inherit HMAC flags from MD_CTX

crypto/hmac/hm_pmeth.c

@@ -149,6 +149,8 @@ static int int_update(EVP_MD_CTX *ctx,const void *data,size_t count)
 
 static int hmac_signctx_init(EVP_PKEY_CTX *ctx, EVP_MD_CTX *mctx)
 	{
+	HMAC_PKEY_CTX *hctx = ctx->data;
+	HMAC_CTX_set_flags(&hctx->ctx, mctx->flags & ~EVP_MD_CTX_FLAG_NO_INIT);
 	EVP_MD_CTX_set_flags(mctx, EVP_MD_CTX_FLAG_NO_INIT);
 	mctx->update = int_update;
 	return 1;