From: Radhey Shyam Pandey radhey.shyam.pandey@xilinx.com
[ Upstream commit f9a9f43a62a04ec3183fb0da9226c7706eed0115 ]
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@xilinx.com Link: https://lore.kernel.org/r/1652166762-18317-2-git-send-email-radhey.shyam.pan... Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 84009c5e0f33..b61d0c79dffb 100644 --- a/drivers/dma/xilinx/zynqmp_dma.c +++ b/drivers/dma/xilinx/zynqmp_dma.c @@ -232,7 +232,7 @@ 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; @@ -489,7 +489,8 @@ 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;