Re: [PATCH 6/6] xen-netback: don't disconnect frontend when seeing oversize frame
From: Wei Liu <hidden>
Date: 2013-03-25 12:00:09
From: Wei Liu <hidden>
Date: 2013-03-25 12:00:09
On Mon, Mar 25, 2013 at 11:47:17AM +0000, David Vrabel wrote:
On 25/03/13 11:08, Wei Liu wrote:quoted
Some buggy frontends may generate frames larger than 64 KiB. We should aggresively consume all slots and drop the packet instead of disconnecting the frontend.The following is the changeset description I wrote internally. It's a bit more descriptive. Apologies for not sending out a proper patch in the first place. "Some frontend drivers are sending packets >= 64 KiB in length. This length overflows the length field in the first frag making the following frags have an invalid length ("Frag is bigger than frame"). Turn this error back into a non-fatal error by dropping the packet. To avoid having the following frags having fatal errors, consume all frags in the packet. This does not reopen the security hole as if the packet as an invalid number of frags it will still hit this fatal error case."
Thanks. Overall this looks good. I will need to change 'frags' to 'slots' though. Wei.
David