lib: Make signed/unsigned conversion explicit in asn1_write()

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 fa90442f0b9d2ce69200da0811fd9dc7c76d2cc1..6fb4d9ea812fe40a551f9a50d7726346b1a5b912 100644 (file)
--- a/lib/util/asn1.c
+++ b/lib/util/asn1.c
@@ -80,22 +80,35 @@ off_t asn1_current_ofs(const struct asn1_data *data)
 }
 
 /* write to the ASN1 buffer, advancing the buffer pointer */
-bool asn1_write(struct asn1_data *data, const void *p, int len)
+bool asn1_write(struct asn1_data *data, const void *p, int _len)
 {
+       size_t len, ofs, newlen;
+
        if (data->has_error) return false;
 
-       if ((len < 0) || (data->ofs + (size_t)len < data->ofs)) {
+       if (_len < 0) {
+               goto error;
+       }
+       len = _len;
+
+       if (data->ofs < 0) {
+               goto error;
+       }
+       ofs = data->ofs;
+
+       newlen = ofs + len;
+       if (newlen < ofs) {
                goto error;
        }
 
-       if (data->length < data->ofs+len) {
+       if (data->length < newlen) {
                uint8_t *newp;
-               newp = talloc_realloc(data, data->data, uint8_t, data->ofs+len);
+               newp = talloc_realloc(data, data->data, uint8_t, newlen);
                if (!newp) {
                        goto error;
                }
                data->data = newp;
-               data->length = data->ofs+len;
+               data->length = newlen;
        }
        if (len > 0) {
                memcpy(data->data + data->ofs, p, len);