public inbox for linux-xfs@vger.kernel.org
 help / color / mirror / Atom feed
From: Dave Chinner <david@fromorbit.com>
To: Dwight Engen <dwight.engen@oracle.com>
Cc: xfs@oss.sgi.com
Subject: Re: [PATCH v7 6/7] xfs: add capable check to free eofblocks ioctl
Date: Wed, 31 Jul 2013 09:16:06 +1000	[thread overview]
Message-ID: <20130730231606.GO13468@dastard> (raw)
In-Reply-To: <20130729230705.128e4509@oracle.com>

On Mon, Jul 29, 2013 at 11:07:05PM -0400, Dwight Engen wrote:
> Check for CAP_SYS_ADMIN since the caller can truncate preallocated
> blocks from files they do not own nor have write access to. A more
> fine grained access check was considered: require the caller to
> specify their own uid/gid and to use inode_permission to check for
> write, but this would not catch the case of an inode not reachable
> via path traversal from the callers mount namespace.
> 
> Add check for read-only filesystem to free eofblocks ioctl.
> 
> Signed-off-by: Dwight Engen <dwight.engen@oracle.com>
> ---
>  fs/xfs/xfs_ioctl.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
> index 6e72eff..b1990ac 100644
> --- a/fs/xfs/xfs_ioctl.c
> +++ b/fs/xfs/xfs_ioctl.c
> @@ -1613,6 +1613,12 @@ xfs_file_ioctl(
>  		struct xfs_fs_eofblocks eofb;
>  		struct xfs_eofblocks keofb;
>  
> +		if (!capable(CAP_SYS_ADMIN))
> +			return -EPERM;
> +
> +		if (IS_RDONLY(inode))
> +			return -XFS_ERROR(EROFS);
> +
>  		if (copy_from_user(&eofb, arg, sizeof(eofb)))
>  			return -XFS_ERROR(EFAULT);

Looks fine.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
-- 
Dave Chinner
david@fromorbit.com

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

  parent reply	other threads:[~2013-07-30 23:16 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-07-30  3:07 [PATCH v7 6/7] xfs: add capable check to free eofblocks ioctl Dwight Engen
2013-07-30 12:33 ` Brian Foster
2013-07-30 23:27   ` Dave Chinner
2013-07-30 23:16 ` Dave Chinner [this message]
2013-07-31  7:14 ` Gao feng

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=20130730231606.GO13468@dastard \
    --to=david@fromorbit.com \
    --cc=dwight.engen@oracle.com \
    --cc=xfs@oss.sgi.com \
    /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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox