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Date: Tue, 12 Feb 2008 15:51:37 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: David Howells <dhowells@redhat.com>
Cc: torvalds@linux-foundation.org, linux-kernel@vger.kernel.org,
       dhowells@redhat.com
Subject: Re: [PATCH 4/4] KEYS: Add keyctl function to get a security label
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On Fri, 08 Feb 2008 16:04:40 +0000
David Howells <dhowells@redhat.com> wrote:

> +	key_ref = lookup_user_key(NULL, keyid, 0, 1, KEY_VIEW);
> +	if (IS_ERR(key_ref)) {
> +		if (PTR_ERR(key_ref) != -EACCES)
> +			return PTR_ERR(key_ref);
> +
> +		/* viewing a key under construction is also permitted if we
> +		 * have the authorisation token handy */
> +		instkey = key_get_instantiation_authkey(keyid);
> +		if (IS_ERR(instkey))
> +			return PTR_ERR(key_ref);
> +		key_put(instkey);

This check looks a wee bit racy?