Kernel threads resource leakage

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Some time ago, I reported problem WRT resource leakage in kernel_thread. (2.4.20) To demonstrate it, I submitted program that uses /proc file to display some info and to start/stop kernel thread. I don't want to re-post this code again.

Finally, I found that resource leak present only if you create kernel_thread as non-root. With my previous example, do "insmod" as root, while perform actual thread creation/destruction (echo "+" >/proc/kthread etc.) as non-root.

To demonstrate it better, I added to /proc 'read' procedure content of "struct user_struct" (current->user).
It makes clear, that in this case current->user->processes do not decremented when thread destroyed, and eventually reaches user limit (usually 4k processes). At this point, this user can do nothing.

Problem leaves in "reparent_to_init" code in kernel/sched.c; there current->user is simply changed to point to INIT_USER without proper resource management.

Does it worth inclusion in 2.4.22?

Following patch fixes this bug. I verified that with this patch applied, kernel_thread behaves properly.

@@ -1274,8 +1274,16 @@
    this_task->cap_permitted = CAP_FULL_SET;
    this_task->keep_capabilities = 0;
    memcpy(this_task->rlim, init_task.rlim, sizeof(*(this_task->rlim)));
-    this_task->user = INIT_USER;
-
+    if (this_task->uid) { /* not root? switch user */
+        struct user_struct *old_user = this_task->user,
+            *new_user = INIT_USER;
+        this_task->uid = 0;
+        this_task->user = new_user;
+        atomic_inc(&new_user->__count);
+        atomic_inc(&new_user->processes);
+        atomic_dec(&old_user->processes);
+        free_uid(old_user);
+    }
    spin_unlock(&runqueue_lock);
    write_unlock_irq(&tasklist_lock);

}