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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+0x1424/0x1700 arch/x86/kernel/unwind_orc.c:441
Read of size 8 at addr ffff8881e3477d30 by task syz-executor.2/24332

CPU: 1 PID: 24332 Comm: syz-executor.2 Not tainted 4.14.184-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+0x54/0x1dc mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0xa9/0x2b9 mm/kasan/report.c:393
 deref_stack_regs arch/x86/kernel/unwind_orc.c:311 [inline]
 unwind_next_frame+0x1424/0x1700 arch/x86/kernel/unwind_orc.c:441
 __save_stack_trace+0x6b/0xd0 arch/x86/kernel/stacktrace.c:44
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xaf/0x190 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kmem_cache_free+0x7c/0x2b0 mm/slab.c:3758
 __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+0x78d/0x1180 kernel/rcu/tree.c:2946
 __do_softirq+0x254/0x9bf kernel/softirq.c:288
 invoke_softirq kernel/softirq.c:368 [inline]
 irq_exit+0x15b/0x1a0 kernel/softirq.c:409
 exiting_irq arch/x86/include/asm/apic.h:648 [inline]
 smp_apic_timer_interrupt+0x141/0x5f0 arch/x86/kernel/apic/apic.c:1102
 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:793
 </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_acquire+0x97/0x3f0 kernel/locking/lockdep.c:3993
RSP: 0018:ffff8881e3477c00 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10
RAX: 1ffffffff0f62cd0 RBX: ffff8880968b6300 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff8880968b6b84
RBP: ffff8880a979d560 R08: 0000000000000001 R09: 0000000000000000
R10: ffff8881e3477dd8 R11: ffff8880968b6300 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
 __pipe_lock fs/pipe.c:88 [inline]
 pipe_release+0x49/0x240 fs/pipe.c:583
 __pipe_lock fs/pipe.c:88 [inline]
 pipe_release+0x49/0x240 fs/pipe.c:583
 retint_kernel+0x2d/0x2d
RIP: 876de690:0x41b58ab3
RSP: 0000:1ffff1103c68efb4 EFLAGS: ffffffff8199a630 ORIG_RAX: 1ffff1103c68efa6
RAX: ffff88809613b080 RBX: ffffffff876c7a70 RCX: 000000011fff705c
RDX: ffff88809a072a90 RSI: 0000000000000000 RDI: 0000000000000010
RBP: 0000000041b58ab3 R08: 000000101fff7050 R09: 00000140f3265a00
R10: ffffffff81003d3b R11: ffffffff863d90b0 R12: ffffffff8199aec7
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000002

The buggy address belongs to the page:
page:ffffea00078d1dc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x57ffe0000000000()
raw: 057ffe0000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 0000000100000001 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881e3477c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881e3477c80: 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00
>ffff8881e3477d00: 00 f2 00 00 00 f2 f2 f2 00 00 00 00 00 f3 f3 f3
                                     ^
 ffff8881e3477d80: f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881e3477e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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