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

From: Paul Moore
Date: Wed Jun 28 2017 - 15:08:29 EST


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.

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

--
paul moore
www.paul-moore.com