diff options
Diffstat (limited to 'net/ipv4/fib_semantics.c')
| -rw-r--r-- | net/ipv4/fib_semantics.c | 40 |
1 files changed, 35 insertions, 5 deletions
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 2b68418c7..539fa264e 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -479,6 +479,9 @@ static int fib_get_nhs(struct fib_info *fi, struct rtnexthop *rtnh, if (!rtnh_ok(rtnh, remaining)) return -EINVAL; + if (rtnh->rtnh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)) + return -EINVAL; + nexthop_nh->nh_flags = (cfg->fc_flags & ~0xFF) | rtnh->rtnh_flags; nexthop_nh->nh_oif = rtnh->rtnh_ifindex; @@ -1003,6 +1006,9 @@ struct fib_info *fib_create_info(struct fib_config *cfg) if (fib_props[cfg->fc_type].scope > cfg->fc_scope) goto err_inval; + if (cfg->fc_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)) + goto err_inval; + #ifdef CONFIG_IP_ROUTE_MULTIPATH if (cfg->fc_mp) { nhs = fib_count_nexthops(cfg->fc_mp, cfg->fc_mp_len); @@ -1561,21 +1567,45 @@ int fib_sync_up(struct net_device *dev, unsigned int nh_flags) } #ifdef CONFIG_IP_ROUTE_MULTIPATH +static bool fib_good_nh(const struct fib_nh *nh) +{ + int state = NUD_REACHABLE; + + if (nh->nh_scope == RT_SCOPE_LINK) { + struct neighbour *n; + + rcu_read_lock_bh(); + + n = __ipv4_neigh_lookup_noref(nh->nh_dev, nh->nh_gw); + if (n) + state = n->nud_state; + + rcu_read_unlock_bh(); + } + + return !!(state & NUD_VALID); +} void fib_select_multipath(struct fib_result *res, int hash) { struct fib_info *fi = res->fi; + struct net *net = fi->fib_net; + bool first = false; for_nexthops(fi) { if (hash > atomic_read(&nh->nh_upper_bound)) continue; - res->nh_sel = nhsel; - return; + if (!net->ipv4.sysctl_fib_multipath_use_neigh || + fib_good_nh(nh)) { + res->nh_sel = nhsel; + return; + } + if (!first) { + res->nh_sel = nhsel; + first = true; + } } endfor_nexthops(fi); - - /* Race condition: route has just become dead. */ - res->nh_sel = 0; } #endif |