From 8a3d03166f19329b46c6f9e900f93a89f446077b Mon Sep 17 00:00:00 2001 From: Andy Gospodarek Date: Tue, 23 Jun 2015 13:45:36 -0400 Subject: [PATCH 1/2] net: track link-status of ipv4 nexthops Add a fib flag called RTNH_F_LINKDOWN to any ipv4 nexthops that are reachable via an interface where carrier is off. No action is taken, but additional flags are passed to userspace to indicate carrier status. This also includes a cleanup to fib_disable_ip to more clearly indicate what event made the function call to replace the more cryptic force option previously used. v2: Split out kernel functionality into 2 patches, this patch simply sets and clears new nexthop flag RTNH_F_LINKDOWN. v3: Cleanups suggested by Alex as well as a bug noticed in fib_sync_down_dev and fib_sync_up when multipath was not enabled. v5: Whitespace and variable declaration fixups suggested by Dave. v6: Style fixups noticed by Dave; ran checkpatch to be sure I got them all. Signed-off-by: Andy Gospodarek Signed-off-by: Dinesh Dutt Acked-by: Scott Feldman Signed-off-by: David S. Miller --- include/net/ip_fib.h | 4 +-- include/uapi/linux/rtnetlink.h | 3 ++ net/ipv4/fib_frontend.c | 23 ++++++++----- net/ipv4/fib_semantics.c | 60 ++++++++++++++++++++++++++-------- 4 files changed, 67 insertions(+), 23 deletions(-) diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index 54271ed0ed45b..f73d27c5575ae 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -305,9 +305,9 @@ void fib_flush_external(struct net *net); /* Exported by fib_semantics.c */ int ip_fib_check_default(__be32 gw, struct net_device *dev); -int fib_sync_down_dev(struct net_device *dev, int force); +int fib_sync_down_dev(struct net_device *dev, unsigned long event); int fib_sync_down_addr(struct net *net, __be32 local); -int fib_sync_up(struct net_device *dev); +int fib_sync_up(struct net_device *dev, unsigned int nh_flags); void fib_select_multipath(struct fib_result *res); /* Exported by fib_trie.c */ diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h index 17fb02f488da8..fdd8f07f1d34b 100644 --- a/include/uapi/linux/rtnetlink.h +++ b/include/uapi/linux/rtnetlink.h @@ -338,6 +338,9 @@ struct rtnexthop { #define RTNH_F_PERVASIVE 2 /* Do recursive gateway lookup */ #define RTNH_F_ONLINK 4 /* Gateway is forced on link */ #define RTNH_F_OFFLOAD 8 /* offloaded route */ +#define RTNH_F_LINKDOWN 16 /* carrier-down on nexthop */ + +#define RTNH_COMPARE_MASK (RTNH_F_DEAD | RTNH_F_LINKDOWN) /* Macros to handle hexthops */ diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 872494e6e6eb7..534eb14850457 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -1063,9 +1063,9 @@ static void nl_fib_lookup_exit(struct net *net) net->ipv4.fibnl = NULL; } -static void fib_disable_ip(struct net_device *dev, int force) +static void fib_disable_ip(struct net_device *dev, unsigned long event) { - if (fib_sync_down_dev(dev, force)) + if (fib_sync_down_dev(dev, event)) fib_flush(dev_net(dev)); rt_cache_flush(dev_net(dev)); arp_ifdown(dev); @@ -1081,7 +1081,7 @@ static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, case NETDEV_UP: fib_add_ifaddr(ifa); #ifdef CONFIG_IP_ROUTE_MULTIPATH - fib_sync_up(dev); + fib_sync_up(dev, RTNH_F_DEAD); #endif atomic_inc(&net->ipv4.dev_addr_genid); rt_cache_flush(dev_net(dev)); @@ -1093,7 +1093,7 @@ static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, /* Last address was deleted from this interface. * Disable IP. */ - fib_disable_ip(dev, 1); + fib_disable_ip(dev, event); } else { rt_cache_flush(dev_net(dev)); } @@ -1107,9 +1107,10 @@ static int fib_netdev_event(struct notifier_block *this, unsigned long event, vo struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct in_device *in_dev; struct net *net = dev_net(dev); + unsigned int flags; if (event == NETDEV_UNREGISTER) { - fib_disable_ip(dev, 2); + fib_disable_ip(dev, event); rt_flush_dev(dev); return NOTIFY_DONE; } @@ -1124,16 +1125,22 @@ static int fib_netdev_event(struct notifier_block *this, unsigned long event, vo fib_add_ifaddr(ifa); } endfor_ifa(in_dev); #ifdef CONFIG_IP_ROUTE_MULTIPATH - fib_sync_up(dev); + fib_sync_up(dev, RTNH_F_DEAD); #endif atomic_inc(&net->ipv4.dev_addr_genid); rt_cache_flush(net); break; case NETDEV_DOWN: - fib_disable_ip(dev, 0); + fib_disable_ip(dev, event); break; - case NETDEV_CHANGEMTU: case NETDEV_CHANGE: + flags = dev_get_flags(dev); + if (flags & (IFF_RUNNING | IFF_LOWER_UP)) + fib_sync_up(dev, RTNH_F_LINKDOWN); + else + fib_sync_down_dev(dev, event); + /* fall through */ + case NETDEV_CHANGEMTU: rt_cache_flush(net); break; } diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 28ec3c1823bf3..b1b305b1e3405 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -266,7 +266,7 @@ static inline int nh_comp(const struct fib_info *fi, const struct fib_info *ofi) #ifdef CONFIG_IP_ROUTE_CLASSID nh->nh_tclassid != onh->nh_tclassid || #endif - ((nh->nh_flags ^ onh->nh_flags) & ~RTNH_F_DEAD)) + ((nh->nh_flags ^ onh->nh_flags) & ~RTNH_COMPARE_MASK)) return -1; onh++; } endfor_nexthops(fi); @@ -318,7 +318,7 @@ static struct fib_info *fib_find_info(const struct fib_info *nfi) nfi->fib_type == fi->fib_type && memcmp(nfi->fib_metrics, fi->fib_metrics, sizeof(u32) * RTAX_MAX) == 0 && - ((nfi->fib_flags ^ fi->fib_flags) & ~RTNH_F_DEAD) == 0 && + !((nfi->fib_flags ^ fi->fib_flags) & ~RTNH_COMPARE_MASK) && (nfi->fib_nhs == 0 || nh_comp(fi, nfi) == 0)) return fi; } @@ -604,6 +604,8 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi, return -ENODEV; if (!(dev->flags & IFF_UP)) return -ENETDOWN; + if (!netif_carrier_ok(dev)) + nh->nh_flags |= RTNH_F_LINKDOWN; nh->nh_dev = dev; dev_hold(dev); nh->nh_scope = RT_SCOPE_LINK; @@ -636,6 +638,8 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi, if (!dev) goto out; dev_hold(dev); + if (!netif_carrier_ok(dev)) + nh->nh_flags |= RTNH_F_LINKDOWN; err = (dev->flags & IFF_UP) ? 0 : -ENETDOWN; } else { struct in_device *in_dev; @@ -654,6 +658,8 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi, nh->nh_dev = in_dev->dev; dev_hold(nh->nh_dev); nh->nh_scope = RT_SCOPE_HOST; + if (!netif_carrier_ok(nh->nh_dev)) + nh->nh_flags |= RTNH_F_LINKDOWN; err = 0; } out: @@ -920,11 +926,17 @@ struct fib_info *fib_create_info(struct fib_config *cfg) if (!nh->nh_dev) goto failure; } else { + int linkdown = 0; + change_nexthops(fi) { err = fib_check_nh(cfg, fi, nexthop_nh); if (err != 0) goto failure; + if (nexthop_nh->nh_flags & RTNH_F_LINKDOWN) + linkdown++; } endfor_nexthops(fi) + if (linkdown == fi->fib_nhs) + fi->fib_flags |= RTNH_F_LINKDOWN; } if (fi->fib_prefsrc) { @@ -1103,7 +1115,7 @@ int fib_sync_down_addr(struct net *net, __be32 local) return ret; } -int fib_sync_down_dev(struct net_device *dev, int force) +int fib_sync_down_dev(struct net_device *dev, unsigned long event) { int ret = 0; int scope = RT_SCOPE_NOWHERE; @@ -1112,7 +1124,8 @@ int fib_sync_down_dev(struct net_device *dev, int force) struct hlist_head *head = &fib_info_devhash[hash]; struct fib_nh *nh; - if (force) + if (event == NETDEV_UNREGISTER || + event == NETDEV_DOWN) scope = -1; hlist_for_each_entry(nh, head, nh_hash) { @@ -1129,7 +1142,15 @@ int fib_sync_down_dev(struct net_device *dev, int force) dead++; else if (nexthop_nh->nh_dev == dev && nexthop_nh->nh_scope != scope) { - nexthop_nh->nh_flags |= RTNH_F_DEAD; + switch (event) { + case NETDEV_DOWN: + case NETDEV_UNREGISTER: + nexthop_nh->nh_flags |= RTNH_F_DEAD; + /* fall through */ + case NETDEV_CHANGE: + nexthop_nh->nh_flags |= RTNH_F_LINKDOWN; + break; + } #ifdef CONFIG_IP_ROUTE_MULTIPATH spin_lock_bh(&fib_multipath_lock); fi->fib_power -= nexthop_nh->nh_power; @@ -1139,14 +1160,23 @@ int fib_sync_down_dev(struct net_device *dev, int force) dead++; } #ifdef CONFIG_IP_ROUTE_MULTIPATH - if (force > 1 && nexthop_nh->nh_dev == dev) { + if (event == NETDEV_UNREGISTER && + nexthop_nh->nh_dev == dev) { dead = fi->fib_nhs; break; } #endif } endfor_nexthops(fi) if (dead == fi->fib_nhs) { - fi->fib_flags |= RTNH_F_DEAD; + switch (event) { + case NETDEV_DOWN: + case NETDEV_UNREGISTER: + fi->fib_flags |= RTNH_F_DEAD; + /* fall through */ + case NETDEV_CHANGE: + fi->fib_flags |= RTNH_F_LINKDOWN; + break; + } ret++; } } @@ -1210,13 +1240,11 @@ void fib_select_default(struct fib_result *res) return; } -#ifdef CONFIG_IP_ROUTE_MULTIPATH - /* * Dead device goes up. We wake up dead nexthops. * It takes sense only on multipath routes. */ -int fib_sync_up(struct net_device *dev) +int fib_sync_up(struct net_device *dev, unsigned int nh_flags) { struct fib_info *prev_fi; unsigned int hash; @@ -1243,7 +1271,7 @@ int fib_sync_up(struct net_device *dev) prev_fi = fi; alive = 0; change_nexthops(fi) { - if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) { + if (!(nexthop_nh->nh_flags & nh_flags)) { alive++; continue; } @@ -1254,14 +1282,18 @@ int fib_sync_up(struct net_device *dev) !__in_dev_get_rtnl(dev)) continue; alive++; +#ifdef CONFIG_IP_ROUTE_MULTIPATH spin_lock_bh(&fib_multipath_lock); nexthop_nh->nh_power = 0; - nexthop_nh->nh_flags &= ~RTNH_F_DEAD; + nexthop_nh->nh_flags &= ~nh_flags; spin_unlock_bh(&fib_multipath_lock); +#else + nexthop_nh->nh_flags &= ~nh_flags; +#endif } endfor_nexthops(fi) if (alive > 0) { - fi->fib_flags &= ~RTNH_F_DEAD; + fi->fib_flags &= ~nh_flags; ret++; } } @@ -1269,6 +1301,8 @@ int fib_sync_up(struct net_device *dev) return ret; } +#ifdef CONFIG_IP_ROUTE_MULTIPATH + /* * The algorithm is suboptimal, but it provides really * fair weighted route distribution. From 0eeb075fad736fb92620af995c47c204bbb5e829 Mon Sep 17 00:00:00 2001 From: Andy Gospodarek Date: Tue, 23 Jun 2015 13:45:37 -0400 Subject: [PATCH 2/2] net: ipv4 sysctl option to ignore routes when nexthop link is down This feature is only enabled with the new per-interface or ipv4 global sysctls called 'ignore_routes_with_linkdown'. net.ipv4.conf.all.ignore_routes_with_linkdown = 0 net.ipv4.conf.default.ignore_routes_with_linkdown = 0 net.ipv4.conf.lo.ignore_routes_with_linkdown = 0 ... When the above sysctls are set, will report to userspace that a route is dead and will no longer resolve to this nexthop when performing a fib lookup. This will signal to userspace that the route will not be selected. The signalling of a RTNH_F_DEAD is only passed to userspace if the sysctl is enabled and link is down. This was done as without it the netlink listeners would have no idea whether or not a nexthop would be selected. The kernel only sets RTNH_F_DEAD internally if the interface has IFF_UP cleared. With the new sysctl set, the following behavior can be observed (interface p8p1 is link-down): default via 10.0.5.2 dev p9p1 10.0.5.0/24 dev p9p1 proto kernel scope link src 10.0.5.15 70.0.0.0/24 dev p7p1 proto kernel scope link src 70.0.0.1 80.0.0.0/24 dev p8p1 proto kernel scope link src 80.0.0.1 dead linkdown 90.0.0.0/24 via 80.0.0.2 dev p8p1 metric 1 dead linkdown 90.0.0.0/24 via 70.0.0.2 dev p7p1 metric 2 90.0.0.1 via 70.0.0.2 dev p7p1 src 70.0.0.1 cache local 80.0.0.1 dev lo src 80.0.0.1 cache 80.0.0.2 via 10.0.5.2 dev p9p1 src 10.0.5.15 cache While the route does remain in the table (so it can be modified if needed rather than being wiped away as it would be if IFF_UP was cleared), the proper next-hop is chosen automatically when the link is down. Now interface p8p1 is linked-up: default via 10.0.5.2 dev p9p1 10.0.5.0/24 dev p9p1 proto kernel scope link src 10.0.5.15 70.0.0.0/24 dev p7p1 proto kernel scope link src 70.0.0.1 80.0.0.0/24 dev p8p1 proto kernel scope link src 80.0.0.1 90.0.0.0/24 via 80.0.0.2 dev p8p1 metric 1 90.0.0.0/24 via 70.0.0.2 dev p7p1 metric 2 192.168.56.0/24 dev p2p1 proto kernel scope link src 192.168.56.2 90.0.0.1 via 80.0.0.2 dev p8p1 src 80.0.0.1 cache local 80.0.0.1 dev lo src 80.0.0.1 cache 80.0.0.2 dev p8p1 src 80.0.0.1 cache and the output changes to what one would expect. If the sysctl is not set, the following output would be expected when p8p1 is down: default via 10.0.5.2 dev p9p1 10.0.5.0/24 dev p9p1 proto kernel scope link src 10.0.5.15 70.0.0.0/24 dev p7p1 proto kernel scope link src 70.0.0.1 80.0.0.0/24 dev p8p1 proto kernel scope link src 80.0.0.1 linkdown 90.0.0.0/24 via 80.0.0.2 dev p8p1 metric 1 linkdown 90.0.0.0/24 via 70.0.0.2 dev p7p1 metric 2 Since the dead flag does not appear, there should be no expectation that the kernel would skip using this route due to link being down. v2: Split kernel changes into 2 patches, this actually makes a behavioral change if the sysctl is set. Also took suggestion from Alex to simplify code by only checking sysctl during fib lookup and suggestion from Scott to add a per-interface sysctl. v3: Code clean-ups to make it more readable and efficient as well as a reverse path check fix. v4: Drop binary sysctl v5: Whitespace fixups from Dave v6: Style changes from Dave and checkpatch suggestions v7: One more checkpatch fixup Signed-off-by: Andy Gospodarek Signed-off-by: Dinesh Dutt Acked-by: Scott Feldman Signed-off-by: David S. Miller --- include/linux/inetdevice.h | 3 +++ include/net/fib_rules.h | 3 ++- include/net/ip_fib.h | 16 ++++++++------- include/uapi/linux/ip.h | 1 + net/ipv4/devinet.c | 2 ++ net/ipv4/fib_frontend.c | 6 +++--- net/ipv4/fib_rules.c | 5 +++-- net/ipv4/fib_semantics.c | 33 ++++++++++++++++++++++++++----- net/ipv4/fib_trie.c | 6 ++++++ net/ipv4/netfilter/ipt_rpfilter.c | 2 +- net/ipv4/route.c | 10 +++++----- 11 files changed, 63 insertions(+), 24 deletions(-) diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h index 0a21fbefdfbec..a4328cea376ab 100644 --- a/include/linux/inetdevice.h +++ b/include/linux/inetdevice.h @@ -120,6 +120,9 @@ static inline void ipv4_devconf_setall(struct in_device *in_dev) || (!IN_DEV_FORWARD(in_dev) && \ IN_DEV_ORCONF((in_dev), ACCEPT_REDIRECTS))) +#define IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) \ + IN_DEV_CONF_GET((in_dev), IGNORE_ROUTES_WITH_LINKDOWN) + #define IN_DEV_ARPFILTER(in_dev) IN_DEV_ORCONF((in_dev), ARPFILTER) #define IN_DEV_ARP_ACCEPT(in_dev) IN_DEV_ORCONF((in_dev), ARP_ACCEPT) #define IN_DEV_ARP_ANNOUNCE(in_dev) IN_DEV_MAXCONF((in_dev), ARP_ANNOUNCE) diff --git a/include/net/fib_rules.h b/include/net/fib_rules.h index 6d67383a5114b..903a55efbffe5 100644 --- a/include/net/fib_rules.h +++ b/include/net/fib_rules.h @@ -36,7 +36,8 @@ struct fib_lookup_arg { void *result; struct fib_rule *rule; int flags; -#define FIB_LOOKUP_NOREF 1 +#define FIB_LOOKUP_NOREF 1 +#define FIB_LOOKUP_IGNORE_LINKSTATE 2 }; struct fib_rules_ops { diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index f73d27c5575ae..49c142bdf01e6 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -226,7 +226,7 @@ static inline struct fib_table *fib_new_table(struct net *net, u32 id) } static inline int fib_lookup(struct net *net, const struct flowi4 *flp, - struct fib_result *res) + struct fib_result *res, unsigned int flags) { struct fib_table *tb; int err = -ENETUNREACH; @@ -234,7 +234,7 @@ static inline int fib_lookup(struct net *net, const struct flowi4 *flp, rcu_read_lock(); tb = fib_get_table(net, RT_TABLE_MAIN); - if (tb && !fib_table_lookup(tb, flp, res, FIB_LOOKUP_NOREF)) + if (tb && !fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF)) err = 0; rcu_read_unlock(); @@ -249,16 +249,18 @@ void __net_exit fib4_rules_exit(struct net *net); struct fib_table *fib_new_table(struct net *net, u32 id); struct fib_table *fib_get_table(struct net *net, u32 id); -int __fib_lookup(struct net *net, struct flowi4 *flp, struct fib_result *res); +int __fib_lookup(struct net *net, struct flowi4 *flp, + struct fib_result *res, unsigned int flags); static inline int fib_lookup(struct net *net, struct flowi4 *flp, - struct fib_result *res) + struct fib_result *res, unsigned int flags) { struct fib_table *tb; int err; + flags |= FIB_LOOKUP_NOREF; if (net->ipv4.fib_has_custom_rules) - return __fib_lookup(net, flp, res); + return __fib_lookup(net, flp, res, flags); rcu_read_lock(); @@ -266,11 +268,11 @@ static inline int fib_lookup(struct net *net, struct flowi4 *flp, for (err = 0; !err; err = -ENETUNREACH) { tb = rcu_dereference_rtnl(net->ipv4.fib_main); - if (tb && !fib_table_lookup(tb, flp, res, FIB_LOOKUP_NOREF)) + if (tb && !fib_table_lookup(tb, flp, res, flags)) break; tb = rcu_dereference_rtnl(net->ipv4.fib_default); - if (tb && !fib_table_lookup(tb, flp, res, FIB_LOOKUP_NOREF)) + if (tb && !fib_table_lookup(tb, flp, res, flags)) break; } diff --git a/include/uapi/linux/ip.h b/include/uapi/linux/ip.h index 411959405ab6e..08f894d2ddbd9 100644 --- a/include/uapi/linux/ip.h +++ b/include/uapi/linux/ip.h @@ -164,6 +164,7 @@ enum IPV4_DEVCONF_ROUTE_LOCALNET, IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL, IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL, + IPV4_DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN, __IPV4_DEVCONF_MAX }; diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 419d23c53ec75..7498716e8f541 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -2169,6 +2169,8 @@ static struct devinet_sysctl_table { "igmpv2_unsolicited_report_interval"), DEVINET_SYSCTL_RW_ENTRY(IGMPV3_UNSOLICITED_REPORT_INTERVAL, "igmpv3_unsolicited_report_interval"), + DEVINET_SYSCTL_RW_ENTRY(IGNORE_ROUTES_WITH_LINKDOWN, + "ignore_routes_with_linkdown"), DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"), DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"), diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 534eb14850457..6bbc54940eb4e 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -280,7 +280,7 @@ __be32 fib_compute_spec_dst(struct sk_buff *skb) fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos); fl4.flowi4_scope = scope; fl4.flowi4_mark = IN_DEV_SRC_VMARK(in_dev) ? skb->mark : 0; - if (!fib_lookup(net, &fl4, &res)) + if (!fib_lookup(net, &fl4, &res, 0)) return FIB_RES_PREFSRC(net, res); } else { scope = RT_SCOPE_LINK; @@ -319,7 +319,7 @@ static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, fl4.flowi4_mark = IN_DEV_SRC_VMARK(idev) ? skb->mark : 0; net = dev_net(dev); - if (fib_lookup(net, &fl4, &res)) + if (fib_lookup(net, &fl4, &res, 0)) goto last_resort; if (res.type != RTN_UNICAST && (res.type != RTN_LOCAL || !IN_DEV_ACCEPT_LOCAL(idev))) @@ -354,7 +354,7 @@ static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, fl4.flowi4_oif = dev->ifindex; ret = 0; - if (fib_lookup(net, &fl4, &res) == 0) { + if (fib_lookup(net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE) == 0) { if (res.type == RTN_UNICAST) ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST; } diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c index 56151982f74ef..18123d50f5761 100644 --- a/net/ipv4/fib_rules.c +++ b/net/ipv4/fib_rules.c @@ -47,11 +47,12 @@ struct fib4_rule { #endif }; -int __fib_lookup(struct net *net, struct flowi4 *flp, struct fib_result *res) +int __fib_lookup(struct net *net, struct flowi4 *flp, + struct fib_result *res, unsigned int flags) { struct fib_lookup_arg arg = { .result = res, - .flags = FIB_LOOKUP_NOREF, + .flags = flags, }; int err; diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index b1b305b1e3405..3bfccd83551ce 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -623,7 +623,8 @@ 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); + err = fib_lookup(net, &fl4, &res, + FIB_LOOKUP_IGNORE_LINKSTATE); if (err) { rcu_read_unlock(); return err; @@ -1035,12 +1036,20 @@ int fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event, nla_put_in_addr(skb, RTA_PREFSRC, fi->fib_prefsrc)) goto nla_put_failure; if (fi->fib_nhs == 1) { + struct in_device *in_dev; + if (fi->fib_nh->nh_gw && nla_put_in_addr(skb, RTA_GATEWAY, fi->fib_nh->nh_gw)) goto nla_put_failure; if (fi->fib_nh->nh_oif && nla_put_u32(skb, RTA_OIF, fi->fib_nh->nh_oif)) goto nla_put_failure; + if (fi->fib_nh->nh_flags & RTNH_F_LINKDOWN) { + in_dev = __in_dev_get_rcu(fi->fib_nh->nh_dev); + if (in_dev && + IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev)) + rtm->rtm_flags |= RTNH_F_DEAD; + } #ifdef CONFIG_IP_ROUTE_CLASSID if (fi->fib_nh[0].nh_tclassid && nla_put_u32(skb, RTA_FLOW, fi->fib_nh[0].nh_tclassid)) @@ -1057,11 +1066,19 @@ int fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event, goto nla_put_failure; for_nexthops(fi) { + struct in_device *in_dev; + rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh)); if (!rtnh) goto nla_put_failure; rtnh->rtnh_flags = nh->nh_flags & 0xFF; + if (nh->nh_flags & RTNH_F_LINKDOWN) { + in_dev = __in_dev_get_rcu(nh->nh_dev); + if (in_dev && + IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev)) + rtnh->rtnh_flags |= RTNH_F_DEAD; + } rtnh->rtnh_hops = nh->nh_weight - 1; rtnh->rtnh_ifindex = nh->nh_oif; @@ -1310,16 +1327,22 @@ int fib_sync_up(struct net_device *dev, unsigned int nh_flags) void fib_select_multipath(struct fib_result *res) { struct fib_info *fi = res->fi; + struct in_device *in_dev; int w; spin_lock_bh(&fib_multipath_lock); if (fi->fib_power <= 0) { int power = 0; change_nexthops(fi) { - if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) { - power += nexthop_nh->nh_weight; - nexthop_nh->nh_power = nexthop_nh->nh_weight; - } + in_dev = __in_dev_get_rcu(nexthop_nh->nh_dev); + if (nexthop_nh->nh_flags & RTNH_F_DEAD) + continue; + if (in_dev && + IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) && + nexthop_nh->nh_flags & RTNH_F_LINKDOWN) + continue; + power += nexthop_nh->nh_weight; + nexthop_nh->nh_power = nexthop_nh->nh_weight; } endfor_nexthops(fi); fi->fib_power = power; if (power <= 0) { diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index 6c666a9f1bd52..15d32612e3c6f 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -1412,9 +1412,15 @@ int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp, continue; for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) { const struct fib_nh *nh = &fi->fib_nh[nhsel]; + struct in_device *in_dev = __in_dev_get_rcu(nh->nh_dev); if (nh->nh_flags & RTNH_F_DEAD) continue; + if (in_dev && + IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) && + nh->nh_flags & RTNH_F_LINKDOWN && + !(fib_flags & FIB_LOOKUP_IGNORE_LINKSTATE)) + continue; if (flp->flowi4_oif && flp->flowi4_oif != nh->nh_oif) continue; diff --git a/net/ipv4/netfilter/ipt_rpfilter.c b/net/ipv4/netfilter/ipt_rpfilter.c index 4bfaedf9b34e5..8618fd150c965 100644 --- a/net/ipv4/netfilter/ipt_rpfilter.c +++ b/net/ipv4/netfilter/ipt_rpfilter.c @@ -40,7 +40,7 @@ static bool rpfilter_lookup_reverse(struct flowi4 *fl4, struct net *net = dev_net(dev); int ret __maybe_unused; - if (fib_lookup(net, fl4, &res)) + if (fib_lookup(net, fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE)) return false; if (res.type != RTN_UNICAST) { diff --git a/net/ipv4/route.c b/net/ipv4/route.c index f6055984c3070..d0362a2de3d38 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -747,7 +747,7 @@ static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flow if (!(n->nud_state & NUD_VALID)) { neigh_event_send(n, NULL); } else { - if (fib_lookup(net, fl4, &res) == 0) { + if (fib_lookup(net, fl4, &res, 0) == 0) { struct fib_nh *nh = &FIB_RES_NH(res); update_or_create_fnhe(nh, fl4->daddr, new_gw, @@ -975,7 +975,7 @@ static void __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu) return; rcu_read_lock(); - if (fib_lookup(dev_net(dst->dev), fl4, &res) == 0) { + if (fib_lookup(dev_net(dst->dev), fl4, &res, 0) == 0) { struct fib_nh *nh = &FIB_RES_NH(res); update_or_create_fnhe(nh, fl4->daddr, 0, mtu, @@ -1186,7 +1186,7 @@ void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt) fl4.flowi4_mark = skb->mark; rcu_read_lock(); - if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res) == 0) + if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res, 0) == 0) src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res); else src = inet_select_addr(rt->dst.dev, @@ -1716,7 +1716,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, fl4.flowi4_scope = RT_SCOPE_UNIVERSE; fl4.daddr = daddr; fl4.saddr = saddr; - err = fib_lookup(net, &fl4, &res); + err = fib_lookup(net, &fl4, &res, 0); if (err != 0) { if (!IN_DEV_FORWARD(in_dev)) err = -EHOSTUNREACH; @@ -2123,7 +2123,7 @@ struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4) goto make_route; } - if (fib_lookup(net, fl4, &res)) { + if (fib_lookup(net, fl4, &res, 0)) { res.fi = NULL; res.table = NULL; if (fl4->flowi4_oif) {