Colord: Slow rejection of oversized malformed color strings
colord's CSS color string matchers described a number as ([+-]?\d*.?\d+). In that form \d* and \d+ can match the same digits, so a run of n digits can be divided between them in O(n²) ways, and rejecting an input retries every division. Parsing is synchronous and uninterruptible, so a long malformed color string blocks the thread: | input | time to reject | | — | — | | 16 …