From 03967d62f4ebe2b8e6059d4eb2a36f5b9a461cc7 Mon Sep 17 00:00:00 2001
From: Jacob Barthelmeh <jacob@wolfssl.com>
Date: Tue, 3 Sep 2019 10:54:11 -0600
Subject: [PATCH] sanity check on resulting ecc size

---
 wolfcrypt/src/ecc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/wolfcrypt/src/ecc.c b/wolfcrypt/src/ecc.c
index 6eda8490b..60494847d 100644
--- a/wolfcrypt/src/ecc.c
+++ b/wolfcrypt/src/ecc.c
@@ -3592,7 +3592,7 @@ static int wc_ecc_shared_secret_gen_sync(ecc_key* private_key, ecc_point* point,
                                                              private_key->heap);
         if (err == MP_OKAY) {
             x = mp_unsigned_bin_size(curve->prime);
-            if (*outlen < x) {
+            if (*outlen < x || (int)x < mp_unsigned_bin_size(result->x)) {
                 err = BUFFER_E;
             }
         }