[PATCH net v2 1/1] net: stmmac: Prevent DSA tags from breaking COE on stmmac

[Romain Gantois]

Hi Linus,

On Tue, 2 Jan 2024, Linus Walleij wrote:
...
> > +static inline bool stmmac_has_ip_ethertype(struct sk_buff *skb)
> > +{
> > +       __be16 proto = eth_header_parse_protocol(skb);
> 
> I made a new function for this in my patch
> https://lore.kernel.org/netdev/20231222-new-gemini-ethernet-regression-v4-2-a36e71b0f32b@linaro.org/
> 
> I was careful to add if (!pskb_may_pull(skb, ETH_HLEN)) because Eric
> was very specific about this, I suppose you could get fragment frames that
> are smaller than an ethernet header.

Okay nice, then I'll rewrite this series to use the new function once your 
changes make it in.

> Should we add an if (!pskb_may_pull(skb, ETH_HLEN)) to
> eth_header_parse_protocol()?
That does sound logical to me but I couldn't tell you what the impact on current 
callers would be. The net maintainers will probably have a better idea of this.

Best Regards,

-- 
Romain Gantois, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com