- php_http_buffer_appendf(&neon->options.headers, "Range: bytes=%.*s" PHP_HTTP_CRLF, rs.used - 1, rs.data);
+ int used = rs.used > INT_MAX ? INT_MAX : rs.used;
+ php_http_buffer_appendf(&neon->options.headers, "Range: bytes=%.*s" PHP_HTTP_CRLF, used - 1, rs.data);