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> --- 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 a4b5ff2b72f8..f6936bb3b7be 100644 --- a/drivers/crypto/sunxi-ss/sun4i-ss-hash.c +++ b/drivers/crypto/sunxi-ss/sun4i-ss-hash.c @@ -240,7 +240,10 @@ 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 then DMA */ -- 2.21.0