Fix handling of corrupt RLE data (#2156)

* Fix handling of corrupt RLE data

If the size of the uncompressed RLE data does not match the expected
output size, the chunk is corrupt, so report an error.

Signed-off-by: Cary Phillips <cary@ilm.com>

* remove packsz>0 because of the packsize==0 above

Signed-off-by: Cary Phillips <cary@ilm.com>

---------

Signed-off-by: Cary Phillips <cary@ilm.com>

Author: cary-ilm

src/lib/OpenEXRCore/internal_rle.c

@@ -219,7 +219,7 @@ internal_exr_undo_rle (
 
     unpackb =
         internal_rle_decompress (decode->scratch_buffer_1, outsz, src, packsz);
-    if (packsz > 0 && unpackb == 0)
+    if (unpackb != outsz)
         return EXR_ERR_CORRUPT_CHUNK;
 
     unpredict_and_reorder (out, decode->scratch_buffer_1, unpackb);