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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 ffffc9001a547550 by task kworker/u4:1/21

CPU: 0 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc3-next-20200703-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
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:ffffc90000dd7b80 EFLAGS: 00000282
RAX: 1ffffffff1369fe0 RBX: ffff8880a97a8580 RCX: 0000000000000001
RDX: dffffc0000000000 RSI: 73bfd8279e93f92a RDI: 0000000000000282
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8c5a7a27
R10: fffffbfff18b4f44 R11: 0000000000000000 R12: 0000000000000002
R13: ffffffff89bc3040 R14: 0000000000000000 R15: ffff8880a97a8580
 rcu_lock_acquire include/linux/rcupdate.h:241 [inline]
 rcu_read_lock include/linux/rcupdate.h:634 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:407 [inline]
 batadv_nc_worker+0x12d/0xe50 net/batman-adv/network-coding.c:718
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294


Memory state around the buggy address:
 ffffc9001a547400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9001a547480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc9001a547500: 00 00 00 00 f1 f1 f1 f1 00 00 00 00 f3 f3 f3 f3
                                                    ^
 ffffc9001a547580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9001a547600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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