Added missing check for replay protection pointer before allocating n…

…ew variable

Problem: If a key with write-once flag is being set in a SecureStore without rollback-protection store (i.e. _rbp_kv == NULL), additional memory will be allocated for the variable _ih->key. The memory will not be deleted, though, as the delete in line 434 only happens if a rollback-protection store exists (i.e. _rbp_kv != NULL)

Solution: Only allocate the memory if _rbp_kv != NULL

Contribution is provided on behalf of BIOTRONIK.

storage/kvstore/securestore/source/SecureStore.cpp

@@ -290,7 +290,7 @@ int SecureStore::set_start(set_handle_t *handle, const char *key, size_t final_d
         goto fail;
     }
 
-    if (create_flags & (REQUIRE_REPLAY_PROTECTION_FLAG | WRITE_ONCE_FLAG)) {
+    if (_rbp_kv && (create_flags & (REQUIRE_REPLAY_PROTECTION_FLAG | WRITE_ONCE_FLAG))) {
         _ih->key = new char[strlen(key) + 1];
         strcpy(_ih->key, key);
     }