diff --git a/core/include/oneway_malloc.h b/core/include/oneway_malloc.h
index 6a8df5f8e7..56daf2cc80 100644
--- a/core/include/oneway_malloc.h
+++ b/core/include/oneway_malloc.h
@@ -12,6 +12,7 @@
 #include <stddef.h>
 
 void* _malloc(size_t size);
+void* _realloc(void *ptr, size_t size);
 void _free (void* ptr);
 
 /** @} */
diff --git a/core/oneway_malloc.c b/core/oneway_malloc.c
index 51d6d53967..10c76c9c38 100644
--- a/core/oneway_malloc.c
+++ b/core/oneway_malloc.c
@@ -35,6 +35,13 @@ void *_malloc(size_t size) {
     }
 }
 
+void *_realloc(void *ptr, size_t size) {
+    void* newptr = _malloc(size);
+    memcpy(newptr, ptr, size);
+    free(ptr);
+    return newptr;
+}
+
 void _free(void* ptr) {
     DEBUG("_free(): block at 0x%X lost.\n", (unsigned int)ptr);
 }
diff --git a/cpu/msp430/include/malloc.h b/cpu/msp430/include/malloc.h
index faddc99715..2ab076c6a3 100644
--- a/cpu/msp430/include/malloc.h
+++ b/cpu/msp430/include/malloc.h
@@ -4,6 +4,7 @@
 #include "oneway_malloc.h"
 
 #define malloc _malloc
+#define realloc _realloc
 #define free _free
 
 #endif /* __MALLOC_H */