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BUG: KASAN: out-of-bounds in csd_lock_record+0xcb/0xe0 kernel/smp.c:118
Read of size 8 at addr ffffc900016f7830 by task syz-executor.3/8672

CPU: 1 PID: 8672 Comm: syz-executor.3 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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x8c/0xe0 kernel/locking/spinlock.c:191
Code: 48 c7 c0 00 ff b4 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 37 48 83 3d 9b 74 c8 01 00 74 22 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 95 fb 62 f9 65 8b 05 fe 73 15 78
RSP: 0018:ffffc90005de7a30 EFLAGS: 00000282
RAX: 1ffffffff1369fe0 RBX: 0000000000000282 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000282
RBP: ffff888092dead78 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000282
R13: ffff888092dead78 R14: ffff888092dea5c0 R15: ffff8880ae635e00
 try_to_wake_up+0x617/0x1360 kernel/sched/core.c:2657
 wake_up_process kernel/sched/core.c:2725 [inline]
 wake_up_q+0x96/0x100 kernel/sched/core.c:500
 futex_wake+0x3e9/0x490 kernel/futex.c:1642
 do_futex+0x322/0x1a60 kernel/futex.c:3816
 __do_sys_futex kernel/futex.c:3872 [inline]
 __se_sys_futex kernel/futex.c:3840 [inline]
 __x64_sys_futex+0x378/0x4e0 kernel/futex.c:3840
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:367
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cb29
Code: Bad RIP value.
RSP: 002b:00007fd397fc3cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 000000000078bf08 RCX: 000000000045cb29
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 000000000078bf0c
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000246 R12: 000000000078bf0c
R13: 00007fff357b01cf R14: 00007fd397fc49c0 R15: 000000000078bf0c


Memory state around the buggy address:
 ffffc900016f7700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc900016f7780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc900016f7800: f1 f1 f1 f1 00 00 00 00 f3 f3 f3 f3 00 00 00 00
                                        ^
 ffffc900016f7880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc900016f7900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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