netdev - Re: [PATCH 7/7] xen-netback: don't disconnect frontend when seeing oversize packet

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20130409115419.GE16998@zion.uk.xensource.com>
Date:	Tue, 9 Apr 2013 12:54:19 +0100
From:	Wei Liu <wei.liu2@...rix.com>
To:	David Laight <David.Laight@...LAB.COM>
CC:	Wei Liu <wei.liu2@...rix.com>,
	"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
	"xen-devel@...ts.xen.org" <xen-devel@...ts.xen.org>,
	Ian Campbell <Ian.Campbell@...rix.com>,
	David Vrabel <david.vrabel@...rix.com>,
	"konrad.wilk@...cle.com" <konrad.wilk@...cle.com>,
	"annie.li@...cle.com" <annie.li@...cle.com>,
	"wdauchy@...il.com" <wdauchy@...il.com>
Subject: Re: [PATCH 7/7] xen-netback: don't disconnect frontend when seeing
 oversize packet

On Tue, Apr 09, 2013 at 12:34:42PM +0100, David Laight wrote:
> > +		if (!drop_err && txp->size > first->size) {
> > +			if (net_ratelimit())
> > +				netdev_dbg(vif->dev,
> > +					   "Packet is bigger than frame.\n");
> 
> It must be worth printing txp->size and first->size here.
> Similarly for the other errors in the other patches.
> 

Sure.

> Probably difficult for some of these errors, but it is
> sometimes worth saving the last 'bad' item. So that with
> an appropriate tool (maybe hexdump of /dev/kmem) it is
> possible to look at the actual contents and thus determine
> the actual source of the error.
> 

I doubt that you can get much information by analysing txp, it is just
controll structure in ring, not the actual packet content. The packet is
still in DomU.


Wei.

> 	David
> 
--
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