static int may_o_create(const struct path *dir, struct dentry *dentry, umode_t mode)
{
	struct user_namespace *s_user_ns;
	int error = security_path_mknod(dir, dentry, mode, 0);
	if (error)
		return error;

	s_user_ns = dir->dentry->d_sb->s_user_ns;
	if (!kuid_has_mapping(s_user_ns, current_fsuid()) ||
	    !kgid_has_mapping(s_user_ns, current_fsgid()))
		return -EOVERFLOW;

	error = inode_permission(dir->dentry->d_inode, MAY_WRITE | MAY_EXEC);
	if (error)
		return error;

	return security_inode_create(dir->dentry->d_inode, dentry, mode);
}

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.