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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 ffff8881dba07720 by task syz-executor664/1835

CPU: 0 PID: 1835 Comm: syz-executor664 Not tainted 4.14.146+ #0
Call Trace:
 <IRQ>
 __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:3990
 rcu_lock_acquire include/linux/rcupdate.h:242 [inline]
 rcu_read_lock include/linux/rcupdate.h:629 [inline]
 nf_hook include/linux/netfilter.h:197 [inline]
 NF_HOOK include/linux/netfilter.h:248 [inline]
 ip_rcv+0x906/0xf55 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x13ad/0x2cf0 net/core/dev.c:4477
 __netif_receive_skb+0x66/0x210 net/core/dev.c:4515
 netif_receive_skb_internal+0x11f/0x5f0 net/core/dev.c:4588
 napi_skb_finish net/core/dev.c:4949 [inline]
 napi_gro_receive+0x206/0x410 net/core/dev.c:4980
 receive_buf+0x503/0x4310 drivers/net/virtio_net.c:852
 virtnet_receive drivers/net/virtio_net.c:1098 [inline]
 virtnet_poll+0x4e6/0x9f0 drivers/net/virtio_net.c:1189
 napi_poll net/core/dev.c:5598 [inline]
 net_rx_action+0x366/0xcd0 net/core/dev.c:5664
 __do_softirq+0x234/0x9ec kernel/softirq.c:288
 invoke_softirq kernel/softirq.c:368 [inline]
 irq_exit+0x114/0x150 kernel/softirq.c:409
 exiting_irq arch/x86/include/asm/apic.h:648 [inline]
 do_IRQ+0x104/0x1c0 arch/x86/kernel/irq.c:242
 common_interrupt+0x8c/0x8c arch/x86/entry/entry_64.S:576
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline]
RIP: 0010:lock_release+0x3de/0x740 kernel/locking/lockdep.c:4013
RSP: 0018:ffff8881d0df7958 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff6e
RAX: 0000000000000007 RBX: 1ffff1103a1bef2e RCX: 1ffff1103a1c7104
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000246
RBP: ffff8881d0e38000 R08: 0000000000000001 R09: 0000000000000000
R10: fffffbfff4e45b9d R11: ffffffffa722dceb R12: 0000000000000000
R13: ffff8881d0e38000 R14: 0000000000000001 R15: ffff8881d0e38828
 rcu_lock_release include/linux/rcupdate.h:247 [inline]
 rcu_read_unlock include/linux/rcupdate.h:685 [inline]
 mntput_no_expire+0xee/0x810 fs/namespace.c:1236
 mntput+0x5c/0x80 fs/namespace.c:1290
 free_fs_struct+0x12/0x60 fs/fs_struct.c:90
 exit_fs+0xdc/0x110 fs/fs_struct.c:109
 do_exit+0x9a8/0x2a20 kernel/exit.c:871
 do_group_exit+0x100/0x2e0 kernel/exit.c:978
 get_signal+0x39f/0x1cc0 kernel/signal.c:2422
 do_signal+0x96/0x15d0 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x11d/0x160 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+0x3a3/0x520 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4467e9
RSP: 002b:00007fee9a6c6db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00000000006dbc28 RCX: 00000000004467e9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006dbc28
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007ffdaa0bd86f R14: 00007fee9a6c79c0 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea00076e81c0 count:1 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000001000(reserved)
raw: 4000000000001000 0000000000000000 0000000000000000 00000001ffffffff
raw: ffffea00076e81e0 ffffea00076e81e0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881dba07600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881dba07680: 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 f1
>ffff8881dba07700: f1 04 f2 00 f3 f3 f3 00 00 00 00 00 00 00 00 00
                               ^
 ffff8881dba07780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881dba07800: 00 00 00 00 00 f1 f1 f1 f1 f1 f1 00 00 00 00 00
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