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BUG: KCSAN: data-race in yama_ptracer_del / yama_ptracer_del

write to 0xffff888084e50a90 of 1 bytes by interrupt on cpu 1:
 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:1550
 __put_task_struct+0xc3/0x350 kernel/fork.c:751
 put_task_struct include/linux/sched/task.h:122 [inline]
 delayed_put_task_struct+0x19b/0x1c0 kernel/exit.c:182
 rcu_do_batch kernel/rcu/tree.c:2207 [inline]
 rcu_core+0x533/0x9f0 kernel/rcu/tree.c:2434
 rcu_core_si+0x12/0x20 kernel/rcu/tree.c:2443
 __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:1146
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 clear_page_erms+0x9/0x10 arch/x86/lib/clear_page_64.S:49

read to 0xffff888084e50a90 of 1 bytes by interrupt on cpu 0:
 yama_ptracer_del+0xd4/0x1a0 security/yama/yama_lsm.c:187
 yama_task_free+0x1e/0x30 security/yama/yama_lsm.c:207
 security_task_free+0x3f/0xa0 security/security.c:1550
 __put_task_struct+0xc3/0x350 kernel/fork.c:751
 put_task_struct include/linux/sched/task.h:122 [inline]
 delayed_put_task_struct+0x19b/0x1c0 kernel/exit.c:182
 rcu_do_batch kernel/rcu/tree.c:2207 [inline]
 rcu_core+0x533/0x9f0 kernel/rcu/tree.c:2434
 rcu_core_si+0x12/0x20 kernel/rcu/tree.c:2443
 __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:1146
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline]
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
 _raw_spin_unlock_irqrestore+0x4d/0x80 kernel/locking/spinlock.c:191
 do_wait+0x220/0x4c0 kernel/exit.c:1469
 kernel_wait4+0x146/0x230 kernel/exit.c:1617
 __do_sys_wait4+0xea/0x100 kernel/exit.c:1629
 __se_sys_wait4 kernel/exit.c:1625 [inline]
 __x64_sys_wait4+0x59/0x70 kernel/exit.c:1625
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7776 Comm: syz-executor.1 Not tainted 5.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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