netdev - Re: cassini driver skb->truesize bug

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: <1196850226.9713.33.camel@bzorp.balabit>
Date:	Wed, 05 Dec 2007 11:23:46 +0100
From:	Balazs Scheidler <bazsi@...abit.hu>
To:	panther@...abit.hu
Cc:	netdev@...r.kernel.org
Subject: Re: cassini driver skb->truesize bug

Some more investigation revealed that the cassini driver leaks the data
portion of all RXed packets, this makes the driver completely unusable.

We've tested the following combinations:
 * 2.6.17 (patched, but no cassini related patches)
 * 2.6.22 Ubuntu Gutsy.

It still worked in 2.6.12 where we originally backported the driver from
2.6.14.

The sk_buff count in slabinfo stays normal, so the skbs are properly
freed. I'm suspicious about all this cas_page_t wrappers.

Is there a maintainer for this driver? All our previous questions went
unanswered.


On Tue, 2007-12-04 at 15:19 +0100, Laszlo Attila Toth wrote:
> Hello,
> 
> we got the following message:
> SKB BUG: Invalid truesize (376) len=514, sizeof(sk_buff)=248
> 
> It only occurs on larger traffic (at speed 100 Mbps: always), but  not 
> when downloading a small web page.
> 
> In cas_rx_process_pkt() the the skb's truesize is only set via skb_put()
> but it is not used if there are fragments, also skb->len is increased by
> the fragment's size, but the truesize member is unchanged. I compared it 
> to the implementation in e1000 where  all of the len, datalen and 
> trusize members are increased.
> 
> If I modify the code to add the fragment's size to the truesize member, 
> the driver allocates all available memory after a while.
> 
> Regards,
> Attila
> --
> 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
> 
-- 
Bazsi

--
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