linux-kernel - Re: [ 08/12] mac80211: zero initialize count field in ieee80211_tx

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 for Android: free password hash cracker in your pocket

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

Message-ID: <20120312063108.GC8971@1wt.eu>
Date:	Mon, 12 Mar 2012 07:31:08 +0100
From:	Willy Tarreau <w@....eu>
To:	Ben Hutchings <ben@...adent.org.uk>
Cc:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	Pavel Roskin <proski@....org>,
	Mohammed Shafi Shajakhan <mohammed@....qualcomm.com>,
	"John W. Linville" <linville@...driver.com>
Subject: Re: [ 08/12] mac80211: zero initialize count field in ieee80211_tx_rate

On Mon, Mar 12, 2012 at 01:57:52AM +0000, Ben Hutchings wrote:
> On Mon, 2012-03-12 at 01:20 +0100, Willy Tarreau wrote:
> > 2.6.32-longterm review patch.  If anyone has any objections, please let me know.
> > 
> > ------------------
> > 
> > From: Mohammed Shafi Shajakhan <mohammed@....qualcomm.com>
> > 
> > commit 8617b093d0031837a7be9b32bc674580cfb5f6b5 upstream.
> > 
> > rate control algorithms concludes the rate as invalid
> > with rate[i].idx < -1 , while they do also check for rate[i].count is
> > non-zero. it would be safer to zero initialize the 'count' field.
> > recently we had a ath9k rate control crash where the ath9k rate control
> > in ath_tx_status assumed to check only for rate[i].count being non-zero
> > in one instance and ended up in using invalid rate index for
> > 'connection monitoring NULL func frames' which eventually lead to the crash.
> > thanks to Pavel Roskin for fixing it and finding the root cause.
> > https://bugzilla.redhat.com/show_bug.cgi?id=768639
> 
> In 2.6.32, ath_tx_status() checks that rates[i].idx >= 0, so it properly
> ignores these dummy entries.  Further, there is code further down the
> rate_control_get_rate() function that sets .idx only and appears to
> depend on the initialisation of .count = 1.
> 
> So I'm pretty sure this patch is wrong for 2.6.32; it could be
> backported but I don't think the change is necessary anyway.

Dropping it then, thanks Ben !

Willy

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