xfs
[Top] [All Lists]

Re: [PATCH v3 2/4] xfs: initialize inode security on tmpfile creation

To: Stephen Smalley <sds@xxxxxxxxxxxxx>
Subject: Re: [PATCH v3 2/4] xfs: initialize inode security on tmpfile creation
From: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Date: Wed, 16 Apr 2014 07:14:09 -0700
Cc: Brian Foster <bfoster@xxxxxxxxxx>, linux-fsdevel@xxxxxxxxxxxxxxx, linux-security-module@xxxxxxxxxxxxxxx, xfs@xxxxxxxxxxx, Eric Paris <eparis@xxxxxxxxxxxxxx>, Paul Moore <paul@xxxxxxxxxxxxxx>
Delivered-to: xfs@xxxxxxxxxxx
In-reply-to: <534E7CDA.2060805@xxxxxxxxxxxxx>
References: <1397578706-5385-1-git-send-email-bfoster@xxxxxxxxxx> <1397578706-5385-3-git-send-email-bfoster@xxxxxxxxxx> <20140415175033.GB26404@xxxxxxxxxxxxx> <534D90D0.9090805@xxxxxxxxxxxxx> <20140415202222.GA10928@xxxxxxxxxxxxx> <534D94E4.8070606@xxxxxxxxxxxxx> <534E7CDA.2060805@xxxxxxxxxxxxx>
User-agent: Mutt/1.5.21 (2010-09-15)
On Wed, Apr 16, 2014 at 08:51:38AM -0400, Stephen Smalley wrote:
> Maybe I spoke too soon.  IIUC, I_LINKABLE doesn't necessarily
> distinguish tmpfiles from other files, as some tmpfiles may be linkable
> and others not.  But what we want is a way to identify all tmpfiles when
> security_inode_init_security() is called if we are going to label them
> independently of the provided dir.

Oh, right.  If O_EXCL is specified (another annoying overload of the
flag..) the tmpfile can't ever be linked back into the filesystem
and thus doesn't have I_LINKABLE set.

I guess the best way to fix this is using the magic qstr you suggested
before.  That means security_inode_init_security would need to be
called after d_tmpfile, which most filesystems don't do right now.

<Prev in Thread] Current Thread [Next in Thread>