linux-kernel - Re: [PATCH] wireless: wext: allocate space for NULL-termination for 32byte SSIDs

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]

Date:	Tue, 15 Dec 2009 11:31:23 +0100
From:	Johannes Berg <johannes@...solutions.net>
To:	Daniel Mack <daniel@...aq.de>
Cc:	David Miller <davem@...emloft.net>, linux-kernel@...r.kernel.org,
	dcbw@...hat.com, m.hirsch@...mfeld.com, netdev@...r.kernel.org,
	libertas-dev@...ts.infradead.org, stable@...nel.org,
	linux-wireless@...r.kernel.org
Subject: Re: [PATCH] wireless: wext: allocate space for NULL-termination
 for 32byte SSIDs

On Tue, 2009-12-15 at 18:20 +0800, Daniel Mack wrote:

> > > Since you indicate the kernel crashed, it is likely that libertas is
> > > treating the buffer as a string, instead of an SSID.
> 
> Ok, I dodn't know that - thanks for pointing it out. In my setup here,
> SSIDs are always valid alphanumeric strings, and I was mislead by the
> comment that mentions the NULL-termination.

Yeah ... that's an unfortunate historic mistake in wireless extensions
that we try to fix up there. It cannot always be successfully fixed up,
but the NUL-termination is nothing that anything but this code should be
worried about or rely on.

> > drivers/net/wireless/libertas$ grep lbs_deb_ * | grep ssid|grep '%s'
> > assoc.c:	lbs_deb_join("current SSID '%s', ssid length %u\n",
> > assoc.c:	lbs_deb_join("requested ssid '%s', ssid length %u\n",
> > assoc.c:	lbs_deb_join("ADHOC_START: SSID '%s', ssid length %u\n",
> > scan.c:		lbs_deb_wext("set_scan, essid '%s'\n",
> 
> Those macros are stubbed out as nops in my setup, so they can
> unfortunately not be the reason. I'll dig deeper :)

Well, the stack trace ought to help.

johannes

Download attachment "signature.asc" of type "application/pgp-signature" (802 bytes)