From: Ming Ma Subject: [PATCH 1/1] crypto: If two strings are exact match, they must have same length. Date: Tue, 21 Mar 2017 16:40:40 -0500 Message-ID: <1490132440-112761-1-git-send-email-mingma@micron.com> Mime-Version: 1.0 Content-Type: text/plain Cc: , , Ming Ma To: , Return-path: Received: from mailout.micron.com ([137.201.242.129]:38222 "EHLO mailout.micron.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758281AbdCUVlW (ORCPT ); Tue, 21 Mar 2017 17:41:22 -0400 Sender: linux-crypto-owner@vger.kernel.org List-ID: When both "crct10dif-pclmul" algorithm and "crct10dif-generic" algorithm exist in crypto_alg_list, "crct10dif-pclmul" should be selected, since it has higher priority than "crct10dif-generic". However, both algorithms have the same cra_name "crct10dif". If we use "crct10dif" to find a matched algorithm in crypto_alg_list, it's possible "crct10dif-generic" is selected, because the code calls strcmp to decide if two string are exact match, but doesn't check if two strings have the same length. exact = !strcmp(q->cra_driver_name, name); So ,if "crct10dif-generic" is in front of "crct10dif-pclmul" in crypto_alg_list, it will be picked as the matched algorithm, even if it has lower priority than "crct10dif-pclmul". Signed-off-by: Ming Ma --- crypto/api.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/crypto/api.c b/crypto/api.c index b16ce16..5b3d45a 100644 --- a/crypto/api.c +++ b/crypto/api.c @@ -76,7 +76,8 @@ static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type, ((struct crypto_larval *)q)->mask != mask) continue; - exact = !strcmp(q->cra_driver_name, name); + exact = (strlen(name) == strlen(q->cra_driver_name)) && + !strcmp(q->cra_driver_name, name); fuzzy = !strcmp(q->cra_name, name); if (!exact && !(fuzzy && q->cra_priority > best)) continue; -- 2.4.11