[llvm] [MC] AsmLexer assert buffer is null-terminated at CurBuf.end() (PR #154972)

[Szymon Piotr Milczek via llvm-commits]

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@@ -0,0 +1,61 @@
+//===- llvm/unittest/Object/Disassembler.cpp ------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCParser/MCAsmParser.h"
+#include "llvm/MC/MCParser/AsmLexer.h"
+#include "llvm/MC/MCInstPrinter.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/MC/MCTargetOptions.h"
+#include "llvm/MC/TargetRegistry.h"
+#include "llvm/Support/TargetSelect.h"
+#include "llvm/Target/TargetMachine.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+
+namespace {
+class MCAsmParserTest : public ::testing::Test {
+public:
+  std::unique_ptr<MCRegisterInfo> MRI;
+  std::unique_ptr<MCAsmInfo> MAI;
+
+  MCAsmParserTest() {
+    llvm::InitializeAllTargetInfos();
+    llvm::InitializeAllTargetMCs();
+
+    StringRef TripleName = "x86_64-pc-linux";
+    Triple TT(TripleName);
+    std::string ErrorStr;
+
+    const Target *TheTarget = TargetRegistry::lookupTarget(TT, ErrorStr);
+
+    // If we didn't build x86, do not run the test.
+    if (!TheTarget)
+      return;
+
+    MRI.reset(TheTarget->createMCRegInfo(TT));
+    MCTargetOptions MCOptions;
+    MAI.reset(TheTarget->createMCAsmInfo(*MRI, TT, MCOptions));
+  }
+};
+} // namespace
+
+TEST_F(MCAsmParserTest, InvalidRead) {
+  AsmLexer Lexer(*MAI);
+  const char* Source = "ret\0 ";
+  StringRef SourceRef(Source, 4); // Include null terminator in buffer length
+  Lexer.setBuffer(SourceRef);
+
+  bool Error = false;
+  while (Lexer.Lex().isNot(AsmToken::Eof)) {
+    if (Lexer.getTok().getKind() == AsmToken::Error)
+      Error = true;
+  }
+  ASSERT_TRUE(Error == false);
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smilczek wrote:

unittest removed in 92a16a4013290f12ce3abaa9da3ce965edcde8ae

https://github.com/llvm/llvm-project/pull/154972