ipv6: take care of disable_policy when restoring routes

When routes corresponding to addresses are restored by
fixup_permanent_addr(), the dst_nopolicy parameter was not set.
The typical use case is a user that configures an address on a down
interface and then put this interface up.

Let's take care of this flag in addrconf_f6i_alloc(), so that every callers
benefit ont it.

CC: stable@kernel.org
CC: David Forster <dforster@brocade.com>
Fixes: df789fe7 ("ipv6: Provide ipv6 version of "disable_policy" sysctl")
Reported-by: Siwar Zitouni <siwar.zitouni@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220623120015.32640-1-nicolas.dichtel@6wind.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

net/ipv6/addrconf.c

@@ -1109,10 +1109,6 @@ ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
 		goto out;
 	}
 
-	if (net->ipv6.devconf_all->disable_policy ||
-	    idev->cnf.disable_policy)
-		f6i->dst_nopolicy = true;
-
 	neigh_parms_data_state_setall(idev->nd_parms);
 
 	ifa->addr = *cfg->pfx;

net/ipv6/route.c

@@ -4569,8 +4569,15 @@ struct fib6_info *addrconf_f6i_alloc(struct net *net,
 	}
 
 	f6i = ip6_route_info_create(&cfg, gfp_flags, NULL);
-	if (!IS_ERR(f6i))
+	if (!IS_ERR(f6i)) {
 		f6i->dst_nocount = true;
+
+		if (!anycast &&
+		    (net->ipv6.devconf_all->disable_policy ||
+		     idev->cnf.disable_policy))
+			f6i->dst_nopolicy = true;
+	}
+
 	return f6i;
 }