udev: specify the end of value

NULSTR_FOREACH may read the illegal match

Signed-off-by: gaoyi <ymuemc@163.com>

src/udev/udev-rules.c

@@ -452,6 +452,11 @@ static int rule_line_add_token(UdevRuleLine *rule_line, UdevRuleTokenType type,
                                 }
                         }
                         *b = '\0';
+
+                        /* Make sure the value is end, so NULSTR_FOREACH can read correct match */
+                        if (b < a)
+                                b[1] = '\0';
+
                         if (bar)
                                 empty = true;