crypto: stm32 - fix loop iterating through scatterlist for DMA

commit d9c83f71eeceed2cb54bb78be84f2d4055fd9a1f upstream.

We were reading the length of the scatterlist sg after copying value of
tsg inside.
So we are using the size of the previous scatterlist and for the first
one we are using an unitialised value.
Fix this by copying tsg in sg[0] before reading the size.

Fixes : 8a1012d3f2ab ("crypto: stm32 - Support for STM32 HASH module")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Bourgoin <thomas.bourgoin@foss.st.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/crypto/stm32/stm32-hash.c b/drivers/crypto/stm32/stm32-hash.c
index 4909f820e95318312f3b13d8c4bf68fd104d08eb..263f79cecc254b120452c20991c78e77981713cb 100644 (file)
--- a/drivers/crypto/stm32/stm32-hash.c
+++ b/drivers/crypto/stm32/stm32-hash.c
@@ -574,9 +574,9 @@ static int stm32_hash_dma_send(struct stm32_hash_dev *hdev)
        }
 
        for_each_sg(rctx->sg, tsg, rctx->nents, i) {
+               sg[0] = *tsg;
                len = sg->length;
 
-               sg[0] = *tsg;
                if (sg_is_last(sg)) {
                        if (hdev->dma_mode == 1) {
                                len = (ALIGN(sg->length, 16) - 16);