On Mon, Jan 22, 2018 at 12:14 PM, David Miller <da...@davemloft.net> wrote: > From: Pravin Shelar <pshe...@ovn.org> > Date: Fri, 19 Jan 2018 13:54:15 -0800 > >> I agree it is not perfect. But the other proposed patch does not fix >> the connectivity issue. It only adds log msg in such cases at cost >> of extra checks/code. Therefore I prefer the easier fix for the >> issue which also fixes for all cases of packet forwarding rather >> than just OVS and Bridge. > > I really think that something needs to guarantee that device drivers > will never be given either over-MTU or over-max-GSO-seg-size SKBs. > > Otherwise drivers need to add completely stupid checks like making > sure that SKB lengths do not exceed the maxmimu value that can be > encoded into descriptors. > > What's probably happening often now in such situations is that the > driver ends up masking the length blindly and ends up sending out a > truncated packet. > > Which frankly is quite bad too. > > It doesn't scale to add these checks into every driver, or trying to > "figure out" which drivers will behave adversely and only add checks > to those. > > The kernel shouldn't pass objects with out-of-range attributes > to the driver, period.
OK, in that case we could add a check in validate_xmit_skb() as done by Daniel in a patch posted earlier.
