In zynqmp_dma_alloc/free_chan_resources functions there is a
potential overflow in the below expressions.
dma_alloc_coherent(chan->dev, (2 * chan->desc_size *
ZYNQMP_DMA_NUM_DESCS),
&chan->desc_pool_p, GFP_KERNEL);
dma_free_coherent(chan->dev,(2 * ZYNQMP_DMA_DESC_SIZE(chan) *
ZYNQMP_DMA_NUM_DESCS),
chan->desc_pool_v, chan->desc_pool_p);
The arguments desc_size and ZYNQMP_DMA_NUM_DESCS were 32 bit. Though
this overflow condition is not observed but it is a potential problem
in the case of 32-bit multiplication. Hence fix it by changing the
desc_size data type to size_t.
In addition to coverity fix it also reuse ZYNQMP_DMA_DESC_SIZE macro in
dma_alloc_coherent API argument.
Addresses-Coverity: Event overflow_before_widen.
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxxxxx>
---
drivers/dma/xilinx/zynqmp_dma.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c
index 7aa63b652027..3ffa7f37c701 100644
--- a/drivers/dma/xilinx/zynqmp_dma.c
+++ b/drivers/dma/xilinx/zynqmp_dma.c
@@ -229,7 +229,7 @@ struct zynqmp_dma_chan {
bool is_dmacoherent;
struct tasklet_struct tasklet;
bool idle;
- u32 desc_size;
+ size_t desc_size;
bool err;
u32 bus_width;
u32 src_burst_len;
@@ -486,7 +486,8 @@ static int zynqmp_dma_alloc_chan_resources(struct dma_chan *dchan)
}
chan->desc_pool_v = dma_alloc_coherent(chan->dev,
- (2 * chan->desc_size * ZYNQMP_DMA_NUM_DESCS),
+ (2 * ZYNQMP_DMA_DESC_SIZE(chan) *
+ ZYNQMP_DMA_NUM_DESCS),
&chan->desc_pool_p, GFP_KERNEL);
if (!chan->desc_pool_v)
return -ENOMEM;
--
2.25.1
