================================================================== BUG: KASAN: stack-out-of-bounds in csd_lock_record+0xcb/0xe0 kernel/smp.c:118 Read of size 8 at addr ffffc90008136e30 by task kworker/u4:2/26 CPU: 0 PID: 26 Comm: kworker/u4:2 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: __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 __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:__rcu_read_unlock+0x23/0x560 kernel/rcu/tree_plugin.h:389 Code: 4f f1 ff ff 0f 1f 00 48 b8 00 00 00 00 00 fc ff df 41 57 41 56 41 55 41 54 55 65 48 8b 2c 25 c0 fe 01 00 48 8d bd 78 03 00 00 <53> 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 3f 01 RSP: 0018:ffffc90000e27c50 EFLAGS: 00000293 RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffffff87cecf98 RDX: ffff8880a90440c0 RSI: ffffffff87cecca6 RDI: ffff8880a9044438 RBP: ffff8880a90440c0 R08: 0000000000000000 R09: ffffffff8c5a7a27 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: dffffc0000000000 R15: 00000000000001dc rcu_read_unlock include/linux/rcupdate.h:687 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:411 [inline] batadv_nc_worker+0x78b/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: ffffc90008136d00: 00 00 f1 f1 f1 f1 00 00 00 00 00 00 00 00 00 00 ffffc90008136d80: 00 f3 f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 >ffffc90008136e00: 00 00 00 f1 f1 f1 f1 00 00 00 f3 f3 f3 f3 f3 00 ^ ffffc90008136e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90008136f00: 00 00 00 00 00 00 00 f1 f1 f1 f1 f1 f1 00 00 00 ==================================================================