Re: [PATCH v5 3/3] fanotify,audit: Allow audit to use the full permission event response

From: Steve Grubb <sgrubb@redhat.com>
To: Richard Guy Briggs <rgb@redhat.com>
Cc: Linux-Audit Mailing List <linux-audit@redhat.com>,
	LKML <linux-kernel@vger.kernel.org>,
	linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org,
	Paul Moore <paul@paul-moore.com>,
	Eric Paris <eparis@parisplace.org>, Jan Kara <jack@suse.cz>,
	Amir Goldstein <amir73il@gmail.com>
Subject: Re: [PATCH v5 3/3] fanotify,audit: Allow audit to use the full permission event response
Date: Tue, 10 Jan 2023 10:26:00 -0500	[thread overview]
Message-ID: <4778109.GXAFRqVoOG@x2> (raw)
In-Reply-To: <Y7zWlFbrrNcfGauJ@madcap2.tricolour.ca>

Hello Richard,

On Monday, January 9, 2023 10:08:04 PM EST Richard Guy Briggs wrote:
> When I use an application that expected the old API, meaning it simply
> does:
> > 
> > response.fd = metadata->fd;
> > response.response = reply;
> > close(metadata->fd);
> > write(fd, &response, sizeof(struct fanotify_response));
> > 
> > I get access denials. Every time. If the program is using the new API and
> > sets FAN_INFO, then it works as expected. I'll do some more testing but I
> > think there is something wrong in the compatibility path.
> 
> I'll have a closer look, because this wasn't the intended behaviour.

I have done more testing. I think what I saw might have been caused by a 
stale selinux label (label exists, policy is deleted). With selinux in 
permissive mode it's all working as expected - both old and new API.

-Steve