net: Use passed in table for nexthop lookups

If a user passes in a table for new routes use that table for nexthop
lookups. Specifically, this solves the case where a connected route does
not exist in the main table, but only another table and then a subsequent
route is added with a next hop using the connected route. ie.,

$ ip route ls
default via 10.0.2.2 dev eth0
10.0.2.0/24 dev eth0  proto kernel  scope link  src 10.0.2.15
169.254.0.0/16 dev eth0  scope link  metric 1003
192.168.56.0/24 dev eth1  proto kernel  scope link  src 192.168.56.51

$ ip route ls table 10
1.1.1.0/24 dev eth2  scope link

Without this patch adding a nexthop route fails:

$ ip route add table 10 2.2.2.0/24 via 1.1.1.10
RTNETLINK answers: Network is unreachable

With this patch the route is added successfully.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David Ahern 2015-08-13 14:59:07 -06:00 committed by David S. Miller
parent 021dd3b8a1
commit 3bfd847203

View File

@ -691,6 +691,7 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi,
}
rcu_read_lock();
{
struct fib_table *tbl = NULL;
struct flowi4 fl4 = {
.daddr = nh->nh_gw,
.flowi4_scope = cfg->fc_scope + 1,
@ -701,8 +702,16 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi,
/* It is not necessary, but requires a bit of thinking */
if (fl4.flowi4_scope < RT_SCOPE_LINK)
fl4.flowi4_scope = RT_SCOPE_LINK;
err = fib_lookup(net, &fl4, &res,
FIB_LOOKUP_IGNORE_LINKSTATE);
if (cfg->fc_table)
tbl = fib_get_table(net, cfg->fc_table);
if (tbl)
err = fib_table_lookup(tbl, &fl4, &res,
FIB_LOOKUP_IGNORE_LINKSTATE);
else
err = fib_lookup(net, &fl4, &res,
FIB_LOOKUP_IGNORE_LINKSTATE);
if (err) {
rcu_read_unlock();
return err;