syzbot

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BUG: KCSAN: data-race in yama_ptracer_del / yama_relation_cleanup

write to 0xffff88809a574250 of 1 bytes by interrupt on cpu 0:
 yama_ptracer_del+0x117/0x1a0 security/yama/yama_lsm.c:191
 yama_task_free+0x1e/0x30 security/yama/yama_lsm.c:207
 security_task_free+0x3f/0xa0 security/security.c:1569
 __put_task_struct+0xc3/0x350 kernel/fork.c:748
 put_task_struct include/linux/sched/task.h:126 [inline]
 delayed_put_task_struct+0x19b/0x1c0 kernel/exit.c:173
 rcu_do_batch kernel/rcu/tree.c:2206 [inline]
 rcu_core+0x533/0x9f0 kernel/rcu/tree.c:2433
 rcu_core_si+0x12/0x20 kernel/rcu/tree.c:2442
 __do_softirq+0x118/0x34a kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0xb5/0xd0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:546 [inline]
 smp_apic_timer_interrupt+0xe2/0x270 arch/x86/kernel/apic/apic.c:1140
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 get_current arch/x86/include/asm/current.h:15 [inline]
 __sanitizer_cov_trace_pc+0x9/0x50 kernel/kcov.c:186
 get_timespec64+0x102/0x150 kernel/time/time.c:800
 __do_sys_nanosleep kernel/time/hrtimer.c:1958 [inline]
 __se_sys_nanosleep kernel/time/hrtimer.c:1953 [inline]
 __x64_sys_nanosleep+0x4e/0x190 kernel/time/hrtimer.c:1953
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88809a574250 of 1 bytes by task 45 on cpu 1:
 yama_relation_cleanup+0xbb/0x1b0 security/yama/yama_lsm.c:122
 process_one_work+0x424/0x930 kernel/workqueue.c:2268
 worker_thread+0x9a/0x7e0 kernel/workqueue.c:2414
 kthread+0x203/0x230 kernel/kthread.c:268
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 45 Comm: kworker/1:1 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events yama_relation_cleanup
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