diff --git a/components/bt/host/bluedroid/hci/hci_hal_h4.c b/components/bt/host/bluedroid/hci/hci_hal_h4.c
index ae51b55dcd..a1f12bb9bf 100644
--- a/components/bt/host/bluedroid/hci/hci_hal_h4.c
+++ b/components/bt/host/bluedroid/hci/hci_hal_h4.c
@@ -34,7 +34,6 @@
 #include "esp_bt.h"
 #endif
 #include "esp_bluedroid_hci.h"
-#include "stack/hcimsgs.h"
 
 #if (C2H_FLOW_CONTROL_INCLUDED == TRUE)
 #include "l2c_int.h"
@@ -319,9 +318,12 @@ static void hci_packet_complete(BT_HDR *packet){
 }
 #endif ///C2H_FLOW_CONTROL_INCLUDED == TRUE
 
-bool host_recv_adv_packet(uint8_t *packet)
+bool host_recv_adv_packet(uint8_t *packet, uint16_t len)
 {
     assert(packet);
+    if (len < 4) {
+        return false;
+    }
     if(packet[0] == DATA_TYPE_EVENT && packet[1] == HCI_BLE_EVENT) {
         if(packet[3] ==  HCI_BLE_ADV_PKT_RPT_EVT || packet[3] == HCI_BLE_DIRECT_ADV_EVT
 #if (BLE_ADV_REPORT_FLOW_CONTROL == TRUE)
@@ -543,7 +545,7 @@ static void hci_hal_h4_hdl_rx_adv_rpt(pkt_linked_item_t *linked_pkt)
     BT_HDR* packet = (BT_HDR *)linked_pkt->data;
     stream = packet->data + packet->offset;
 
-    assert(host_recv_adv_packet(stream) == true);
+    assert(host_recv_adv_packet(stream, packet->len) == true);
 
     STREAM_TO_UINT8(type, stream);
     packet->offset++;
@@ -588,7 +590,10 @@ static void host_send_pkt_available_cb(void)
 void bt_record_hci_data(uint8_t *data, uint16_t len)
 {
 #if (BT_HCI_LOG_INCLUDED == TRUE)
-    if ((data[0] == DATA_TYPE_EVENT) && (data[1] == HCI_BLE_EVENT) && ((data[3] ==  HCI_BLE_ADV_PKT_RPT_EVT) || (data[3] == HCI_BLE_DIRECT_ADV_EVT)
+    if (len < 2) {
+        return;
+    }
+    if ((len >= 4) && (data[0] == DATA_TYPE_EVENT) && (data[1] == HCI_BLE_EVENT) && ((data[3] ==  HCI_BLE_ADV_PKT_RPT_EVT) || (data[3] == HCI_BLE_DIRECT_ADV_EVT)
 #if (BLE_ADV_REPORT_FLOW_CONTROL == TRUE)
         || (data[3] ==  HCI_BLE_ADV_DISCARD_REPORT_EVT)
 #endif // (BLE_ADV_REPORT_FLOW_CONTROL == TRUE)
@@ -641,7 +646,7 @@ static int host_recv_pkt_cb(uint8_t *data, uint16_t len)
     }
 #endif // #if (BLE_FEAT_ISO_EN == TRUE)
 
-    bool is_adv_rpt = host_recv_adv_packet(data);
+    bool is_adv_rpt = host_recv_adv_packet(data, len);
 
     if (!is_adv_rpt) {
         pkt_size = BT_HDR_SIZE + len;
@@ -700,7 +705,7 @@ static int host_recv_pkt_cb(uint8_t *data, uint16_t len)
 
     hci_upstream_data_post(OSI_THREAD_MAX_TIMEOUT);
 
-    BTTRC_DUMP_BUFFER("Recv Pkt", pkt->data, len);
+    BTTRC_DUMP_BUFFER("Recv Pkt", data, len);
 
     return 0;
 }
diff --git a/components/bt/host/bluedroid/hci/hci_layer.c b/components/bt/host/bluedroid/hci/hci_layer.c
index fbc0dab461..ac56596667 100644
--- a/components/bt/host/bluedroid/hci/hci_layer.c
+++ b/components/bt/host/bluedroid/hci/hci_layer.c
@@ -117,7 +117,7 @@ int hci_start_up(void)
     hci_host_thread = osi_thread_create(HCI_HOST_TASK_NAME, HCI_HOST_TASK_STACK_SIZE, HCI_HOST_TASK_PRIO, HCI_HOST_TASK_PINNED_TO_CORE,
                                         HCI_HOST_TASK_WORKQUEUE_NUM, workqueue_len);
     if (hci_host_thread == NULL) {
-        return -2;
+        goto error;
     }
 
     osi_event_bind(hci_host_env.downstream_data_ready, hci_host_thread, HCI_DOWNSTREAM_DATA_QUEUE_IDX);
@@ -137,13 +137,15 @@ error:
 void hci_shut_down(void)
 {
     hci_host_startup_flag  = false;
+
+    /* Close HAL and cleanup before freeing thread: hal->open() and osi_event_bind()
+     * stored references to hci_host_thread; they must not use it after osi_thread_free(). */
+    if (hci_host_thread != NULL) {
+        hal->close();
+        packet_fragmenter->cleanup();
+    }
     hci_layer_deinit_env();
 
-    packet_fragmenter->cleanup();
-
-    //low_power_manager->cleanup();
-    hal->close();
-
     osi_thread_free(hci_host_thread);
     hci_host_thread = NULL;
 }
@@ -445,7 +447,7 @@ static bool filter_incoming_event(BT_HDR *packet)
 {
     pkt_linked_item_t *wait_entry = NULL;
     hci_cmd_metadata_t *metadata = NULL;
-    uint8_t *stream = packet->data + packet->offset;
+    uint8_t *stream;
     uint8_t event_code;
     command_opcode_t opcode;
 
@@ -453,6 +455,8 @@ static bool filter_incoming_event(BT_HDR *packet)
         return true;
     }
 
+    stream = packet->data + packet->offset;
+
     if (packet->len < HCI_EVENT_PREAMBLE_SIZE) {
         HCI_TRACE_WARNING("dropping too short HCI event (len=%u)", packet->len);
         osi_free(packet);
diff --git a/components/bt/host/bluedroid/hci/hci_packet_factory.c b/components/bt/host/bluedroid/hci/hci_packet_factory.c
index 6a84f9ca29..f710046d0e 100644
--- a/components/bt/host/bluedroid/hci/hci_packet_factory.c
+++ b/components/bt/host/bluedroid/hci/hci_packet_factory.c
@@ -250,6 +250,8 @@ static BT_HDR *make_command_no_params(uint16_t opcode)
 static BT_HDR *make_command(uint16_t opcode, size_t parameter_size, uint8_t **stream_out)
 {
     BT_HDR *packet = HCI_GET_CMD_BUF(parameter_size);
+    assert(packet != NULL);
+
     hci_cmd_metadata_t *metadata = HCI_GET_CMD_METAMSG(packet);
     metadata->opcode = opcode;
 
diff --git a/components/bt/host/bluedroid/hci/packet_fragmenter.c b/components/bt/host/bluedroid/hci/packet_fragmenter.c
index 0827ecb4fe..e280a98183 100644
--- a/components/bt/host/bluedroid/hci/packet_fragmenter.c
+++ b/components/bt/host/bluedroid/hci/packet_fragmenter.c
@@ -73,9 +73,10 @@ static void fragment_and_dispatch(BT_HDR *packet)
     uint16_t continuation_handle;
     uint16_t max_data_size, max_packet_size, remaining_length;
     uint16_t event = packet->event & MSG_EVT_MASK;
-    uint8_t *stream = packet->data + packet->offset;
+    uint8_t *stream;
 
     assert(packet != NULL);
+    stream = packet->data + packet->offset;
 
     // We only fragment ACL packets
     if (event != MSG_STACK_TO_HC_HCI_ACL) {