osc: fixed issues identified by coverity

Fix CID 1324733: Null pointer dereferences  (FORWARD_NULL)
Fix CID 1324734: Null pointer dereferences  (FORWARD_NULL)
Fix CID 1324735: Null pointer dereferences  (FORWARD_NULL)
Fix CID 1324736: Null pointer dereferences  (FORWARD_NULL)
Fix CID 1324737: Null pointer dereferences  (FORWARD_NULL)
Fix CID 1324751: Memory - illegal accesses  (USE_AFTER_FREE)
Fix CID 1324750: (USE_AFTER_FREE)
Fix CID 1324749: Memory - corruptions  (USE_AFTER_FREE)
Fix CID 1324748: Memory - illegal accesses  (USE_AFTER_FREE)
Fix CID 1324747: (USE_AFTER_FREE)
Fix CID 1324746: Memory - corruptions  (USE_AFTER_FREE)

Add missing return on an error path.

Fix CID 1324745: Code maintainability issues  (UNUSED_VALUE)

Ignore return code from barrier. It was not being used anyway.

Fix CID 1324738: Null pointer dereferences  (FORWARD_NULL)
Fix CID 1324741: Null pointer dereferences  (REVERSE_INULL)

module->selected_btl can not be NULL in osc/rdma during normal
operation. Removed the unnecessary NULL check.

Fix CID 1324752: Memory - illegal accesses  (USE_AFTER_FREE)

Move ompi_osc_pt2pt_module_lock_remove to before the lock is freed.

Fix CID 1324744: Uninitialized variables  (UNINIT)
Fix CID 1324743: Uninitialized variables  (UNINIT)

This array is not used unitialized but there is no reason not to use
calloc here to silence the warning.

The following CID is a false positive: 1324742. I will mark it such in
coverity.

Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>

ompi/mca/osc/pt2pt/osc_pt2pt_active_target.c

@@ -79,13 +79,14 @@ static ompi_osc_pt2pt_peer_t **ompi_osc_pt2pt_get_peers (ompi_osc_pt2pt_module_t
     int *ranks1, *ranks2;
     int ret;
 
-    ranks1 = malloc (sizeof(int) * size);
-    ranks2 = malloc (sizeof(int) * size);
-    peers = malloc (sizeof (ompi_osc_pt2pt_peer_t *) * size);
+    ranks1 = calloc (size, sizeof(int));
+    ranks2 = calloc (size, sizeof(int));
+    peers = calloc (size, sizeof (ompi_osc_rdma_peer_t *));
     if (NULL == ranks1 || NULL == ranks2 || NULL == peers) {
         free (ranks1);
         free (ranks2);
         free (peers);
+        return NULL;
     }
 
     for (int i = 0 ; i < size ; ++i) {

ompi/mca/osc/pt2pt/osc_pt2pt_module.c

@@ -55,8 +55,8 @@ int ompi_osc_pt2pt_free(ompi_win_t *win)
 
         /* finish with a barrier */
         if (ompi_group_size(win->w_group) > 1) {
-            ret = module->comm->c_coll.coll_barrier(module->comm,
-                                                    module->comm->c_coll.coll_barrier_module);
+            (void) module->comm->c_coll.coll_barrier (module->comm,
+                                                      module->comm->c_coll.coll_barrier_module);
         }
 
         /* remove from component information */

ompi/mca/osc/pt2pt/osc_pt2pt_passive_target.c

@@ -408,6 +408,8 @@ static int ompi_osc_pt2pt_unlock_internal (int target, ompi_win_t *win)
     }
 
     OPAL_THREAD_LOCK(&module->lock);
+    ompi_osc_pt2pt_module_lock_remove (module, lock);
+
     if (-1 != lock->sync.lock.target) {
         ompi_osc_pt2pt_sync_return (lock);
     } else {
@@ -415,7 +417,6 @@ static int ompi_osc_pt2pt_unlock_internal (int target, ompi_win_t *win)
     }
 
     --module->passive_target_access_epoch;
-    ompi_osc_pt2pt_module_lock_remove (module, lock);
 
     OPAL_THREAD_UNLOCK(&module->lock);
 

ompi/mca/osc/rdma/osc_rdma_active_target.c

@@ -103,13 +103,14 @@ static ompi_osc_rdma_peer_t **ompi_osc_rdma_get_peers (ompi_osc_rdma_module_t *m
     int *ranks1, *ranks2;
     int ret;
 
-    ranks1 = malloc (sizeof(int) * size);
-    ranks2 = malloc (sizeof(int) * size);
-    peers = malloc (sizeof (ompi_osc_rdma_peer_t *) * size);
+    ranks1 = calloc (size, sizeof(int));
+    ranks2 = calloc (size, sizeof(int));
+    peers = calloc (size, sizeof (ompi_osc_rdma_peer_t *));
     if (NULL == ranks1 || NULL == ranks2 || NULL == peers) {
         free (ranks1);
         free (ranks2);
         free (peers);
+        return NULL;
     }
 
     for (int i = 0 ; i < size ; ++i) {

ompi/mca/osc/rdma/osc_rdma_dynamic.c

@@ -231,7 +231,7 @@ int ompi_osc_rdma_detach (struct ompi_win_t *win, const void *base)
     OPAL_OUTPUT_VERBOSE((5, ompi_osc_base_framework.framework_output, "Detaching memory region %p-%p at index %d",
                          base, (void *)((intptr_t) base + region->len), region_index));
 
-    if (module->selected_btl && module->selected_btl->btl_register_mem) {
+    if (module->selected_btl->btl_register_mem) {
         ompi_osc_rdma_deregister (module, module->dynamic_handles[region_index].btl_handle);
 
         if (region_index < region_count - 1) {