Added validity check for count variable, return if count variable does
not meet the execution condition (do not execute mutex_lock and
mutex_unlock function).
Signed-off-by: Li kunyu <kunyu@xxxxxxxxxxxx>
---
drivers/vfio/vfio_iommu_type1.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 23c24fe98c00..9bdf96d932e4 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -3137,6 +3137,9 @@ static int vfio_iommu_type1_dma_rw(void *iommu_data, dma_addr_t user_iova,
int ret = 0;
size_t done;
+ if (count <= 0)
+ return ret;
+
mutex_lock(&iommu->lock);
while (count > 0) {
ret = vfio_iommu_type1_dma_rw_chunk(iommu, user_iova, data,
--
2.18.2
