Re: [PATCH v7 0/3] fanotify: Allow user space to pass back additional audit info

On Fri 03-02-23 16:35:13, Richard Guy Briggs wrote: > The Fanotify API can be used for access control by requesting permission > event notification. The user space tooling that uses it may have a > complicated policy that inherently contains additional context for the > decision. If this information were available in the audit trail, policy > writers can close the loop on debugging policy. Also, if this additional > information were available, it would enable the creation of tools that > can suggest changes to the policy similar to how audit2allow can help > refine labeled security. > > This patchset defines a new flag (FAN_INFO) and new extensions that > define additional information which are appended after the response > structure returned from user space on a permission event. The appended > information is organized with headers containing a type and size that > can be delegated to interested subsystems. One new information type is > defined to audit the triggering rule number. > > A newer kernel will work with an older userspace and an older kernel > will behave as expected and reject a newer userspace, leaving it up to > the newer userspace to test appropriately and adapt as necessary. This > is done by providing a a fully-formed FAN_INFO extension but setting the > fd to FAN_NOFD. On a capable kernel, it will succeed but issue no audit > record, whereas on an older kernel it will fail. > > The audit function was updated to log the additional information in the > AUDIT_FANOTIFY record. The following are examples of the new record > format: > type=FANOTIFY msg=audit(1600385147.372:590): resp=2 fan_type=1 fan_info=3137 subj_trust=3 obj_trust=5 > type=FANOTIFY msg=audit(1659730979.839:284): resp=1 fan_type=0 fan_info=0 subj_trust=2 obj_trust=2 Thanks! I've applied this series to my tree.