From: Stefan Berger <stefanb@linux.ibm.com>
Date: Thu, 4 Apr 2024 14:18:52 +0000 (-0400)
Subject: crypto: ecdsa - Replace ndigits with nbits where precision is needed
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=dee45a607abbd52fd572622c281010037a85544b;p=linux.git

crypto: ecdsa - Replace ndigits with nbits where precision is needed

Replace the usage of ndigits with nbits where precise space calculations
are needed, such as in ecdsa_max_size where the length of a coordinate is
determined.

Tested-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---

diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c
index 9b84ab5032762..75d3eea885dbb 100644
--- a/crypto/ecdsa.c
+++ b/crypto/ecdsa.c
@@ -266,7 +266,7 @@ static unsigned int ecdsa_max_size(struct crypto_akcipher *tfm)
 {
 	struct ecc_ctx *ctx = akcipher_tfm_ctx(tfm);
 
-	return ctx->pub_key.ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
+	return DIV_ROUND_UP(ctx->curve->nbits, 8);
 }
 
 static int ecdsa_nist_p384_init_tfm(struct crypto_akcipher *tfm)