Problem:
*** We need to test for len < 0 then throw ArrayIndexOutOfBoundsException ***
*** We need to test for off+len > datalen then throw ArrayIndexOutOfBoundsException ***

The Java Specification Language: Reference 22.3.3
public int read(byte[] b, int off, int len)
throws IOException, NullPointerException,
IndexOutOfBoundsException

If off is negative, or len is negative, or off+len is greater than the length of the array b, then an
IndexOutOfBoundsException is thrown.


JAVA CODE for read calls native readBytes
JAVA WORKSPACE TREE: /src/share/java/lang
File: io.c

Sections of code in question:
*** java_io_FileInputStream_readBytes(Hjava_io_FileInputStream *this, HArrayOfByte *data, long off, long len)

*** java_io_RandomAccessFile_readBytes(Hjava_io_RandomAccessFile *this, HArrayOfByte *data, long off, long len)

Code snippet:
    dataptr = unhand(data)->body;
    datalen = obj_length(data);


*** We need to test for below description in FileInputStream + RandomAccessFile native code for readBytes ***

DESCRIPTION OF PROBLEM:

*** We need to test for len < 0 then throw ArrayIndexOutOfBoundsException ***
*** We need to test for off+len > datalen then throw ArrayIndexOutOfBoundsException ***


*** Could use code: if ((off < 0) || (len < 0)|| ( off + len > datalen)||(off > datalen)) { ***

*** Use above line instead of below line ***
    if ((off < 0) || (off > datalen)) { *** Does not check all cases for throwing exceptions
SignalError(0, JAVAPKG "ArrayIndexOutOfBoundsException", 0);
return -1;
    }

********************************************************
*** This should be covered above and throw exception ***

    if (off + len > datalen) {
len = datalen - off;
    }
********************************************************

********************************************************
*** Change the len <= 0 to len = 0 the return zero ***
    if (len <= 0) {
return 0;
    }
********************************************************
    n = sysReadFD(fdptr, dataptr + off, len);
    if (n == -1) {
SignalError(0, IO_EXCEPTION, "read error");
    }

    /* AVH: this is bogus but it stops the pointer from being gc'd */
    KEEP_POINTER_ALIVE(dataptr);
    return (n == 0) ? -1 : n;

*******************************************************************************************

How to reproduce bug:
Use below test to test against errors:
change (off) and (len) values described below.

off=0 len=5 buf.size=5 This will test if we can read array size that matches off+len
off=1 len=5 buf.size=5 This will test if off+len is greater than buf.size then throw exception
off=-1 len=5 buf.size=5 This will test if off is negative then throw exception
off=1 len=-5 buf.size=5 This will test if len is negative then throw exception
off=6 len=1 buf.size=5 This will test if off is greater than buf.size then throw exception

Test Code:

import java.io.*;

public class readbytes_test {

    public static void main(String argv[]) {
      try {
byte buf[] = new byte[5];
int off = 0;
int len = 5;
// Tests that need to be run
// off=0 len=5 buf.size=5 This will test if we can read array size that matches off+len
// off=1 len=5 buf.size=5 This will test if off+len is greater than buf.size then throw exception
// off=-1 len=5 buf.size=5 This will test if off is negative then throw exception
// off=1 len=-5 buf.size=5 This will test if len is negative then throw exception
// off=6 len=1 buf.size=5 This will test if off is greater than buf.size then throw exception


// Test for FileInputStream (read) Method which calls native readBytes

FileInputStream f = new FileInputStream("./test.txt");
System.out.println("Array.length = "+buf.length);
System.out.println("Bytes Read: " + f.read(buf, off, len));

// Loops through array and prints out buffer values

for (int i = 0; i < buf.length; i++){
System.out.println("buffer["+i+"] value = " + buf[i]);
}

// Test for RandomAccessFile (read) Method which calls native readBytes

RandomAccessFile raf = new RandomAccessFile("./test.txt", "r");
System.out.println("Array.length = "+buf.length);
System.out.println("Bytes Read: " + f.read(buf, off, len));

// Loops through array and prints out buffer values

for (int i = 0; i < buf.length; i++){
System.out.println("buf["+i+"] = " + buf[i]);
}
      }
      catch (Exception x) {
x.printStackTrace();
      }
    }
}