The patch titled
Subject: exit: pidns: alloc_pid() leaks pid_namespace if child_reaper is exiting
has been added to the -mm tree. Its filename is
exit-pidns-alloc_pid-leaks-pid_namespace-if-child_reaper-is-exiting.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/exit-pidns-alloc_pid-leaks-pid_namespace-if-child_reaper-is-exiting.patch
echo and later at
echo http://ozlabs.org/~akpm/mmotm/broken-out/exit-pidns-alloc_pid-leaks-pid_namespace-if-child_reaper-is-exiting.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Oleg Nesterov <oleg@xxxxxxxxxx>
Subject: exit: pidns: alloc_pid() leaks pid_namespace if child_reaper is exiting
alloc_pid() does get_pid_ns() beforehand but forgets to put_pid_ns() if it
fails because disable_pid_allocation() was called by the exiting
child_reaper. We can move get_pid_ns() down to successful return.
While at it, simplify/cleanup the "goto out" mess, no need to confuse the
success/error return paths.
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Aaron Tomlin <atomlin@xxxxxxxxxx>
Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Cc: Pavel Emelyanov <xemul@xxxxxxxxxxxxx>
Cc: Serge Hallyn <serge.hallyn@xxxxxxxxxx>
Cc: Sterling Alexander <stalexan@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
kernel/pid.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff -puN kernel/pid.c~exit-pidns-alloc_pid-leaks-pid_namespace-if-child_reaper-is-exiting kernel/pid.c
--- a/kernel/pid.c~exit-pidns-alloc_pid-leaks-pid_namespace-if-child_reaper-is-exiting
+++ a/kernel/pid.c
@@ -320,7 +320,6 @@ struct pid *alloc_pid(struct pid_namespa
goto out_free;
}
- get_pid_ns(ns);
atomic_set(&pid->count, 1);
for (type = 0; type < PIDTYPE_MAX; ++type)
INIT_HLIST_HEAD(&pid->tasks[type]);
@@ -336,7 +335,7 @@ struct pid *alloc_pid(struct pid_namespa
}
spin_unlock_irq(&pidmap_lock);
-out:
+ get_pid_ns(ns);
return pid;
out_unlock:
@@ -346,8 +345,8 @@ out_free:
free_pidmap(pid->numbers + i);
kmem_cache_free(ns->pid_cachep, pid);
- pid = NULL;
- goto out;
+out:
+ return NULL;
}
void disable_pid_allocation(struct pid_namespace *ns)
_
Patches currently in -mm which might be from oleg@xxxxxxxxxx are
mmfs-introduce-helpers-around-the-i_mmap_mutex.patch
mm-use-new-helper-functions-around-the-i_mmap_mutex.patch
mm-convert-i_mmap_mutex-to-rwsem.patch
mm-rmap-share-the-i_mmap_rwsem.patch
uprobes-share-the-i_mmap_rwsem.patch
mm-xip-share-the-i_mmap_rwsem.patch
mm-memory-failure-share-the-i_mmap_rwsem.patch
mm-nommu-share-the-i_mmap_rwsem.patch
mm-memoryc-share-the-i_mmap_rwsem.patch
remove-unnecessary-is_valid_nodemask.patch
proc-task_state-read-cred-group_info-outside-of-task_lock.patch
proc-task_state-deuglify-the-max_fds-calculation.patch
proc-task_state-move-the-main-seq_printf-outside-of-rcu_read_lock.patch
proc-task_state-ptrace_parent-doesnt-need-pid_alive-check.patch
sched_show_task-fix-unsafe-usage-of-real_parent.patch
exit-reparent-use-ptrace_entry-rather-than-sibling-for-exit_dead-tasks.patch
exit-reparent-cleanup-the-changing-of-parent.patch
exit-reparent-cleanup-the-changing-of-parent-fix.patch
exit-reparent-cleanup-the-usage-of-reparent_leader.patch
exit-ptrace-shift-reap-dead-code-from-exit_ptrace-to-forget_original_parent.patch
usermodehelper-dont-use-clone_vfork-for-____call_usermodehelper.patch
usermodehelper-kill-the-kmod_thread_locker-logic.patch
exit-wait-cleanup-the-ptrace_reparented-checks.patch
exit-wait-cleanup-the-ptrace_reparented-checks-fix.patch
exit-wait-dont-use-zombie-real_parent.patch
exit-wait-drop-tasklist_lock-before-psig-c-accounting.patch
exit-release_task-fix-the-comment-about-group-leader-accounting.patch
exit-proc-dont-try-to-flush-proc-tgid-task-tgid.patch
exit-reparent-fix-the-dead-parent-pr_set_child_subreaper-reparenting.patch
exit-reparent-fix-the-cross-namespace-pr_set_child_subreaper-reparenting.patch
exit-reparent-s-while_each_thread-for_each_thread-in-find_new_reaper.patch
exit-reparent-document-the-has_child_subreaper-checks.patch
exit-reparent-introduce-find_child_reaper.patch
exit-reparent-introduce-find_alive_thread.patch
exit-reparent-avoid-find_new_reaper-if-no-children.patch
exit-reparent-call-forget_original_parent-under-tasklist_lock.patch
exit-exit_notify-re-use-dead-list-to-autoreap-current.patch
exit-reparent-fix-update-the-comments-in-zap_pid_ns_processes.patch
exit-pidns-alloc_pid-leaks-pid_namespace-if-child_reaper-is-exiting.patch
linux-next.patch
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