From 7a963ddc4f6484dcfcb97f99263e7d9fef7ac781 Mon Sep 17 00:00:00 2001
From: Marc Lasch <marc.lasch@husqvarnagroup.com>
Date: Tue, 30 Aug 2022 08:32:23 +0200
Subject: [PATCH] coap: Cleanup transactions when client is unregistered

All pending transactions of a just unregistered client must be removed
---
 coap/transaction.c        | 19 +++++++++++++++++++
 core/liblwm2m.c           |  2 +-
 core/registration.c       |  8 +++++---
 include/liblwm2m.h        |  5 +++++
 tests/helper/connection.c |  7 +++++++
 5 files changed, 37 insertions(+), 4 deletions(-)

diff --git a/coap/transaction.c b/coap/transaction.c
index 01a5bf092..7aa9518fa 100644
--- a/coap/transaction.c
+++ b/coap/transaction.c
@@ -527,3 +527,22 @@ bool transaction_free_userData(lwm2m_context_t * context, lwm2m_transaction_t *
     transaction->userData = NULL;
     return true;
 }
+
+/*
+ * Remove transactions from a specific client.
+ */
+void transaction_remove_client(lwm2m_context_t *contextP, lwm2m_client_t *clientP) {
+    lwm2m_transaction_t *transacP;
+
+    LOG("Entering");
+    transacP = contextP->transactionList;
+    while (transacP != NULL) {
+        lwm2m_transaction_t *nextP = transacP->next;
+
+        if (lwm2m_session_is_equal(transacP->peerH, clientP->sessionH, contextP->userData)) {
+            LOG("Found session to remove");
+            transaction_remove(contextP, transacP);
+        }
+        transacP = nextP;
+    }
+}
diff --git a/core/liblwm2m.c b/core/liblwm2m.c
index 2bff2833e..515df5d48 100644
--- a/core/liblwm2m.c
+++ b/core/liblwm2m.c
@@ -218,7 +218,7 @@ void lwm2m_close(lwm2m_context_t * contextP)
         clientP = contextP->clientList;
         contextP->clientList = contextP->clientList->next;
 
-        registration_freeClient(clientP);
+        registration_freeClient(contextP, clientP);
     }
 #endif
 
diff --git a/core/registration.c b/core/registration.c
index 5bafc6679..04c416449 100644
--- a/core/registration.c
+++ b/core/registration.c
@@ -1744,6 +1744,8 @@ void registration_freeClient(lwm2m_client_t * clientP)
 
         free_block_data(targetP);
     }
+    transaction_remove_client(contextP, clientP);
+    lwm2m_session_remove(clientP->sessionH);
     lwm2m_free(clientP);
 }
 
@@ -1858,7 +1860,7 @@ uint8_t  registration_handleRequest(lwm2m_context_t * contextP,
                 {
                     lwm2m_client_t * tmpClientP = utils_findClient(contextP, fromSessionH);
                     contextP->clientList = (lwm2m_client_t *)LWM2M_LIST_RM(contextP->clientList, tmpClientP->internalID, &tmpClientP);
-                    registration_freeClient(tmpClientP);
+                    registration_freeClient(contextP, tmpClientP);
                 }
             }
             if (clientP != NULL)
@@ -1898,12 +1900,12 @@ uint8_t  registration_handleRequest(lwm2m_context_t * contextP,
 
             if (prv_getLocationString(clientP->internalID, location) == 0)
             {
-                registration_freeClient(clientP);
+                registration_freeClient(contextP, clientP);
                 return COAP_500_INTERNAL_SERVER_ERROR;
             }
             if (coap_set_header_location_path(response, location) == 0)
             {
-                registration_freeClient(clientP);
+                registration_freeClient(contextP, clientP);
                 return COAP_500_INTERNAL_SERVER_ERROR;
             }
 
diff --git a/include/liblwm2m.h b/include/liblwm2m.h
index 16039418c..a77010d4f 100644
--- a/include/liblwm2m.h
+++ b/include/liblwm2m.h
@@ -157,6 +157,11 @@ uint8_t lwm2m_buffer_send(void * sessionH, uint8_t * buffer, size_t length, void
 // userData: parameter to lwm2m_init()
 bool lwm2m_session_is_equal(void * session1, void * session2, void * userData);
 
+/*
+ * Remove session from list
+ */
+void lwm2m_session_remove(void *sessionH);
+
 /*
  * Error code
  */
diff --git a/tests/helper/connection.c b/tests/helper/connection.c
index d7b2d91a7..2a9a48521 100644
--- a/tests/helper/connection.c
+++ b/tests/helper/connection.c
@@ -50,3 +50,10 @@ uint8_t *test_get_response_buffer(size_t *len) {
     *len = response_len;
     return response_buffer;
 }
+
+void lwm2m_session_remove(void *sessionH) {
+    (void)sessionH;
+
+    // Currently the tests do not use a session structure, assume a NULL pointer here.
+    assert(sessionH == NULL);
+}