From: Volker Lendecke <vl@samba.org>
Date: Tue, 21 Jul 2026 10:38:17 +0000 (+0200)
Subject: lib: Make signed/unsigned conversion explicit in asn1_peek()
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=16e4e8a9c7470cb31216204c2f57551d8dbd93d2;p=thirdparty%2Fsamba.git

lib: Make signed/unsigned conversion explicit in asn1_peek()

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Anoop C S <anoopcs@samba.org>
---

diff --git a/lib/util/asn1.c b/lib/util/asn1.c
index 6fb4d9ea812..64ee4e9e0c9 100644
--- a/lib/util/asn1.c
+++ b/lib/util/asn1.c
@@ -524,13 +524,27 @@ bool asn1_load(struct asn1_data *data, DATA_BLOB blob)
 /* Peek into an ASN1 buffer, not advancing the pointer */
 bool asn1_peek(struct asn1_data *data, void *p, int len)
 {
+	size_t ofs, end;
+
 	if (data->has_error)
 		return false;
 
-	if (len < 0 || data->ofs + len < data->ofs || data->ofs + len < len)
+	if (len < 0) {
+		return false;
+	}
+
+	if (data->ofs < 0) {
+		data->has_error = true;
+		return false;
+	}
+	ofs = data->ofs;
+
+	end = ofs + len;
+	if (end < ofs) {
 		return false;
+	}
 
-	if (data->ofs + len > data->length) {
+	if (end > data->length) {
 		/* we need to mark the buffer as consumed, so the caller knows
 		   this was an out of data error, and not a decode error */
 		data->ofs = data->length;