muxread: fix 0 offset of NULL pointer
@@ -100,7 +100,7 @@ static int MuxImageParse(const WebPChunk* const chunk, int copy_data,
WebPMuxImage* const wpi) {
const uint8_t* bytes = chunk->data_.bytes;
size_t size = chunk->data_.size;
- const uint8_t* const last = bytes + size;
+ const uint8_t* const last = (bytes == NULL) ? NULL : bytes + size;
WebPChunk subchunk;
size_t subchunk_size;
WebPChunk** unknown_chunk_list = &wpi->unknown_;
