[PATCH] NUMA x86: add constraints check for nid parameters in numa.c functions

[Petr Holasek <pholasek@redhat.com>]

This patch adds constraints checks into __node_distance() and
numa_set_distance() functions. If from or to parameters are
lower than zero, it results into oops now.

Signed-off-by: Petr Holasek <pholasek@redhat.com>
---
 arch/x86/mm/numa.c |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index fbeaaf4..0f98356 100644
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c
@@ -439,6 +439,12 @@ void __init numa_set_distance(int from, int to, int distance)
 	if (!numa_distance && numa_alloc_distance() < 0)
 		return;
 
+	if (from < 0 || to < 0) {
+		pr_warn_once("NUMA: Warning: invalid from/to nid parameter, from=%d to=%d distance=%d\n",
+				from, to, distance);
+		return;
+	}
+
 	if (from >= numa_distance_cnt || to >= numa_distance_cnt) {
 		printk_once(KERN_DEBUG "NUMA: Debug: distance out of bound, from=%d to=%d distance=%d\n",
 			    from, to, distance);
@@ -457,7 +463,7 @@ void __init numa_set_distance(int from, int to, int distance)
 
 int __node_distance(int from, int to)
 {
-	if (from >= numa_distance_cnt || to >= numa_distance_cnt)
+	if (from < 0 || to < 0 || from >= numa_distance_cnt || to >= numa_distance_cnt)
 		return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
 	return numa_distance[from * numa_distance_cnt + to];
 }
-- 
1.7.6.4