Fix: used wrong variable in malloc.

Author: fangerer

graalpython/com.oracle.graal.python.cext/src/capi.c

@@ -266,7 +266,7 @@ const char* PyTruffle_StringToCstr(void* o, int32_t strLen) {
 const char* PyTruffle_ByteArrayToNative(const void* jbyteArray, int len) {
     int i;
     int size = len != 0 ? len : 1;
-    char* barr = (const char*) malloc(len * sizeof(char));
+    char* barr = (const char*) malloc(size * sizeof(char));
     barr[0] = '\0';
     for(i=0; i < len; i++) {
         barr[i] = (char) polyglot_get_array_element(jbyteArray, i);