Handle empty files correctly when looking for FileMagic to avoid NegativeArraySizeException

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1873232 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Dominik Stadler 2020-01-27 22:54:15 +00:00
parent 31eb7f9b06
commit 366c80c480
2 changed files with 13 additions and 3 deletions

View File

@ -113,7 +113,7 @@ public enum FileMagic {
final static int MAX_PATTERN_LENGTH = 44;
final byte[][] magic;
FileMagic(long magic) {
this.magic = new byte[1][8];
LittleEndian.putLong(this.magic[0], 0, magic);
@ -122,7 +122,7 @@ public enum FileMagic {
FileMagic(byte[]... magic) {
this.magic = magic;
}
FileMagic(String... magic) {
this.magic = new byte[magic.length][];
int i=0;
@ -172,6 +172,9 @@ public enum FileMagic {
// read as many bytes as possible, up to the required number of bytes
byte[] data = new byte[MAX_PATTERN_LENGTH];
int read = IOUtils.readFully(fis, data, 0, MAX_PATTERN_LENGTH);
if(read == -1) {
return FileMagic.UNKNOWN;
}
// only use the bytes that could be read
data = Arrays.copyOf(data, read);

View File

@ -107,8 +107,15 @@ public class TestFileMagic {
@Test
public void testShortFile() throws IOException {
// having a file shorter than 8 bytes previously caused an exception
byte[] data = new byte[] { -1, -40, -1, -32, 0 };
fetchMagicFromData(new byte[] { -1, -40, -1, -32, 0 });
fetchMagicFromData(new byte[] { -1, -40, -1, -32 });
fetchMagicFromData(new byte[] { -1, -40, -1 });
fetchMagicFromData(new byte[] { -1, -40 });
fetchMagicFromData(new byte[] { -1 });
fetchMagicFromData(new byte[0]);
}
private void fetchMagicFromData(byte[] data) throws IOException {
File file = TempFile.createTempFile("TestFileMagic", ".bin");
try {
try (FileOutputStream fos = new FileOutputStream(file)) {