[llvm] [WebAssembly] Limit increase of Ctx.End (PR #76676)

[David Blaikie via llvm-commits]

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@@ -0,0 +1,32 @@
+//===-- ObjectFuzzRegressions.cpp - Fuzz regression checking -------------===//
+//
+// 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/Object/ObjectFile.h"
+#include "llvm/Testing/Support/Error.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+using namespace llvm::object;
+
+TEST(ObjectFuzzRegressions, OSSFUZZ30308) {
+  // Regression test for
+  // https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=30308
+  const uint8_t data[47] = {
+      0x00, 0x61, 0x73, 0x6d, 0x01, 0x00, 0x00, 0x00, 0x00, 0x10, 0x07, 0x6c,
+      0x69, 0x6e, 0x6b, 0x69, 0x6e, 0x67, 0x02, 0x08, 0xe2, 0x29, 0x01, 0x01,
+      0x02, 0xea, 0x06, 0xf9, 0xee, 0x28, 0xe1, 0x2b, 0x2f, 0x09, 0x00, 0xef,
+      0xbf, 0xbf, 0x00, 0x00, 0xdd, 0x73, 0x66, 0x83, 0x7b, 0x00, 0x55};
+
+  std::string Payload(reinterpret_cast<const char *>(data), 47);
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dwblaikie wrote:

Perhaps use sizeof(data) to avoid the magic number here? 

https://github.com/llvm/llvm-project/pull/76676