Heap-buffer-overflow write in FFmpeg EXR dwa_uncompress

When decoding an OpenEXR file that uses DWAA or DWAB compression, the specified raw length of run-length-encoded data is not checked when using it to calculate the output data. We read rle_raw_size from the input file at [0], we decompress and decode into the buffer td->rle_raw_data of size rle_raw_size at [1], and then at [2] we will access entries in this buffer up to (td->xsize - 1) * (td->ysize - 1) + rle_raw_size / 2, which may exceed rle_raw_size. We recommend upgrading to version 8.0 or beyond.