From: Andrew Morton <akpm@linux-foundation.org>
To: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: casey@schaufler-ca.com, paul.moore@hp.com,
linux-security-module@vger.kernel.org,
linux-kernel@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: [PATCH BUGFIX -v2 -rc4] Smack: Respect 'unlabeled' netlabel mode
Date: Fri, 30 May 2008 16:25:00 -0700 [thread overview]
Message-ID: <20080530162500.1411f14d.akpm@linux-foundation.org> (raw)
In-Reply-To: <20080530235751.GA6888@ubuntu>
On Sat, 31 May 2008 02:57:51 +0300
"Ahmed S. Darwish" <darwish.07@gmail.com> wrote:
> + mutex_lock(&smack_ambient_lock);
> + nlsp->domain = kstrdup(smack_net_ambient, GFP_ATOMIC);
> + mutex_unlock(&smack_ambient_lock);
no no no no no. And no.
GFP_ATOMIC is *unreliable*. Using it in a "security" feature is a bug
- if it fails, the feature isn't secure any more.
Failing to check the kmalloc() return value might be a bug.
If we _need_ GFP_ATOMIC here then taking a mutex in a cannot-sleep
context is a bug.
The patch adds a kmalloc but doesn't add a kfree. Is it leaky?
Finally, why is there a need to take a lock around a single store
instruction?
next prev parent reply other threads:[~2008-05-30 23:25 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-05-30 23:36 [PATCH BUGFIX -rc4] Smack: Respect 'unlabeled' netlabel mode Ahmed S. Darwish
2008-05-30 23:10 ` Casey Schaufler
2008-05-31 0:58 ` Ahmed S. Darwish
2008-05-31 0:37 ` Casey Schaufler
2008-05-31 13:08 ` Paul Moore
2008-05-30 23:57 ` [PATCH BUGFIX -v2 " Ahmed S. Darwish
2008-05-30 23:10 ` Tetsuo Handa
2008-05-30 23:25 ` Andrew Morton [this message]
2008-05-31 1:12 ` Ahmed S. Darwish
2008-05-30 23:45 ` Casey Schaufler
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