[PATCH] crypto: mxs-dcp - fix source scatterlist length access

From: Thorsten Blum

Date: Sun Jun 21 2026 - 15:26:51 EST


mxs_dcp_aes_block_crypt() uses sg_dma_len() without mapping the source
scatterlist with dma_map_sg() first. Therefore, sg_dma_len() is invalid
and could return zero or a stale DMA length, causing encryption and
decryption to process the wrong number of bytes when
CONFIG_NEED_SG_DMA_LENGTH=y.

Use the original scatterlist length instead.

Fixes: 15b59e7c3733 ("crypto: mxs - Add Freescale MXS DCP driver")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Thorsten Blum <thorsten.blum@xxxxxxxxx>
---
drivers/crypto/mxs-dcp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/crypto/mxs-dcp.c b/drivers/crypto/mxs-dcp.c
index 133ebc998236..595b2fd84667 100644
--- a/drivers/crypto/mxs-dcp.c
+++ b/drivers/crypto/mxs-dcp.c
@@ -353,7 +353,7 @@ static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)

for_each_sg(req->src, src, sg_nents(req->src), i) {
src_buf = sg_virt(src);
- len = sg_dma_len(src);
+ len = src->length;
tlen += len;
limit_hit = tlen > req->cryptlen;