diff --git a/radio/src/syscalls.c b/radio/src/syscalls.c
index 369566877..c9de63def 100644
--- a/radio/src/syscalls.c
+++ b/radio/src/syscalls.c
@@ -45,6 +45,24 @@ extern caddr_t _sbrk(int nbytes)
   }
 }
 
+#if defined(THREADSAFE_MALLOC) && !defined(BOOT)
+
+#include <FreeRTOS.h>
+#include <task.h>
+
+void __malloc_lock(struct _reent *r)
+{
+  (void)(r);
+  vTaskSuspendAll();
+};
+
+void __malloc_unlock(struct _reent *r)
+{
+  (void)(r);
+  (void)xTaskResumeAll();
+};
+#endif
+
 #if !defined(SEMIHOSTING)
 extern int _gettimeofday(void *p1, void *p2)
 {
diff --git a/radio/src/targets/horus/CMakeLists.txt b/radio/src/targets/horus/CMakeLists.txt
index a06854d91..91e2697ed 100644
--- a/radio/src/targets/horus/CMakeLists.txt
+++ b/radio/src/targets/horus/CMakeLists.txt
@@ -325,6 +325,9 @@ if (MULTIMODULE)
     )
 endif()
 
+# Make malloc() thread-safe
+add_definitions(-DTHREADSAFE_MALLOC)
+
 set(STM32LIB_SRC
   STM32F4xx_StdPeriph_Driver/src/stm32f4xx_sdio.c
   STM32F4xx_StdPeriph_Driver/src/stm32f4xx_fmc.c
diff --git a/radio/src/targets/nv14/CMakeLists.txt b/radio/src/targets/nv14/CMakeLists.txt
index db80a138c..f3b12d83d 100644
--- a/radio/src/targets/nv14/CMakeLists.txt
+++ b/radio/src/targets/nv14/CMakeLists.txt
@@ -161,6 +161,9 @@ if (MULTIMODULE)
     )
 endif()
 
+# Make malloc() thread-safe
+add_definitions(-DTHREADSAFE_MALLOC)
+
 set(STM32LIB_SRC
   STM32F4xx_StdPeriph_Driver/src/stm32f4xx_sdio.c
   STM32F4xx_StdPeriph_Driver/src/stm32f4xx_fmc.c