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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 ffffc90001637950 by task syz-fuzzer/6801

CPU: 0 PID: 6801 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:
 __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
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline]
 sysvec_call_function_single+0x4f/0x120 arch/x86/kernel/smp.c:243
 asm_sysvec_call_function_single+0x12/0x20 arch/x86/include/asm/idtentry.h:604
RIP: 0033:0x410892
Code: Bad RIP value.
RSP: 002b:000000c00021d7b0 EFLAGS: 00000296
RAX: ebdc7d61a00f8af0 RBX: 000000c001500498 RCX: 0000000000000000
RDX: 00000000008fa9c0 RSI: 000000c000112bd0 RDI: 0000000000000038
RBP: 000000c00021d7e0 R08: 0000000000000000 R09: 0000000000000004
R10: 000000c001500480 R11: 0000000037db250c R12: 0000000000000003
R13: 0000000000000001 R14: 0000000000000021 R15: ffffffffffffffff


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 f1 f1 f1 f1 00 00 00 00 f3 f3 f3 f3
                                                 ^
 ffffc90001637980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90001637a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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