Fixes the following security issues:
- CVE-2021-41089: Create parent directories inside a chroot during docker
cp to prevent a specially crafted container from changing permissions of
existing files in the host’s filesystem.
- CVE-2021-41091: Lock down file permissions to prevent unprivileged users
from discovering and executing programs in /var/lib/docker.
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Reviewed-by: Christian Stewart <christian@paral.in>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>