netdev - Re: Fwd: UBSAN: array-index-out-of-bounds in net/wireless/nl80211.c and net/mac80211/scan.c

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: <161df39ee89ae640828d3226a8de3d60f786ddd7.camel@sipsolutions.net>
Date: Thu, 09 May 2024 12:52:56 +0200
From: Johannes Berg <johannes@...solutions.net>
To: Jannik Glückert <jannik.glueckert@...il.com>
Cc: Bagas Sanjaya <bagasdotme@...il.com>, Linux Kernel Mailing List
 <linux-kernel@...r.kernel.org>, Linux Networking <netdev@...r.kernel.org>, 
 Linux Wireless <linux-wireless@...r.kernel.org>, Jouni Malinen
 <jouni.malinen@...eros.com>, "John W. Linville" <linville@...driver.com>,
 Kalle Valo <kvalo@...nel.org>, Emmanuel Grumbach
 <emmanuel.grumbach@...el.com>, "David S. Miller" <davem@...emloft.net>,
 Eric Dumazet <edumazet@...gle.com>, Jakub Kicinski <kuba@...nel.org>, Paolo
 Abeni <pabeni@...hat.com>,  Sam James <sam@...too.org>
Subject: Re: Fwd: UBSAN: array-index-out-of-bounds in net/wireless/nl80211.c
 and net/mac80211/scan.c

On Thu, 2024-05-09 at 12:49 +0200, Jannik Glückert wrote:
> 
> > (Seriously. If you're running with bleeding edge toolchains that pretty
> > much nobody has yet, send patches.)
> 
> I'm not sure what to make of this - this bug has been around ever
> since the code was added, modern toolchains just happen to be one way
> to expose it.

No, that's incorrect. This is perfectly valid code:

 struct x {
   int n;
   int a[] /* __counted_by(n) */;
 };

 x = alloc(sizeof(*x) + sizeof(int) * 2);
 x->a[0] = 10;
 x->a[1] = 20;
 x->n = 2;

However, the uncommenting of the __counted_by() annotation will lead to
a complaint.

johannes