Re: [PATCH net-next V6] net: Variable SLAAC: SLAAC with prefixes of arbitrary length in PIO

[Dmytro Shytyi <dmytro@shytyi.net>]

---- On Thu, 19 Nov 2020 19:44:13 +0100 Jakub Kicinski <kuba@kernel.org> wrote ----

 > On Thu, 19 Nov 2020 14:37:35 +0100 Dmytro Shytyi wrote: 
 > > +struct inet6_ifaddr *ipv6_cmp_rcvd_prsnt_prfxs(struct inet6_ifaddr *ifp, 
 > > +                           struct inet6_dev *in6_dev, 
 > > +                           struct net *net, 
 > > +                           const struct prefix_info *pinfo) 
 > > +{ 
 > > +    struct inet6_ifaddr *result_base = NULL; 
 > > +    struct inet6_ifaddr *result = NULL; 
 > > +    struct in6_addr curr_net_prfx; 
 > > +    struct in6_addr net_prfx; 
 > > +    bool prfxs_equal; 
 > > + 
 > > +    result_base = result; 
 > > +    rcu_read_lock(); 
 > > +    list_for_each_entry_rcu(ifp, &in6_dev->addr_list, if_list) { 
 > > +        if (!net_eq(dev_net(ifp->idev->dev), net)) 
 > > +            continue; 
 > > +        ipv6_addr_prefix_copy(&net_prfx, &pinfo->prefix, pinfo->prefix_len); 
 > > +        ipv6_addr_prefix_copy(&curr_net_prfx, &ifp->addr, pinfo->prefix_len); 
 > > +        prfxs_equal = 
 > > +            ipv6_prefix_equal(&net_prfx, &curr_net_prfx, pinfo->prefix_len); 
 > > +        if (prfxs_equal && pinfo->prefix_len == ifp->prefix_len) { 
 > > +            result = ifp; 
 > > +            in6_ifa_hold(ifp); 
 > > +            break; 
 > > +        } 
 > > +    } 
 > > +    rcu_read_unlock(); 
 > > +    if (result_base != result) 
 > > +        ifp = result; 
 > > +    else 
 > > +        ifp = NULL; 
 > > + 
 > > +    return ifp; 
 > > +} 
 >  
 > Thanks for adding the helper! Looks like it needs a touch up: 
 
Understood. Thank you for pointing this out. I think I did not catch this warning as my Makefile didn't include "-Wmissing-prototypes"

 > net/ipv6/addrconf.c:2579:22: warning: no previous prototype for ‘ipv6_cmp_rcvd_prsnt_prfxs’ [-Wmissing-prototypes] 
 >  2579 | struct inet6_ifaddr *ipv6_cmp_rcvd_prsnt_prfxs(struct inet6_ifaddr *ifp, 
 >  |                      ^~~~~~~~~~~~~~~~~~~~~~~~~ 
 > net/ipv6/addrconf.c:2579:21: warning: symbol 'ipv6_cmp_rcvd_prsnt_prfxs' was not declared. Should it be static? 
 > 

Hideaki Yoshifuji helped to improve this patch with suggestions. @Hideaki, should I add "Reported-by" tag in this case?
Jakub Kicinski also helped to find errors and help with improvement. @Jakub, should I add "Reported-by" tag in this case? 

Thanks,
Dmytro SHYTYI