[PATCH net-next v3 1/5] net/ipv6: set expires in rt6_add_dflt_router().
From: <hidden>
Date: 2024-02-02 08:22:16
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
From: Kui-Feng Lee <redacted> Pass the duration of a lifetime (in seconds) to the function rt6_add_dflt_router() so that it can properly set the expiration time. The function ndisc_router_discovery() is the only one that calls rt6_add_dflt_router(), and it will later set the expiration time for the route created by rt6_add_dflt_router(). However, there is a gap of time between calling rt6_add_dflt_router() and setting the expiration time in ndisc_router_discovery(). During this period, there is a possibility that a new route may be removed from the routing table. By setting the correct expiration time in rt6_add_dflt_router(), we can prevent this from happening. The reason for setting RTF_EXPIRES in rt6_add_dflt_router() is to start the Garbage Collection (GC) timer, as it only activates when a route with RTF_EXPIRES is added to a table. Signed-off-by: Kui-Feng Lee <redacted> --- include/net/ip6_route.h | 3 ++- net/ipv6/ndisc.c | 3 ++- net/ipv6/route.c | 4 +++- 3 files changed, 7 insertions(+), 3 deletions(-)
diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h
index 28b065790261..52a51c69aa9d 100644
--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h@@ -170,7 +170,8 @@ struct fib6_info *rt6_get_dflt_router(struct net *net, struct fib6_info *rt6_add_dflt_router(struct net *net, const struct in6_addr *gwaddr, struct net_device *dev, unsigned int pref, - u32 defrtr_usr_metric); + u32 defrtr_usr_metric, + int lifetime); void rt6_purge_dflt_routers(struct net *net);
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index a19999b30bc0..a68462668158 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c@@ -1382,7 +1382,8 @@ static enum skb_drop_reason ndisc_router_discovery(struct sk_buff *skb) neigh_release(neigh); rt = rt6_add_dflt_router(net, &ipv6_hdr(skb)->saddr, - skb->dev, pref, defrtr_usr_metric); + skb->dev, pref, defrtr_usr_metric, + lifetime); if (!rt) { ND_PRINTK(0, err, "RA: %s failed to add default route\n",
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 63b4c6056582..98abba8f15cd 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c@@ -4355,7 +4355,8 @@ struct fib6_info *rt6_add_dflt_router(struct net *net, const struct in6_addr *gwaddr, struct net_device *dev, unsigned int pref, - u32 defrtr_usr_metric) + u32 defrtr_usr_metric, + int lifetime) { struct fib6_config cfg = { .fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
@@ -4368,6 +4369,7 @@ struct fib6_info *rt6_add_dflt_router(struct net *net, .fc_nlinfo.portid = 0, .fc_nlinfo.nlh = NULL, .fc_nlinfo.nl_net = net, + .fc_expires = jiffies_to_clock_t(lifetime * HZ), }; cfg.fc_gateway = *gwaddr;
--
2.34.1