RE: [PATCH] usb: gadget: aspeed: fix buffer overflow

[Neal Liu <neal_liu@aspeedtech.com>]

> > On Fri, Oct 28, 2022 at 09:55:57AM +0000, Neal Liu wrote:
> > > > > > > Thanks for your feedback.
> > > > > > > I tried to reproduce it on my side, and it cannot be reproduce it.
> > > > > > > Here are my test sequences:
> > > > > > > 1. emulate one of the vhub port to usb ethernet through
> > > > > > > Linux gadget
> > > > > > > (ncm)
> > > > > >
> > > > > > We are using rndis instead of ncm.
> > > > > >
> > > > > > > 2. connect BMC vhub to Host
> > > > > > > 3. BMC & Host can ping each other (both usb eth dev default
> > > > > > > mtu is
> > > > > > > 1500) 4. Set BMC mtu to 1000 (Host OS cannot set usb eth dev
> > > > > > > mtu to 2000, it's maxmtu is 1500)
> > > > > >
> > > > > > Not sure if it's related, but in my case (USB rndis, Debian 10
> > > > > > OS) it should be able to set MTU to 2000.
> > > > >
> > > > > Using rndis is able to set MTU to 2000, and the issue can be
> reproduced.
> 
> USB ecm is also tested and it is possible to set MTU to 2000, and could
> reproduce the issue.
> So I think this patch is needed anyway.
> 
> @Neal Liu Could you kindly help to verify the USB ECM case?

How to set MTU to 2000 on USB ECM case? I remember last time I cannot set by using "ifconfig ..."
Regardless ECM or RNDIS, I agree this patch is still needed.

> > > >
> > > > Please NEVER use rndis anymore.  I need to go just delete that
> > > > driver from the tree.
> > > >
> > > > It is insecure-by-design and will cause any system that runs it to
> > > > be instantly compromised and it can not be fixed.  Never trust it.
> > > >
> > > > Even for data throughput tests, I wouldn't trust it as it does odd
> > > > things with packet sizes as you show here.
> > >
> > > Thanks for the info, Greg.
> > > If rndis will no longer be supported, how to use usb-ethernet on Windows
> OS?
> > > For my understanding, ncm/ecm cannot work on Windows OS.
> >
> > rndis should ONLY be there for Windows XP, which is long out-of-support.
> > Newer versions of windows have more sane usb protocols built into it
> > and this driver is not needed.
> >
> > As proof of this, Android devices removed this from their kernel
> > configuration a few years ago and no one has complained :)
> >
> > thanks,
> >
> > greg k-h