diff --git a/utils/fwlog/dbglog_host.c b/utils/fwlog/dbglog_host.c
index 3feebd4d05..3382eac76d 100644
--- a/utils/fwlog/dbglog_host.c
+++ b/utils/fwlog/dbglog_host.c
@@ -1694,7 +1694,7 @@ process_fw_diag_event_data(uint8_t *datap, uint32_t num_data)
 	uint32_t diag_data_len; /* each fw diag payload */
 	struct wlan_diag_data *diag_data;
 
-	while (num_data > 0) {
+	while (num_data >= sizeof(struct wlan_diag_data)) {
 		diag_data = (struct wlan_diag_data *)datap;
 		diag_type = WLAN_DIAG_0_TYPE_GET(diag_data->word0);
 		diag_data_len = WLAN_DIAG_0_LEN_GET(diag_data->word0);