| Message ID | 20240202082200.227031-2-thinker.li@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | Remove expired routes with a separated list of routes. | expand |
On Fri, Feb 02, 2024 at 12:21:56AM -0800, thinker.li@gmail.com wrote: > From: Kui-Feng Lee <thinker.li@gmail.com> > > 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 <thinker.li@gmail.com> > --- > 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 > Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
On 2/2/24 1:21 AM, thinker.li@gmail.com wrote: > From: Kui-Feng Lee <thinker.li@gmail.com> > > 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 <thinker.li@gmail.com> > --- > include/net/ip6_route.h | 3 ++- > net/ipv6/ndisc.c | 3 ++- > net/ipv6/route.c | 4 +++- > 3 files changed, 7 insertions(+), 3 deletions(-) > Suggested-by: David Ahern <dsahern@kernel.org> Reviewed-by: David Ahern <dsahern@kernel.org>
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;