Add bpf2c fuzzer and execution context fuzzer to CI/CD

.github/workflows/cicd.yml

@@ -152,6 +152,33 @@ jobs:
       code_coverage: false
       gather_dumps: true
 
+  bpf2c_fuzzer:
+    needs: libfuzzer
+    # Always run this job.
+    if: github.event_name == 'schedule' || github.event_name == 'pull_request'
+    uses: ./.github/workflows/reusable-test.yml
+    with:
+      name: bpf2c_fuzzer
+      test_command: bpf2c_fuzzer.exe bpf2c_fuzzer_corpus -use_value_profile=1 -max_total_time=900 -artifact_prefix=Artifacts\
+      build_artifact: Build-x64-fuzzer
+      environment: windows-2019
+      code_coverage: false
+      gather_dumps: true
+
+  execution_context_fuzzer:
+    needs: libfuzzer
+    # Always run this job.
+    if: github.event_name == 'schedule' || github.event_name == 'pull_request'
+    uses: ./.github/workflows/reusable-test.yml
+    with:
+      name: execution_context_fuzzer
+      pre_test: powershell Expand-Archive -Path .\corpus.zip -DestinationPath execution_context_fuzzer_corpus -Force
+      test_command: execution_context_fuzzer.exe execution_context_fuzzer_corpus -use_value_profile=1 -runs=3000 -artifact_prefix=Artifacts\
+      build_artifact: Build-x64-fuzzer
+      environment: windows-2019
+      code_coverage: false
+      gather_dumps: true
+
   # Run Cilium regression tests in GitHub.
   cilium_tests:
     needs: regular

.github/workflows/reusable-test.yml

@@ -107,6 +107,10 @@ jobs:
         name: ${{inputs.build_artifact}} ${{matrix.configurations}}
         path: ${{github.workspace}}/${{env.BUILD_PLATFORM}}/${{env.BUILD_CONFIGURATION}}
 
+    - name: Create generated artifact folder
+      run: |
+        mkdir ${{github.workspace}}\${{env.BUILD_PLATFORM}}\${{env.BUILD_CONFIGURATION}}\Artifacts
+
     - name: Start ETW tracing
       id: start_etw_tracing
       if: inputs.capture_etw == true
@@ -242,6 +246,22 @@ jobs:
         path: ./${{env.BUILD_PLATFORM}}/${{env.BUILD_CONFIGURATION}}/TestLogs
         retention-days: 5
 
+    - name: Check for generated artifacts
+      if: always()
+      uses: andstor/file-existence-action@f02338908d150e00a4b8bebc2dad18bd9e5229b0
+      id: check_artifacts
+      with:
+        files: ${{github.workspace}}\${{env.BUILD_PLATFORM}}\${{env.BUILD_CONFIGURATION}}\Artifacts\*
+
+    - name: Upload generated artifacts
+      if: always() && steps.check_artifacts.outputs.files_exists == 'true'
+      id: upload_artifacts
+      uses: actions/upload-artifact@3cea5372237819ed00197afe530f5a7ea3e805c8
+      with:
+        name: Artifacts-${{env.NAME}}-${{env.BUILD_PLATFORM}}-${{env.BUILD_CONFIGURATION}}
+        path: ${{github.workspace}}\${{env.BUILD_PLATFORM}}\${{env.BUILD_CONFIGURATION}}\Artifacts
+        retention-days: 5
+
     - name: Mark run as failed if crash dumps are found
       if: steps.check_dumps.outputs.files_exists == 'true'
       run: exit 1

Directory.Build.props

@@ -12,9 +12,15 @@
   <PropertyGroup Condition="'$(AddressSanitizer)'=='True'">
     <EnableASAN>true</EnableASAN>
   </PropertyGroup>
-  <PropertyGroup Condition="'$(Fuzzer)'=='True'">
+  <PropertyGroup Condition="'$(Configuration)|$(Fuzzer)'=='Release|True'">
     <EnableASAN>true</EnableASAN>
     <AdditionalOptions>/fsanitize-coverage=inline-bool-flag /fsanitize-coverage=edge /fsanitize-coverage=trace-cmp /fsanitize-coverage=trace-div %(AdditionalOptions)</AdditionalOptions>
+    <SanitizerLibs>libsancov.lib;clang_rt.fuzzer_MD-x86_64.lib</SanitizerLibs>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Fuzzer)'=='Debug|True'">
+    <EnableASAN>true</EnableASAN>
+    <AdditionalOptions>/fsanitize-coverage=inline-bool-flag /fsanitize-coverage=edge /fsanitize-coverage=trace-cmp /fsanitize-coverage=trace-div %(AdditionalOptions)</AdditionalOptions>
+    <SanitizerLibs>libsancov.lib;clang_rt.fuzzer_MDd-x86_64.lib</SanitizerLibs>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Fuzzer)'!='True'">
     <SpectreMitigation>Spectre</SpectreMitigation>

ebpf-for-windows.sln

@@ -154,6 +154,9 @@ EndProject
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "execution_context_fuzzer", "tests\libfuzzer\execution_context\execution_context_fuzzer.vcxproj", "{6116AE11-5296-4DE9-8A8E-5380B789907E}"
 EndProject
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "bpf2c_fuzzer", "tests\libfuzzer\bpf2c\bpf2c_fuzzer.vcxproj", "{A0A0D663-DCF7-4BB1-9DDB-7964C3C31603}"
+	ProjectSection(ProjectDependencies) = postProject
+		{B4AD72E3-754E-40CA-9CEA-D3F2C9170E51} = {B4AD72E3-754E-40CA-9CEA-D3F2C9170E51}
+	EndProjectSection
 EndProject
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "verifier_fuzzer", "tests\libfuzzer\verifier\verifier_fuzzer.vcxproj", "{DCF12929-B975-4874-A80F-9EAF1CC5A5A0}"
 EndProject

ebpfapi/ebpfapi.vcxproj

@@ -80,8 +80,7 @@
       <EnableUAC>false</EnableUAC>
       <ModuleDefinitionFile>Source.def</ModuleDefinitionFile>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
-      <AdditionalDependencies>%(AdditionalDependencies)</AdditionalDependencies>
-      <AdditionalDependencies>mincore.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <AdditionalDependencies>$(SanitizerLibs);mincore.lib;%(AdditionalDependencies)</AdditionalDependencies>
     </Link>
     <ResourceCompile>
       <AdditionalIncludeDirectories>$(SolutionDir)include</AdditionalIncludeDirectories>
@@ -101,7 +100,7 @@
       <GenerateDebugInformation>DebugFull</GenerateDebugInformation>
       <EnableUAC>false</EnableUAC>
       <ModuleDefinitionFile>Source.def</ModuleDefinitionFile>
-      <AdditionalDependencies>mincore.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <AdditionalDependencies>$(SanitizerLibs);mincore.lib;%(AdditionalDependencies)</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>
     <ResourceCompile>

libs/platform/user/ebpf_platform_user.cpp

@@ -22,6 +22,7 @@ bool _ebpf_platform_code_integrity_enabled = false;
 bool _ebpf_platform_is_preemptible = true;
 
 extern "C" bool ebpf_fuzzing_enabled = false;
+extern "C" size_t ebfp_fuzzing_memory_limit = MAXSIZE_T;
 
 // Thread pool related globals.
 static TP_CALLBACK_ENVIRON _callback_environment;
@@ -243,6 +244,9 @@ __drv_allocatesMem(Mem) _Must_inspect_result_ _Ret_maybenull_
     _Post_writable_byte_size_(size) void* ebpf_allocate(size_t size)
 {
     ebpf_assert(size);
+    if (size > ebfp_fuzzing_memory_limit) {
+        return nullptr;
+    }
     void* memory;
     memory = calloc(size, 1);
     if (memory != nullptr)
@@ -255,6 +259,9 @@ __drv_allocatesMem(Mem) _Must_inspect_result_ _Ret_maybenull_
     _Post_writable_byte_size_(new_size) void* ebpf_reallocate(_In_ void* memory, size_t old_size, size_t new_size)
 {
     UNREFERENCED_PARAMETER(old_size);
+    if (new_size > ebfp_fuzzing_memory_limit) {
+        return nullptr;
+    }
     void* p = realloc(memory, new_size);
     if (p && (new_size > old_size))
         memset(((char*)p) + old_size, 0, new_size - old_size);
@@ -270,6 +277,10 @@ ebpf_free(_Frees_ptr_opt_ void* memory)
 __drv_allocatesMem(Mem) _Must_inspect_result_ _Ret_maybenull_
     _Post_writable_byte_size_(size) void* ebpf_allocate_cache_aligned(size_t size)
 {
+    if (size > ebfp_fuzzing_memory_limit) {
+        return nullptr;
+    }
+
     void* memory = _aligned_malloc(size, EBPF_CACHE_LINE_SIZE);
     if (memory) {
         memset(memory, 0, size);

scripts/create_bpf2c_corpus.bat

@@ -0,0 +1,10 @@
+@echo off
+rem Copyright (c) Microsoft Corporation
+rem SPDX-License-Identifier: MIT
+rem
+rem Usage: create_bpf2c_corpus.bat <output_directory>
+echo set OUTPUTPATH=%1
+set OUTPUTPATH=%1
+rem Strip the \ from the end of the path if present.
+if %OUTPUTPATH:~-1% EQU \ set OUTPUTPATH=%OUTPUTPATH:~0,-1%
+xcopy /d /i /y "%OUTPUTPATH%\*.o" "%OUTPUTPATH%\bpf2c_fuzzer_corpus"

tests/libfuzzer/bpf2c/bpf2c_fuzzer.vcxproj

@@ -89,6 +89,15 @@
       <Project>{7d5b4e68-c0fa-3f86-9405-f6400219b440}</Project>
     </ProjectReference>
   </ItemGroup>
+  <ItemGroup>
+    <CustomBuild Include="$(SolutionDir)scripts\create_bpf2c_corpus.bat">
+      <FileType>Document</FileType>
+      <Outputs Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">$(OutDir)bpf2c_fuzzer_corpus\bpf.o</Outputs>
+      <Outputs Condition="'$(Configuration)|$(Platform)'=='Release|x64'">$(OutDir)bpf2c_fuzzer_corpus\bpf.o</Outputs>
+      <Command Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">$(SolutionDir)scripts\create_bpf2c_corpus.bat $(OutDir)</Command>
+      <Command Condition="'$(Configuration)|$(Platform)'=='Release|x64'">$(SolutionDir)scripts\create_bpf2c_corpus.bat $(OutDir)</Command>
+    </CustomBuild>
+  </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>

tests/libfuzzer/bpf2c/bpf2c_fuzzer.vcxproj.filters

@@ -40,4 +40,9 @@
       <Filter>Header Files</Filter>
     </ClInclude>
   </ItemGroup>
+  <ItemGroup>
+    <CustomBuild Include="..\..\..\scripts\create_bpf2c_corpus.bat">
+      <Filter>Source Files</Filter>
+    </CustomBuild>
+  </ItemGroup>
 </Project>

tests/libfuzzer/execution_context/execution_context_fuzzer.vcxproj

@@ -96,6 +96,11 @@
     <ClInclude Include="..\..\libs\thunk\mock\mock.h" />
     <ClInclude Include="..\end_to_end\test_helper.hpp" />
   </ItemGroup>
+  <ItemGroup>
+    <CopyFileToFolders Include="corpus.zip">
+      <FileType>Document</FileType>
+    </CopyFileToFolders>
+  </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>

tests/libfuzzer/execution_context/execution_context_fuzzer.vcxproj.filters

@@ -31,4 +31,7 @@
       <Filter>Header Files</Filter>
     </ClInclude>
   </ItemGroup>
+  <ItemGroup>
+    <CopyFileToFolders Include="corpus.zip" />
+  </ItemGroup>
 </Project>

tests/libfuzzer/execution_context/libfuzz_harness.cpp

@@ -21,6 +21,8 @@
 #include "libfuzzer.h"
 #include "platform.h"
 
+extern "C" size_t ebfp_fuzzing_memory_limit;
+
 static std::vector<std::unique_ptr<_program_info_provider>> _program_information_providers;
 static std::vector<GUID> _program_types = {
     EBPF_PROGRAM_TYPE_XDP,
@@ -236,7 +238,11 @@ fuzz_ioctl(std::vector<uint8_t>& random_buffer)
     }
 }
 
-FUZZ_EXPORT int __cdecl LLVMFuzzerInitialize(int*, char***) { return 0; }
+FUZZ_EXPORT int __cdecl LLVMFuzzerInitialize(int*, char***)
+{
+    ebfp_fuzzing_memory_limit = 1024 * 1024 * 10;
+    return 0;
+}
 
 FUZZ_EXPORT int __cdecl LLVMFuzzerTestOneInput(const uint8_t* data, size_t size)
 {

tools/bpf2c/bpf2c.vcxproj

@@ -120,6 +120,7 @@
     <Link>
       <SubSystem>Console</SubSystem>
       <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>$(SanitizerLibs);%(AdditionalDependencies)</AdditionalDependencies>
     </Link>
     <PreBuildEvent>
       <Command>powershell -NonInteractive -ExecutionPolicy Unrestricted $(SolutionDir)scripts\Process-File.ps1 -InputFile Convert-BpfToNative.ps1.template -OutputFile $(OutDir)Convert-BpfToNative.ps1 -ConfigFile replacements.json</Command>
@@ -137,6 +138,7 @@
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
       <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>$(SanitizerLibs);%(AdditionalDependencies)</AdditionalDependencies>
     </Link>
     <PreBuildEvent>
       <Command>powershell -NonInteractive -ExecutionPolicy Unrestricted $(SolutionDir)scripts\Process-File.ps1 -InputFile Convert-BpfToNative.ps1.template -OutputFile $(OutDir)Convert-BpfToNative.ps1 -ConfigFile replacements.json</Command>

tools/bpf2c/bpf_code_generator.cpp

@@ -246,6 +246,7 @@ bpf_code_generator::parse()
 
     if (map_section) {
         size_t data_size = map_section->get_size();
+        size_t map_count = data_size / sizeof(ebpf_map_definition_in_file_t);
 
         if (data_size % sizeof(ebpf_map_definition_in_file_t) != 0) {
             throw std::runtime_error(
@@ -276,12 +277,23 @@ bpf_code_generator::parse()
                 if (symbol_size != sizeof(ebpf_map_definition_in_file_t)) {
                     throw std::runtime_error("invalid map size");
                 }
+                if (symbol_value > map_section->get_size()) {
+                    throw std::runtime_error("invalid symbol value");
+                }
+                if ((symbol_value + symbol_size) > map_section->get_size()) {
+                    throw std::runtime_error("invalid symbol value");
+                }
+
                 map_definitions[symbol_name].definition =
                     *reinterpret_cast<const ebpf_map_definition_in_file_t*>(map_section->get_data() + symbol_value);
 
                 map_definitions[symbol_name].index = symbol_value / sizeof(ebpf_map_definition_in_file_t);
             }
         }
+
+        if (map_definitions.size() != map_count) {
+            throw std::runtime_error(std::string("bad maps section, map must have associated symbol"));
+        }
     }
 }