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BUG: KASAN: use-after-free in perf_trace_lock_acquire+0x5b7/0x980 include/trace/events/lock.h:13
Read of size 8 at addr ffff8801c07de138 by task syzkaller201544/6125

CPU: 1 PID: 6125 Comm: syzkaller201544 Not tainted 4.15.0+ #198
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x25b/0x340 mm/kasan/report.c:409
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430
 perf_trace_lock_acquire+0x5b7/0x980 include/trace/events/lock.h:13
 trace_lock_acquire include/trace/events/lock.h:13 [inline]
 lock_acquire+0x394/0x580 kernel/locking/lockdep.c:3919
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152
 remove_wait_queue+0x81/0x350 kernel/sched/wait.c:50
 vhost_poll_stop drivers/vhost/vhost.c:230 [inline]
 vhost_dev_stop+0x15c/0x2a0 drivers/vhost/vhost.c:566
 vhost_net_release+0x6e/0x190 drivers/vhost/net.c:998
 __fput+0x327/0x7e0 fs/file_table.c:210
 ____fput+0x15/0x20 fs/file_table.c:244
 task_work_run+0x199/0x270 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x9bb/0x1ad0 kernel/exit.c:865
 do_group_exit+0x149/0x400 kernel/exit.c:968
 get_signal+0x73a/0x16d0 kernel/signal.c:2467
 do_signal+0x90/0x1eb0 arch/x86/kernel/signal.c:809
 exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:264 [inline]
 do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline]
 do_fast_syscall_32+0xbfd/0xf9d arch/x86/entry/common.c:389
 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129
RIP: 0023:0xf7f19c79
RSP: 002b:00000000f7eb212c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0
RAX: fffffffffffffe00 RBX: 0000000008100f94 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000008100f94
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 6098:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
 kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3610
 kmalloc include/linux/slab.h:499 [inline]
 eventfd_file_create.part.3+0x96/0x250 fs/eventfd.c:441
 eventfd_file_create fs/eventfd.c:483 [inline]
 SYSC_eventfd2 fs/eventfd.c:468 [inline]
 SyS_eventfd2 fs/eventfd.c:458 [inline]
 SYSC_eventfd fs/eventfd.c:485 [inline]
 SyS_eventfd+0x2c/0x80 fs/eventfd.c:483
 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline]
 do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389
 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129

Freed by task 6125:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3488 [inline]
 kfree+0xd6/0x260 mm/slab.c:3803
 eventfd_free_ctx fs/eventfd.c:72 [inline]
 eventfd_free fs/eventfd.c:79 [inline]
 kref_put include/linux/kref.h:70 [inline]
 eventfd_ctx_put+0x26/0x30 fs/eventfd.c:104
 eventfd_release+0x52/0x60 fs/eventfd.c:113
 __fput+0x327/0x7e0 fs/file_table.c:210
 ____fput+0x15/0x20 fs/file_table.c:244
 task_work_run+0x199/0x270 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x9bb/0x1ad0 kernel/exit.c:865
 do_group_exit+0x149/0x400 kernel/exit.c:968
 get_signal+0x73a/0x16d0 kernel/signal.c:2467
 do_signal+0x90/0x1eb0 arch/x86/kernel/signal.c:809
 exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:264 [inline]
 do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline]
 do_fast_syscall_32+0xbfd/0xf9d arch/x86/entry/common.c:389
 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129

The buggy address belongs to the object at ffff8801c07de100
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 56 bytes inside of
 96-byte region [ffff8801c07de100, ffff8801c07de160)
The buggy address belongs to the page:
page:ffffea000701f780 count:1 mapcount:0 mapping:ffff8801c07de000 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801c07de000 0000000000000000 0000000100000020
raw: ffffea00073a3620 ffffea0006cb4760 ffff8801db0004c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c07de000: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff8801c07de080: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
>ffff8801c07de100: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                                        ^
 ffff8801c07de180: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff8801c07de200: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
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