netdev - Re: [PATCH net] net: usbnet: prevent buggy devices from killing us

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:	Fri, 25 Jan 2013 08:13:15 +0100
From:	Bjørn Mork <bjorn@...k.no>
To:	Oliver Neukum <oliver@...kum.org>
Cc:	linux-usb@...r.kernel.org, netdev@...r.kernel.org
Subject: Re: [PATCH net] net: usbnet: prevent buggy devices from killing us

Oliver Neukum <oliver@...kum.org> writes:
> On Thursday 24 January 2013 20:16:56 Bjørn Mork wrote:
>> A device sending 0 length frames as fast as it can has been
>> observed killing the host system due to the resulting memory
>> pressure.
>> 
>> Temporarily disable RX skb allocation and URB submission when
>> the current error ratio is high, preventing us from trying to
>> allocate an infinite number of skbs.  Reenable as soon as we
>> are finished processing the done queue, allowing the device
>> to continue working after short error bursts.
>> 
>> Signed-off-by: Bjørn Mork <bjorn@...k.no>
>> ---
>> So is this starting to look OK?
>
> It seems to me that we at least need to try some error recovery.

Won't the disabling code in usbnet_bh do? RX will only stay disabled
until the done queue is handled.

> How about resetting the device when it is no longer used?

Yes, that we should do. I guess usbnet_open is the place to reset the
flag and counters? I'll send another version taking care of this and
Joes comment.


Bjørn
--
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