linux-kernel - Re: [PATCH] dmaengine: pxa_dma: Prefer struct

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <20211020233233.GA1320242@embeddedor>
Date:   Wed, 20 Oct 2021 18:32:33 -0500
From:   "Gustavo A. R. Silva" <gustavoars@...nel.org>
To:     "Gustavo A. R. Silva" <gustavo@...eddedor.com>
Cc:     Len Baker <len.baker@....com>, Daniel Mack <daniel@...que.org>,
        Haojian Zhuang <haojian.zhuang@...il.com>,
        Robert Jarzmik <robert.jarzmik@...e.fr>,
        Vinod Koul <vkoul@...nel.org>,
        Kees Cook <keescook@...omium.org>,
        linux-arm-kernel@...ts.infradead.org, dmaengine@...r.kernel.org,
        linux-hardening@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] dmaengine: pxa_dma: Prefer struct_size over open coded
 arithmetic

On Mon, Sep 20, 2021 at 07:00:58PM -0500, Gustavo A. R. Silva wrote:
> 
> 
> On 9/18/21 05:40, Len Baker wrote:
> > As noted in the "Deprecated Interfaces, Language Features, Attributes,
> > and Conventions" documentation [1], size calculations (especially
> > multiplication) should not be performed in memory allocator (or similar)
> > function arguments due to the risk of them overflowing. This could lead
> > to values wrapping around and a smaller allocation being made than the
> > caller was expecting. Using those allocations could lead to linear
> > overflows of heap memory and other misbehaviors.
> > 
> > So, use the struct_size() helper to do the arithmetic instead of the
> > argument "size + count * size" in the kzalloc() function.
> > 
> > [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments
> > 
> > Signed-off-by: Len Baker <len.baker@....com>
> 
> Reviewed-by: Gustavo A. R. Silva <gustavoars@...nel.org>

I'm taking this in my -next tree.

Thanks
--
Gustavo