syzbot

==================================================================
BUG: KCSAN: data-race in acct_collect / do_exit

write to 0xffff888123f9b4fc of 4 bytes by task 27596 on cpu 1:
 reparent_leader kernel/exit.c:601 [inline]
 forget_original_parent kernel/exit.c:653 [inline]
 exit_notify kernel/exit.c:669 [inline]
 do_exit+0x95f/0x1560 kernel/exit.c:846
 do_group_exit+0xce/0x180 kernel/exit.c:923
 get_signal+0xf83/0x1510 kernel/signal.c:2855
 arch_do_signal_or_restart+0x8c/0x2c0 arch/x86/kernel/signal.c:868
 handle_signal_work kernel/entry/common.c:148 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x113/0x190 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:300
 do_syscall_64+0x50/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888123f9b4fc of 4 bytes by task 27597 on cpu 0:
 thread_group_leader include/linux/sched/signal.h:669 [inline]
 acct_collect+0x162/0x400 kernel/acct.c:552
 do_exit+0x39f/0x1560 kernel/exit.c:805
 do_group_exit+0xce/0x180 kernel/exit.c:923
 get_signal+0xf83/0x1510 kernel/signal.c:2855
 arch_do_signal_or_restart+0x8c/0x2c0 arch/x86/kernel/signal.c:868
 handle_signal_work kernel/entry/common.c:148 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x113/0x190 kernel/entry/common.c:207
 irqentry_exit_to_user_mode+0x5/0x10 kernel/entry/common.c:313
 irqentry_exit+0xe/0x40 kernel/entry/common.c:404
 exc_general_protection+0x31a/0x4b0 arch/x86/kernel/traps.c:562
 asm_exc_general_protection+0x1e/0x30

value changed: 0x00000000 -> 0x00000011

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 27597 Comm: syz-executor.0 Not tainted 5.15.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================