WARNING: can't dereference registers at 0000000049932adc for ip apic_timer_interrupt+0x8c/0xa0 arch/x86/entry/entry_64.S:792
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BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x169f/0x1810 arch/x86/kernel/unwind_orc.c:470
Read of size 8 at addr ffff88819bf07490 by task syz-executor.3/15550

CPU: 1 PID: 15550 Comm: syz-executor.3 Not tainted 4.14.149+ #0
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xca/0x134 lib/dump_stack.c:53
 print_address_description+0x60/0x226 mm/kasan/report.c:187
 __kasan_report.cold+0x1a/0x41 mm/kasan/report.c:316
 unwind_next_frame+0x169f/0x1810 arch/x86/kernel/unwind_orc.c:470
 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:6148
 __perf_event_output kernel/events/core.c:6264 [inline]
 perf_event_output_forward+0xdc/0x220 kernel/events/core.c:6282
 __perf_event_overflow+0x12d/0x340 kernel/events/core.c:7520
 perf_swevent_overflow+0x7a/0xf0 kernel/events/core.c:7596
 perf_swevent_event+0x19c/0x270 kernel/events/core.c:7629
 perf_tp_event+0x633/0x7f0 kernel/events/core.c:8058
 perf_trace_run_bpf_submit kernel/events/core.c:8028 [inline]
 perf_trace_run_bpf_submit+0x113/0x170 kernel/events/core.c:8014
 perf_trace_lock_acquire+0x341/0x4e0 include/trace/events/lock.h:13
 trace_lock_acquire include/trace/events/lock.h:13 [inline]
 lock_acquire+0x279/0x360 kernel/locking/lockdep.c:3993
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152
 alloc_object lib/debugobjects.c:150 [inline]
 __debug_object_init+0x1d2/0x7d0 lib/debugobjects.c:349
 __init_work+0x3f/0x50 kernel/workqueue.c:506
 ext4_alloc_inode+0x443/0x620 fs/ext4/super.c:1034
 alloc_inode+0x5f/0x180 fs/inode.c:209
 new_inode_pseudo+0x14/0xe0 fs/inode.c:891
 new_inode+0x1b/0x40 fs/inode.c:920
 __ext4_new_inode+0x373/0x4850 fs/ext4/ialloc.c:837
 ext4_create+0x1e5/0x510 fs/ext4/namei.c:2597
 lookup_open+0xa74/0x1730 fs/namei.c:3354
 do_last fs/namei.c:3445 [inline]
 path_openat+0xdd5/0x2be0 fs/namei.c:3681
 do_filp_open+0x1a1/0x280 fs/namei.c:3715
 do_sys_open+0x2ca/0x590 fs/open.c:1096
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459a59
RSP: 002b:00007fbfdd14cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a59
RDX: 0000000000000001 RSI: 0000000000141042 RDI: 0000000020000100
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbfdd14d6d4
R13: 00000000004f9a5f R14: 00000000004db5c8 R15: 00000000ffffffff

The buggy address belongs to the page:
page:ffffea00066fc1c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffffea00066fc1e0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88819bf07380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88819bf07400: 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 f1 f1 04
>ffff88819bf07480: f2 00 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00
                         ^
 ffff88819bf07500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88819bf07580: 00 00 00 00 00 f1 f1 f1 f1 00 f3 f3 f3 00 00 00
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