[lkml]   [2002]   [Apr]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: AW: Re: AW: Re: VLAN and Network Drivers 2.4.x
    On Wed, Apr 24, 2002 at 11:04:47AM -0700, Ben Greear wrote:
    > Jeff Garzik wrote:
    > > On Wed, Apr 24, 2002 at 10:31:29AM -0700, Ben Greear wrote:
    > >
    > >>Also, is there any good reason that we can't get at least a compile
    > >>time change into some of the drivers like tulip where we know we can
    > >>get at least MOST of the cards supported with a small change?
    > >>
    > >
    > > The tulip patch is butt-ugly - the oversized allocation isn't needed,
    > > and it just flat-out turns off large packet protection. That's really
    > > not what you want to do, even for the best tulip cards. If an oversized
    > > gram (non-VLAN) makes it into a network which such a patched tulip
    > > driver, you can DoS. So, I view the current tulip patch as unacceptable
    > > too -- for security reasons, we should not even take it as a compile
    > > time patch. (and I recommend against using that patch on production
    > > machines, for the same security reasons)
    > I can DOS a tulip card with very small packets too ;)

    A tulip card? Or the stack?

    Can you DoS it when CONFIG_NET_HW_FLOWCONTROL is enabled?
    That's basically NAPI without the fancy acronym...

    > > The proper tulip patch does not need to change packet allocation size
    > > at all (it's already plenty big enough), and it needs to copy the RX
    > > fragment handling code from 8139cp (which is admittedly ugly, slow path)
    > > or write fresh fragment handling code. Along with that fragment
    > > handling code comes a safe way to do VLAN, and non-standard large MTUs
    > > in general.
    > In the general case, where the packets are only 1518 (ie no DoS or mis-configured
    > hardware is in effect), is there a need for the "ugly, slow path" code to run?

    It depends on the chip, but most generally: no


    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    More majordomo info at
    Please read the FAQ at

     \ /
      Last update: 2005-03-22 13:25    [W:0.022 / U:1.340 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site