linux-kernel - Re: BUG in rt2x00lib_txdone() with 2.6.37-rc8

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: <AANLkTimMVdsGONSD9OmnX2eJk51H5Pzj4K8irHa=E-qx@mail.gmail.com>
Date:	Sat, 15 Jan 2011 14:34:11 +0100
From:	Ivo Van Doorn <ivdoorn@...il.com>
To:	Helmut Schaa <helmut.schaa@...glemail.com>
Cc:	Ingo Brunberg <ingo_brunberg@....de>, linux-kernel@...r.kernel.org,
	linux-wireless@...r.kernel.org
Subject: Re: BUG in rt2x00lib_txdone() with 2.6.37-rc8

Hi,

> Just a shot in the dark but since the stack trace shows the newly added
> watchdog this might be the result of a race between a regular txdone work
> (mac80211 workqueue) vs the watchdog work (global workqueue).
>
> I guess the following situation could happen:
> A regular tx done work calls rt2x00lib_txdone which first sets entry->skb to
> NULL, calls the driver specific clear_entry and afterwards increases
> Q_INDEX_DONE. If the watchdog work calls rt2x00lib_txdone on a different CPU
> inbetween the skb might be NULL and cause the above oops.

This could be, would be interesting to know if compat-wireless also shows
this problem. Because the queue refactoring code which should have solved
these race conditions was added after 2.6.37.

Ivo
--
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/