From 8f493d797bc1fe470377adc9d8775845427e240e Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 3 Jan 2006 00:07:28 +0100 Subject: [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 Signed-off-by: Linus Torvalds --- mm/mempolicy.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index bec88c8..72f402c 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -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); -- cgit v1.1