static void init_skiplist(struct fsck_options *options, const char *path)
{
	static struct oid_array skiplist = OID_ARRAY_INIT;
	int sorted, fd;
	char buffer[GIT_MAX_HEXSZ + 1];
	struct object_id oid;

	if (options->skiplist)
		sorted = options->skiplist->sorted;
	else {
		sorted = 1;
		options->skiplist = &skiplist;
	}

	fd = open(path, O_RDONLY);
	if (fd < 0)
		die("Could not open skip list: %s", path);
	for (;;) {
		const char *p;
		int result = read_in_full(fd, buffer, sizeof(buffer));
		if (result < 0)
			die_errno("Could not read '%s'", path);
		if (!result)
			break;
		if (parse_oid_hex(buffer, &oid, &p) || *p != '\n')
			die("Invalid SHA-1: %s", buffer);
		oid_array_append(&skiplist, &oid);
		if (sorted && skiplist.nr > 1 &&
				oidcmp(&skiplist.oid[skiplist.nr - 2],
				       &oid) > 0)
			sorted = 0;
	}
	close(fd);

	if (sorted)
		skiplist.sorted = 1;
}

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.