The patch titled
pgrp: exit_notify: fix kill_orphaned_pgrp() usage with mt exit
has been added to the -mm tree. Its filename is
exit_notify-fix-kill_orphaned_pgrp-usage-with-mt-exit.patch
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See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
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The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: pgrp: exit_notify: fix kill_orphaned_pgrp() usage with mt exit
From: Oleg Nesterov <oleg@xxxxxxxxxx>
1. exit_notify() always calls kill_orphaned_pgrp(). This is wrong, we
should do this only when the whole process exits.
2. exit_notify() uses "current" as "ignored_task", obviously wrong.
Use ->group_leader instead.
Test case:
void hup(int sig)
{
printf("HUP received\n");
}
void *tfunc(void *arg)
{
sleep(2);
printf("sub-thread exited\n");
return NULL;
}
int main(int argc, char *argv[])
{
if (!fork()) {
signal(SIGHUP, hup);
kill(getpid(), SIGSTOP);
exit(0);
}
pthread_t thr;
pthread_create(&thr, NULL, tfunc, NULL);
sleep(1);
printf("main thread exited\n");
syscall(__NR_exit, 0);
return 0;
}
output:
main thread exited
HUP received
Hangup
With this patch the output is:
main thread exited
sub-thread exited
HUP received
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Roland McGrath <roland@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
kernel/exit.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff -puN kernel/exit.c~exit_notify-fix-kill_orphaned_pgrp-usage-with-mt-exit kernel/exit.c
--- a/kernel/exit.c~exit_notify-fix-kill_orphaned_pgrp-usage-with-mt-exit
+++ a/kernel/exit.c
@@ -750,7 +750,7 @@ static void forget_original_parent(struc
* Send signals to all our closest relatives so that they know
* to properly mourn us..
*/
-static void exit_notify(struct task_struct *tsk)
+static void exit_notify(struct task_struct *tsk, int group_dead)
{
int state;
@@ -766,7 +766,8 @@ static void exit_notify(struct task_stru
exit_task_namespaces(tsk);
write_lock_irq(&tasklist_lock);
- kill_orphaned_pgrp(tsk, NULL);
+ if (group_dead)
+ kill_orphaned_pgrp(tsk->group_leader, NULL);
/* Let father know we died
*
@@ -981,7 +982,7 @@ NORET_TYPE void do_exit(long code)
module_put(tsk->binfmt->module);
proc_exit_connector(tsk);
- exit_notify(tsk);
+ exit_notify(tsk, group_dead);
#ifdef CONFIG_NUMA
mpol_free(tsk->mempolicy);
tsk->mempolicy = NULL;
_
Patches currently in -mm which might be from oleg@xxxxxxxxxx are
git-hrt.patch
kthread-call-wake_up_process-without-the-lock-being-held.patch
documentation-atomic_add_unless-doesnt-imply-mb-on-failure-fix.patch
mmap_region-cleanup-the-final-vma_merge-related-code.patch
remove-unused-variable-from-send_signal.patch
turn-legacy_queue-macro-into-static-inline-function.patch
consolidate-checking-for-ignored-legacy-signals.patch
consolidate-checking-for-ignored-legacy-signals-simplify.patch
signals-do_signal_stop-use-signal_group_exit.patch
signals-do_group_exit-use-signal_group_exit-more-consistently.patch
lock_task_sighand-add-rcu-lock-unlock.patch
k_getrusage-dont-take-rcu_read_lock.patch
do_task_stat-dont-take-rcu_read_lock.patch
signals-consolidate-checks-for-whether-or-not-to-ignore-a-signal.patch
signals-clean-dequeue_signal-from-excess-checks-and-assignments.patch
signals-consolidate-send_sigqueue-and-send_group_sigqueue.patch
signals-cleanup-security_task_kill-usage-implementation.patch
introduce-kill_orphaned_pgrp-helper.patch
will_become_orphaned_pgrp-partially-fix-insufficient-exit_state-check.patch
exit_notify-fix-kill_orphaned_pgrp-usage-with-mt-exit.patch
ptrace-introduce-task_detached-helper.patch
ptrace-introduce-ptrace_reparented-helper.patch
reparent_thread-use-same_thread_group.patch
document-de_thread-with-exit_notify-connection.patch
workqueues-shrink-cpu_populated_map-when-cpu-dies.patch
workqueues-shrink-cpu_populated_map-when-cpu-dies-fix.patch
cleanup_workqueue_thread-remove-the-unneeded-cpu-parameter.patch
simplify-cpu_hotplug_begin-put_online_cpus.patch
redo-locking-of-tty-pgrp.patch
resume-tty-on-susp-and-fix-crnl-order-in-n_tty-line-discipline.patch
procfs-task-exe-symlink.patch
procfs-task-exe-symlink-fix.patch
procfs-task-exe-symlink-fix-2.patch
free_pidmap-turn-it-into-free_pidmapstruct-upid.patch
put_pid-make-sure-we-dont-free-the-live-pid.patch
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