mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-06 08:46:46 +00:00
exit: panic before exit_mm() on global init exit
commit 43cf75d964
upstream.
Currently, when global init and all threads in its thread-group have exited
we panic via:
do_exit()
-> exit_notify()
-> forget_original_parent()
-> find_child_reaper()
This makes it hard to extract a useable coredump for global init from a
kernel crashdump because by the time we panic exit_mm() will have already
released global init's mm.
This patch moves the panic futher up before exit_mm() is called. As was the
case previously, we only panic when global init and all its threads in the
thread-group have exited.
Signed-off-by: chenqiwu <chenqiwu@xiaomi.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
[christian.brauner@ubuntu.com: fix typo, rewrite commit message]
Link: https://lore.kernel.org/r/1576736993-10121-1-git-send-email-qiwuchen55@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
858f090696
commit
66d9052e6c
1 changed files with 8 additions and 4 deletions
|
@ -517,10 +517,6 @@ static struct task_struct *find_child_reaper(struct task_struct *father,
|
|||
}
|
||||
|
||||
write_unlock_irq(&tasklist_lock);
|
||||
if (unlikely(pid_ns == &init_pid_ns)) {
|
||||
panic("Attempted to kill init! exitcode=0x%08x\n",
|
||||
father->signal->group_exit_code ?: father->exit_code);
|
||||
}
|
||||
|
||||
list_for_each_entry_safe(p, n, dead, ptrace_entry) {
|
||||
list_del_init(&p->ptrace_entry);
|
||||
|
@ -766,6 +762,14 @@ void __noreturn do_exit(long code)
|
|||
acct_update_integrals(tsk);
|
||||
group_dead = atomic_dec_and_test(&tsk->signal->live);
|
||||
if (group_dead) {
|
||||
/*
|
||||
* If the last thread of global init has exited, panic
|
||||
* immediately to get a useable coredump.
|
||||
*/
|
||||
if (unlikely(is_global_init(tsk)))
|
||||
panic("Attempted to kill init! exitcode=0x%08x\n",
|
||||
tsk->signal->group_exit_code ?: (int)code);
|
||||
|
||||
#ifdef CONFIG_POSIX_TIMERS
|
||||
hrtimer_cancel(&tsk->signal->real_timer);
|
||||
exit_itimers(tsk->signal);
|
||||
|
|
Loading…
Reference in a new issue