From e497a8f5898158969989e91cefd1eb48703e93ac Mon Sep 17 00:00:00 2001
From: Jacob Barthelmeh <jacob@wolfssl.com>
Date: Sat, 6 Mar 2021 08:58:37 +0700
Subject: [PATCH] sanity check on size before compare

---
 wolfcrypt/src/pkcs7.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/wolfcrypt/src/pkcs7.c b/wolfcrypt/src/pkcs7.c
index 2e93f4b58..90c740e8e 100644
--- a/wolfcrypt/src/pkcs7.c
+++ b/wolfcrypt/src/pkcs7.c
@@ -8423,6 +8423,9 @@ static int wc_PKCS7_DecryptKtri(PKCS7* pkcs7, byte* in, word32 inSz,
                 if (GetLength(pkiMsg, idx, &length, pkiMsgSz) < 0)
                     return ASN_PARSE_E;
 
+                if (KEYID_SIZE > pkiMsgSz - (*idx))
+                    return BUFFER_E;
+
                 /* if we found correct recipient, SKID will match */
                 if (XMEMCMP(pkiMsg + (*idx), pkcs7->issuerSubjKeyId,
                             KEYID_SIZE) == 0) {