[webkit-changes] [WebKit/WebKit] 99bbc3: Race condition in report-processor between fetchin...

[dewei-zhu]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 99bbc3cc4b9e93b97035efcbd980245652de5223
      https://github.com/WebKit/WebKit/commit/99bbc3cc4b9e93b97035efcbd980245652de5223
  Author: Dewei Zhu <dewei_zhu at apple.com>
  Date:   2024-07-09 (Tue, 09 Jul 2024)

  Changed paths:
    M Websites/perf.webkit.org/public/include/report-processor.php

  Log Message:
  -----------
  Race condition in report-processor between fetching `tests` and `test_metrics` tables
rdar://131324950
https://bugs.webkit.org/show_bug.cgi?id=276330

Reviewed by Ryosuke Niwa.

The race condition is caused by `tests` and `test_metrics` not being fetched atomically.
New `tests` and `test_metrics` entries can be inserted by another concurrent call after `tests` table
fetch but before `test_metrics` fetch. `test_metrics` can refer to a new test and cause null reference
in the array key by test id.
The fix is to ignore new `test_metrics` based on following observation:
    1. `ReportProcessor->fetch_tests` builds `ReportProcessor->tests` variable which is only used by
       `ReportProcessor->recursively_ensure_tests`.
    2. `ReportProcessor->recursively_ensure_tests` handles missing tests / metrics by fetching them
       from database.

* Websites/perf.webkit.org/public/include/report-processor.php: Add a null check on `$test['metrics']`.

Canonical link: https://commits.webkit.org/280784@main



To unsubscribe from these emails, change your notification settings at https://github.com/WebKit/WebKit/settings/notifications