Don't use more memory groups than declared
The number of usable memory groups is limited by the constant limit
MEMORY_GROUP_MANAGER_NR_GROUPS but also by the number of groups actually
declared. Check both limits during allocation.
Bug: 201677538
Signed-off-by: Sean Callanan <spyffe@google.com>
Change-Id: Id23264452a8472e7589ffce3c6bc87cf0552ca32
diff --git a/mali_pixel/memory_group_manager.c b/mali_pixel/memory_group_manager.c
index d057148..5c98a5d 100644
--- a/mali_pixel/memory_group_manager.c
+++ b/mali_pixel/memory_group_manager.c
@@ -94,6 +94,7 @@
* struct mgm_groups - Structure for groups of memory group manager
*
* @groups: To keep track of the number of allocated pages of all groups
+ * @ngroups: Number of groups actually used
* @dev: device attached
* @pt_handle: Link to SLC partition data
* @kobj: &sruct kobject used for linking to pixel_stats_sysfs node
@@ -104,6 +105,7 @@
*/
struct mgm_groups {
struct mgm_group groups[MEMORY_GROUP_MANAGER_NR_GROUPS];
+ size_t ngroups;
struct device *dev;
struct pt_handle *pt_handle;
struct kobject kobj;
@@ -397,6 +399,10 @@
if (INVALID_GROUP_ID(group_id))
return NULL;
+ if (WARN_ON_ONCE((group_id != MGM_RESERVED_GROUP_ID) &&
+ (GROUP_ID_TO_PT_IDX(group_id) >= data->ngroups)))
+ return NULL;
+
/* We don't expect to be allocting pages into the group used for
* external or imported memory
*/
@@ -596,6 +602,14 @@
{
int i, ret;
+ const int ngroups = of_property_count_strings(mgm_data->dev->of_node, "pt_id");
+ if (WARN_ON(ngroups < 0) ||
+ WARN_ON(ngroups > MEMORY_GROUP_MANAGER_NR_GROUPS)) {
+ mgm_data->ngroups = 0;
+ } else {
+ mgm_data->ngroups = ngroups;
+ }
+
for (i = 0; i < MEMORY_GROUP_MANAGER_NR_GROUPS; i++) {
atomic_set(&mgm_data->groups[i].size, 0);
atomic_set(&mgm_data->groups[i].lp_size, 0);
