Re: [PATCH v2] net: Fix behaviour of unreachable, blackhole and prohibit routes

[Florian Westphal <fw@strlen.de>]

Nikola Forró <nforro@redhat.com> wrote:
> Man page of ip-route(8) says following about route types:
> 
>   unreachable - these destinations are unreachable.  Packets are dis‐
>   carded and the ICMP message host unreachable is generated.  The local
>   senders get an EHOSTUNREACH error.
> 
>   blackhole - these destinations are unreachable.  Packets are dis‐
>   carded silently.  The local senders get an EINVAL error.
> 
>   prohibit - these destinations are unreachable.  Packets are discarded
>   and the ICMP message communication administratively prohibited is
>   generated.  The local senders get an EACCES error.
> 
> In the inet6 address family, this was correct, except the local senders
> got ENETUNREACH error instead of EHOSTUNREACH in case of unreachable route.
> In the inet address family, all three route types generated ICMP message
> net unreachable, and the local senders got ENETUNREACH error.
> 
> In both address families all three route types now behave consistently
> with documentation.
> 
> Signed-off-by: Nikola Forró <nforro@redhat.com>
> ---
>  include/net/ip_fib.h | 21 ++++++++++++++++-----
>  net/ipv4/route.c     |  6 ++++--
>  net/ipv6/route.c     |  4 +++-
>  3 files changed, 23 insertions(+), 8 deletions(-)
> 
> diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h
> index 5fa643b..cf025107 100644
> --- a/include/net/ip_fib.h
> +++ b/include/net/ip_fib.h
> @@ -233,8 +233,10 @@ static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
>  	rcu_read_lock();
>  
>  	tb = fib_get_table(net, RT_TABLE_MAIN);
> -	if (tb && !fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF))
> -		err = 0;
> +	if (tb)
> +		err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
> +		if (err == -EAGAIN)
> +			err = -ENETUNREACH;

Missing { } ?