Date: Tue, 14 Feb 2012 09:07:44 -0600 (CST)
From: Christoph Lameter <cl@linux.com>
To: Andrew Morton <akpm@linux-foundation.org>
cc: Yang Bai <hamo.by@gmail.com>, penberg@kernel.org, mpm@selenic.com,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] slab: warning if total alloc size overflow
In-Reply-To: <20120214005301.a9d5be1a.akpm@linux-foundation.org>
Message-ID: <alpine.DEB.2.00.1202140906500.20013@router.home>
References: <1329204499-2671-1-git-send-email-hamo.by@gmail.com> <20120214005301.a9d5be1a.akpm@linux-foundation.org>
User-Agent: Alpine 2.00 (DEB 1167 2008-08-23)
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 624
Lines: 16

On Tue, 14 Feb 2012, Andrew Morton wrote:

> One of the applications of kcalloc() is to prevent userspace from
> causing a multiplicative overflow (and then perhaps causing an
> overwrite beyond the end of the allocated memory).
>
> With this patch, we've just handed the user a way of spamming the logs
> at 1MHz.  This is bad.

Well there is WARN_ON_ONCE too to prevent that.

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