diff -up openssl-1.0.2k/crypto/dh/dh_key.c.large-dh openssl-1.0.2k/crypto/dh/dh_key.c

--- openssl-1.0.2k/crypto/dh/dh_key.c.large-dh	2018-06-18 13:46:24.268137362 +0200

+++ openssl-1.0.2k/crypto/dh/dh_key.c	2018-06-18 13:59:04.605497462 +0200

@@ -133,7 +133,7 @@ static int generate_key(DH *dh)

     int ok = 0;

     int generate_new_key = 0;

     unsigned l;

-    BN_CTX *ctx;

+    BN_CTX *ctx = NULL;

     BN_MONT_CTX *mont = NULL;

     BIGNUM *pub_key = NULL, *priv_key = NULL;

@@ -145,6 +145,11 @@ static int generate_key(DH *dh)

     }

 #endif

+    if (BN_num_bits(dh->p) > OPENSSL_DH_MAX_MODULUS_BITS) {

+        DHerr(DH_F_GENERATE_KEY, DH_R_MODULUS_TOO_LARGE);

+        return 0;

+    }

+

     ctx = BN_CTX_new();

     if (ctx == NULL)

         goto err;