auth: Handle empty lists of keys

Handle the case where a list of keys may be empty - don't attempt
to calloc a 0 length array, and have Put handle the case where the
array being freed has no elements.

Caught by clang-analyzer

Change-Id: I665035cb00a8da411710a71a17ae66545702127f
Reviewed-on: http://gerrit.openafs.org/7098
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>

diff --git a/src/auth/keys.c b/src/auth/keys.c
index c02fec6..52d1265 100644 (file)
--- a/src/auth/keys.c
+++ b/src/auth/keys.c
@@ -81,15 +81,20 @@ listToArray(struct kvnoList *kvnoEntry, struct afsconf_typedKeyList **keys)
     /* Allocate space for the keys we've got stored */
     retval = malloc(sizeof(struct afsconf_typedKeyList));
     retval->nkeys = opr_queue_Count(&kvnoEntry->subTypeList);
-    retval->keys  = calloc(retval->nkeys, sizeof(struct afsconf_typedKey *));
 
-    i = 0;
-    for(opr_queue_Scan(&kvnoEntry->subTypeList, cursor)) {
-       struct subTypeList *entry;
+    if (retval->nkeys > 0) {
+        retval->keys  = calloc(retval->nkeys, sizeof(struct afsconf_typedKey *));
 
-       entry = opr_queue_Entry(cursor, struct subTypeList, link);
-       retval->keys[i] = afsconf_typedKey_get(entry->key);
-       i++;
+       i = 0;
+        for(opr_queue_Scan(&kvnoEntry->subTypeList, cursor)) {
+           struct subTypeList *entry;
+
+           entry = opr_queue_Entry(cursor, struct subTypeList, link);
+           retval->keys[i] = afsconf_typedKey_get(entry->key);
+           i++;
+        }
+    } else {
+       retval->keys = NULL;
     }
 
     *keys = retval;
@@ -848,20 +853,29 @@ afsconf_GetAllKeys(struct afsconf_dir *dir, struct afsconf_typedKeyList **keys)
     /* Allocate space for all of these */
     retval = malloc(sizeof(struct afsconf_typedKeyList));
     retval->nkeys = count;
-    retval->keys = calloc(retval->nkeys, sizeof(struct afsconf_typedKey *));
 
-    /* Populate the key list */
-    count = 0;
-    for (opr_queue_Scan(&dir->keyList, typeCursor)) {
-       typeEntry = opr_queue_Entry(typeCursor, struct keyTypeList, link);
-       for (opr_queue_Scan(&typeEntry->kvnoList, kvnoCursor)) {
-           kvnoEntry = opr_queue_Entry(kvnoCursor, struct kvnoList, link);
-           for (opr_queue_Scan(&kvnoEntry->subTypeList, subCursor)) {
-               subEntry = opr_queue_Entry(subCursor, struct subTypeList, link);
-               retval->keys[count] = afsconf_typedKey_get(subEntry->key);
-               count++;
+    if (count > 0) {
+       retval->keys = calloc(retval->nkeys,
+                             sizeof(struct afsconf_typedKey *));
+
+       /* Populate the key list */
+        count = 0;
+       for (opr_queue_Scan(&dir->keyList, typeCursor)) {
+           typeEntry = opr_queue_Entry(typeCursor,
+                                       struct keyTypeList, link);
+           for (opr_queue_Scan(&typeEntry->kvnoList, kvnoCursor)) {
+               kvnoEntry = opr_queue_Entry(kvnoCursor,
+                                           struct kvnoList, link);
+               for (opr_queue_Scan(&kvnoEntry->subTypeList, subCursor)) {
+                   subEntry = opr_queue_Entry(subCursor,
+                                              struct subTypeList, link);
+                   retval->keys[count] = afsconf_typedKey_get(subEntry->key);
+                   count++;
+               }
            }
        }
+    } else {
+       retval->keys = NULL;
     }
 
     *keys = retval;
@@ -993,7 +1007,10 @@ afsconf_PutTypedKeyList(struct afsconf_typedKeyList **keys)
 
      for (i=0;i<(*keys)->nkeys;i++)
        afsconf_typedKey_put(&((*keys)->keys[i]));
-     free((*keys)->keys);
+
+     if ((*keys)->keys != NULL)
+       free((*keys)->keys);
+
      free(*keys);
      *keys = NULL;
 }