netdev - Re: [PATCH 2/4 v3 net-next] net: stmmac: adding multiple buffers for rx

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

Message-ID: <20170406123217.GB5115@ulmo.ba.sec>
Date:   Thu, 6 Apr 2017 14:32:17 +0200
From:   Thierry Reding <treding@...dia.com>
To:     Joao Pinto <Joao.Pinto@...opsys.com>
CC:     <davem@...emloft.net>, <clabbe.montjoie@...il.com>,
        <niklas.cassel@...s.com>, <julia.lawall@...6.fr>,
        <netdev@...r.kernel.org>
Subject: Re: [PATCH 2/4 v3 net-next] net: stmmac: adding multiple buffers for
 rx

On Thu, Apr 06, 2017 at 09:49:09AM +0100, Joao Pinto wrote:
[...]
>  err_init_rx_buffers:
> -	while (--i >= 0)
> -		stmmac_free_rx_buffer(priv, i);
> +	while (queue >= 0) {

I /think/ this could simply be:

	while (queue--) {
		...
	}

That evaluates before the decrement and hence properly deals with the
case of 0. The difference to your code is that it will skip the first
iteration, but I think that's fine because stmmac_init_rx_buffers()
already cleans up properly, so the queue'th element doesn't have to
be freed again.

Anyway, I think your version will work just as well.

Thierry

Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)