The result of gx modulo p is zero if gx is equal to p, so return error immediately if gx is equal to p. Signed-off-by: Hui Tang <tanghui20@xxxxxxxxxx> --- drivers/crypto/hisilicon/hpre/hpre_crypto.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/crypto/hisilicon/hpre/hpre_crypto.c b/drivers/crypto/hisilicon/hpre/hpre_crypto.c index 6ba5d8a..323418b 100644 --- a/drivers/crypto/hisilicon/hpre/hpre_crypto.c +++ b/drivers/crypto/hisilicon/hpre/hpre_crypto.c @@ -1841,8 +1841,12 @@ static int hpre_curve25519_src_init(struct hpre_asym_request *hpre_req, * When src_data equals (2^255 - 19) ~ (2^255 - 1), it is out of p, * we get its modulus to p, and then use it. */ - if (memcmp(ptr, p, ctx->key_sz) >= 0) + if (memcmp(ptr, p, ctx->key_sz) == 0) { + dev_err(dev, "gx is p!\n"); + return -EINVAL; + } else if (memcmp(ptr, p, ctx->key_sz) > 0) { hpre_curve25519_src_modulo_p(ptr); + } hpre_req->src = ptr; msg->in = cpu_to_le64(dma); -- 2.8.1