diff --git a/crypto/dh.c b/crypto/dh.c
index 9d19360..df7698e 100644
--- a/crypto/dh.c
+++ b/crypto/dh.c
@@ -84,6 +84,9 @@
 	struct dh_ctx *ctx = dh_get_ctx(tfm);
 	struct dh params;
 
+	/* Free the old MPI key if any */
+	dh_free_ctx(ctx);
+
 	if (crypto_dh_decode_key(buf, len, &params) < 0)
 		return -EINVAL;