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BUG: KCSAN: data-race in yama_ptracer_del / yama_ptracer_del

write to 0xffff8880a0860e50 of 1 bytes by interrupt on cpu 1:
 yama_ptracer_del+0x119/0x1a0 security/yama/yama_lsm.c:191
 yama_task_free+0x22/0x30 security/yama/yama_lsm.c:207
 security_task_free+0x43/0xa0 security/security.c:1550
 __put_task_struct+0xcd/0x360 kernel/fork.c:745
 put_task_struct include/linux/sched/task.h:122 [inline]
 delayed_put_task_struct+0x1a5/0x1d0 kernel/exit.c:182
 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+0x115/0x33f kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0xbb/0xe0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:546 [inline]
 smp_apic_timer_interrupt+0xe6/0x280 arch/x86/kernel/apic/apic.c:1146
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 __sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:915
 touch_buffer fs/buffer.c:63 [inline]
 __find_get_block+0x246/0x760 fs/buffer.c:1340
 sb_find_get_block include/linux/buffer_head.h:338 [inline]
 recently_deleted fs/ext4/ialloc.c:680 [inline]
 find_inode_bit.isra.0+0x161/0x300 fs/ext4/ialloc.c:720
 __ext4_new_inode+0xd45/0x2f30 fs/ext4/ialloc.c:912
 ext4_mkdir+0x270/0x820 fs/ext4/namei.c:2782
 vfs_mkdir+0x283/0x390 fs/namei.c:3889
 do_mkdirat+0x1ac/0x1f0 fs/namei.c:3912
 __do_sys_mkdir fs/namei.c:3928 [inline]
 __se_sys_mkdir fs/namei.c:3926 [inline]
 __x64_sys_mkdir+0x40/0x50 fs/namei.c:3926
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880a0860e50 of 1 bytes by interrupt on cpu 0:
 yama_ptracer_del+0xd6/0x1a0 security/yama/yama_lsm.c:187
 yama_task_free+0x22/0x30 security/yama/yama_lsm.c:207
 security_task_free+0x43/0xa0 security/security.c:1550
 __put_task_struct+0xcd/0x360 kernel/fork.c:745
 put_task_struct include/linux/sched/task.h:122 [inline]
 delayed_put_task_struct+0x1a5/0x1d0 kernel/exit.c:182
 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+0x115/0x33f kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0xbb/0xe0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:546 [inline]
 smp_apic_timer_interrupt+0xe6/0x280 arch/x86/kernel/apic/apic.c:1146
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 __sanitizer_cov_trace_pc+0x1/0x50 kernel/kcov.c:180
 touch_buffer fs/buffer.c:63 [inline]
 __find_get_block+0x246/0x760 fs/buffer.c:1340
 sb_find_get_block include/linux/buffer_head.h:338 [inline]
 recently_deleted fs/ext4/ialloc.c:680 [inline]
 find_inode_bit.isra.0+0x161/0x300 fs/ext4/ialloc.c:720
 __ext4_new_inode+0xd45/0x2f30 fs/ext4/ialloc.c:912
 ext4_symlink+0x31c/0x9b0 fs/ext4/namei.c:3287
 vfs_symlink fs/namei.c:4201 [inline]
 vfs_symlink+0x218/0x310 fs/namei.c:4187
 do_symlinkat+0x1a5/0x1e0 fs/namei.c:4228
 __do_sys_symlink fs/namei.c:4247 [inline]
 __se_sys_symlink fs/namei.c:4245 [inline]
 __x64_sys_symlink+0x3f/0x50 fs/namei.c:4245
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 13621 Comm: syz-executor.2 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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