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BUG: KASAN: stack-out-of-bounds in deref_stack_regs arch/x86/kernel/unwind_orc.c:290 [inline]
BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x1595/0x1930 arch/x86/kernel/unwind_orc.c:420
Read of size 8 at addr ffff8881c42b7668 by task syz-executor306/1868

CPU: 0 PID: 1868 Comm: syz-executor306 Not tainted 4.14.90+ #29
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x11b lib/dump_stack.c:53
 print_address_description+0x60/0x22b mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report.cold.6+0x11b/0x2dd mm/kasan/report.c:409
 deref_stack_regs arch/x86/kernel/unwind_orc.c:290 [inline]
 unwind_next_frame+0x1595/0x1930 arch/x86/kernel/unwind_orc.c:420
 perf_callchain_kernel+0x39c/0x540 arch/x86/events/core.c:2334
 get_perf_callchain+0x2eb/0x760 kernel/events/callchain.c:217
 perf_callchain+0x14a/0x190 kernel/events/callchain.c:190
 perf_prepare_sample+0x704/0x13c0 kernel/events/core.c:6140
 __perf_event_output kernel/events/core.c:6256 [inline]
 perf_event_output_forward+0xeb/0x230 kernel/events/core.c:6274
 __perf_event_overflow+0x116/0x320 kernel/events/core.c:7510
 perf_swevent_overflow+0x166/0x1f0 kernel/events/core.c:7586
 perf_swevent_event+0x112/0x270 kernel/events/core.c:7624
 perf_tp_event+0x620/0x7e0 kernel/events/core.c:8048
 perf_trace_run_bpf_submit+0x10f/0x170 kernel/events/core.c:8018
 perf_trace_lock+0x2f6/0x4c0 include/trace/events/lock.h:39
 trace_lock_release include/trace/events/lock.h:58 [inline]
 lock_release+0x4dc/0x720 kernel/locking/lockdep.c:4009
 rcu_lock_release include/linux/rcupdate.h:249 [inline]
 rcu_read_unlock include/linux/rcupdate.h:687 [inline]
 __is_insn_slot_addr+0x139/0x1f0 kernel/kprobes.c:301
 is_kprobe_insn_slot include/linux/kprobes.h:317 [inline]
 kernel_text_address+0x10b/0x120 kernel/extable.c:148
 __kernel_text_address+0x9/0x30 kernel/extable.c:105
 unwind_get_return_address+0x51/0x90 arch/x86/kernel/unwind_orc.c:238
 __save_stack_trace+0x8d/0xf0 arch/x86/kernel/stacktrace.c:45
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc.part.1+0x4f/0xd0 mm/kasan/kasan.c:551
 slab_post_alloc_hook mm/slab.h:442 [inline]
 slab_alloc_node mm/slub.c:2723 [inline]
 slab_alloc mm/slub.c:2731 [inline]
 kmem_cache_alloc+0xe4/0x2b0 mm/slub.c:2736
 kmem_cache_zalloc include/linux/slab.h:651 [inline]
 ebitmap_cpy+0xc4/0x260 security/selinux/ss/ebitmap.c:60
 mls_context_cpy security/selinux/ss/context.h:51 [inline]
 mls_compute_sid+0x24a/0xda0 security/selinux/ss/mls.c:556
 security_compute_sid.part.6+0x76f/0x1080 security/selinux/ss/services.c:1725
 security_compute_sid security/selinux/ss/services.c:1764 [inline]
 security_transition_sid+0xcb/0x120 security/selinux/ss/services.c:1764
 socket_sockcreate_sid security/selinux/hooks.c:4344 [inline]
 selinux_socket_post_create+0x4e9/0x690 security/selinux/hooks.c:4395
 security_socket_post_create+0x8c/0xc0 security/security.c:1347
 __sock_create+0x498/0x600 net/socket.c:1290
 sock_create net/socket.c:1314 [inline]
 SYSC_socket net/socket.c:1344 [inline]
 SyS_socket+0xdf/0x1d0 net/socket.c:1324
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x446409
RSP: 002b:00007fd0c70cedb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 0000000000446409
RDX: 000000000000003a RSI: 0000000000000003 RDI: 000000000000000a
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007ffed22816ff R14: 00007fd0c70cf9c0 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea000710adc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffffea000710ade0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881c42b7500: 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1
 ffff8881c42b7580: f1 04 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2 00 00 00
>ffff8881c42b7600: 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 04
                                                          ^
 ffff8881c42b7680: f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881c42b7700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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