[PATCH] Make sure interleave masks have at least one node set

Otherwise a bad mem policy system call can confuse the interleaving
code into referencing undefined nodes.

Originally reported by Doug Chapman

I was told it's CVE-2005-3358
(one has to love these security people - they make everything sound important)

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Andi Kleen 2006-01-03 00:07:28 +01:00 committed by Linus Torvalds
parent abe842eb98
commit 8f493d797b

View File

@ -161,6 +161,10 @@ static struct mempolicy *mpol_new(int mode, nodemask_t *nodes)
switch (mode) {
case MPOL_INTERLEAVE:
policy->v.nodes = *nodes;
if (nodes_weight(*nodes) == 0) {
kmem_cache_free(policy_cache, policy);
return ERR_PTR(-EINVAL);
}
break;
case MPOL_PREFERRED:
policy->v.preferred_node = first_node(*nodes);