Make the RE2 fuzzer ignore overly large inputs.

Change-Id: I069a4d138cbe9313ee5402f268e8f732422ed5f8
Reviewed-on: https://code-review.googlesource.com/5504
Reviewed-by: Paul Wankadia <junyer@google.com>
diff --git a/re2/fuzzing/re2_fuzzer.cc b/re2/fuzzing/re2_fuzzer.cc
index 6fd8699..a6e44ca 100644
--- a/re2/fuzzing/re2_fuzzer.cc
+++ b/re2/fuzzing/re2_fuzzer.cc
@@ -51,7 +51,7 @@
 
 // Entry point for libFuzzer.
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
-  if (size == 0)
+  if (size == 0 || size > 1000000)
     return 0;
 
   // Suppress logging below FATAL severity.