[PATCH 5.18 622/879] crypto: sun8i-ss - handle zero sized sg

Greg Kroah-Hartman
2022-06-08T01:29:24Z

From: Corentin Labbe <clabbe@baylibre.com>

[ Upstream commit c149e4763d28bb4c0e5daae8a59f2c74e889f407 ]

sun8i-ss does not handle well the possible zero sized sg.

Fixes: d9b45418a917 ("crypto: sun8i-ss - support hash algorithms")
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c
index 1a71ed49d233..ca4f280af35d 100644
--- a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c
+++ b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c
@@ -380,13 +380,21 @@ int sun8i_ss_hash_run(struct crypto_engine *engine, void *breq)
}

len = areq->nbytes;
- for_each_sg(areq->src, sg, nr_sgs, i) {
+ sg = areq->src;
+ i = 0;
+ while (len > 0 && sg) {
+ if (sg_dma_len(sg) == 0) {
+ sg = sg_next(sg);
+ continue;
+ }
rctx->t_src[i].addr = sg_dma_address(sg);
todo = min(len, sg_dma_len(sg));
rctx->t_src[i].len = todo / 4;
len -= todo;
rctx->t_dst[i].addr = addr_res;
rctx->t_dst[i].len = digestsize / 4;
+ sg = sg_next(sg);
+ i++;
}
if (len > 0) {
dev_err(ss->dev, "remaining len %d\n", len);
--
2.35.1