[RFC][PATCH 1/2] Deny CLONE_PARENT|CLONE_NEWPID combination

[Sukadev Bhattiprolu <sukadev-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>]

Deny CLONE_PARENT|CLONE_NEWPID combination.

CLONE_PARENT was probably used to implement an older threading model.
If so, for consistency with CLONE_THREAD, the CLONE_PARENT|CLONE_NEWPID
combination should also fail with -EINVAL.

Signed-off-by: Sukadev Bhattiprolu <sukadev-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
---
 kernel/pid_namespace.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-mmotm/kernel/pid_namespace.c
===================================================================
--- linux-mmotm.orig/kernel/pid_namespace.c	2009-06-17 18:19:42.000000000 -0700
+++ linux-mmotm/kernel/pid_namespace.c	2009-06-17 18:19:58.000000000 -0700
@@ -118,7 +118,7 @@ struct pid_namespace *copy_pid_ns(unsign
 {
 	if (!(flags & CLONE_NEWPID))
 		return get_pid_ns(old_ns);
-	if (flags & CLONE_THREAD)
+	if (flags & (CLONE_THREAD|CLONE_PARENT))
 		return ERR_PTR(-EINVAL);
 	return create_pid_namespace(old_ns);
 }