commit 966e72b82216ce866d1d4203c3e121a656ceee87
author Kweku Adams <kwekua@google.com> Thu May 30 14:45:39 2019 -0700
committer Kweku Adams <kwekua@google.com> Fri May 31 10:57:48 2019 -0700
tree 32aa7e0db41ac48defd46a8f36c5316ee321d7dc
parent 2e45d4fb47f781680cb8d26a65e5556b56b94f72

Adding checks for bad periodic job scheduling.

1. There are cases where a periodic job is scheduled in a past time
period. Without any other constraints, the job could be run much too
frequently and spam the system. Adding these checks makes sure the jobs
are scheduled with sane values.
2. Adding an upper limit on the job period to avoid overflow cases.
3. Changing int to long to avoid overflow.

Bug: 133654009
Test: atest com.android.server.job.JobSchedulerServiceTest
Test: atest com.android.server.job.controllers.QuotaControllerTest
Test: atest com.android.server.job.controllers.TimeControllerTest
Test: atest CtsJobSchedulerTestCases
Change-Id: I97616efb6c37b7201eb926d16c0d9be450bf2ba4

services/core/java/com/android/server/job/controllers/JobStatus.java

diff --git a/services/core/java/com/android/server/job/controllers/JobStatus.java b/services/core/java/com/android/server/job/controllers/JobStatus.java
index fd20e11..eb5d472 100644
--- a/services/core/java/com/android/server/job/controllers/JobStatus.java
+++ b/services/core/java/com/android/server/job/controllers/JobStatus.java
@@ -511,8 +511,13 @@
         final long elapsedNow = sElapsedRealtimeClock.millis();
         final long earliestRunTimeElapsedMillis, latestRunTimeElapsedMillis;
         if (job.isPeriodic()) {
-            latestRunTimeElapsedMillis = elapsedNow + job.getIntervalMillis();
-            earliestRunTimeElapsedMillis = latestRunTimeElapsedMillis - job.getFlexMillis();
+            // Make sure period is in the interval [min_possible_period, max_possible_period].
+            final long period = Math.max(JobInfo.getMinPeriodMillis(),
+                    Math.min(JobSchedulerService.MAX_ALLOWED_PERIOD_MS, job.getIntervalMillis()));
+            latestRunTimeElapsedMillis = elapsedNow + period;
+            earliestRunTimeElapsedMillis = latestRunTimeElapsedMillis
+                    // Make sure flex is in the interval [min_possible_flex, period].
+                    - Math.max(JobInfo.getMinFlexMillis(), Math.min(period, job.getFlexMillis()));
         } else {
             earliestRunTimeElapsedMillis = job.hasEarlyConstraint() ?
                     elapsedNow + job.getMinLatencyMillis() : NO_EARLIEST_RUNTIME;
@@ -1631,6 +1636,9 @@
         formatRunTime(pw, earliestRunTimeElapsedMillis, NO_EARLIEST_RUNTIME, elapsedRealtimeMillis);
         pw.print(", latest=");
         formatRunTime(pw, latestRunTimeElapsedMillis, NO_LATEST_RUNTIME, elapsedRealtimeMillis);
+        pw.print(", original latest=");
+        formatRunTime(pw, mOriginalLatestRunTimeElapsedMillis,
+                NO_LATEST_RUNTIME, elapsedRealtimeMillis);
         pw.println();
         if (numFailures != 0) {
             pw.print(prefix); pw.print("Num failures: "); pw.println(numFailures);