diff --git a/lib/core/ogs-pkbuf.c b/lib/core/ogs-pkbuf.c
index a283ff24b..ed7048622 100644
--- a/lib/core/ogs-pkbuf.c
+++ b/lib/core/ogs-pkbuf.c
@@ -318,7 +318,6 @@ ogs_pkbuf_t *ogs_pkbuf_copy_debug(ogs_pkbuf_t *pkbuf, const char *file_line)
     newbuf = ogs_pkbuf_alloc_debug(NULL, size, file_line);
     if (!newbuf) {
         ogs_error("ogs_pkbuf_alloc() failed [size=%d]", size);
-        ogs_pkbuf_free(pkbuf);
         return NULL;
     }
 
@@ -345,7 +344,6 @@ ogs_pkbuf_t *ogs_pkbuf_copy_debug(ogs_pkbuf_t *pkbuf, const char *file_line)
     ogs_pool_alloc(&pool->pkbuf, &newbuf);
     if (!newbuf) {
         ogs_error("ogs_pkbuf_copy() failed");
-        ogs_pkbuf_free(pkbuf);
         ogs_thread_mutex_unlock(&pool->mutex);
         return NULL;
     }
diff --git a/src/amf/nas-path.c b/src/amf/nas-path.c
index b667a17d3..262834299 100644
--- a/src/amf/nas-path.c
+++ b/src/amf/nas-path.c
@@ -108,6 +108,7 @@ int nas_5gs_send_registration_accept(amf_ue_t *amf_ue)
         amf_ue->t3550.pkbuf = ogs_pkbuf_copy(gmmbuf);
         if (!amf_ue->t3550.pkbuf) {
             ogs_error("ogs_pkbuf_copy(amf_ue->t3550.pkbuf) failed");
+            ogs_pkbuf_free(gmmbuf);
             return OGS_ERROR;
         }
         ogs_timer_start(amf_ue->t3550.timer,
@@ -373,6 +374,7 @@ int nas_5gs_send_de_registration_request(amf_ue_t *amf_ue,
     amf_ue->t3522.pkbuf = ogs_pkbuf_copy(gmmbuf);
     if (!amf_ue->t3522.pkbuf) {
         ogs_error("ogs_pkbuf_copy(amf_ue->t3522.pkbuf) failed");
+        ogs_pkbuf_free(gmmbuf);
         return OGS_ERROR;
     }
     ogs_timer_start(amf_ue->t3522.timer,
@@ -406,6 +408,7 @@ int nas_5gs_send_identity_request(amf_ue_t *amf_ue)
     amf_ue->t3570.pkbuf = ogs_pkbuf_copy(gmmbuf);
     if (!amf_ue->t3570.pkbuf) {
         ogs_error("ogs_pkbuf_copy(amf_ue->t3570.pkbuf) failed");
+        ogs_pkbuf_free(gmmbuf);
         return OGS_ERROR;
     }
     ogs_timer_start(amf_ue->t3570.timer,
@@ -439,6 +442,7 @@ int nas_5gs_send_authentication_request(amf_ue_t *amf_ue)
     amf_ue->t3560.pkbuf = ogs_pkbuf_copy(gmmbuf);
     if (!amf_ue->t3560.pkbuf) {
         ogs_error("ogs_pkbuf_copy(amf_ue->t3560.pkbuf) failed");
+        ogs_pkbuf_free(gmmbuf);
         return OGS_ERROR;
     }
     ogs_timer_start(amf_ue->t3560.timer,
@@ -495,6 +499,7 @@ int nas_5gs_send_security_mode_command(amf_ue_t *amf_ue)
     amf_ue->t3560.pkbuf = ogs_pkbuf_copy(gmmbuf);
     if (!amf_ue->t3560.pkbuf) {
         ogs_error("ogs_pkbuf_copy(amf_ue->t3560.pkbuf) failed");
+        ogs_pkbuf_free(gmmbuf);
         return OGS_ERROR;
     }
     ogs_timer_start(amf_ue->t3560.timer,
@@ -522,6 +527,7 @@ int nas_5gs_send_configuration_update_command(
         amf_ue->t3555.pkbuf = ogs_pkbuf_copy(gmmbuf);
         if (!amf_ue->t3555.pkbuf) {
             ogs_error("ogs_pkbuf_copy(amf_ue->t3555.pkbuf) failed");
+            ogs_pkbuf_free(gmmbuf);
             return OGS_ERROR;
         }
         ogs_timer_start(amf_ue->t3555.timer,
@@ -542,6 +548,7 @@ int nas_5gs_send_configuration_update_command(
             amf_ue->t3555.pkbuf = ogs_pkbuf_copy(gmmbuf);
             if (!amf_ue->t3555.pkbuf) {
                 ogs_error("ogs_pkbuf_copy(amf_ue->t3555.pkbuf) failed");
+                ogs_pkbuf_free(gmmbuf);
                 return OGS_ERROR;
             }
             ogs_timer_start(amf_ue->t3555.timer,
diff --git a/src/amf/ngap-path.c b/src/amf/ngap-path.c
index 5f8c3898a..873f61497 100644
--- a/src/amf/ngap-path.c
+++ b/src/amf/ngap-path.c
@@ -409,6 +409,7 @@ int ngap_send_paging(amf_ue_t *amf_ue)
                     amf_ue->t3513.pkbuf = ogs_pkbuf_copy(ngapbuf);
                     if (!amf_ue->t3513.pkbuf) {
                         ogs_error("ogs_pkbuf_copy() failed");
+                        ogs_pkbuf_free(ngapbuf);
                         return OGS_ERROR;
                     }
 
diff --git a/src/mme/emm-sm.c b/src/mme/emm-sm.c
index b0d6dd189..570069818 100644
--- a/src/mme/emm-sm.c
+++ b/src/mme/emm-sm.c
@@ -1243,7 +1243,11 @@ void emm_state_initial_context_setup(ogs_fsm_t *s, mme_event_t *e)
                 }
 
                 mme_ue->t3450.pkbuf = ogs_pkbuf_copy(emmbuf);
-                ogs_assert(mme_ue->t3450.pkbuf);
+                if (!mme_ue->t3450.pkbuf) {
+                    ogs_error("ogs_pkbuf_copy() failed");
+                    ogs_pkbuf_free(emmbuf);
+                    return;
+                }
 
                 ogs_timer_start(mme_ue->t3450.timer,
                         mme_timer_cfg(MME_TIMER_T3450)->duration);
diff --git a/src/mme/nas-path.c b/src/mme/nas-path.c
index b26fbea85..275917ea7 100644
--- a/src/mme/nas-path.c
+++ b/src/mme/nas-path.c
@@ -139,6 +139,7 @@ int nas_eps_send_attach_accept(mme_ue_t *mme_ue)
     mme_ue->t3450.pkbuf = ogs_pkbuf_copy(emmbuf);
     if (!mme_ue->t3450.pkbuf) {
         ogs_error("ogs_pkbuf_copy(mme_ue->t3450.pkbuf) failed");
+        ogs_pkbuf_free(emmbuf);
         return OGS_ERROR;
     }
     ogs_timer_start(mme_ue->t3450.timer,
@@ -215,6 +216,7 @@ int nas_eps_send_identity_request(mme_ue_t *mme_ue)
     mme_ue->t3470.pkbuf = ogs_pkbuf_copy(emmbuf);
     if (!mme_ue->t3470.pkbuf) {
         ogs_error("ogs_pkbuf_copy(mme_ue->t3470.pkbuf) failed");
+        ogs_pkbuf_free(emmbuf);
         return OGS_ERROR;
     }
     ogs_timer_start(mme_ue->t3470.timer, 
@@ -248,6 +250,7 @@ int nas_eps_send_authentication_request(mme_ue_t *mme_ue)
     mme_ue->t3460.pkbuf = ogs_pkbuf_copy(emmbuf);
     if (!mme_ue->t3460.pkbuf) {
         ogs_error("ogs_pkbuf_copy(mme_ue->t3460.pkbuf) failed");
+        ogs_pkbuf_free(emmbuf);
         return OGS_ERROR;
     }
     ogs_timer_start(mme_ue->t3460.timer, 
@@ -281,6 +284,7 @@ int nas_eps_send_security_mode_command(mme_ue_t *mme_ue)
     mme_ue->t3460.pkbuf = ogs_pkbuf_copy(emmbuf);
     if (!mme_ue->t3460.pkbuf) {
         ogs_error("ogs_pkbuf_copy(mme_ue->t3460.pkbuf) failed");
+        ogs_pkbuf_free(emmbuf);
         return OGS_ERROR;
     }
     ogs_timer_start(mme_ue->t3460.timer, 
@@ -333,6 +337,7 @@ int nas_eps_send_detach_request(mme_ue_t *mme_ue)
     mme_ue->t3422.pkbuf = ogs_pkbuf_copy(emmbuf);
     if (!mme_ue->t3422.pkbuf) {
         ogs_error("ogs_pkbuf_copy(mme_ue->t3422.pkbuf) failed");
+        ogs_pkbuf_free(emmbuf);
         return OGS_ERROR;
     }
     ogs_timer_start(mme_ue->t3422.timer, 
@@ -446,6 +451,7 @@ int nas_eps_send_esm_information_request(mme_bearer_t *bearer)
     bearer->t3489.pkbuf = ogs_pkbuf_copy(esmbuf);
     if (!bearer->t3489.pkbuf) {
         ogs_error("ogs_pkbuf_copy(bearer->t3489) failed");
+        ogs_pkbuf_free(esmbuf);
         return OGS_ERROR;
     }
     ogs_timer_start(bearer->t3489.timer, 
@@ -669,6 +675,7 @@ int nas_eps_send_tau_accept(
         mme_ue->t3450.pkbuf = ogs_pkbuf_copy(emmbuf);
         if (!mme_ue->t3450.pkbuf) {
             ogs_error("ogs_pkbuf_copy(mme_ue->t3450.pkbuf) failed");
+            ogs_pkbuf_free(emmbuf);
             return OGS_ERROR;
         }
         ogs_timer_start(mme_ue->t3450.timer,
diff --git a/src/mme/s1ap-path.c b/src/mme/s1ap-path.c
index 5ed5b54da..766ca067c 100644
--- a/src/mme/s1ap-path.c
+++ b/src/mme/s1ap-path.c
@@ -400,6 +400,7 @@ int s1ap_send_paging(mme_ue_t *mme_ue, S1AP_CNDomain_t cn_domain)
                 mme_ue->t3413.pkbuf = ogs_pkbuf_copy(s1apbuf);
                 if (!mme_ue->t3413.pkbuf) {
                     ogs_error("ogs_pkbuf_copy() failed");
+                    ogs_pkbuf_free(s1apbuf);
                     return OGS_ERROR;
                 }