c:4369 [inline] clear_huge_page+0x1cf/0x490 mm/memory.c:4420 __do_huge_pmd_anonymous_page mm/huge_memory.c:567 [inline] do_huge_pmd_anonymous_page+0x854/0x17e0 mm/huge_memory.c:725 create_huge_pmd mm/memory.c:3625 [inline] __handle_mm_fault+0x3880/0x53e0 mm/memory.c:3829 handle_mm_fault+0x54f/0xc70 mm/memory.c:3895 __do_page_fault+0x673/0xec0 arch/x86/mm/fault.c:1397 do_page_fault+0xed/0x7d1 arch/x86/mm/fault.c:1472 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1139 RIP: 0033:0x401a5c Code: ff 01 64 48 8b 3c 25 00 00 00 00 48 81 c7 08 ff ff ff e8 a7 db 01 00 85 c0 75 13 48 63 44 24 04 48 8b 54 24 18 48 8b 4c 24 08 <48> 89 0c c2 64 f0 83 2c 25 d0 ff ff ff 01 64 f0 83 04 25 d0 ff ff RSP: 002b:00007f382e9fc030 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000860000109120 RDX: 0000000020fdd800 RSI: 0000000000000000 RDI: 00007f382e9fe608 RBP: 0000000020fdd800 R08: 0000000000000090 R09: 0000000000000005 R10: 00000000000000b3 R11: 0000000000000206 R12: 000000002aaaaaab R13: 0000000020fda000 R14: 00000000004c49c2 R15: 0000000000000000 Modules linked in: ====================================================== WARNING: possible circular locking dependency detected 4.19.0-rc4-next-20180921+ #77 Not tainted ------------------------------------------------------ syz-executor5/9433 is trying to acquire lock: 00000000cb2352ae ((console_sem).lock){-.-.}, at: down_trylock+0x13/0x70 kernel/locking/semaphore.c:136 but task is already holding lock: 00000000eba61787 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1125 [inline] 00000000eba61787 (&rq->lock){-.-.}, at: __schedule+0x236/0x1ed0 kernel/sched/core.c:3417 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&rq->lock){-.-.}: __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2d/0x40 kernel/locking/spinlock.c:144 rq_lock kernel/sched/sched.h:1125 [inline] task_fork_fair+0xb0/0x6d0 kernel/sched/fair.c:9674 sched_fork+0x443/0xba0 kernel/sched/core.c:2358 copy_process+0x2585/0x8780 kernel/fork.c:1887 _do_fork+0x1cb/0x11c0 kernel/fork.c:2216 kernel_thread+0x34/0x40 kernel/fork.c:2275 rest_init+0x22/0xe5 init/main.c:408 start_kernel+0x8bc/0x8f7 init/main.c:739 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:452 x86_64_start_kernel+0x76/0x79 arch/x86/kernel/head64.c:433 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242 -> #1 (&p->pi_lock){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152 try_to_wake_up+0xd2/0x12f0 kernel/sched/core.c:1964 wake_up_process+0x10/0x20 kernel/sched/core.c:2128 __up.isra.1+0x1c0/0x2a0 kernel/locking/semaphore.c:262 up+0x13c/0x1c0 kernel/locking/semaphore.c:187 __up_console_sem+0xbe/0x1b0 kernel/printk/printk.c:243 console_unlock+0x80c/0x1150 kernel/printk/printk.c:2426 do_con_write+0x1356/0x23b0 drivers/tty/vt/vt.c:2767 con_write+0x25/0xc0 drivers/tty/vt/vt.c:3116 process_output_block drivers/tty/n_tty.c:580 [inline] n_tty_write+0x6c1/0x11a0 drivers/tty/n_tty.c:2317 do_tty_write drivers/tty/tty_io.c:958 [inline] tty_write+0x3f1/0x880 drivers/tty/tty_io.c:1042 __vfs_write+0x119/0x9f0 fs/read_write.c:485 vfs_write+0x1fc/0x560 fs/read_write.c:549 ksys_write+0x101/0x260 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 ((console_sem).lock){-.-.}: lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3900 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152 down_trylock+0x13/0x70 kernel/locking/semaphore.c:136 __down_trylock_console_sem+0xae/0x200 kernel/printk/printk.c:226 console_trylock+0x15/0xa0 kernel/printk/printk.c:2244 console_trylock_spinning kernel/printk/printk.c:1648 [inline] vprintk_emit+0x322/0x930 kernel/printk/printk.c:1920 vprintk_default+0x28/0x30 kernel/printk/printk.c:1962 vprintk_func+0x7e/0x181 kernel/printk/printk_safe.c:398 printk+0xa7/0xcf kernel/printk/printk.c:1995 kasan_die_handler.cold.22+0x11/0x30 arch/x86/mm/kasan_init_64.c:250 notifier_call_chain+0x17e/0x380 kernel/notifier.c:93 __atomic_notifier_call_chain kernel/notifier.c:183 [inline] atomic_notifier_call_chain+0x96/0x190 kernel/notifier.c:193 notify_die+0x1bd/0x2d0 kernel/notifier.c:549 do_general_protection+0x25b/0x340 arch/x86/kernel/traps.c:573 general_protection+0x1e/0x30 arch/x86/entry/entry_64.S:1138 __fire_sched_out_preempt_notifiers kernel/sched/core.c:2502 [inline] fire_sched_out_preempt_notifiers kernel/sched/core.c:2510 [inline] prepare_task_switch kernel/sched/core.c:2616 [inline] context_switch kernel/sched/core.c:2795 [inline] __schedule+0x1144/0x1ed0 kernel/sched/core.c:3479 preempt_schedule_common+0x1f/0xd0 kernel/sched/core.c:3603 preempt_schedule+0x4d/0x60 kernel/sched/core.c:3629 ___preempt_schedule+0x16/0x18 __kunmap_atomic include/linux/highmem.h:78 [inline] clear_user_highpage include/linux/highmem.h:138 [inline] clear_subpage+0xeb/0x100 mm/memory.c:4406 process_huge_page mm/memory.c:4369 [inline] clear_huge_page+0x1cf/0x490 mm/memory.c:4420 __do_huge_pmd_anonymous_page mm/huge_memory.c:567 [inline] do_huge_pmd_anonymous_page+0x854/0x17e0 mm/huge_memory.c:725 create_huge_pmd mm/memory.c:3625 [inline] __handle_mm_fault+0x3880/0x53e0 mm/memory.c:3829 handle_mm_fault+0x54f/0xc70 mm/memory.c:3895 __do_page_fault+0x673/0xec0 arch/x86/mm/fault.c:1397 do_page_fault+0xed/0x7d1 arch/x86/mm/fault.c:1472 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1139 other info that might help us debug this: Chain exists of: (console_sem).lock --> &p->pi_lock --> &rq->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&rq->lock); lock(&p->pi_lock); lock(&rq->lock); lock((console_sem).lock); *** DEADLOCK *** 3 locks held by syz-executor5/9433: #0: 0000000006ddac79 (&mm->mmap_sem){++++}, at: __do_page_fault+0x3d9/0xec0 arch/x86/mm/fault.c:1326 #1: 00000000eba61787 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1125 [inline] #1: 00000000eba61787 (&rq->lock){-.-.}, at: __schedule+0x236/0x1ed0 kernel/sched/core.c:3417 #2: 00000000112ebfb6 (rcu_read_lock){....}, at: atomic_notifier_call_chain+0x0/0x190 kernel/notifier.c:329 stack backtrace: CPU: 0 PID: 9433 Comm: syz-executor5 Not tainted 4.19.0-rc4-next-20180921+ #77 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+0x1d3/0x2c4 lib/dump_stack.c:113 print_circular_bug.isra.33.cold.54+0x1bd/0x27d 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+0x33e4/0x4ec0 kernel/locking/lockdep.c:3411 lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3900 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152 down_trylock+0x13/0x70 kernel/locking/semaphore.c:136 __down_trylock_console_sem+0xae/0x200 kernel/printk/printk.c:226 console_trylock+0x15/0xa0 kernel/printk/printk.c:2244 console_trylock_spinning kernel/printk/printk.c:1648 [inline] vprintk_emit+0x322/0x930 kernel/printk/printk.c:1920 vprintk_default+0x28/0x30 kernel/printk/printk.c:1962 vprintk_func+0x7e/0x181 kernel/printk/printk_safe.c:398 printk+0xa7/0xcf kernel/printk/printk.c:1995 kasan_die_handler.cold.22+0x11/0x30 arch/x86/mm/kasan_init_64.c:250 notifier_call_chain+0x17e/0x380 kernel/notifier.c:93 __atomic_notifier_call_chain kernel/notifier.c:183 [inline] atomic_notifier_call_chain+0x96/0x190 kernel/notifier.c:193 notify_die+0x1bd/0x2d0 kernel/notifier.c:549 do_general_protection+0x25b/0x340 arch/x86/kernel/traps.c:573 general_protection+0x1e/0x30 arch/x86/entry/entry_64.S:1138 RIP: 0010:__fire_sched_out_preempt_notifiers kernel/sched/core.c:2502 [inline] RIP: 0010:fire_sched_out_preempt_notifiers kernel/sched/core.c:2510 [inline] RIP: 0010:prepare_task_switch kernel/sched/core.c:2616 [inline] RIP: 0010:context_switch kernel/sched/core.c:2795 [inline] RIP: 0010:__schedule+0x1144/0x1ed0 kernel/sched/core.c:3479 Code: 89 e0 48 c1 e8 03 42 80 3c 28 00 0f 85 7e 08 00 00 4d 8b 24 24 4d 85 e4 0f 84 7e f5 ff ff 49 8d 7c 24 10 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 a4 e8 e0 bb 00 fa eb 9d 48 8d bb 28 04 00 00 48 RSP: 0000:ffff880192c3f4d0 EFLAGS: 00010806 RAX: 1bd5a00000000022 RBX: ffff880196fae340 RCX: 1ffff10031e2f8b7 RDX: 0000000040000002 RSI: 0000000000000000 RDI: dead000000000110 RBP: ffff880192c3f6a8 R08: ffff8801b874e240 R09: fffff52001c24847 R10: fffff52001c24847 R11: ffffc9000e12423b R12: dead000000000100 R13: dffffc0000000000 R14: ffff8801dac2cc40 R15: ffff8801b874e240 preempt_schedule_common+0x1f/0xd0 kernel/sched/core.c:3603 preempt_schedule+0x4d/0x60 kernel/sched/core.c:3629 ___preempt_schedule+0x16/0x18 __kunmap_atomic include/linux/highmem.h:78 [inline] clear_user_highpage include/linux/highmem.h:138 [inline] clear_subpage+0xeb/0x100 mm/memory.c:4406 process_huge_page mm/memory.c:4369 [inline] clear_huge_page+0x1cf/0x490 mm/memory.c:4420 __do_huge_pmd_anonymous_page mm/huge_memory.c:567 [inline] do_huge_pmd_anonymous_page+0x854/0x17e0 mm/huge_memory.c:725 create_huge_pmd mm/memory.c:3625 [inline] __handle_mm_fault+0x3880/0x53e0 mm/memory.c:3829 handle_mm_fault+0x54f/0xc70 mm/memory.c:3895 __do_page_fault+0x673/0xec0 arch/x86/mm/fault.c:1397 Lost 24 message(s)! ---[ end trace 7f1c98349632c90e ]--- RIP: 0010:__fire_sched_out_preempt_notifiers kernel/sched/core.c:2502 [inline] RIP: 0010:fire_sched_out_preempt_notifiers kernel/sched/core.c:2510 [inline] RIP: 0010:prepare_task_switch kernel/sched/core.c:2616 [inline] RIP: 0010:context_switch kernel/sched/core.c:2795 [inline] RIP: 0010:__schedule+0x1144/0x1ed0 kernel/sched/core.c:3479 Code: 89 e0 48 c1 e8 03 42 80 3c 28 00 0f 85 7e 08 00 00 4d 8b 24 24 4d 85 e4 0f 84 7e f5 ff ff 49 8d 7c 24 10 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 a4 e8 e0 bb 00 fa eb 9d 48 8d bb 28 04 00 00 48 RSP: 0000:ffff880192c3f4d0 EFLAGS: 00010806 RAX: 1bd5a00000000022 RBX: ffff880196fae340 RCX: 1ffff10031e2f8b7 RDX: 0000000040000002 RSI: 0000000000000000 RDI: dead000000000110 RBP: ffff880192c3f6a8 R08: ffff8801b874e240 R09: fffff52001c24847 R10: fffff52001c24847 R11: ffffc9000e12423b R12: dead000000000100 R13: dffffc0000000000 R14: ffff8801dac2cc40 R15: ffff8801b874e240 FS: 00007f382e9fe700(0000) GS:ffff8801dac00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020fdd800 CR3: 00000001b762a000 CR4: 00000000001426f0