static int isofs_bmap(struct inode *inode, sector_t block)
{
	struct buffer_head dummy;
	int error;

	dummy.b_state = 0;
	dummy.b_blocknr = -1000;
	error = isofs_get_block(inode, block, &dummy, 0);
	if (!error)
		return dummy.b_blocknr;
	return 0;
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.