ofproto-dpif: Fix uninitialized struct member in xlate_actions().

Commit 7257b535ab "Implement new fragment handling policy." moved around
a bunch of initialization code in xlate_actions() so that the assignment
to ctx->flow.tp_src and .tp_dst would not have to also assign to
ctx->base_flow.tp_src and .tp_dst.  However, this meant that the early-exit
"return" in the new switch statement exited without initializing a lot of
the context.  In particular 'may_set_up_flow' didn't get initialized, so
something the early-exit would produce a flow that couldn't be installed,
which wasn't the intent.

It seems that this optimization was a bad tradeoff, so this commit puts
all of the initialization up front and just assigns to both copies of the
tp_src and tp_dst members.

Fixes a nondeterministic "make check" failure in the VLAN handling test.

diff --git a/ofproto/ofproto-dpif.c b/ofproto/ofproto-dpif.c
index de600f0..b53452d 100644 (file)
--- a/ofproto/ofproto-dpif.c
+++ b/ofproto/ofproto-dpif.c
@@ -4289,13 +4289,24 @@ xlate_actions(struct action_xlate_ctx *ctx,
 
     ctx->odp_actions = ofpbuf_new(512);
     ofpbuf_reserve(ctx->odp_actions, NL_A_U32_SIZE);
+    ctx->tags = 0;
+    ctx->may_set_up_flow = true;
+    ctx->has_learn = false;
+    ctx->has_normal = false;
+    ctx->nf_output_iface = NF_OUT_DROP;
+    ctx->recurse = 0;
+    ctx->priority = 0;
+    ctx->base_priority = 0;
+    ctx->base_flow = ctx->flow;
+    ctx->base_flow.tun_id = 0;
+    ctx->table_id = 0;
 
     if (ctx->flow.tos_frag & FLOW_FRAG_ANY) {
         switch (ctx->ofproto->up.frag_handling) {
         case OFPC_FRAG_NORMAL:
             /* We must pretend that transport ports are unavailable. */
-            ctx->flow.tp_src = htons(0);
-            ctx->flow.tp_dst = htons(0);
+            ctx->flow.tp_src = ctx->base_flow.tp_src = htons(0);
+            ctx->flow.tp_dst = ctx->base_flow.tp_dst = htons(0);
             break;
 
         case OFPC_FRAG_DROP:
@@ -4310,18 +4321,6 @@ xlate_actions(struct action_xlate_ctx *ctx,
         }
     }
 
-    ctx->tags = 0;
-    ctx->may_set_up_flow = true;
-    ctx->has_learn = false;
-    ctx->has_normal = false;
-    ctx->nf_output_iface = NF_OUT_DROP;
-    ctx->recurse = 0;
-    ctx->priority = 0;
-    ctx->base_priority = 0;
-    ctx->base_flow = ctx->flow;
-    ctx->base_flow.tun_id = 0;
-    ctx->table_id = 0;
-
     if (process_special(ctx->ofproto, &ctx->flow, ctx->packet)) {
         ctx->may_set_up_flow = false;
         return ctx->odp_actions;