Re: [PATCH 5.10 173/563] xfrm: interface with if_id 0 should return error

[Steffen Klassert]

On Wed, Jan 26, 2022 at 10:59:37PM +0100, Pavel Machek wrote:
> Hi!
> 
> > [ Upstream commit 8dce43919566f06e865f7e8949f5c10d8c2493f5 ]
> > 
> > xfrm interface if_id = 0 would cause xfrm policy lookup errors since
> > Commit 9f8550e4bd9d.
> > 
> > Now explicitly fail to create an xfrm interface when if_id = 0
> 
> This will break changelink completely, AFAICT.
> 
> > @@ -672,7 +677,12 @@ static int xfrmi_changelink(struct net_device *dev, struct nlattr *tb[],
> >  {
> >  	struct xfrm_if *xi = netdev_priv(dev);
> >  	struct net *net = xi->net;
> > -	struct xfrm_if_parms p;
> > +	struct xfrm_if_parms p = {};
> > +
> > +	if (!p.if_id) {
> > +		NL_SET_ERR_MSG(extack, "if_id must be non zero");
> > +		return -EINVAL;
> > +	}
> >  
> >  	xfrmi_netlink_parms(data, &p);
> >  	xi = xfrmi_locate(net, &p);
> 
> if_id will be always 0, because it was not yet initialized.
> 
> Best regards,
> 									Pavel
> 
> Signed-off-by: Pavel Machek <pavel@xxxxxxx>

Can you please resend this with proper commit message and 'Fixes:' tag?

Thanks!