LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Dave Quigley <dpquigl@tycho.nsa.gov>
To: James Morris <jmorris@namei.org>
Cc: hch@infradead.org, viro@ftp.linux.org.uk,
	trond.myklebust@fys.uio.no, bfields@fieldses.org,
	linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 08/11] NFS: Introduce lifecycle management for label attribute.
Date: Wed, 27 Feb 2008 19:47:53 -0500	[thread overview]
Message-ID: <1204159673.24345.15.camel@moss-terrapins.epoch.ncsc.mil> (raw)
In-Reply-To: <Xine.LNX.4.64.0802281157170.27221@us.intercode.com.au>


On Thu, 2008-02-28 at 12:04 +1100, James Morris wrote:
> On Wed, 27 Feb 2008, David P. Quigley wrote:
> 
> > +#ifdef CONFIG_SECURITY
> > +static inline void nfs_fattr_alloc(struct nfs_fattr *fattr, gfp_t flags)
> > +{
> > +	fattr->label = kzalloc(NFS4_MAXLABELLEN, flags);
> > +	if (fattr->label == NULL)
> > +		panic("Can't allocate security label.");
> > +	fattr->label_len = NFS4_MAXLABELLEN;
> > +}
> 
> A panic here seems like overkill, and also possibly a DoS vector.  I 
> suggest having the calling code handle the allocation failure gracefully.
> 

Good point, I'll put this on the list. I think I remember you mentioned
something about this before but it must have slipped through the cracks.

> > +
> > +#define	nfs_fattr_fini(fattr)	_nfs_fattr_fini(fattr, __FILE__, __LINE__, __func__)
> > +static inline void _nfs_fattr_fini(struct nfs_fattr *fattr,
> > +		const char *file, int line, const char *func)
> > +{
> > +	if ((fattr)->label == NULL) {
> > +		if (fattr->label_len != 0) {
> > +			printk(KERN_WARNING
> > +					"%s:%d %s() nfs_fattr label available (%d)\n",
> > +					file, line, func,
> > +					fattr->label_len);
> > +		}
> > +	} else {
> > +		if (fattr->label_len == NFS4_MAXLABELLEN)
> > +			printk(KERN_WARNING
> > +					"%s:%d %s() nfs_fattr label unused\n",
> > +					file, line, func);
> > +		else if (fattr->label_len != (strlen(fattr->label) + 1))
> > +			printk(KERN_WARNING
> > +				"%s:%d %s() nfs_fattr label size mismatch (label_len %d, strlen %d)\n",
> > +				file, line, func,
> > +				fattr->label_len, strlen(fattr->label) + 1);
> > +
> > +		kfree(fattr->label);
> > +		fattr->label = NULL;
> > +		fattr->label_len = 0;
> > +	}
> > +}
> > +#else
> > +#define	nfs_fattr_alloc(fattr, flags)
> > +#define	nfs_fattr_fini(fattr)
> > +#endif
> 
> Perhaps introduce a debug configuration option for this code.

In what way? We can change them to respond to the NFS/NFSD debug
variables that are set through proc, or did you have something else in
mind?

> 
> 
> - James


  reply	other threads:[~2008-02-28  1:12 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-02-27 20:39 RFC Labeled NFS Initial Code Review David P. Quigley
2008-02-27 20:39 ` [PATCH 01/11] Security: Add hook to get full maclabel xattr name David P. Quigley
2008-02-27 20:39 ` [PATCH 02/11] Security: Add hook to calculate context based on a negative dentry David P. Quigley
2008-02-27 20:39 ` [PATCH 03/11] VFS: Add security label support to *notify David P. Quigley
2008-02-28 20:10   ` Josef 'Jeff' Sipek
2008-02-28 20:39     ` Dave Quigley
2008-02-28 21:15       ` Josef 'Jeff' Sipek
2008-02-28 21:05         ` Dave Quigley
2008-02-28 21:39           ` Josef 'Jeff' Sipek
2008-02-28 21:26             ` Dave Quigley
2008-02-29  6:57   ` Andrew Morton
2008-02-27 20:39 ` [PATCH 04/11] KConfig: Add KConfig entries for SELinux labeled NFS David P. Quigley
2008-02-27 20:39 ` [PATCH 05/11] NFSv4: Add label recommended attribute and NFSv4 flags David P. Quigley
2008-02-27 20:39 ` [PATCH 06/11] SELinux: Add new labeling type native labels David P. Quigley
2008-02-27 20:39 ` [PATCH 07/11] NFS/SELinux: Add security_label text mount option to nfs and add handling code to the security server David P. Quigley
2008-02-27 20:39 ` [PATCH 08/11] NFS: Introduce lifecycle management for label attribute David P. Quigley
2008-02-28  1:04   ` James Morris
2008-02-28  0:47     ` Dave Quigley [this message]
2008-02-28  1:22       ` James Morris
2008-02-28 20:07     ` Dave Quigley
2008-02-28 23:00       ` James Morris
2008-02-28 22:43         ` Dave Quigley
2008-02-27 20:39 ` [PATCH 09/11] NFS: Client implementation of Labeled-NFS David P. Quigley
2008-02-27 20:39 ` [PATCH 10/11] NFS: Extend nfs xattr handlers to accept the security namespace David P. Quigley
2008-02-27 20:39 ` [PATCH 11/11] NFSD: Server implementation of MAC Labeling David P. Quigley
2008-02-27 22:11 RFC Labeled NFS Initial Code Review David P. Quigley
2008-02-27 22:11 ` [PATCH 08/11] NFS: Introduce lifecycle management for label attribute David P. Quigley
2008-02-28  4:13   ` James Morris
2008-02-28 16:24     ` Dave Quigley
2008-02-28 16:46   ` Dave Quigley

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1204159673.24345.15.camel@moss-terrapins.epoch.ncsc.mil \
    --to=dpquigl@tycho.nsa.gov \
    --cc=bfields@fieldses.org \
    --cc=hch@infradead.org \
    --cc=jmorris@namei.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=trond.myklebust@fys.uio.no \
    --cc=viro@ftp.linux.org.uk \
    --subject='Re: [PATCH 08/11] NFS: Introduce lifecycle management for label attribute.' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).