[ovs-dev] [PATCH v3 3/4] Native tunnel: Do not refresh the entry while revalidating.

Paolo Valerio pvalerio at redhat.com
Fri Nov 26 23:12:58 UTC 2021


This is a minor issue but visible e.g. when you try to flush the neigh
cache while the ARP flow is still present in the datapath, triggering
the revalidation of the datapath flows which subsequently
refreshes/adds the entry in the cache.

Signed-off-by: Paolo Valerio <pvalerio at redhat.com>
Acked-by: Flavio Leitner <fbl at sysclose.org>
---
v2:
- renamed update -> allow_update
---
 lib/tnl-neigh-cache.c        |   20 +++++++++++++-------
 lib/tnl-neigh-cache.h        |    2 +-
 ofproto/ofproto-dpif-xlate.c |    3 ++-
 3 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/lib/tnl-neigh-cache.c b/lib/tnl-neigh-cache.c
index 0b9098011..eb3bdbc8e 100644
--- a/lib/tnl-neigh-cache.c
+++ b/lib/tnl-neigh-cache.c
@@ -174,7 +174,7 @@ tnl_arp_set(const char name[IFNAMSIZ], ovs_be32 dst,
 
 static int
 tnl_arp_snoop(const struct flow *flow, struct flow_wildcards *wc,
-              const char name[IFNAMSIZ])
+              const char name[IFNAMSIZ], bool allow_update)
 {
     /* Snoop normal ARP replies and gratuitous ARP requests/replies only */
     if (!is_arp(flow)
@@ -184,13 +184,17 @@ tnl_arp_snoop(const struct flow *flow, struct flow_wildcards *wc,
         return EINVAL;
     }
 
-    tnl_arp_set(name, FLOW_WC_GET_AND_MASK_WC(flow, wc, nw_src), flow->arp_sha);
+    memset(&wc->masks.nw_src, 0xff, sizeof wc->masks.nw_src);
+
+    if (allow_update) {
+        tnl_arp_set(name, flow->nw_src, flow->arp_sha);
+    }
     return 0;
 }
 
 static int
 tnl_nd_snoop(const struct flow *flow, struct flow_wildcards *wc,
-             const char name[IFNAMSIZ])
+             const char name[IFNAMSIZ], bool allow_update)
 {
     if (!is_nd(flow, wc) || flow->tp_src != htons(ND_NEIGHBOR_ADVERT)) {
         return EINVAL;
@@ -209,20 +213,22 @@ tnl_nd_snoop(const struct flow *flow, struct flow_wildcards *wc,
     memset(&wc->masks.ipv6_dst, 0xff, sizeof wc->masks.ipv6_dst);
     memset(&wc->masks.nd_target, 0xff, sizeof wc->masks.nd_target);
 
-    tnl_neigh_set__(name, &flow->nd_target, flow->arp_tha);
+    if (allow_update) {
+        tnl_neigh_set__(name, &flow->nd_target, flow->arp_tha);
+    }
     return 0;
 }
 
 int
 tnl_neigh_snoop(const struct flow *flow, struct flow_wildcards *wc,
-                const char name[IFNAMSIZ])
+                const char name[IFNAMSIZ], bool allow_update)
 {
     int res;
-    res = tnl_arp_snoop(flow, wc, name);
+    res = tnl_arp_snoop(flow, wc, name, allow_update);
     if (res != EINVAL) {
         return res;
     }
-    return tnl_nd_snoop(flow, wc, name);
+    return tnl_nd_snoop(flow, wc, name, allow_update);
 }
 
 void
diff --git a/lib/tnl-neigh-cache.h b/lib/tnl-neigh-cache.h
index e4b42b059..59804ea3e 100644
--- a/lib/tnl-neigh-cache.h
+++ b/lib/tnl-neigh-cache.h
@@ -32,7 +32,7 @@
 #include "util.h"
 
 int tnl_neigh_snoop(const struct flow *flow, struct flow_wildcards *wc,
-                    const char dev_name[IFNAMSIZ]);
+                    const char dev_name[IFNAMSIZ], bool allow_update);
 int tnl_neigh_lookup(const char dev_name[IFNAMSIZ], const struct in6_addr *dst,
                      struct eth_addr *mac);
 void tnl_neigh_cache_init(void);
diff --git a/ofproto/ofproto-dpif-xlate.c b/ofproto/ofproto-dpif-xlate.c
index 9d336bc6a..9cf414ee8 100644
--- a/ofproto/ofproto-dpif-xlate.c
+++ b/ofproto/ofproto-dpif-xlate.c
@@ -4097,7 +4097,8 @@ terminate_native_tunnel(struct xlate_ctx *ctx, struct flow *flow,
             (flow->dl_type == htons(ETH_TYPE_ARP) ||
              flow->nw_proto == IPPROTO_ICMPV6) &&
              is_neighbor_reply_correct(ctx, flow)) {
-            tnl_neigh_snoop(flow, wc, ctx->xbridge->name);
+            tnl_neigh_snoop(flow, wc, ctx->xbridge->name,
+                            ctx->xin->allow_side_effects);
         }
     }
 



More information about the dev mailing list