Re: [PATCH v22 01/12] landlock: Add object management

Hi!

A Landlock object enables to identify a kernel object (e.g. an inode). A Landlock rule is a set of access rights allowed on an object. Rules are grouped in rulesets that may be tied to a set of processes (i.e. subjects) to enforce a scoped access-control (i.e. a domain).

Because Landlock's goal is to empower any process (especially unprivileged ones) to sandbox themselves, we cannot rely on a system-wide object identification such as file extended attributes.

+config SECURITY_LANDLOCK

• bool "Landlock support"
• depends on SECURITY
• select SECURITY_PATH
• help

•  Landlock is a safe sandboxing mechanism which enables processes to
  

•  restrict themselves (and their future children) by gradually
  

•  enforcing tailored access control policies.  A security policy is a
  

•  set of access rights (e.g. open a file in read-only, make a
  

•  directory, etc.) tied to a file hierarchy.  Such policy can be configured
  

•  and enforced by any processes for themselves thanks to dedicated system
  

•  calls: landlock_create_ruleset(), landlock_add_rule(), and
  

•  landlock_enforce_ruleset_current().
  

How does it interact with setuid binaries? Being able to exec passwd in a sandbox sounds like ... fun way to get root? :-).

Best regards, Pavel