[PATCH] udmabuf: fix error code in map_udmabuf()

[Dan Carpenter]

We accidentally forgot to set "ret" on this error path so it means we
return NULL instead of an error pointer.  The caller checks for NULL and
changes it to an error pointer so it doesn't cause an issue at run time.

Signed-off-by: Dan Carpenter <dan.carpenter at oracle.com>

diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c
index 9edabce0b8ab..5b44ef226904 100644
--- a/drivers/dma-buf/udmabuf.c
+++ b/drivers/dma-buf/udmabuf.c
@@ -61,8 +61,10 @@ static struct sg_table *map_udmabuf(struct dma_buf_attachment *at,
 					GFP_KERNEL);
 	if (ret < 0)
 		goto err;
-	if (!dma_map_sg(at->dev, sg->sgl, sg->nents, direction))
+	if (!dma_map_sg(at->dev, sg->sgl, sg->nents, direction)) {
+		ret = -EINVAL;
 		goto err;
+	}
 	return sg;
 
 err: