syzbot

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BUG: KASAN: stack-out-of-bounds in deref_stack_regs arch/x86/kernel/unwind_orc.c:308 [inline]
BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x1757/0x1810 arch/x86/kernel/unwind_orc.c:437
Read of size 8 at addr ffff888181fe79f0 by task syz-executor030/19726

CPU: 0 PID: 19726 Comm: syz-executor030 Not tainted 4.14.154+ #0
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xe5/0x154 lib/dump_stack.c:58
 print_address_description+0x60/0x226 mm/kasan/report.c:187
 __kasan_report.cold+0x1a/0x41 mm/kasan/report.c:316
 deref_stack_regs arch/x86/kernel/unwind_orc.c:308 [inline]
 unwind_next_frame+0x1757/0x1810 arch/x86/kernel/unwind_orc.c:437
 perf_callchain_kernel+0x3a0/0x540 arch/x86/events/core.c:2338
 get_perf_callchain+0x2f5/0x770 kernel/events/callchain.c:217
 perf_callchain+0x147/0x190 kernel/events/callchain.c:190
 perf_prepare_sample+0x6a8/0x1360 kernel/events/core.c:6149
 __perf_event_output kernel/events/core.c:6265 [inline]
 perf_event_output_forward+0xdc/0x220 kernel/events/core.c:6283
 __perf_event_overflow+0x12d/0x340 kernel/events/core.c:7541
 perf_swevent_hrtimer+0x238/0x390 kernel/events/core.c:8746
 __run_hrtimer kernel/time/hrtimer.c:1259 [inline]
 __hrtimer_run_queues+0x28b/0xc40 kernel/time/hrtimer.c:1323
 hrtimer_interrupt+0x1bd/0x490 kernel/time/hrtimer.c:1357
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline]
 smp_apic_timer_interrupt+0x147/0x650 arch/x86/kernel/apic/apic.c:1100
 apic_timer_interrupt+0x8c/0xa0 arch/x86/entry/entry_64.S:792
 </IRQ>
RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:774 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:796 [inline]
RIP: 0010:lock_is_held_type+0x54/0x150 kernel/locking/lockdep.c:4028
RSP: 0018:ffff888181fe7880 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 0000000000000000 RBX: ffff888181fd8000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffff888181fd882c
RBP: ffffffff936d51a0 R08: 0000000000000001 R09: ffffed103aec44fa
R10: ffffed103aec44f9 R11: ffff8881d76227cf R12: ffffffff91c4b7f9
R13: 0000000000000000 R14: ffff888181fe7910 R15: dffffc0000000000
 security_free_mnt_opts include/linux/security.h:189 [inline]
 superblock_doinit+0x189/0x220 security/selinux/hooks.c:1220
 retint_kernel+0x2d/0x2d
RIP: 0010:0xffffffff00000001
RSP: 0018:ffff888181fe7a08 EFLAGS: 00000296 ORIG_RAX: ffffffffffffff10
RAX: ffffffff9346d427 RBX: ffff888181f0e000 RCX: ffffffff91c4b8b0
RDX: 0000000041b58ab3 RSI: ffffffff93447f2c RDI: ffffffff91402fa0
RBP: ffff888181f94400 R08: 0000000041b58ab3 R09: ffffffff91c4b951
R10: ffff888181dabc00 R11: 0000000000400000 R12: 1ffff110303fcf34
R13: 400834fc30512b00 R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea000607f9c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: ffffea000607f9e0 ffffea000607f9e0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888181fe7880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1
 ffff888181fe7900: f1 f1 00 00 00 f3 f3 f3 f3 f3 00 00 00 00 00 00
>ffff888181fe7980: 00 00 00 00 f1 f1 f1 f1 00 00 00 00 f3 f3 f3 f3
                                                             ^
 ffff888181fe7a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888181fe7a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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