From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Howells <dhowells@redhat.com>
Subject: Re: [PATCH 7/8] SELinux: Create a common helper to determine an inode label
Date: Thu, 18 Jun 2015 16:13:51 +0100
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References: <5582DC0F.7090800@tycho.nsa.gov> <20150618133215.12722.70352.stgit@warthog.procyon.org.uk> <20150618133310.12722.16624.stgit@warthog.procyon.org.uk>
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To: Stephen Smalley <sds@tycho.nsa.gov>
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Stephen Smalley <sds@tycho.nsa.gov> wrote:

> > +	if ((sbsec->flags & SE_SBINITIALIZED) &&
> > +		   (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
> > +		*_new_isid = sbsec->mntpoint_sid;
> > +	} else if (tsec->create_sid) {
> 
> This doesn't quite match the logic in inode_init_security today, see its
> checking of SBLABEL_MNT.

Fair point.  What does SBLABEL_MNT mean precisely?  It seems to indicate one
of an odd mix of behaviours.  I presume it means that we *have* to calculate a
label and can't get one from the underlying fs if it is not set.

Also, in:

	sbsec->flags |= SE_SBINITIALIZED;
	if (selinux_is_sblabel_mnt(sb))
		sbsec->flags |= SBLABEL_MNT;

should SE_SBINITIALIZED be set after SBLABEL_MNT?  And should there be a
memory barrier in here somewhere before the setting of SE_SBINITIALIZED?

David

From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Howells <dhowells@redhat.com>
In-Reply-To: <5582DC0F.7090800@tycho.nsa.gov>
References: <5582DC0F.7090800@tycho.nsa.gov>
 <20150618133215.12722.70352.stgit@warthog.procyon.org.uk>
 <20150618133310.12722.16624.stgit@warthog.procyon.org.uk>
To: Stephen Smalley <sds@tycho.nsa.gov>
Subject: Re: [PATCH 7/8] SELinux: Create a common helper to determine an inode
 label
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Date: Thu, 18 Jun 2015 16:13:51 +0100
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Cc: miklos@szeredi.hu, linux-unionfs@vger.kernel.org,
 linux-kernel@vger.kernel.org, dhowells@redhat.com,
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Stephen Smalley <sds@tycho.nsa.gov> wrote:

> > +	if ((sbsec->flags & SE_SBINITIALIZED) &&
> > +		   (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
> > +		*_new_isid = sbsec->mntpoint_sid;
> > +	} else if (tsec->create_sid) {
> 
> This doesn't quite match the logic in inode_init_security today, see its
> checking of SBLABEL_MNT.

Fair point.  What does SBLABEL_MNT mean precisely?  It seems to indicate one
of an odd mix of behaviours.  I presume it means that we *have* to calculate a
label and can't get one from the underlying fs if it is not set.

Also, in:

	sbsec->flags |= SE_SBINITIALIZED;
	if (selinux_is_sblabel_mnt(sb))
		sbsec->flags |= SBLABEL_MNT;

should SE_SBINITIALIZED be set after SBLABEL_MNT?  And should there be a
memory barrier in here somewhere before the setting of SE_SBINITIALIZED?

David