HDFS-16272. Fix int overflow in computing safe length during EC block recovery (#3548)

(cherry picked from commit 5337bebcc53a0144311877362787ed9ece0cb118)

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/util/StripedBlockUtil.java

@@ -245,8 +245,7 @@ public class StripedBlockUtil {
     Arrays.sort(cpy);
     // full stripe is a stripe has at least dataBlkNum full cells.
     // lastFullStripeIdx is the index of the last full stripe.
-    int lastFullStripeIdx =
-        (int) (cpy[cpy.length - dataBlkNum] / cellSize);
+    long lastFullStripeIdx = cpy[cpy.length - dataBlkNum] / cellSize;
     return lastFullStripeIdx * stripeSize; // return the safeLength
     // TODO: Include lastFullStripeIdx+1 stripe in safeLength, if there exists
     // such a stripe (and it must be partial).
@@ -271,9 +270,9 @@ public class StripedBlockUtil {
    */
   public static long offsetInBlkToOffsetInBG(int cellSize, int dataBlkNum,
       long offsetInBlk, int idxInBlockGroup) {
-    int cellIdxInBlk = (int) (offsetInBlk / cellSize);
+    long cellIdxInBlk = offsetInBlk / cellSize;
     return cellIdxInBlk * cellSize * dataBlkNum // n full stripes before offset
-        + idxInBlockGroup * cellSize // m full cells before offset
+        + (long)idxInBlockGroup * cellSize // m full cells before offset
         + offsetInBlk % cellSize; // partial cell
   }
 

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestLeaseRecoveryStriped.java

@@ -188,6 +188,24 @@ public class TestLeaseRecoveryStriped {
     }
   }
 
+  @Test
+  public void testSafeLength() {
+    checkSafeLength(0, 0); // Length of: 0
+    checkSafeLength(1024 * 1024, 6291456L); // Length of: 1 MiB
+    checkSafeLength(64 * 1024 * 1024, 402653184L); // Length of: 64 MiB
+    checkSafeLength(189729792, 1132462080L); // Length of: 189729792
+    checkSafeLength(256 * 1024 * 1024, 1610612736L); // Length of: 256 MiB
+    checkSafeLength(517399040, 3101687808L); // Length of: 517399040
+    checkSafeLength(1024 * 1024 * 1024, 6442450944L); // Length of: 1 GiB
+  }
+
+  private void checkSafeLength(int blockLength, long expectedSafeLength) {
+    int[] blockLengths = new int[]{blockLength, blockLength, blockLength, blockLength,
+        blockLength, blockLength};
+    long safeLength = new BlockLengths(ecPolicy, blockLengths).getSafeLength();
+    Assert.assertEquals(expectedSafeLength, safeLength);
+  }
+
   private void runTest(int[] blockLengths, long safeLength) throws Exception {
     writePartialBlocks(blockLengths);