syzbot

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BUG: KCSAN: data-race in yama_ptracer_del / yama_ptracer_del

write to 0xffff88809cc656d0 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_once_size include/linux/compiler.h:232 [inline]
 check_kcov_mode kernel/kcov.c:155 [inline]
 __sanitizer_cov_trace_pc+0x22/0x50 kernel/kcov.c:187
 __read_once_size+0x11/0xd0 include/linux/compiler.h:232
 compound_head include/linux/page-flags.h:182 [inline]
 PageActive include/linux/page-flags.h:329 [inline]
 mark_page_accessed+0x1e4/0x4f0 mm/swap.c:385
 touch_buffer fs/buffer.c:63 [inline]
 __find_get_block+0x239/0x7e0 fs/buffer.c:1334
 sb_find_get_block include/linux/buffer_head.h:338 [inline]
 recently_deleted fs/ext4/ialloc.c:682 [inline]
 find_inode_bit.isra.0+0x16d/0x330 fs/ext4/ialloc.c:724
 __ext4_new_inode+0xd7b/0x3020 fs/ext4/ialloc.c:927
 ext4_symlink+0x322/0x9e0 fs/ext4/namei.c:3295
 vfs_symlink fs/namei.c:3937 [inline]
 vfs_symlink+0x216/0x330 fs/namei.c:3923
 do_symlinkat+0x1ac/0x1e0 fs/namei.c:3964
 __do_sys_symlink fs/namei.c:3983 [inline]
 __se_sys_symlink fs/namei.c:3981 [inline]
 __x64_sys_symlink+0x3c/0x50 fs/namei.c:3981
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88809cc656d0 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
 __sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:915
 tomoyo_domain_quota_is_ok+0x223/0x2b0 security/tomoyo/util.c:1071
 tomoyo_supervisor+0x1d9/0xc90 security/tomoyo/common.c:2089
 tomoyo_audit_path_log security/tomoyo/file.c:168 [inline]
 tomoyo_path_permission security/tomoyo/file.c:587 [inline]
 tomoyo_path_permission+0x118/0x150 security/tomoyo/file.c:573
 tomoyo_path_perm+0x292/0x350 security/tomoyo/file.c:838
 tomoyo_path_symlink+0x66/0x90 security/tomoyo/tomoyo.c:206
 security_path_symlink+0xa7/0xe0 security/security.c:1104
 do_symlinkat+0xcd/0x1e0 fs/namei.c:3962
 __do_sys_symlink fs/namei.c:3983 [inline]
 __se_sys_symlink fs/namei.c:3981 [inline]
 __x64_sys_symlink+0x3c/0x50 fs/namei.c:3981
 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: 31374 Comm: syz-executor.3 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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