Re: [PATCH ALT4 V2 2/2] audit: filter PATH records keyed on filesystem magic

[Richard Guy Briggs]

On 2017-06-28 15:08, Paul Moore wrote:
> On Tue, Jun 27, 2017 at 4:45 PM, Richard Guy Briggs <rgb@xxxxxxxxxx> wrote:
> > On 2017-05-30 17:30, Paul Moore wrote:
> >> On Tue, Apr 4, 2017 at 5:21 AM, Richard Guy Briggs <rgb@xxxxxxxxxx> wrote:
> >> > Tracefs or debugfs were causing hundreds to thousands of PATH records to
> >> > be associated with the init_module and finit_module SYSCALL records on a
> >> > few modules when the following rule was in place for startup:
> >> >         -a always,exit -F arch=x86_64 -S init_module -F key=mod-load
> >> >
> >> > Provide a method to ignore these large number of PATH records from
> >> > overwhelming the logs if they are not of interest.  Introduce a new
> >> > filter list "AUDIT_FILTER_PATH", with a new field type AUDIT_FSTYPE,
> >> > which keys off the filesystem 4-octet hexadecimal magic identifier to
> >> > filter specific filesystem PATH records.
> >> >
> >> > An example rule would look like:
> >> >         -a never,path -F fstype=0x74726163 -F key=ignore_tracefs
> >> >         -a never,path -F fstype=0x64626720 -F key=ignore_debugfs
> >>
> >> Trying to look into the future I wonder if we are ever going to need
> >> to expand the "path" filtering to regular inode lookups, e.g.
> >> audit_inode()?
> >
> > That thought had occurred to me.  Do you see any concern with that that
> > would affect this patch in terms of naming?
> 
> Well, you want to change this to "fs" now instead of "path", right?  I
> think that removes my concerns.

That's fixed in my cleanup that I'm waiting to push.  In fact it is
"filesystem" in the userspace patch.

> > I could see expanding this filter to include other filter fields though
> > nothing specific comes to mind now.
> 
> paul moore

- RGB

--
Richard Guy Briggs <rgb@xxxxxxxxxx>
Sr. S/W Engineer, Kernel Security, Base Operating Systems
Remote, Ottawa, Red Hat Canada
IRC: rgb, SunRaycer
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