Re: WARNING in dln2_start_rx_urbs/usb_submit_urb

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Dec 09, 2019 at 12:26:04PM +0000, Lee Jones wrote:
> On Wed, 20 Nov 2019, Oliver Neukum wrote:
> 
> > #syz test: https://github.com/google/kasan.git b1aa9d83
> > 
> > From 6f3de1e2c53fcee54d90a6891df9cea763eca86b Mon Sep 17 00:00:00 2001
> > From: Oliver Neukum <oneukum@suse.com>
> > Date: Wed, 20 Nov 2019 16:15:13 +0100
> > Subject: [PATCH] mfd: dln2: more sanity checking for endpoints
> > 
> > It is not enough to check for the number of endpoints.
> > The types must also be correct.
> > 
> > Reported-by: syzbot+48a2851be24583b864dc@syzkaller.appspotmail.com
> > Signed-off-by: Oliver Neukum <oneukum@suse.com>
> > ---
> >  drivers/mfd/dln2.c | 13 +++++++++++--
> >  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> Looks okay in principle.
> 
> It would be great if one of the USB guys could take a quick look.
> 
> Is this not something that could be done at a subsystem level?

We have functions in the USB core for this, look at
usb_find_common_endpoints() for an example of this.  You can convert the
driver to use this, or use the usb helper functions that Oliver is using
here in a much simpler patch :)

thanks,

greg k-h