[PATCH v2 4/7] crypto: stm32 - fix loop iterating through scatterlist for DMA

[Thomas BOURGOIN]

From: Thomas Bourgoin <thomas.bourgoin@xxxxxxxxxxx>

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@xxxxxxxxxxxxxxx
Signed-off-by: Thomas Bourgoin <thomas.bourgoin@xxxxxxxxxxx>

---
Changes in v2:
 - Add Fixes 8a1012d3f2ab ("crypto: stm32 - Support for STM32 HASH module")
 - Add Cc: stable@xxxxxxxxxxxxxxx

 drivers/crypto/stm32/stm32-hash.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/crypto/stm32/stm32-hash.c b/drivers/crypto/stm32/stm32-hash.c
index c179a6c1a457..519fb716acee 100644
--- a/drivers/crypto/stm32/stm32-hash.c
+++ b/drivers/crypto/stm32/stm32-hash.c
@@ -678,9 +678,9 @@ 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);
-- 
2.25.1