netdev - Re: [PATCH 03/10] net/fec: add mac field into platform data and consolidate fec_get

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: <20101229124220.GD14221@pengutronix.de>
Date:	Wed, 29 Dec 2010 13:42:21 +0100
From:	Uwe Kleine-König 
	<u.kleine-koenig@...gutronix.de>
To:	Shawn Guo <shawn.guo@...escale.com>
Cc:	Baruch Siach <baruch@...s.co.il>, davem@...emloft.net,
	gerg@...pgear.com, eric@...rea.com, bryan.wu@...onical.com,
	r64343@...escale.com, B32542@...escale.com, lw@...o-electronics.de,
	w.sang@...gutronix.de, s.hauer@...gutronix.de,
	linux-arm-kernel@...ts.infradead.org, netdev@...r.kernel.org
Subject: Re: [PATCH 03/10] net/fec: add mac field into platform data and
	consolidate fec_get_mac

Hello Shawn,

On Wed, Dec 29, 2010 at 07:58:09PM +0800, Shawn Guo wrote:
> On Wed, Dec 29, 2010 at 11:31:38AM +0100, Uwe Kleine-König wrote:
> > On Wed, Dec 29, 2010 at 06:05:21PM +0800, Shawn Guo wrote:
> > > On Wed, Dec 29, 2010 at 08:53:30AM +0200, Baruch Siach wrote:
> > > 	if (iap == fec_mac_default)
> > > 		dev->dev_addr[ETH_ALEN-1] = fec_mac_default[ETH_ALEN-1] + fep->pdev->id;
> > Can this overflow?  (I didn't check the code, so my concern might be
> > completely stupid here.)
> No. dev->dev_addr points to netdev_hw_addr->addr, which is a 32 bytes array.
I didn't mean an out-of-bound access, but what is if
fec_mac_default[ETH_ALEN-1] is 0xff and you add 1?  Does that result in
0x100 or 0?  What if id is <0?  For big ids you might even handle a
carry to indixes <ETH_ALEN-2.

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html