openvswitch: allocate nr_node_ids flow_stats instead of num_possible_nodes

Chris J Arges · davem330 · commit bac541e46319 · 2015-07-21T22:26:03.000-07:00
Some architectures like POWER can have a NUMA node_possible_map that contains sparse entries. This causes memory corruption with openvswitch since it allocates flow_cache with a multiple of num_possible_nodes() and assumes the node variable returned by for_each_node will index into flow->stats[node]. Use nr_node_ids to allocate a maximal sparse array instead of num_possible_nodes(). The crash was noticed after 3af229f was applied as it changed the node_possible_map to match node_online_map on boot. Fixes: 3af229f Signed-off-by: Chris J Arges <chris.j.arges@canonical.com> Acked-by: Pravin B Shelar <pshelar@nicira.com> Acked-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c
@@ -752,7 +752,7 @@ int ovs_flow_init(void)
 	BUILD_BUG_ON(sizeof(struct sw_flow_key) % sizeof(long));
 
 	flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow)
-				       + (num_possible_nodes()
+				       + (nr_node_ids
 					  * sizeof(struct flow_stats *)),
 				       0, 0, NULL);
 	if (flow_cache == NULL)
