lkml.org 
[lkml]   [2013]   [Nov]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH] rds: fix local ping DoS
From
From: Josh Hunt <johunt@akamai.com>
Date: Wed, 13 Nov 2013 17:15:43 -0800

> The rds_ib_xmit function in net/rds/ib_send.c in the Reliable Datagram Sockets
> (RDS) protocol implementation allows local users to cause a denial of service
> (BUG_ON and kernel panic) by establishing an RDS connection with the source
> IP address equal to the IPoIB interface's own IP address, as demonstrated by
> rds-ping.
>
> A local unprivileged user could use this flaw to crash the system.
>
> CVE-2012-2372
>
> Reported-by: Honggang Li <honli@redhat.com>
> Signed-off-by: Josh Hunt <johunt@akamai.com>

I'm sorry I can't apply this. This commit message needs to be much
less terse and explain things more.

First of all, why is the "off % RDS_FRAG_SIZE" important?

And, even more importantly, why is is OK to avoid this assertion just
because we're going over loopback?

Furthermore, why doesn't net/rds/iw_send.c:rds_iw_xmit() have the same
exact problem? It makes the same exact assertion check.

I know this RDS code is a steaming pile of poo, but that doesn't mean
we just randomly adjust assertions to make crashes go away without
sufficient understanding of exactly what's going on.

Thanks.


\
 
 \ /
  Last update: 2013-11-14 08:41    [W:0.127 / U:0.168 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site