src/java.base/share/classes/jdk/internal/jimage/ImageStringsReader.java

rev 14631 : 8156209: Add argument checks to BasicImageReader calls
Reviewed-by: sundar

*** 25,34 ****
--- 25,35 ----
  
  package jdk.internal.jimage;
  
  import java.io.UTFDataFormatException;
  import java.nio.ByteBuffer;
+ import java.util.Objects;
  
  /**
   * @implNote This class needs to maintain JDK 8 source compatibility.
   *
   * It is used internally in the JDK to implement jimage/jrtfs access,
*** 38,47 ****
--- 39,49 ----
  public class ImageStringsReader implements ImageStrings {
      public static final int HASH_MULTIPLIER = 0x01000193;
      private final BasicImageReader reader;
  
      ImageStringsReader(BasicImageReader reader) {
+         Objects.requireNonNull(reader);
          this.reader = reader;
      }
  
      @Override
      public String get(int offset) {
*** 52,62 ****
      public int add(final String string) {
          throw new InternalError("Can not add strings at runtime");
      }
  
      private static int hashCode(byte[] bytes, int offset, int count, int seed) {
!         for (int i = offset, limit = offset + count; i < limit; i++) {
              seed = (seed * HASH_MULTIPLIER) ^ (bytes[i] & 0xFF);
          }
  
          return seed & 0x7FFFFFFF;
      }
--- 54,76 ----
      public int add(final String string) {
          throw new InternalError("Can not add strings at runtime");
      }
  
      private static int hashCode(byte[] bytes, int offset, int count, int seed) {
!         Objects.requireNonNull(bytes);
!         
!         if (offset < 0 || offset >= bytes.length) {
!             throw new IndexOutOfBoundsException("offset");
!         }
!         
!         int limit = offset + count;
!         
!         if (limit < 0 || limit > bytes.length) {
!             throw new IndexOutOfBoundsException("limit");
!         }
! 
!         for (int i = offset; i < limit; i++) {
              seed = (seed * HASH_MULTIPLIER) ^ (bytes[i] & 0xFF);
          }
  
          return seed & 0x7FFFFFFF;
      }