[PATCH 1/1] dmaengine: qcom: Fix possible memory leak

From: Zhen Lei
Date: Thu Jun 17 2021 - 04:21:27 EST

When krealloc() fails to expand the memory and returns NULL, the original
memory is not released. In addition, subsequent memcpy() operation will
overwrite the entire valid memory space, so using krealloc() to preserve
the old content is not necessary.

Change to release the old memory and then apply for new memory.

Fixes: 5d0c3533a19f ("dmaengine: qcom: Add GPI dma driver")
Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
drivers/dma/qcom/gpi.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/qcom/gpi.c b/drivers/dma/qcom/gpi.c
index 43ac3ab23d4c..e24fe64f3b63 100644
--- a/drivers/dma/qcom/gpi.c
+++ b/drivers/dma/qcom/gpi.c
@@ -1625,7 +1625,8 @@ gpi_peripheral_config(struct dma_chan *chan, struct dma_slave_config *config)
if (!config->peripheral_config)
return -EINVAL;

- gchan->config = krealloc(gchan->config, config->peripheral_size, GFP_NOWAIT);
+ kfree(gchan->config);
+ gchan->config = kmalloc(config->peripheral_size, GFP_NOWAIT);
if (!gchan->config)
return -ENOMEM;