From: Corentin Labbe <clabbe.montjoie@xxxxxxxxx> [ Upstream commit f87391558acf816b48f325a493d81d45dec40da0 ] When nbytes < 4, end is wronlgy set to a negative value which, due to uint, is then interpreted to a large value leading to a deadlock in the following code. This patch fix this problem. Fixes: 6298e948215f ("crypto: sunxi-ss - Add Allwinner Security System crypto accelerator") Signed-off-by: Corentin Labbe <clabbe.montjoie@xxxxxxxxx> Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/crypto/sunxi-ss/sun4i-ss-hash.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/crypto/sunxi-ss/sun4i-ss-hash.c b/drivers/crypto/sunxi-ss/sun4i-ss-hash.c index 0de2f62d51ff7..ec16ec2e284d0 100644 --- a/drivers/crypto/sunxi-ss/sun4i-ss-hash.c +++ b/drivers/crypto/sunxi-ss/sun4i-ss-hash.c @@ -250,7 +250,10 @@ static int sun4i_hash(struct ahash_request *areq) } } else { /* Since we have the flag final, we can go up to modulo 4 */ - end = ((areq->nbytes + op->len) / 4) * 4 - op->len; + if (areq->nbytes < 4) + end = 0; + else + end = ((areq->nbytes + op->len) / 4) * 4 - op->len; } /* TODO if SGlen % 4 and op->len == 0 then DMA */ -- 2.20.1