handle fread return value

Author: AmyrAhmady

src/node.cc

@@ -1055,9 +1055,11 @@ std::unique_ptr<InitializationResult> InitializeOncePerProcess(
 #if defined(__linux__)
       FILE* urandom = fopen("/dev/urandom", "rb");
       if (urandom) {
-          fread(seed, 1, sizeof(seed), urandom);
-          fclose(urandom);
+        size_t bytes_read = fread(seed, 1, sizeof(seed), urandom);
+        if (bytes_read == sizeof(seed)) {
           RAND_seed(seed, sizeof(seed));
+        }
+        fclose(urandom);
       }
 #endif
     }