From 263fdc6b067bd892df654377c0ea051289fce33f Mon Sep 17 00:00:00 2001
From: "Todd C. Miller" <Todd.Miller@sudo.ws>
Date: Mon, 6 Jun 2022 20:15:03 -0600
Subject: [PATCH] Fix issue protobuf-c#499: unsigned integer overflow
 Signed-off-by: 10054172 <hui.zhang@thalesgroup.com>

---
 lib/protobuf-c/protobuf-c.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/lib/protobuf-c/protobuf-c.c b/lib/protobuf-c/protobuf-c.c
index 96b750650..73e120046 100644
--- a/lib/protobuf-c/protobuf-c.c
+++ b/lib/protobuf-c/protobuf-c.c
@@ -2619,11 +2619,14 @@ parse_required_member(ScannedMember *scanned_member,
 			return FALSE;
 
 		def_mess = scanned_member->field->default_value;
-		subm = protobuf_c_message_unpack(scanned_member->field->descriptor,
-						 allocator,
-						 len - pref_len,
-						 data + pref_len);
-
+		if (len > pref_len) {
+			subm = protobuf_c_message_unpack(scanned_member->field->descriptor,
+							 allocator,
+							 len - pref_len,
+							 data + pref_len);
+		} else {
+			subm = NULL;
+		}
 		if (maybe_clear &&
 		    *pmessage != NULL &&
 		    *pmessage != def_mess)
-- 
2.33.0

