==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x387e/0x4b50 kernel/locking/lockdep.c:3092
Read of size 8 at addr ffff8801cf43d4b8 by task syz-executor4/5961

CPU: 0 PID: 5961 Comm: syz-executor4 Not tainted 4.4.113-gef588ef #33
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 955b01de0f27aed0 ffff8800b398f650 ffffffff81d0278d
 ffffea00073d0f00 ffff8801cf43d4b8 0000000000000000 ffff8801cf43d4b8
 0000000000000000 ffff8800b398f688 ffffffff814fd053 ffff8801cf43d4b8
Call Trace:
 [<ffffffff81d0278d>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d0278d>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff814fd053>] print_address_description+0x73/0x260 mm/kasan/report.c:252
 [<ffffffff814fd565>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff814fd565>] kasan_report+0x285/0x370 mm/kasan/report.c:408
 [<ffffffff814fd6c4>] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:429
 [<ffffffff81239c3e>] __lock_acquire+0x387e/0x4b50 kernel/locking/lockdep.c:3092
 [<ffffffff8123c77e>] lock_acquire+0x15e/0x460 kernel/locking/lockdep.c:3592
 [<ffffffff8377172e>] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:112 [inline]
 [<ffffffff8377172e>] _raw_spin_lock_irqsave+0x4e/0x70 kernel/locking/spinlock.c:159
 [<ffffffff8121f0a4>] remove_wait_queue+0x14/0x40 kernel/sched/wait.c:49
 [<ffffffff815f57d8>] ep_remove_wait_queue fs/eventpoll.c:530 [inline]
 [<ffffffff815f57d8>] ep_unregister_pollwait.isra.6+0xa8/0x220 fs/eventpoll.c:548
 [<ffffffff815f6503>] ep_free+0x93/0x1c0 fs/eventpoll.c:765
 [<ffffffff815f6674>] ep_eventpoll_release+0x44/0x60 fs/eventpoll.c:797
 [<ffffffff81522363>] __fput+0x233/0x6d0 fs/file_table.c:208
 [<ffffffff81522885>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8118b9d4>] task_work_run+0x104/0x180 kernel/task_work.c:115
 [<ffffffff81132f7a>] exit_task_work include/linux/task_work.h:21 [inline]
 [<ffffffff81132f7a>] do_exit+0x82a/0x2a10 kernel/exit.c:755
 [<ffffffff81139418>] do_group_exit+0x108/0x320 kernel/exit.c:885
 [<ffffffff8115c872>] get_signal+0x4f2/0x1550 kernel/signal.c:2317
 [<ffffffff8100e7fb>] do_signal+0x8b/0x1d40 arch/x86/kernel/signal.c:712
 [<ffffffff810035fa>] exit_to_usermode_loop+0x11a/0x160 arch/x86/entry/common.c:247
 [<ffffffff81006535>] prepare_exit_to_usermode arch/x86/entry/common.c:282 [inline]
 [<ffffffff81006535>] syscall_return_slowpath+0x1b5/0x1f0 arch/x86/entry/common.c:347
 [<ffffffff83771ce9>] int_ret_from_sys_call+0x25/0xa3

Allocated by task 5961:
 [<ffffffff81035df6>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814fc0c3>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814fc38d>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814fc38d>] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:616
 [<ffffffff814f8310>] kmem_cache_alloc_trace+0x100/0x2b0 mm/slub.c:2642
 [<ffffffff82c7b46d>] kmalloc include/linux/slab.h:476 [inline]
 [<ffffffff82c7b46d>] kzalloc include/linux/slab.h:620 [inline]
 [<ffffffff82c7b46d>] binder_get_thread+0x15d/0x750 drivers/android/binder.c:4452
 [<ffffffff82c7baaa>] binder_poll+0x4a/0x210 drivers/android/binder.c:4555
 [<ffffffff815f9651>] ep_item_poll fs/eventpoll.c:806 [inline]
 [<ffffffff815f9651>] ep_insert fs/eventpoll.c:1319 [inline]
 [<ffffffff815f9651>] SYSC_epoll_ctl fs/eventpoll.c:1934 [inline]
 [<ffffffff815f9651>] SyS_epoll_ctl+0x10b1/0x2040 fs/eventpoll.c:1833
 [<ffffffff83771b5f>] entry_SYSCALL_64_fastpath+0x1c/0x98

Freed by task 5961:
 [<ffffffff81035df6>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814fc0c3>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814fc9e2>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814fc9e2>] kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:589
 [<ffffffff814f947c>] slab_free_hook mm/slub.c:1383 [inline]
 [<ffffffff814f947c>] slab_free_freelist_hook mm/slub.c:1405 [inline]
 [<ffffffff814f947c>] slab_free mm/slub.c:2859 [inline]
 [<ffffffff814f947c>] kfree+0xfc/0x300 mm/slub.c:3749
 [<ffffffff82c749d1>] binder_free_thread drivers/android/binder.c:4480 [inline]
 [<ffffffff82c749d1>] binder_thread_dec_tmpref+0x1c1/0x250 drivers/android/binder.c:2036
 [<ffffffff82c7550d>] binder_thread_release+0x27d/0x540 drivers/android/binder.c:4544
 [<ffffffff82c90134>] binder_ioctl+0xb94/0x12e0 drivers/android/binder.c:4760
 [<ffffffff815588ca>] vfs_ioctl fs/ioctl.c:43 [inline]
 [<ffffffff815588ca>] do_vfs_ioctl+0x7aa/0xee0 fs/ioctl.c:607
 [<ffffffff8155908f>] SYSC_ioctl fs/ioctl.c:622 [inline]
 [<ffffffff8155908f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:613
 [<ffffffff83771b5f>] entry_SYSCALL_64_fastpath+0x1c/0x98

The buggy address belongs to the object at ffff8801cf43d400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 184 bytes inside of
 512-byte region [ffff8801cf43d400, ffff8801cf43d600)
The buggy address belongs to the page:
BUG: unable to handle kernel 
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 5950 Comm: syz-executor2 Not tainted 4.4.113-gef588ef #33
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8800b48f2f80 task.stack: ffff8800b16a0000
RIP: 0010:[<ffffffff8427cd06>]  [<ffffffff8427cd06>] kasan_die_notifier+0x6/0x20
RSP: 0018:ffff8800b16a7298  EFLAGS: 00010046
RAX: 000000000000001d RBX: ffffffff8383ca60 RCX: ffffffff81269242
RDX: 0000000000010000 RSI: ffffc90002718000 RDI: ffff8800b48f37ec
RBP: ffffffff810f0d38 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: fffffbfff0ad7e25 R12: ffff8800b16a7298
R13: ffffffff810c83f0 R14: dffffc0000000000 R15: ffff8800b16a7298
FS:  00007f9c15f81700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000002 CR3: 00000000b4532000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8800b16a72f8 ffffffff81194138 0000000000000000 dffffc0000000000
 ffffffff811956b4 0000000000000008 0000000000000000 0000000000000001
 0000000000000008 ffff8800b16a7368 ffff8800b16a7318 ffff8800b16a7330
Call Trace:
Code: 83 ff ff ff ff c0 f2 83 83 ff ff ff ff 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 20 0d 0f 81 ff ff <ff> ff 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
RIP  [<ffffffff8427cd06>] kasan_die_notifier+0x6/0x20
 RSP <ffff8800b16a7298>
---[ end trace 8af3b4cdec36d8df ]---