[PATCH v2 4/4] staging: android: Add error handling to order_to_index callers

[Tomer Samara]

Add error check to:
- free_buffer_page
- alloc_buffer_page
after calling order_to_index, due to converting BUG to WARN at
order_to_index.

Signed-off-by: Tomer Samara <tomersamara98 at gmail.com>
---
 drivers/staging/android/ion/ion_system_heap.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/android/ion/ion_system_heap.c b/drivers/staging/android/ion/ion_system_heap.c
index 37065a59ca69..1e73bfc88884 100644
--- a/drivers/staging/android/ion/ion_system_heap.c
+++ b/drivers/staging/android/ion/ion_system_heap.c
@@ -49,8 +49,13 @@ static struct page *alloc_buffer_page(struct ion_system_heap *heap,
 				      struct ion_buffer *buffer,
 				      unsigned long order)
 {
-	struct ion_page_pool *pool = heap->pools[order_to_index(order)];
+	struct ion_page_pool *pool;
+	int index = order_to_index(order);
+
+	if (index < 0)
+		return NULL;
 
+	pool = heap->pools[index];
 	return ion_page_pool_alloc(pool);
 }
 
@@ -59,6 +64,7 @@ static void free_buffer_page(struct ion_system_heap *heap,
 {
 	struct ion_page_pool *pool;
 	unsigned int order = compound_order(page);
+	int index;
 
 	/* go to system */
 	if (buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE) {
@@ -66,8 +72,11 @@ static void free_buffer_page(struct ion_system_heap *heap,
 		return;
 	}
 
-	pool = heap->pools[order_to_index(order)];
+	index = order_to_index(order);
+	if (index < 0)
+		return;
 
+	pool = heap->pools[index];
 	ion_page_pool_free(pool, page);
 }
 
-- 
2.25.1