syzbot

==================================================================
BUG: KASAN: stack-out-of-bounds in __debug_check_no_obj_freed lib/debugobjects.c:775 [inline]
BUG: KASAN: stack-out-of-bounds in debug_check_no_obj_freed+0x467/0x595 lib/debugobjects.c:815
PANIC: double fault, error_code: 0x0
Read of size 8 at addr ffff8801c9db86c8 by task swapper/0/0
CPU: 1 PID: 18418 Comm: syz-executor0 Not tainted 4.18.0-rc3+ #48

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.18.0-rc3+ #48
RIP: 0010:__lock_acquire+0x2e/0x5020 kernel/locking/lockdep.c:3294
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Code: 
Call Trace:
41 
 <IRQ>
57 
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
41 
89 
cf 
41 
56 
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
41 55 
49 89 
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
fd 41 
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
54 
 __debug_check_no_obj_freed lib/debugobjects.c:775 [inline]
 debug_check_no_obj_freed+0x467/0x595 lib/debugobjects.c:815
45 
89 
cc 
 kmem_cache_free+0x216/0x2d0 mm/slab.c:3755
53 
 free_task_struct kernel/fork.c:162 [inline]
 free_task+0x16e/0x1f0 kernel/fork.c:390
65 
4c 
8b 34 
 __put_task_struct+0x2e6/0x620 kernel/fork.c:666
25 40 
ee 
01 
00 48 
83 e4 
 put_task_struct include/linux/sched/task.h:96 [inline]
 delayed_put_task_struct+0x37f/0x490 kernel/exit.c:180
f0 48 
81 
ec 60 
03 00 
00 48 
8b 
45 10 
 __rcu_reclaim kernel/rcu/rcu.h:178 [inline]
 rcu_do_batch kernel/rcu/tree.c:2558 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2818 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2785 [inline]
 rcu_process_callbacks+0xed5/0x1850 kernel/rcu/tree.c:2802
<89> 
94 
24 80 
00 00 
00 
48 
ba 
00 00 
00 00 
00 
fc 
 __do_softirq+0x2e8/0xb17 kernel/softirq.c:288
ff 
df 
48 
89 
84 24 
98 
RSP: 0018:ffff8801c8bffef0 EFLAGS: 00010086
RAX: 0000000000000000 RBX: 1ffff1003918005a RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff88f92620
 invoke_softirq kernel/softirq.c:368 [inline]
 irq_exit+0x1d1/0x200 kernel/softirq.c:408
RBP: ffff8801c8c00278 R08: 0000000000000000 R09: 0000000000000000
 exiting_irq arch/x86/include/asm/apic.h:527 [inline]
 smp_apic_timer_interrupt+0x186/0x730 arch/x86/kernel/apic/apic.c:1052
R10: ffff8801ca1571b8 R11: ffff8801daf236b3 R12: 0000000000000000
R13: ffffffff88f92620 R14: ffff8801968221c0 R15: 0000000000000002
FS:  00007f4e925ec700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff8801c8bffee8 CR3: 000000019de09000 CR4: 00000000001406e0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863