DBWithTTLImpl::IsStale overflow when ttl is 15 years (#11279)

Summary:
Fix DBWIthTTLImpl::IsStale overflow

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11279

Reviewed By: cbi42

Differential Revision: D43875039

Pulled By: ajkr

fbshipit-source-id: 3e5feb8c4c4480bf1421b0763ade3d2e459ec028

utilities/ttl/db_ttl_impl.cc

@@ -451,7 +451,11 @@ bool DBWithTTLImpl::IsStale(const Slice& value, int32_t ttl,
   if (!clock->GetCurrentTime(&curtime).ok()) {
     return false;  // Treat the data as fresh if could not get current time
   }
-  int32_t timestamp_value =
+  /* int32_t may overflow when timestamp_value + ttl
+   * for example ttl = 86400 * 365 * 15
+   * convert timestamp_value to int64_t
+   */
+  int64_t timestamp_value =
       DecodeFixed32(value.data() + value.size() - kTSLength);
   return (timestamp_value + ttl) < curtime;
 }

utilities/ttl/ttl_test.cc

@@ -635,6 +635,17 @@ TEST_F(TtlTest, MultiGetTest) {
   CloseTtl();
 }
 
+TEST_F(TtlTest, TtlFiftenYears) {
+  MakeKVMap(kSampleSize_);
+  // 15 year will lead int32_t overflow from now
+  const int kFifteenYearSeconds = 86400 * 365 * 15;
+  OpenTtl(kFifteenYearSeconds);
+  PutValues(0, kSampleSize_, true);
+  // trigger the compaction
+  SleepCompactCheck(1, 0, kSampleSize_);
+  CloseTtl();
+}
+
 TEST_F(TtlTest, ColumnFamiliesTest) {
   DB* db;
   Options options;