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BUG: KASAN: stack-out-of-bounds in csd_lock_record+0xcb/0xe0 kernel/smp.c:118
Read of size 8 at addr ffffc90001637950 by task syz-fuzzer/6811

CPU: 1 PID: 6811 Comm: syz-fuzzer Not tainted 5.8.0-rc3-next-20200703-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:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0x5/0x436 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 csd_lock_record+0xcb/0xe0 kernel/smp.c:118
 flush_smp_call_function_queue+0x285/0x730 kernel/smp.c:391
 __sysvec_call_function_single+0x98/0x490 arch/x86/kernel/smp.c:248
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 sysvec_call_function_single+0xe0/0x120 arch/x86/kernel/smp.c:243
 asm_sysvec_call_function_single+0x12/0x20 arch/x86/include/asm/idtentry.h:604
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:765 [inline]
RIP: 0010:lock_acquire+0x270/0xad0 kernel/locking/lockdep.c:4962
Code: 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 f8 06 00 00 48 83 3d 6d c1 5a 08 00 0f 84 a6 05 00 00 48 8b 7c 24 08 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 03 44 24 10 48 c7
RSP: 0018:ffffc90001967cc0 EFLAGS: 00000282
RAX: 1ffffffff1369fe0 RBX: ffff88808b5ae340 RCX: 0000000000000001
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: 0000000000000282
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8c5a7a57
R10: fffffbfff18b4f4a R11: 0000000000000000 R12: 0000000000000001
R13: ffff8880a1ff68e8 R14: 0000000000000000 R15: ffff88808b5ae340
 __might_fault mm/memory.c:4821 [inline]
 __might_fault+0x152/0x1d0 mm/memory.c:4806
 _copy_from_user+0x29/0x190 lib/usercopy.c:12
 copy_from_user include/linux/uaccess.h:144 [inline]
 get_timespec64+0x75/0x220 kernel/time/time.c:787
 __do_sys_nanosleep kernel/time/hrtimer.c:1958 [inline]
 __se_sys_nanosleep kernel/time/hrtimer.c:1953 [inline]
 __x64_sys_nanosleep+0xaa/0x260 kernel/time/hrtimer.c:1953
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:367
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x46068d
Code: Bad RIP value.
RSP: 002b:000000c000051f30 EFLAGS: 00000202 ORIG_RAX: 0000000000000023
RAX: ffffffffffffffda RBX: 0000000000000014 RCX: 000000000046068d
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000c000051f30
RBP: 000000c000051f40 R08: 00000000000af40f R09: 00007fff2db07090
R10: 00000000000307e2 R11: 0000000000000202 R12: 00000000004338c0
R13: 0000000000000000 R14: 0000000000adca10 R15: 0000000000000000


Memory state around the buggy address:
 ffffc90001637800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90001637880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc90001637900: 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 f3
                                                 ^
 ffffc90001637980: f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90001637a00: 00 f1 f1 f1 f1 00 f3 f3 f3 00 00 00 00 00 00 00
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