1//===-- lldb-target-fuzzer.cpp --------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "utils/TempFile.h"
10
11#include "Plugins/Platform/Linux/PlatformLinux.h"
12#include "lldb/Core/Debugger.h"
13#include "lldb/Core/Value.h"
14#include "lldb/Expression/DWARFExpression.h"
15#include "lldb/Host/FileSystem.h"
16#include "lldb/Host/HostInfo.h"
17#include "lldb/Target/Target.h"
18
19using namespace lldb;
20using namespace lldb_private;
21using namespace lldb_private::plugin::dwarf;
22using namespace lldb_fuzzer;
23
24extern "C" int LLVMFuzzerInitialize(int *argc, char ***argv) {
25 FileSystem::Initialize();
26 HostInfo::Initialize();
27 platform_linux::PlatformLinux::Initialize();
28 return 0;
29}
30
31static void Evaluate(llvm::ArrayRef<uint8_t> expr,
32 lldb::ModuleSP module_sp = {}, DWARFUnit *unit = nullptr,
33 ExecutionContext *exe_ctx = nullptr) {
34 DataExtractor extractor(expr.data(), expr.size(), lldb::eByteOrderLittle,
35 /*addr_size*/ 4);
36
37 llvm::Expected<Value> result =
38 DWARFExpression::Evaluate(exe_ctx, /*reg_ctx*/ nullptr, module_sp,
39 opcodes: extractor, dwarf_cu: unit, reg_set: lldb::eRegisterKindLLDB,
40 /*initial_value_ptr*/ nullptr,
41 /*object_address_ptr*/ nullptr);
42
43 if (!result)
44 llvm::consumeError(Err: result.takeError());
45}
46
47class MockTarget : public Target {
48public:
49 MockTarget(Debugger &debugger, const ArchSpec &target_arch,
50 const lldb::PlatformSP &platform_sp, llvm::ArrayRef<uint8_t> data)
51 : Target(debugger, target_arch, platform_sp, true), m_data(data) {}
52
53 size_t ReadMemory(const Address &addr, void *dst, size_t dst_len,
54 Status &error, bool force_live_memory = false,
55 lldb::addr_t *load_addr_ptr = nullptr) override {
56 std::memcpy(dest: dst, src: m_data.data(), n: m_data.size());
57 return m_data.size();
58 }
59
60private:
61 llvm::ArrayRef<uint8_t> m_data;
62};
63
64extern "C" int LLVMFuzzerTestOneInput(uint8_t *data, size_t size) {
65 // We're going to use the first half of the input data as the DWARF expression
66 // and the second half as memory.
67 const size_t partition = size / 2;
68 llvm::ArrayRef expression_data(data, partition);
69 llvm::ArrayRef memory_data(data + partition, size - partition);
70
71 // Create a mock target for reading memory.
72 ArchSpec arch("i386-pc-linux");
73 Platform::SetHostPlatform(
74 platform_linux::PlatformLinux::CreateInstance(true, &arch));
75 lldb::DebuggerSP debugger_sp = Debugger::CreateInstance();
76 lldb::PlatformSP platform_sp;
77 auto target_sp = std::make_shared<MockTarget>(args&: *debugger_sp, args&: arch, args&: platform_sp,
78 args&: memory_data);
79 ExecutionContext exe_ctx(static_cast<lldb::TargetSP>(target_sp), false);
80
81 Evaluate(expr: expression_data);
82 return 0;
83}
84

source code of lldb/tools/lldb-fuzzer/lldb-dwarf-expression-fuzzer/lldb-dwarf-expression-fuzzer.cpp