[compiler-rt][UBSan] Sanitization for alignment assumptions.
Summary:
This is the compiler-rt part.
The clang part is D54589.
This is a second commit, the original one was r351106,
which was mass-reverted in r351159 because 2 compiler-rt tests were failing.
Now, i have fundamentally changed the testing approach:
i malloc a few bytes, intentionally mis-align the pointer
(increment it by one), and check that. Also, i have decreased
the expected alignment. This hopefully should be enough to pacify
all the bots. If not, i guess i might just drop the two 'bad' tests.
Reviewers: filcab, vsk, #sanitizers, vitalybuka, rsmith, morehouse
Reviewed By: morehouse
Subscribers: rjmccall, krytarowski, rsmith, kcc, srhines, kubamracek, dberris, llvm-commits
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D54590
llvm-svn: 351178
diff --git a/compiler-rt/test/fuzzer/AlignmentAssumptionTest.cpp b/compiler-rt/test/fuzzer/AlignmentAssumptionTest.cpp
new file mode 100644
index 0000000..be51d37
--- /dev/null
+++ b/compiler-rt/test/fuzzer/AlignmentAssumptionTest.cpp
@@ -0,0 +1,27 @@
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+
+// Test for alignment assumption failure.
+
+#include <assert.h>
+#include <climits>
+#include <cstddef>
+#include <cstdint>
+#include <cstdlib>
+#include <iostream>
+
+static volatile int32_t Sink;
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+ assert(Data);
+ if (Size > 0 && Data[0] == 'H') {
+ Sink = 1;
+ if (Size > 1 && Data[1] == 'i') {
+ Sink = 2;
+ if (Size > 2 && Data[2] == '!') {
+ __builtin_assume_aligned(Data + 1, 0x8000);
+ }
+ }
+ }
+ return 0;
+}