syzbot

==================================================================
BUG: KCSAN: data-race in do_notify_parent_cldstop / wait_consider_task

write to 0xffff888121e7851c of 4 bytes by task 24188 on cpu 0:
 wait_task_stopped kernel/exit.c:1328 [inline]
 wait_consider_task+0xaa8/0x1680 kernel/exit.c:1514
 ptrace_do_wait kernel/exit.c:1554 [inline]
 __do_wait+0x13e/0x500 kernel/exit.c:1662
 do_wait+0xaf/0x270 kernel/exit.c:1692
 kernel_wait4+0x164/0x1d0 kernel/exit.c:1851
 __do_sys_wait4 kernel/exit.c:1879 [inline]
 __se_sys_wait4 kernel/exit.c:1875 [inline]
 __x64_sys_wait4+0x94/0x120 kernel/exit.c:1875
 x64_sys_call+0x2529/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:62
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888121e7851c of 4 bytes by task 24190 on cpu 1:
 do_notify_parent_cldstop+0x1a8/0x2a0 kernel/signal.c:2202
 ptrace_stop+0x327/0x5a0 kernel/signal.c:2320
 ptrace_signal+0x52/0x240 kernel/signal.c:2626
 get_signal+0x820/0x1070 kernel/signal.c:2804
 arch_do_signal_or_restart+0x95/0x4b0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x59/0x130 kernel/entry/common.c:218
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x00000013 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 24190 Comm: syz.0.17335 Tainted: G        W          6.12.0-rc2-syzkaller-00307-g36c254515dc6 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================