From: Bernd Edlinger <bernd.edlinger@hotmail.de>
Date: Tue, 13 Jun 2017 20:08:03 +0000 (+0200)
Subject: Fix another possible crash in rsa_ossl_mod_exp.
X-Git-Tag: OpenSSL_1_1_0g~173
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=ded1b50f83c4d0d3e12a2a64d3bd66a27884136e;p=oweals%2Fopenssl.git

Fix another possible crash in rsa_ossl_mod_exp.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3675)
(cherry picked from commit 5625567f9c7daaa2e2689647e10e4c5d7370718f)
---

diff --git a/crypto/rsa/rsa_ossl.c b/crypto/rsa/rsa_ossl.c
index 793e2f9c87..62a88959fa 100644
--- a/crypto/rsa/rsa_ossl.c
+++ b/crypto/rsa/rsa_ossl.c
@@ -603,6 +603,8 @@ static int rsa_ossl_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
     r1 = BN_CTX_get(ctx);
     m1 = BN_CTX_get(ctx);
     vrfy = BN_CTX_get(ctx);
+    if (vrfy == NULL)
+        goto err;
 
     {
         BIGNUM *p = BN_new(), *q = BN_new();