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BUG: KCSAN: data-race in yama_ptracer_del / yama_ptracer_del

write to 0xffff88809fc09250 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

read to 0xffff88809fc09250 of 1 bytes by interrupt on cpu 1:
 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: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
 __read_once_size include/linux/compiler.h:232 [inline]
 arch_atomic64_read arch/x86/include/asm/atomic64_64.h:22 [inline]
 atomic64_read include/asm-generic/atomic-instrumented.h:838 [inline]
 atomic_long_read include/asm-generic/atomic-long.h:29 [inline]
 find_watchpoint kernel/kcsan/core.c:118 [inline]
 check_access kernel/kcsan/core.c:566 [inline]
 __tsan_read1+0x2c/0x110 kernel/kcsan/core.c:767
 insert_queue sound/core/seq/oss/seq_oss_rw.c:164 [inline]
 snd_seq_oss_write+0x10e/0x510 sound/core/seq/oss/seq_oss_rw.c:135
 odev_write+0x4d/0x80 sound/core/seq/oss/seq_oss.c:164
 __vfs_write+0x58/0xb0 fs/read_write.c:495
 vfs_write fs/read_write.c:559 [inline]
 vfs_write+0x189/0x380 fs/read_write.c:543
 ksys_write+0xc5/0x1a0 fs/read_write.c:612
 __do_sys_write fs/read_write.c:624 [inline]
 __se_sys_write fs/read_write.c:621 [inline]
 __x64_sys_write+0x49/0x60 fs/read_write.c:621
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 15489 Comm: syz-executor.5 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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