diff --git a/lib/core/ogs-3gpp-types.c b/lib/core/ogs-3gpp-types.c
index e143cb078..23445da22 100644
--- a/lib/core/ogs-3gpp-types.c
+++ b/lib/core/ogs-3gpp-types.c
@@ -748,7 +748,7 @@ static int flow_rx_to_gx(ogs_flow_t *rx_flow, ogs_flow_t *gx_flow)
         /* 'permit in' should be changed
          * 'permit out' in Gx Diameter */
         len = strlen(rx_flow->description)+2;
-        gx_flow->description = ogs_malloc(len);
+        gx_flow->description = ogs_calloc(1, len);
         ogs_assert(gx_flow->description);
         strcpy(gx_flow->description, "permit out");
         from_str = strstr(&rx_flow->description[strlen("permit in")], "from");
diff --git a/lib/dbi/session.c b/lib/dbi/session.c
index 0291f6e79..d0edb7218 100644
--- a/lib/dbi/session.c
+++ b/lib/dbi/session.c
@@ -455,7 +455,7 @@ done:
                                     BSON_ITER_HOLDS_UTF8(&child8_iter)) {
                                     utf8 = bson_iter_utf8(
                                             &child8_iter, &length);
-                                    flow->description = ogs_malloc(length+1);
+                                    flow->description = ogs_calloc(1, length+1);
                                     ogs_assert(flow->description);
                                     ogs_cpystrn((char*)flow->description,
                                         utf8, length+1);
diff --git a/lib/pfcp/handler.c b/lib/pfcp/handler.c
index c0346d5ff..265ecb01e 100644
--- a/lib/pfcp/handler.c
+++ b/lib/pfcp/handler.c
@@ -363,8 +363,8 @@ ogs_pfcp_pdr_t *ogs_pfcp_handle_create_pdr(ogs_pfcp_sess_t *sess,
         if (rule->fd) {
             char *flow_description = NULL;
 
-            flow_description = ogs_malloc(
-                    sdf_filter.flow_description_len+1);
+            flow_description = ogs_calloc(
+                    1, sdf_filter.flow_description_len+1);
             ogs_assert(flow_description);
             ogs_cpystrn(flow_description,
                     sdf_filter.flow_description,
@@ -616,8 +616,8 @@ ogs_pfcp_pdr_t *ogs_pfcp_handle_update_pdr(ogs_pfcp_sess_t *sess,
             if (rule->fd) {
                 char *flow_description = NULL;
 
-                flow_description = ogs_malloc(
-                        sdf_filter.flow_description_len+1);
+                flow_description = ogs_calloc(
+                        1, sdf_filter.flow_description_len+1);
                 ogs_assert(flow_description);
                 ogs_cpystrn(flow_description,
                         sdf_filter.flow_description,
diff --git a/src/pcrf/pcrf-rx-path.c b/src/pcrf/pcrf-rx-path.c
index cc87a9ffe..7ef6a7cb8 100644
--- a/src/pcrf/pcrf-rx-path.c
+++ b/src/pcrf/pcrf-rx-path.c
@@ -323,26 +323,27 @@ static int pcrf_rx_aar_cb( struct msg **msg, struct avp *avp,
                                         "permit out", strlen("permit out"))) {
 
                                     to_ip = strstr(to_str, " ");
-                                    if (to_ip != NULL) {
-                                        // Exclude the starting whitespace
-                                        to_ip += 1;
+                                    ogs_assert(to_ip);
 
-                                        to_port = strstr(to_ip, " ");
-                                        // Test for no port
-                                        if (to_port != NULL) {
-                                            flow->description = ogs_malloc(len
-                                                - strlen(to_str) +
-                                                strlen("to any")
-                                                + strlen(to_port) + 1);
-                                            ogs_assert(flow->description);
-                                        } else {
-                                            flow->description = ogs_malloc(len
-                                                - strlen(to_str) +
-                                                strlen("to any") + 1);
-                                            ogs_assert(flow->description);
-                                        }
+                                    // Exclude the starting whitespace
+                                    to_ip += 1;
+
+                                    to_port = strstr(to_ip, " ");
+                                    // Test for no port
+                                    if (to_port != NULL) {
+                                        flow->description = ogs_calloc(1,
+                                            len - strlen(to_str) +
+                                            strlen("to any")
+                                            + strlen(to_port) + 1);
+                                        ogs_assert(flow->description);
+                                    } else {
+                                        flow->description = ogs_calloc(1,
+                                            len - strlen(to_str) +
+                                            strlen("to any") + 1);
+                                        ogs_assert(flow->description);
                                     }
 
+                                    ogs_assert(flow->description);
                                     strncat(flow->description,
                                         rx_flow,
                                         len - strlen(to_str));
@@ -355,32 +356,33 @@ static int pcrf_rx_aar_cb( struct msg **msg, struct avp *avp,
                                             "permit in", strlen("permit in"))) {
 
                                     from_ip = strstr(from_str, " ");
-                                    if (from_ip != NULL) {
-                                        /* Exclude the starting whitespace */
-                                        from_ip += 1;
+                                    ogs_assert(from_ip);
 
-                                        from_port = strstr(from_ip, " ");
-                                        /* Test for no port +
-                                         * whether from_port is at "to"
-                                         * without any from port */
-                                        if (from_port != NULL &&
-                                            strncmp(from_port, " to", 3)) {
-                                            flow->description = ogs_malloc(
-                                                len - strlen(from_str) +
-                                                strlen(to_str)
-                                                + strlen("from any") + 1
-                                                + (strlen(from_port) -
-                                                    strlen(to_str)));
-                                            ogs_assert(flow->description);
-                                        } else {
-                                            flow->description = ogs_malloc(
-                                                len - strlen(from_str) +
-                                                strlen(to_str)
-                                                + strlen("from any ") + 1);
-                                            ogs_assert(flow->description);
-                                        }
+                                    /* Exclude the starting whitespace */
+                                    from_ip += 1;
+
+                                    from_port = strstr(from_ip, " ");
+                                    /* Test for no port +
+                                     * whether from_port is at "to"
+                                     * without any from port */
+                                    if (from_port != NULL &&
+                                        strncmp(from_port, " to", 3)) {
+                                        flow->description = ogs_calloc(1,
+                                            len - strlen(from_str) +
+                                            strlen(to_str)
+                                            + strlen("from any") + 1
+                                            + (strlen(from_port) -
+                                                strlen(to_str)));
+                                        ogs_assert(flow->description);
+                                    } else {
+                                        flow->description = ogs_calloc(1,
+                                            len - strlen(from_str) +
+                                            strlen(to_str)
+                                            + strlen("from any ") + 1);
+                                        ogs_assert(flow->description);
                                     }
 
+                                    ogs_assert(flow->description);
                                     strncat(flow->description,
                                         rx_flow,
                                         len - strlen(from_str));
diff --git a/src/smf/gsm-sm.c b/src/smf/gsm-sm.c
index 931106c7a..118e33a31 100644
--- a/src/smf/gsm-sm.c
+++ b/src/smf/gsm-sm.c
@@ -190,15 +190,8 @@ void smf_gsm_state_operational(ogs_fsm_t *s, smf_event_t *e)
                                     smf_ue->supi, sess->psi,
                                     sbi_message->res_status);
                             ogs_assert(strerror);
-
                             ogs_error("%s", strerror);
-                            if (stream)
-                                ogs_assert(true ==
-                                    ogs_sbi_server_send_error(stream,
-                                        sbi_message->res_status,
-                                        sbi_message, strerror, NULL));
                             ogs_free(strerror);
-                            break;
                         }
 
                         smf_npcf_smpolicycontrol_handle_delete(