From: Philippe Antoine <pantoine@oisf.net>
Date: Wed, 2 Oct 2024 18:39:26 +0000 (+0200)
Subject: transform/base64: check for 0-sized buffer
X-Git-Tag: suricata-8.0.0-beta1~820
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=40e97423b4caca909b4bc4423b87abb1753962d1;p=thirdparty%2Fsuricata.git

transform/base64: check for 0-sized buffer

So as to avoid undefined behavior with a 0-sized variable length
array

Ticket: #7296
---

diff --git a/src/detect-transform-base64.c b/src/detect-transform-base64.c
index f8d8f6e241..e0fbdeeb44 100644
--- a/src/detect-transform-base64.c
+++ b/src/detect-transform-base64.c
@@ -141,6 +141,9 @@ static void TransformFromBase64Decode(InspectionBuffer *buffer, void *options)
         }
         decode_length = nbytes;
     }
+    if (decode_length == 0) {
+        return;
+    }
 
     uint32_t decoded_size = Base64DecodeBufferSize(decode_length);
     uint8_t decoded[decoded_size];