[libFuzzer] Update Load test to work on 32 bits.

We should ensure the size of the variable `a` is 8 bytes. Otherwise, this
generates a stack buffer overflow inside the memcpy call in 32 bits machines.
(We write more bytes than the size of a, when it is 4 bytes)

Differential Revision: https://reviews.llvm.org/D29602

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294378 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Fuzzer/test/LoadTest.cpp b/lib/Fuzzer/test/LoadTest.cpp
index c1780d5..eef16c7 100644 (file)
--- a/lib/Fuzzer/test/LoadTest.cpp
+++ b/lib/Fuzzer/test/LoadTest.cpp
@@ -14,7 +14,7 @@ int array[kArraySize];
 
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
   if (Size < 8) return 0;
-  size_t a = 0;
+  uint64_t a = 0;
   memcpy(&a, Data, 8);
   Sink = array[a % (kArraySize + 1)];
   return 0;