static long do_unlinkat(int dfd, const char __user *pathname)
{
	int error;
	char *name;
	struct dentry *dentry;
	struct nameidata nd;
	struct inode *inode = NULL;

	error = user_path_parent(dfd, pathname, &nd, &name);
	if (error)
		return error;

	error = -EISDIR;
	if (nd.last_type != LAST_NORM)
		goto exit1;

	nd.flags &= ~LOOKUP_PARENT;

	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
	dentry = lookup_hash(&nd);
	error = PTR_ERR(dentry);
	if (!IS_ERR(dentry)) {
		/* Why not before? Because we want correct error value */
		if (nd.last.name[nd.last.len])
			goto slashes;
		inode = dentry->d_inode;
		if (inode)
			atomic_inc(&inode->i_count);
		error = mnt_want_write(nd.path.mnt);
		if (error)
			goto exit2;
		error = security_path_unlink(&nd.path, dentry);
		if (error)
			goto exit3;
		error = vfs_unlink(nd.path.dentry->d_inode, dentry);
exit3:
		mnt_drop_write(nd.path.mnt);
	exit2:
		dput(dentry);
	}
	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
	if (inode)
		iput(inode);	/* truncate the inode here */
exit1:
	path_put(&nd.path);
	putname(name);
	return error;

slashes:
	error = !dentry->d_inode ? -ENOENT :
		S_ISDIR(dentry->d_inode->i_mode) ? -EISDIR : -ENOTDIR;
	goto exit2;
}

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.