linux-kernel - Re: [RFC PATCH 5/5] gfs2: Add xreaddir file operation and supporting functions

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20140729145808.79bec165@lwn.net>
Date:	Tue, 29 Jul 2014 14:58:08 -0400
From:	Jonathan Corbet <corbet@....net>
To:	Abhi Das <adas@...hat.com>
Cc:	linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
	cluster-devel@...hat.com
Subject: Re: [RFC PATCH 5/5] gfs2: Add xreaddir file operation and
 supporting functions

On Fri, 25 Jul 2014 12:38:08 -0500
Abhi Das <adas@...hat.com> wrote:

> This patch adds support in GFS2 for the xgetdents syscall by
> implementing the xreaddir file operation.

So I was trying to make sense of this, and ran into one little thing that
jumped out at me:

> +static int gfs2_xrdir_to_user_vars(struct gfs2_xrdir_ctx *xc,
> +				   struct gfs2_xdirent *x,
> +				   struct gfs2_xdirent *x_vb_p,
> +				   struct linux_xdirent __user *lxd,
> +				   size_t count, size_t *bytes)

Now, I'll readily admit that I could be overly confused by this function.
When the variables are named "x", "xx", "xc", "x_vb_p", "xblob", and "lxd",
it all starts to run together.  But still...

> +	if ((xc->xc_xattr_mask & XSTAT_XATTR_ALL) &&
> +		lxd->xd_blob.xb_xattr_count) {

How can that be right?  lxd is __user, it doesn't seem right to be
dereferencing it directly...?

Thanks,

jon
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/