Properly build the nidmap

When operating in a managed environment where the
user subdivides the allocation (e.g., by providing
a hostfile that contains only some of the allocated
nodes), the nidmap was overrunning the allocated
array for daemon vpids. Properly index the vpid
entries to avoid the memory corruption problem.

Signed-off-by: Ralph Castain <[email protected]>
(cherry picked from commit cfda800)

src/util/nidmap.c

@@ -86,6 +86,9 @@ int prte_util_nidmap_create(pmix_pointer_array_t *pool, pmix_data_buffer_t *buff
         if (NULL == (nptr = (prte_node_t *) pmix_pointer_array_get_item(pool, n))) {
             continue;
         }
+        if (NULL == nptr->daemon) {
+            continue;
+        }
         /* add the hostname to the argv */
         PMIX_ARGV_APPEND_NOSIZE_COMPAT(&names, nptr->name);
         als = NULL;
@@ -101,11 +104,7 @@ int prte_util_nidmap_create(pmix_pointer_array_t *pool, pmix_data_buffer_t *buff
             PMIX_ARGV_APPEND_NOSIZE_COMPAT(&aliases, "PRTENONE");
         }
         /* store the vpid */
-        if (NULL == nptr->daemon) {
-            vpids[ndaemons] = PMIX_RANK_INVALID;
-        } else {
-            vpids[ndaemons] = nptr->daemon->name.rank;
-        }
+        vpids[ndaemons] = nptr->daemon->name.rank;
         ++ndaemons;
     }
 
@@ -398,22 +397,20 @@ int prte_util_decode_nidmap(pmix_data_buffer_t *buf)
         /* set the topology - always default to homogeneous
          * as that is the most common scenario */
         nd->topology = t;
-        /* see if it has a daemon on it */
-        if (PMIX_RANK_INVALID != vpid[n]) {
-            proc = (prte_proc_t *) pmix_pointer_array_get_item(daemons->procs, vpid[n]);
-            if (NULL == proc) {
-                proc = PMIX_NEW(prte_proc_t);
-                PMIX_LOAD_PROCID(&proc->name, PRTE_PROC_MY_NAME->nspace, vpid[n]);
-                proc->state = PRTE_PROC_STATE_RUNNING;
-                PRTE_FLAG_SET(proc, PRTE_PROC_FLAG_ALIVE);
-                daemons->num_procs++;
-                pmix_pointer_array_set_item(daemons->procs, proc->name.rank, proc);
-            }
-            PMIX_RETAIN(nd);
-            proc->node = nd;
-            PMIX_RETAIN(proc);
-            nd->daemon = proc;
+        /* record the daemon on it */
+        proc = (prte_proc_t *) pmix_pointer_array_get_item(daemons->procs, vpid[n]);
+        if (NULL == proc) {
+            proc = PMIX_NEW(prte_proc_t);
+            PMIX_LOAD_PROCID(&proc->name, PRTE_PROC_MY_NAME->nspace, vpid[n]);
+            proc->state = PRTE_PROC_STATE_RUNNING;
+            PRTE_FLAG_SET(proc, PRTE_PROC_FLAG_ALIVE);
+            daemons->num_procs++;
+            pmix_pointer_array_set_item(daemons->procs, proc->name.rank, proc);
         }
+        PMIX_RETAIN(nd);
+        proc->node = nd;
+        PMIX_RETAIN(proc);
+        nd->daemon = proc;
     }
 
     /* update num procs */