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BUG: KASAN: stack-out-of-bounds in unwind_get_return_address+0x96/0xa0 arch/x86/kernel/unwind_frame.c:17
Read of size 8 at addr ffff880175b1f300 by task syz-executor2/18055

CPU: 0 PID: 18055 Comm: syz-executor2 Not tainted 4.9.149+ #5
 ffff880175b1f0b0 ffffffff81b47f01 0000000000000000 ffffea0005d6c7c0
 ffff880175b1f300 0000000000000008 ffffffff810ab576 ffff880175b1f0e8
 ffffffff815020d5 0000000000000000 ffff880175b1f300 ffff880175b1f300
Call Trace:
 [<ffffffff81b47f01>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b47f01>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
 [<ffffffff815020d5>] print_address_description+0x6f/0x238 mm/kasan/report.c:256
 [<ffffffff8150232a>] kasan_report_error mm/kasan/report.c:355 [inline]
 [<ffffffff8150232a>] kasan_report mm/kasan/report.c:412 [inline]
 [<ffffffff8150232a>] kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:397
 [<ffffffff814f4524>] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 [<ffffffff810ab576>] unwind_get_return_address+0x96/0xa0 arch/x86/kernel/unwind_frame.c:17
 [<ffffffff8100fea0>] perf_callchain_kernel+0x3b0/0x540 arch/x86/events/core.c:2278
 [<ffffffff813ecc8b>] get_perf_callchain+0x30b/0x7e0 kernel/events/callchain.c:215
 [<ffffffff813ed2b3>] perf_callchain+0x153/0x1a0 kernel/events/callchain.c:188
 [<ffffffff813e010f>] perf_prepare_sample+0xa4f/0xea0 kernel/events/core.c:5967
 [<ffffffff813e065e>] __perf_event_output kernel/events/core.c:6080 [inline]
 [<ffffffff813e065e>] perf_event_output_forward+0xfe/0x240 kernel/events/core.c:6098
 [<ffffffff813cb5d1>] __perf_event_overflow+0x121/0x330 kernel/events/core.c:7198
 [<ffffffff813cbcec>] perf_swevent_overflow+0x17c/0x210 kernel/events/core.c:7274
 [<ffffffff813cbf2c>] perf_swevent_event+0x1ac/0x280 kernel/events/core.c:7307
 [<ffffffff813e3119>] do_perf_sw_event kernel/events/core.c:7415 [inline]
 [<ffffffff813e3119>] ___perf_sw_event+0x299/0x4c0 kernel/events/core.c:7446
 [<ffffffff828069b0>] perf_sw_event_sched include/linux/perf_event.h:1057 [inline]
 [<ffffffff828069b0>] perf_event_task_sched_out include/linux/perf_event.h:1095 [inline]
 [<ffffffff828069b0>] prepare_task_switch kernel/sched/core.c:2757 [inline]
 [<ffffffff828069b0>] context_switch kernel/sched/core.c:2919 [inline]
 [<ffffffff828069b0>] __schedule+0x1150/0x1b50 kernel/sched/core.c:3498
 [<ffffffff82807442>] schedule+0x92/0x1c0 kernel/sched/core.c:3553
 [<ffffffff8129944c>] freezable_schedule include/linux/freezer.h:171 [inline]
 [<ffffffff8129944c>] futex_wait_queue_me+0x2ec/0x5a0 kernel/futex.c:2372
 [<ffffffff8129c1e8>] futex_wait+0x208/0x5d0 kernel/futex.c:2487
 [<ffffffff812a03c9>] do_futex+0x159/0x1a70 kernel/futex.c:3270
 [<ffffffff812a1f33>] SYSC_futex kernel/futex.c:3330 [inline]
 [<ffffffff812a1f33>] SyS_futex+0x253/0x360 kernel/futex.c:3298
 [<ffffffff810056bd>] do_syscall_64+0x1ad/0x570 arch/x86/entry/common.c:285
 [<ffffffff82816153>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

The buggy address belongs to the page:
page:ffffea0005d6c7c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff880175b1f200: 00 f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00
 ffff880175b1f280: 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 f3 f3
>ffff880175b1f300: f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00
                   ^
 ffff880175b1f380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff880175b1f400: 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 f2 f2
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