Re: [PATCH 4.19 23/37] ipv4: Update exception handling for multipath routes via same device

[Greg Kroah-Hartman]

On Fri, Sep 25, 2020 at 06:51:34PM +0200, Pavel Machek wrote:
> Hi!
> 
> > [ Upstream commit 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 ]
> > 
> > Kfir reported that pmtu exceptions are not created properly for
> > deployments where multipath routes use the same device.
> 
> This is mismerged (in a way that does not affect functionality):
> 
> 
> > @@ -779,6 +779,8 @@ static void __ip_do_redirect(struct rtab
> >  			if (fib_lookup(net, fl4, &res, 0) == 0) {
> >  				struct fib_nh *nh = &FIB_RES_NH(res);
> >  
> > +				fib_select_path(net, &res, fl4, skb);
> > +				nh = &FIB_RES_NH(res);
> >  				update_or_create_fnhe(nh, fl4->daddr, new_gw,
> >  						0, false,
> 
> nh is assigned value that is never used. Mainline patch removes the
> assignment (but variable has different type).
> 
> 4.19 should delete the assignment, too.

Ah, good catch, I'll merge this in, thanks.

greg k-h