Re: [PATCH net-next v2] net: ipv6: seg6: report lwtunnel setup errors via extack

[Gabriel Goller]

On 22.09.2026 23:49, Andrea Mayer wrote:
> On Tue, 22 Sep 2026 11:08:33 +0200
> Gabriel Goller <g.goller@xxxxxxxxxxx> wrote:
> 
> Hi Gabriel,
> 
> > seg6_build_state() rejected invalid configurations with a generic -EINVAL, so
> > "ip route add ... encap seg6 ..." always reported "Invalid argument".
> > 
> > Attach an extack message to each of them. The checks themselves and their return
> > values are unchanged.
> > 
> > Signed-off-by: Gabriel Goller <g.goller@xxxxxxxxxxx>
> 
> The commit message stays in the changelog, so wrapping the body at 75
> columns would be better.

Done, thanks.

> > ---
> > 
> > v2 (https://lore.kernel.org/netdev/20260918153544.1178884-1-g.goller@xxxxxxxxxxx/):
> >  * dropped tests
> > 
> >  net/ipv6/seg6_iptunnel.c | 25 ++++++++++++++++++++-----
> >  1 file changed, 20 insertions(+), 5 deletions(-)
> > 
> > diff --git a/net/ipv6/seg6_iptunnel.c b/net/ipv6/seg6_iptunnel.c
> > index 61c6a27bf202..e7f75970e26e 100644
> > --- a/net/ipv6/seg6_iptunnel.c
> > +++ b/net/ipv6/seg6_iptunnel.c
> > @@ -756,8 +756,12 @@ static int seg6_build_state(struct net *net, struct nlattr *nla,
> >  	struct seg6_lwt *slwt;
> >  	int err;
> >  
> > -	if (family != AF_INET && family != AF_INET6)
> > +	if (family != AF_INET && family != AF_INET6) {
> > +		NL_SET_ERR_MSG(
> > +			extack,
> > +			"unsupported address family for SRv6 encapsulation");
> >  		return -EINVAL;
> > +	}
> 
> checkpatch flags this line ("Lines should not end with a '('"). The
> two-line form used in the rest of the file would be better:
> 
> 	NL_SET_ERR_MSG(extack,
> 		       "unsupported address family for SRv6 encapsulation");
> 
> The string goes a bit over 80 columns but should stay on one line for grep.

Fixed this.

Thanks for the review!
Gabriel

> A side note: the source_inline bot failure looks like a false positive,
> the script matches "inline" inside the string literal.
> 
> Thanks,
> Andrea
> 
>