capability: warning: `syz-executor4' uses 32-bit capabilities (legacy support in use)
==================================================================
BUG: KASAN: stack-out-of-bounds in __read_once_size include/linux/compiler.h:193 [inline]
BUG: KASAN: stack-out-of-bounds in update_stack_state+0x62d/0x680 arch/x86/kernel/unwind_frame.c:270
Read of size 8 at addr ffff88804a8fed48 by task syz-executor3/9051

CPU: 0 PID: 9051 Comm: syz-executor3 Not tainted 5.0.0-rc4+ #51
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+0x1db/0x2d0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
 __read_once_size include/linux/compiler.h:193 [inline]
 update_stack_state+0x62d/0x680 arch/x86/kernel/unwind_frame.c:270
 __unwind_start+0xfe/0x2f0 arch/x86/kernel/unwind_frame.c:404
 unwind_start arch/x86/include/asm/unwind.h:54 [inline]
 perf_callchain_kernel+0x2be/0x660 arch/x86/events/core.c:2361
 get_perf_callchain+0x54b/0xc30 kernel/events/callchain.c:202
 perf_callchain+0x16b/0x1c0 kernel/events/core.c:6364
 perf_prepare_sample+0x896/0x16b0 kernel/events/core.c:6391
 __perf_event_output kernel/events/core.c:6506 [inline]
 perf_event_output_forward+0x111/0x2c0 kernel/events/core.c:6524
 __perf_event_overflow+0x236/0x4c0 kernel/events/core.c:7768
 perf_swevent_overflow+0xaa/0x140 kernel/events/core.c:7844
 perf_swevent_event+0x1f7/0x2f0 kernel/events/core.c:7877
 do_perf_sw_event kernel/events/core.c:7985 [inline]
 ___perf_sw_event+0x4af/0x7e0 kernel/events/core.c:8016
 perf_sw_event_sched include/linux/perf_event.h:1071 [inline]
 perf_event_task_sched_out include/linux/perf_event.h:1109 [inline]
 prepare_task_switch kernel/sched/core.c:2628 [inline]
 context_switch kernel/sched/core.c:2809 [inline]
 __schedule+0xd9b/0x1e60 kernel/sched/core.c:3485
 schedule+0xfe/0x350 kernel/sched/core.c:3529
 freezable_schedule include/linux/freezer.h:172 [inline]
 futex_wait_queue_me+0x3d7/0x810 kernel/futex.c:2598
 futex_wait+0x366/0xa40 kernel/futex.c:2713
 do_futex+0x1a8/0x2910 kernel/futex.c:3596
 __do_sys_futex kernel/futex.c:3657 [inline]
 __se_sys_futex kernel/futex.c:3625 [inline]
 __x64_sys_futex+0x459/0x670 kernel/futex.c:3625
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458089
Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f295fdc8cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 000000000073bf08 RCX: 0000000000458089
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000073bf08
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000073bf0c
R13: 00007ffd6d1c144f R14: 00007f295fdc99c0 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea00012a3f80 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x1fffc0000000000()
raw: 01fffc0000000000 0000000000000000 ffffea00012a3f88 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88804a8fec00: 00 00 00 00 00 00 00 00 00 00 00 f3 f3 f3 f3 f3
 ffff88804a8fec80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804a8fed00: 00 00 00 f1 f1 f1 f1 f1 f1 04 f2 00 00 00 f2 f2
                                              ^
 ffff88804a8fed80: f2 f2 f2 f8 f3 f3 f3 00 00 00 00 00 00 00 00 00
 ffff88804a8fee00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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