diff mbox series

[v4] dma-buf: system_heap: Add a size check for allocation

Message ID 20220120033450.90164-1-guangming.cao@mediatek.com
State New
Headers show
Series [v4] dma-buf: system_heap: Add a size check for allocation | expand

Commit Message

guangming.cao@mediatek.com Jan. 20, 2022, 3:34 a.m. UTC 
From: Guangming <Guangming.Cao@mediatek.com>

Add a size check for allocation since the allocation size should be
always less than the total DRAM size on system heap.
And it can prevent consuming too much time for invalid allocations.

Signed-off-by: Guangming <Guangming.Cao@mediatek.com>
---
 drivers/dma-buf/heaps/system_heap.c | 7 +++++++
 1 file changed, 7 insertions(+)
diff mbox series

Patch

diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c
index 23a7e74ef966..bd6f255620e2 100644
--- a/drivers/dma-buf/heaps/system_heap.c
+++ b/drivers/dma-buf/heaps/system_heap.c
@@ -347,6 +347,13 @@  static struct dma_buf *system_heap_allocate(struct dma_heap *heap,
 	struct page *page, *tmp_page;
 	int i, ret = -ENOMEM;
 
+	/*
+	 * Size check. The "len" should be less than totalram since system_heap
+	 * memory is comes from system. Adding check here can prevent consuming
+	 * too much time for invalid allocations.
+	 */
+	if (len >> PAGE_SHIFT > totalram_pages())
+		return -EINVAL;
 	buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
 	if (!buffer)
 		return ERR_PTR(-ENOMEM);