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BUG: KASAN: stack-out-of-bounds in deref_stack_regs arch/x86/kernel/unwind_orc.c:311 [inline]
BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x146f/0x17d0 arch/x86/kernel/unwind_orc.c:444
Read of size 8 at addr ffff8880ba507cd8 by task syz-executor282/8055

CPU: 1 PID: 8055 Comm: syz-executor282 Not tainted 4.14.203-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x283 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351
 kasan_report mm/kasan/report.c:409 [inline]
 __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430
 deref_stack_regs arch/x86/kernel/unwind_orc.c:311 [inline]
 unwind_next_frame+0x146f/0x17d0 arch/x86/kernel/unwind_orc.c:444
 perf_callchain_kernel+0x38c/0x520 arch/x86/events/core.c:2343
 get_perf_callchain+0x2df/0x740 kernel/events/callchain.c:217
 perf_callchain+0x147/0x190 kernel/events/callchain.c:190
 perf_prepare_sample+0xd77/0x1380 kernel/events/core.c:6163
 __perf_event_output kernel/events/core.c:6279 [inline]
 perf_event_output_forward+0xc9/0x1f0 kernel/events/core.c:6297
 __perf_event_overflow+0x113/0x310 kernel/events/core.c:7542
 perf_swevent_overflow kernel/events/core.c:7618 [inline]
 perf_swevent_event+0x299/0x460 kernel/events/core.c:7646
 perf_tp_event+0x540/0x6e0 kernel/events/core.c:8080
 perf_trace_run_bpf_submit+0x119/0x200 kernel/events/core.c:8050
 perf_trace_lock+0x2d6/0x490 include/trace/events/lock.h:39
 trace_lock_release include/trace/events/lock.h:58 [inline]
 lock_release+0x4df/0x870 kernel/locking/lockdep.c:4016
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:158 [inline]
 _raw_spin_unlock_irqrestore+0x1b/0xe0 kernel/locking/spinlock.c:192
 __debug_check_no_obj_freed lib/debugobjects.c:760 [inline]
 debug_check_no_obj_freed+0x2c0/0x674 lib/debugobjects.c:776
 kfree+0xb9/0x250 mm/slab.c:3814
 __rcu_reclaim kernel/rcu/rcu.h:195 [inline]
 rcu_do_batch kernel/rcu/tree.c:2699 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2929 [inline]
 rcu_process_callbacks+0x780/0x1180 kernel/rcu/tree.c:2946
 __do_softirq+0x254/0xa1d kernel/softirq.c:288
 invoke_softirq kernel/softirq.c:368 [inline]
 irq_exit+0x193/0x240 kernel/softirq.c:409
 exiting_irq arch/x86/include/asm/apic.h:648 [inline]
 smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1102
 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:793
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline]
RIP: 0010:kmem_cache_free+0x173/0x2b0 mm/slab.c:3759
RSP: 0018:ffff8880955f78d0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10
RAX: 0000000000000007 RBX: ffff88809d742a10 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000282
RBP: ffff88823f8301c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000282
R13: ffffffff817a7596 R14: ffff88809d742a20 R15: dead000000000200
 anon_vma_chain_free mm/rmap.c:134 [inline]
 unlink_anon_vmas+0x466/0x7e0 mm/rmap.c:419
 free_pgtables+0x178/0x2b0 mm/memory.c:655
 exit_mmap+0x27f/0x4d0 mm/mmap.c:3059
 __mmput kernel/fork.c:930 [inline]
 mmput kernel/fork.c:951 [inline]
 mmput+0xfa/0x420 kernel/fork.c:946
 exit_mm kernel/exit.c:545 [inline]
 do_exit+0x948/0x27f0 kernel/exit.c:852
 do_group_exit+0x100/0x2e0 kernel/exit.c:962
 get_signal+0x38d/0x1ca0 kernel/signal.c:2423
 do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x4467c9
RSP: 002b:00007ff7c2554db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00000000006dbc28 RCX: 00000000004467c9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006dbc28
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007ffd82b4054f R14: 00007ff7c25559c0 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea0002e941c0 count:1 mapcount:0 mapping:          (null) index:0x0
flags: 0xfff00000000800(reserved)
raw: 00fff00000000800 0000000000000000 0000000000000000 00000001ffffffff
raw: ffffea0002e941e0 ffffea0002e941e0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880ba507b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1
 ffff8880ba507c00: f1 f1 f1 f1 f1 04 f2 00 f3 f3 f3 00 00 00 00 00
>ffff8880ba507c80: 00 00 00 00 00 f1 f1 f1 f1 04 f3 f3 f3 00 00 00
                                                    ^
 ffff8880ba507d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880ba507d80: 00 00 00 00 f1 f1 f1 f1 00 f3 f3 f3 00 00 00 00
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