diff --git a/src/rp2_common/pico_cyw43_driver/cybt_shared_bus/cybt_shared_bus.c b/src/rp2_common/pico_cyw43_driver/cybt_shared_bus/cybt_shared_bus.c
index 5649c00..b464b3f 100644
--- a/src/rp2_common/pico_cyw43_driver/cybt_shared_bus/cybt_shared_bus.c
+++ b/src/rp2_common/pico_cyw43_driver/cybt_shared_bus/cybt_shared_bus.c
@@ -62,14 +62,14 @@
     *p_write_buf = NULL;
     *p_hex_buf = NULL;
 
-    *p_write_buf = malloc(BTFW_DOWNLOAD_BLK_SIZE + BTFW_SD_ALIGN);
+    *p_write_buf = cyw43_malloc(BTFW_DOWNLOAD_BLK_SIZE + BTFW_SD_ALIGN);
     if (NULL == *p_write_buf) {
         return CYBT_ERR_OUT_OF_MEMORY;
     }
 
-    *p_hex_buf = malloc(BTFW_MAX_STR_LEN);
+    *p_hex_buf = cyw43_malloc(BTFW_MAX_STR_LEN);
     if (NULL == *p_hex_buf) {
-        free(*p_write_buf);
+        cyw43_free(*p_write_buf);
         return CYBT_ERR_OUT_OF_MEMORY;
     }
 
@@ -78,11 +78,11 @@
 
 static cybt_result_t cybt_fw_download_finish(uint8_t *p_write_buf, uint8_t *p_hex_buf) {
     if (p_write_buf) {
-        free(p_write_buf);
+        cyw43_free(p_write_buf);
     }
 
     if (p_hex_buf) {
-        free(p_hex_buf);
+        cyw43_free(p_hex_buf);
     }
 
     return CYBT_SUCCESS;
diff --git a/src/rp2_common/pico_cyw43_driver/include/cyw43_configport.h b/src/rp2_common/pico_cyw43_driver/include/cyw43_configport.h
index 0526291..f012d24 100644
--- a/src/rp2_common/pico_cyw43_driver/include/cyw43_configport.h
+++ b/src/rp2_common/pico_cyw43_driver/include/cyw43_configport.h
@@ -157,6 +157,14 @@
 
 #define CYW43_POST_POLL_HOOK cyw43_post_poll_hook();
 
+// Allow malloc and free to be changed
+#ifndef cyw43_malloc
+#define cyw43_malloc malloc
+#endif
+#ifndef cyw43_free
+#define cyw43_free free
+#endif
+
 #ifdef __cplusplus
 }
 #endif