Check the return of EVP_KDF_fetch()
@@ -39,6 +39,8 @@ int ossl_dh_kdf_X9_42_asn1(unsigned char *out, size_t outlen,
const char *mdname = EVP_MD_get0_name(md);
kdf = EVP_KDF_fetch(libctx, OSSL_KDF_NAME_X942KDF_ASN1, propq);
+ if (kdf == NULL)
+ return 0;
kctx = EVP_KDF_CTX_new(kdf);
if (kctx == NULL)
goto err;
