[GEODE-9429] Radish HSCAN implementation cannot handle values for COUNT greater than Integer.MAX_VALUE / 2

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.15.0
• Fix Version/s: 1.15.0
• Component/s: redis
• Labels: pull-request-available unreleased
• Assignee: Donal Evans
• Reporter: Donal Evans
• Created: 13/Jul/21 19:28
• Updated: 22/Jun/22 20:46
• Resolved: 26/Jul/21 16:55

Description

The below code is the current implementation of HSCAN in RedisHash. When the value of count passed to this method is greater than Integer.MAX_VALUE / 2 the condition of the while loop suffers from integer overflow and the loop does not execute correctly.

  public ImmutablePair<Integer, List<byte[]>> hscan(Pattern matchPattern, int count, int cursor) {

    ArrayList<byte[]> resultList = new ArrayList<>(count + 2);
    do {
      cursor = hash.scan(cursor, 1,
          (list, key, value) -> addIfMatching(matchPattern, list, key, value), resultList);
    } while (cursor != 0 && resultList.size() < (count * 2));

    return new ImmutablePair<>(cursor, resultList);

This could be fixed by changing the type of resultList to List<ImmutablePair<byte[] byte[]>> and modifying the addIfMatching() method to populate the list with {{ImmutablePair}}s of keys and values rather than a single continuous list of interleaved keys and values.

Issue Links

• links to: GitHub Pull Request #6701