From: Dr. Stephen Henson <steve@openssl.org>
Date: Wed, 22 Jun 2011 15:23:20 +0000 (+0000)
Subject: PR: 2540
X-Git-Tag: OpenSSL_0_9_8s~48
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=22152d6885fac98777ae1d7626a78c20b1ab4295;p=oweals%2Fopenssl.git

PR: 2540
Submitted by: emmanuel.azencot@bull.net
Reviewed by: steve

Prevent infinite loop in BN_GF2m_mod_inv().
---

diff --git a/crypto/bn/bn_gf2m.c b/crypto/bn/bn_gf2m.c
index ae642ccb39..5d90f1e88b 100644
--- a/crypto/bn/bn_gf2m.c
+++ b/crypto/bn/bn_gf2m.c
@@ -607,6 +607,7 @@ int BN_GF2m_mod_inv(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx)
 		{
 		while (!BN_is_odd(u))
 			{
+			if (BN_is_zero(u)) goto err;
 			if (!BN_rshift1(u, u)) goto err;
 			if (BN_is_odd(b))
 				{