On 08/02/16 21:54, Aleksey Shipilev wrote:
...
Still, the corrupted stream may call readUTFBody(1L +
Integer.MAX_VALUE), that yields initial capacity of -2147483648, which
in turn fails StringBuilder(...) with NegativeArraySizeException. But I
wonder if that is actually a valid UTF8 input, because you cannot have
that large of a String...
Right. To retain existing behavior (negative sizes => empty string)
then we can just short-circuit this.
diff --git a/src/java.base/share/classes/java/io/ObjectInputStream.java
b/src/java.base/share/classes/java/io/ObjectInputStream.java
--- a/src/java.base/share/classes/java/io/ObjectInputStream.java
+++ b/src/java.base/share/classes/java/io/ObjectInputStream.java
@@ -3144,7 +3144,12 @@
* utflen bytes.
*/
private String readUTFBody(long utflen) throws IOException {
- StringBuilder sbuf = new StringBuilder();
+ if (utflen < 0)
+ return "";
+
+ // a reasonable initial capacity based on the UTF length
+ int initialCapacity = Math.min((int)utflen, 16384);
+ StringBuilder sbuf = new StringBuilder(initialCapacity);
if (!blkmode) {
end = pos = 0;
}
-Chris.
