Re: [Xen-devel] [0/5] [NET]: Add TSO support

[Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>]

On Thu, Jun 29, 2006 at 11:32:43AM +0100, Keir Fraser wrote:
> 
> What if gso_segs, or any other gso parameter (e.g., type), is set 
> incorrectly? The backend cannot trust frontend clients, so I'm rather 
> worried that we could make the backend network stack crash!

gso_type is a key so the OS (Linux) must deal with all possible values.
Any packet with a protocol or feature bit that it does not recognise
will be dropped.

However, you have a very good point regarding gso_segs.  I'll change it
so that it is always recalculated for SKB_GSO_DODGY packets.

> Also we should probably only define a XEN_GSO_TCPV4 flag for now, since 
> we support only plain TSO right now. No skbuffs should get passed to 
> netfront that have other GSO flags set, right? Seince we only advertise 
> NETIF_F_TSO.

While it shouldn't have any adverse effects for the reason above, I will
add a mask so that only bits in the mask are allowed through to gso_type.

Cheers,
-- 
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Email: Herbert Xu ~{PmV>HI~} <herbert@xxxxxxxxxxxxxxxxxxx>
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