It's still better to strdup at least topic.

Author: FedeDP

Lib/module.c

@@ -330,7 +330,7 @@ int flush_pubsub_msg(void *data, void *m) {
             const msg_t msg = { .is_pubsub = 1, .pubsub_msg = mm };
             mod->hook.recv(&msg, mod->userdata);
         }
-        memhook._free(mm);
+        destroy_pubsub_msg(mm);
     }
     return 0;
 }
@@ -362,13 +362,18 @@ static pubsub_msg_t *create_pubsub_msg(const unsigned char *message, const self_
     if (m) {
         m->message = message;
         m->sender = sender;
-        m->topic = topic;
+        m->topic = mem_strdup(topic);
         *(int *)&m->type = type;
         *(size_t *)&m->size = size;
     }
     return m;
 }
 
+void destroy_pubsub_msg(pubsub_msg_t *m) {
+    memhook._free((char *)m->topic);
+    memhook._free(m);
+}
+
 static module_ret_code tell_pubsub_msg(pubsub_msg_t *m, module *mod, m_context *c) {
     if (mod) {
         tell_if(m, mod);

Lib/module_priv.h

@@ -73,6 +73,7 @@ typedef struct {
 int evaluate_module(void *data, void *m);
 module_ret_code tell_system_pubsub_msg(m_context *c, enum msg_type type, const char *topic);
 int flush_pubsub_msg(void *data, void *m);
+void destroy_pubsub_msg(pubsub_msg_t *m);
 char *mem_strdup(const char *s);
 
 extern map_t ctx;

Lib/modules.c

@@ -89,7 +89,7 @@ module_ret_code modules_ctx_loop_events(const char *ctx_name, const int max_even
 
                 /* Properly free pubsub msg */
                 if (p->fd == mod->pubsub_fd[0]) {
-                    memhook._free((void *)msg.pubsub_msg);
+                    destroy_pubsub_msg((pubsub_msg_t *)msg.pubsub_msg);
                 }
             }
             evaluate_new_state(c);

TODO.md

@@ -2,7 +2,6 @@
 
 - [x] pubsub messaging to send bytes instead of string (ie: add size to pubsub_msg_t)
 - [x] Avoid strdup for pubsub msg and trust user-provided pointer
-- [x] Same as above for topic
 - [x] Use memhook malloc/free in epoll_priv, kqueue_priv poll_set_data()
 - [x] Avoid strdup and use internal strdup that makes use of memhook
 - [x] modules_quit should take an "exit value" parameter

docs/src/pubsub.rst

@@ -32,4 +32,4 @@ PubSub notes
 Note that a context must be looping to receive any pubsub message. |br|
 Moreover, when a context stops looping, all pubsub messages will be flushed and thus delivered to each RUNNING module. |br|
 Pubsub message sent while context is not looping are buffered until context starts looping. For more information, see `pipe capacity <https://linux.die.net/man/7/pipe>`_. |br|
-Finally, please be aware that both data and topic sent through pubsub messaging are trusted, ie: you should pay attention to their scopes.
+Finally, please be aware that data pointer sent through pubsub messaging is trusted, ie: you should pay attention to its scope.