From e98e4b8899a696e13bcfcc8fa25b3546c1f4c244 Mon Sep 17 00:00:00 2001 From: Anuradha Karuppiah Date: Thu, 11 Oct 2018 08:48:42 -0700 Subject: [PATCH] zebra: send a local-mac del to bgpd on mac mod to remote When events cross paths between bgp and zebra bgpd could end up with a dangling local MAC entry. Consider the following sequence of events on rack-1 - 1. MAC1 has MM sequence number 1 and points to rack-3 2. Now a packet is rxed locally on rack-1 and rack-2 (simultaneously) with source-mac=MAC1. 3. This would cause rack-1 and rack-2 to set the MM seq to 2 and simultaneously report the MAC as local. 4. Now let's say on rack-1 zebra's MACIP_ADD is in bgpd's queue. bgpd accepts rack-3's update and sends a remote MACIP add to zebra with MM=2. 5. zebra updates the MAC entry from local=>remote. 6. bgpd now processes zebra's "stale local" making it the best path. However zebra no longer has a local MAC entry. At this point bgpd and zebra are effectively out of sync i.e. bgpd has a local-MAC which is not present in the kernel or in zebra. To handle this window zebra should send a local MAC delete to bgpd on modifying its cache to remote. Ticket: CM-22687 Reviewed By: CCR-7935 Signed-off-by: Anuradha Karuppiah --- zebra/zebra_vxlan.c | 28 ++++++++++++---------------- 1 file changed, 12 insertions(+), 16 deletions(-) diff --git a/zebra/zebra_vxlan.c b/zebra/zebra_vxlan.c index 58cf6eb30f..9ecf834333 100644 --- a/zebra/zebra_vxlan.c +++ b/zebra/zebra_vxlan.c @@ -148,8 +148,7 @@ static void zvni_mac_del_all(zebra_vni_t *zvni, int uninstall, int upd_client, static zebra_mac_t *zvni_mac_lookup(zebra_vni_t *zvni, struct ethaddr *macaddr); static int zvni_mac_send_add_to_client(vni_t vni, struct ethaddr *macaddr, uint8_t flags, uint32_t seq); -static int zvni_mac_send_del_to_client(vni_t vni, struct ethaddr *macaddr, - uint8_t flags); +static int zvni_mac_send_del_to_client(vni_t vni, struct ethaddr *macaddr); static zebra_vni_t *zvni_map_vlan(struct interface *ifp, struct interface *br_if, vlanid_t vid); static int zvni_mac_install(zebra_vni_t *zvni, zebra_mac_t *mac); @@ -2321,7 +2320,7 @@ static void zvni_mac_del_hash_entry(struct hash_backet *backet, void *arg) &wctx->r_vtep_ip))) { if (wctx->upd_client && (mac->flags & ZEBRA_MAC_LOCAL)) { zvni_mac_send_del_to_client(wctx->zvni->vni, - &mac->macaddr, mac->flags); + &mac->macaddr); } if (wctx->uninstall) @@ -2408,18 +2407,10 @@ static int zvni_mac_send_add_to_client(vni_t vni, struct ethaddr *macaddr, /* * Inform BGP about local MAC deletion. */ -static int zvni_mac_send_del_to_client(vni_t vni, struct ethaddr *macaddr, - uint8_t mac_flags) +static int zvni_mac_send_del_to_client(vni_t vni, struct ethaddr *macaddr) { - uint8_t flags = 0; - - if (CHECK_FLAG(mac_flags, ZEBRA_MAC_STICKY)) - SET_FLAG(flags, ZEBRA_MACIP_TYPE_STICKY); - if (CHECK_FLAG(mac_flags, ZEBRA_MAC_DEF_GW)) - SET_FLAG(flags, ZEBRA_MACIP_TYPE_GW); - - return zvni_macip_send_msg_to_client(vni, macaddr, NULL, flags, - 0, ZEBRA_MACIP_DEL); + return zvni_macip_send_msg_to_client(vni, macaddr, NULL, 0 /* flags */, + 0 /* seq */, ZEBRA_MACIP_DEL); } /* @@ -4218,6 +4209,10 @@ static void process_remote_macip_add(vni_t vni, } } + /* Remove local MAC from BGP. */ + if (CHECK_FLAG(mac->flags, ZEBRA_MAC_LOCAL)) + zvni_mac_send_del_to_client(zvni->vni, macaddr); + /* Set "auto" and "remote" forwarding info. */ UNSET_FLAG(mac->flags, ZEBRA_MAC_LOCAL); memset(&mac->fwd_info, 0, sizeof(mac->fwd_info)); @@ -4238,6 +4233,7 @@ static void process_remote_macip_add(vni_t vni, /* Install the entry. */ zvni_mac_install(zvni, mac); + } /* Update seq number. */ @@ -5631,7 +5627,7 @@ int zebra_vxlan_check_del_local_mac(struct interface *ifp, ifp->ifindex, vni); /* Remove MAC from BGP. */ - zvni_mac_send_del_to_client(zvni->vni, macaddr, mac->flags); + zvni_mac_send_del_to_client(zvni->vni, macaddr); /* * If there are no neigh associated with the mac delete the mac @@ -5742,7 +5738,7 @@ int zebra_vxlan_local_mac_del(struct interface *ifp, struct interface *br_if, zvni_process_neigh_on_local_mac_del(zvni, mac); /* Remove MAC from BGP. */ - zvni_mac_send_del_to_client(zvni->vni, macaddr, mac->flags); + zvni_mac_send_del_to_client(zvni->vni, macaddr); /* * If there are no neigh associated with the mac delete the mac -- 2.39.5