==================================================================
BUG: KCSAN: data-race in yama_task_free / yama_task_free

write to 0xffff88810dd8b390 of 1 bytes by interrupt on cpu 0:
 yama_ptracer_del security/yama/yama_lsm.c:191 [inline]
 yama_task_free+0xc3/0x160 security/yama/yama_lsm.c:207
 security_task_free+0x3f/0xa0 security/security.c:1597
 __put_task_struct+0xc2/0x3a0 kernel/fork.c:736
 put_task_struct include/linux/sched/task.h:111 [inline]
 delayed_put_task_struct+0x4e/0x130 kernel/exit.c:173
 rcu_do_batch kernel/rcu/tree.c:2489 [inline]
 rcu_core+0x69b/0xb90 kernel/rcu/tree.c:2723
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2736
 __do_softirq+0x13c/0x2c3 kernel/softirq.c:343
 asm_call_irq_on_stack+0xf/0x20
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0x32/0x40 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:226 [inline]
 __irq_exit_rcu+0xb4/0xc0 kernel/softirq.c:420
 sysvec_apic_timer_interrupt+0x74/0x90 arch/x86/kernel/apic/apic.c:1096
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:628
 clear_page_erms+0x7/0x10 arch/x86/lib/clear_page_64.S:48
 clear_page arch/x86/include/asm/page_64.h:49 [inline]
 clear_highpage include/linux/highmem.h:203 [inline]
 kernel_init_free_pages mm/page_alloc.c:1212 [inline]
 post_alloc_hook mm/page_alloc.c:2300 [inline]
 prep_new_page mm/page_alloc.c:2306 [inline]
 get_page_from_freelist+0x366/0x630 mm/page_alloc.c:3945
 __alloc_pages_nodemask+0x19e/0x350 mm/page_alloc.c:4995
 __alloc_pages include/linux/gfp.h:511 [inline]
 __alloc_pages_node include/linux/gfp.h:524 [inline]
 alloc_pages_vma+0x718/0x890 mm/mempolicy.c:2211
 do_huge_pmd_anonymous_page+0x643/0x940 mm/huge_memory.c:761
 create_huge_pmd mm/memory.c:4269 [inline]
 __handle_mm_fault mm/memory.c:4493 [inline]
 handle_mm_fault+0x11fb/0x17b0 mm/memory.c:4620
 do_user_addr_fault+0x433/0x830 arch/x86/mm/fault.c:1393
 handle_page_fault arch/x86/mm/fault.c:1450 [inline]
 exc_page_fault+0x94/0x2a0 arch/x86/mm/fault.c:1506
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:580

read to 0xffff88810dd8b390 of 1 bytes by interrupt on cpu 1:
 yama_ptracer_del security/yama/yama_lsm.c:187 [inline]
 yama_task_free+0x5c/0x160 security/yama/yama_lsm.c:207
 security_task_free+0x3f/0xa0 security/security.c:1597
 __put_task_struct+0xc2/0x3a0 kernel/fork.c:736
 put_task_struct include/linux/sched/task.h:111 [inline]
 delayed_put_task_struct+0x4e/0x130 kernel/exit.c:173
 rcu_do_batch kernel/rcu/tree.c:2489 [inline]
 rcu_core+0x69b/0xb90 kernel/rcu/tree.c:2723
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2736
 __do_softirq+0x13c/0x2c3 kernel/softirq.c:343
 asm_call_irq_on_stack+0xf/0x20
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0x32/0x40 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:226 [inline]
 __irq_exit_rcu+0xb4/0xc0 kernel/softirq.c:420
 sysvec_apic_timer_interrupt+0x74/0x90 arch/x86/kernel/apic/apic.c:1096
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:628
 find_watchpoint kernel/kcsan/core.c:128 [inline]
 check_access kernel/kcsan/core.c:616 [inline]
 __tsan_read8+0x2f/0x180 kernel/kcsan/core.c:842
 ext4_get_group_desc+0x85/0x190 fs/ext4/balloc.c:283
 recently_deleted fs/ext4/ialloc.c:682 [inline]
 find_inode_bit+0x16a/0x3a0 fs/ext4/ialloc.c:728
 __ext4_new_inode+0xd22/0x3060 fs/ext4/ialloc.c:1062
 ext4_symlink+0x2bc/0x780 fs/ext4/namei.c:3336
 vfs_symlink+0x216/0x2d0 fs/namei.c:3962
 do_symlinkat+0xee/0x280 fs/namei.c:3989
 __do_sys_symlink fs/namei.c:4008 [inline]
 __se_sys_symlink fs/namei.c:4006 [inline]
 __x64_sys_symlink+0x32/0x40 fs/namei.c:4006
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 13607 Comm: syz-executor.4 Not tainted 5.11.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================