Add CFI integer types normalization

[rcvalle]

Summary

This commit adds a new option (i.e.,
-fsanitize-cfi-icall-normalize-integers) for normalizing integer types
as vendor extended types for cross-language LLVM CFI/KCFI support with
other languages that can't represent and encode C/C++ integer types.

Specifically, integer types are encoded as their defined representations
(e.g., 8-bit signed integer, 16-bit signed integer, 32-bit signed
integer, ...) for compatibility with languages that define
explicitly-sized integer types (e.g., i8, i16, i32, ..., in Rust).

`-fsanitize-cfi-icall-normalize-integers` is compatible with
`-fsanitize-cfi-icall-generalize-pointers`.

This helps with providing cross-language CFI support with the Rust
compiler and is an alternative solution for the issue described and
alternatives proposed in the RFC
https://github.com/rust-lang/rfcs/pull/3296.

For more information about LLVM CFI/KCFI and cross-language LLVM
CFI/KCFI support for the Rust compiler, see the design document in the
tracking issue https://github.com/rust-lang/rust/issues/89653.

[rcvalle]

Fixed typo in commit message

[ojeda]

Cc @nickdesaulniers @nathanchance

[rcvalle]

FYI, I'll still add (hopefully today) documentation for the new -fsanitize-cfi-icall-normalize-integers option and compression for these types.

[rcvalle]

Added documentation

[rcvalle]

Added compression

[rcvalle]

Fixed comments

[rcvalle]

Updated tests

[rcvalle]

Added ".normalized" suffix

[nickdesaulniers]

Thanks for the patch and the work on cross language CFI support!

I wonder if we have precedent for other non-standard extensions to ItaniumMangleContextImpl? I wonder if we should perhaps have a distinct subclass to denote that this is not the standard mangling scheme. It would be nice perhaps to get this standardized in https://itanium-cxx-abi.github.io/cxx-abi/abi.html#mangling.
https://github.com/itanium-cxx-abi/cxx-abi

cc @rjmccall @hjl.tools

[pcc]

A high level question is whether we want to base the cross-language encoding on Itanium at all. Itanium has concepts such as substitutions that will complicate the implementation in other languages. Encoding pointee types can also lead to complications in cross-language encodings.

It may be better to consider developing a custom encoding. For the encoding being prototyped for the pointer authentication ABI on Android, the Rust side of the implementation is very simple:

https://github.com/pcc/rust/blob/d37ad119171635219ff21e054780d31024d24200/compiler/rustc_ty_utils/src/abi.rs#L396

clang/lib/AST/ItaniumMangle.cpp

2952

isInteger() will return true for enums, but only if they are complete. This would mean that code such as

void (*f)(enum E *e);

void g() {
  f(0);
}

would use a different encoding to call f depending on whether the TU completes the enum E, if pointee types are considered part of the encoding.

[rcvalle]

I elaborated on the reasons why not use a generalized encoding in the design document in the tracking issue https://github.com/rust-lang/rust/issues/89653. The tl;dr; is that it will result in less comprehensive protection by either using a generalized encoding for all C and C++ -compiled code or across the FFI boundary, and will degrade the security of the program when linking foreign Rust-compiled code into a program written in C or C++ because the program previously used a more comprehensive encoding for all its compiled code, not fixing the issue described in the design document and the RFC https://github.com/rcvalle/rfcs/blob/improve-c-types-for-cross-language-cfi/text/0000-improve-c-types-for-cross-language-cfi.md#appendix.

[rcvalle]

clang/lib/AST/ItaniumMangle.cpp

2952

Isn't isIntegerType() that does that? isInteger() definition is:

bool isInteger() const {
  return getKind() >= Bool && getKind() <= Int128;
}

[pcc]

In D139395#3990772, @rcvalle wrote:

I elaborated on the reasons why not use a generalized encoding in the design document in the tracking issue https://github.com/rust-lang/rust/issues/89653. The tl;dr; is that it will result in less comprehensive protection by either using a generalized encoding for all C and C++ -compiled code or across the FFI boundary, and will degrade the security of the program when linking foreign Rust-compiled code into a program written in C or C++ because the program previously used a more comprehensive encoding for all its compiled code, not fixing the issue described in the design document and the RFC https://github.com/rcvalle/rfcs/blob/improve-c-types-for-cross-language-cfi/text/0000-improve-c-types-for-cross-language-cfi.md#appendix.

Ack.

clang/lib/AST/ItaniumMangle.cpp

2952

Ah yes, sorry, somehow I read this as a call to isIntegerType().

[rcvalle]

Updated tests

[rcvalle]

Added KCFI support

[samitolvanen]

Thanks for the patch, Ramon. This looks like a reasonable approach to me, and just for reference, here appears to be the corresponding rustc change:

https://github.com/rust-lang/rust/pull/105452/commits/9087c336103d0fa0b465acf8dbc1e4651250fb05

@pcc did you have any other concerns about adding this option?

[pcc]

In D139395#4066948, @samitolvanen wrote:

Thanks for the patch, Ramon. This looks like a reasonable approach to me, and just for reference, here appears to be the corresponding rustc change:

https://github.com/rust-lang/rust/pull/105452/commits/9087c336103d0fa0b465acf8dbc1e4651250fb05

@pcc did you have any other concerns about adding this option?

I discussed this out of band with Ramon and we agreed that the new option should be marked as experimental because the rustc implementation is not yet finalized. I think that the criteria for removing the experimental marking should be that there is a full implementation of integer normalization for Rust (or some other language) that has been tested against a large codebase that uses FFI. Aside from that I have no further concerns.

[rcvalle]

Mark as experimental

[samitolvanen]

In D139395#4067391, @pcc wrote:

I discussed this out of band with Ramon and we agreed that the new option should be marked as experimental because the rustc implementation is not yet finalized. I think that the criteria for removing the experimental marking should be that there is a full implementation of integer normalization for Rust (or some other language) that has been tested against a large codebase that uses FFI.

Sure, that makes sense.

clang/docs/ControlFlowIntegrity.rst

241

An extra dash in the title.

[rcvalle]

Fixed typo

[rcvalle]

clang/docs/ControlFlowIntegrity.rst

241

Fixed. Thank you!

[samitolvanen]

Thanks, LGTM. @pcc, does this version look fine to you?

[pcc]

LGTM with nits

clang/lib/CodeGen/CodeGenModule.cpp

1694

Is the !! necessary here?

6881

Likewise

clang/test/CodeGen/cfi-icall-normalize.c

55–75

Shouldn't these all be checking for specific types? Since you're specifying a triple, the width and signedness of the integer types are fixed.

clang/test/CodeGen/cfi-icall-normalize2.c

9

Likewise; also below

[rcvalle]

Changed as per review

[rcvalle]

clang/lib/CodeGen/CodeGenModule.cpp

1694

Fixed. Thank you!

6881

Fixed. Thank you!

clang/test/CodeGen/cfi-icall-normalize.c

55–75

Fixed. Thank you!

clang/test/CodeGen/cfi-icall-normalize2.c

9

Fixed. Thank you!

[pcc]

LGTM

[hctim]

Hey folks, looks like this caused a failure on the msan buildbot: https://lab.llvm.org/buildbot/#/builders/237/builds/785

It's been had a long-running bug that I'm still tracking down but seems like this is a new failure caused by this patch. The track-origins log is copied below for your convenience.

The bot can be reproduced by following the instructions at https://github.com/google/sanitizers/wiki/SanitizerBotReproduceBuild, you'd want to substitute buildbot_fast.sh for buildbot_bootstrap_msan.sh though. Given the bot is already red when this was committed, please ignore any failures other than this one.

==3442210==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0xaaaaf388495c in (anonymous namespace)::CXXNameMangler::mangleUnqualifiedName(clang::GlobalDecl, clang::DeclarationName, clang::DeclContext const*, unsigned int, llvm::SmallVector<llvm::StringRef, 4u> const*) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/AST/ItaniumMangle.cpp:1631:9
    #1 0xaaaaf389ab8c in mangleUnqualifiedName /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/AST/ItaniumMangle.cpp:501:5
    #2 0xaaaaf389ab8c in (anonymous namespace)::CXXNameMangler::mangleNestedName(clang::GlobalDecl, clang::DeclContext const*, llvm::SmallVector<llvm::StringRef, 4u> const*, bool) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/AST/ItaniumMangle.cpp:1735:5
    #3 0xaaaaf3847b20 in (anonymous namespace)::CXXNameMangler::mangleFunctionEncoding(clang::GlobalDecl) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/AST/ItaniumMangle.cpp:811:5
    #4 0xaaaaf38985fc in (anonymous namespace)::CXXNameMangler::mangleLocalName(clang::GlobalDecl, llvm::SmallVector<llvm::StringRef, 4u> const*) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/AST/ItaniumMangle.cpp:1806:7
    #5 0xaaaaf3897d00 in (anonymous namespace)::CXXNameMangler::mangleType(clang::TagType const*) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/AST/ItaniumMangle.cpp:3468:3
    #6 0xaaaaf384e184 in (anonymous namespace)::CXXNameMangler::mangleType(clang::QualType) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/AST/ItaniumMangle.cpp
    #7 0xaaaaf384106c in (anonymous namespace)::ItaniumMangleContextImpl::mangleCXXRTTIName(clang::QualType, llvm::raw_ostream&, bool) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/AST/ItaniumMangle.cpp:6626:11
    #8 0xaaaaeb77c768 in clang::CodeGen::CodeGenTBAA::getBaseTypeInfoHelper(clang::Type const*) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenTBAA.cpp:394:16
    #9 0xaaaaeb777978 in getBaseTypeInfo /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenTBAA.cpp:427:28
    #10 0xaaaaeb777978 in clang::CodeGen::CodeGenTBAA::getTypeInfo(clang::QualType) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenTBAA.cpp:242:12
    #11 0xaaaaeb779184 in clang::CodeGen::CodeGenTBAA::getAccessInfo(clang::QualType) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenTBAA.cpp:265:25
    #12 0xaaaaeb0c2cfc in MakeAddrLValue /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenFunction.h:2494:33
    #13 0xaaaaeb0c2cfc in (anonymous namespace)::AggExprEmitter::VisitLambdaExpr(clang::LambdaExpr*) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGExprAgg.cpp:1350:23
    #14 0xaaaaeb0ab220 in Visit /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGExprAgg.cpp:108:34
    #15 0xaaaaeb0ab220 in clang::CodeGen::CodeGenFunction::EmitAggExpr(clang::Expr const*, clang::CodeGen::AggValueSlot) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGExprAgg.cpp:2038:49
    #16 0xaaaaea90e15c in clang::CodeGen::CodeGenFunction::EmitAnyExpr(clang::Expr const*, clang::CodeGen::AggValueSlot, bool) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGExpr.cpp:224:5
    #17 0xaaaaea910c80 in clang::CodeGen::CodeGenFunction::EmitAnyExprToTemp(clang::Expr const*) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGExpr.cpp:237:10
    #18 0xaaaaeac28f4c in clang::CodeGen::CodeGenFunction::EmitCallArg(clang::CodeGen::CallArgList&, clang::Expr const*, clang::QualType) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGCall.cpp:4461:12
    #19 0xaaaaeac25c34 in clang::CodeGen::CodeGenFunction::EmitCallArgs(clang::CodeGen::CallArgList&, clang::CodeGen::CodeGenFunction::PrototypeWrapper, llvm::iterator_range<clang::Stmt::CastIterator<clang::Expr, clang::Expr const* const, clang::Stmt const* const>>, clang::CodeGen::CodeGenFunction::AbstractCallee, unsigned int, clang::CodeGen::CodeGenFunction::EvaluationOrder) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGCall.cpp:4308:5
    #20 0xaaaaea9733d0 in clang::CodeGen::CodeGenFunction::EmitCall(clang::QualType, clang::CodeGen::CGCallee const&, clang::CallExpr const*, clang::CodeGen::ReturnValueSlot, llvm::Value*) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGExpr.cpp:5435:3
    #21 0xaaaaea970394 in clang::CodeGen::CodeGenFunction::EmitCallExpr(clang::CallExpr const*, clang::CodeGen::ReturnValueSlot) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGExpr.cpp:4999:10
    #22 0xaaaaeacbeb28 in (anonymous namespace)::ScalarExprEmitter::VisitCallExpr(clang::CallExpr const*) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGExprScalar.cpp:580:20
    #23 0xaaaaeac88628 in Visit /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGExprScalar.cpp:407:52
    #24 0xaaaaeac88628 in clang::CodeGen::CodeGenFunction::EmitScalarExpr(clang::Expr const*, bool) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGExprScalar.cpp:5044:8
    #25 0xaaaaea90d7ac in clang::CodeGen::CodeGenFunction::EvaluateExprAsBool(clang::Expr const*) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGExpr.cpp:183:33
    #26 0xaaaaea9a2dc0 in clang::CodeGen::CodeGenFunction::EmitBranchOnBoolExpr(clang::Expr const*, llvm::BasicBlock*, llvm::BasicBlock*, unsigned long, clang::Stmt::Likelihood) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenFunction.cpp:1883:13
    #27 0xaaaaea9d3f04 in clang::CodeGen::CodeGenFunction::EmitIfStmt(clang::IfStmt const&) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGStmt.cpp:833:3
    #28 0xaaaaea9d2888 in EmitCompoundStmtWithoutScope /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGStmt.cpp:535:7
    #29 0xaaaaea9d2888 in EmitCompoundStmt /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGStmt.cpp:486:10
    #30 0xaaaaea9d2888 in clang::CodeGen::CodeGenFunction::EmitSimpleStmt(clang::Stmt const*, llvm::ArrayRef<clang::Attr const*>) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGStmt.cpp:442:5
    #31 0xaaaaea9d0c74 in clang::CodeGen::CodeGenFunction::EmitStmt(clang::Stmt const*, llvm::ArrayRef<clang::Attr const*>) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGStmt.cpp:59:7
    #32 0xaaaaeac5614c in clang::CodeGen::CodeGenFunction::EmitConstructorBody(clang::CodeGen::FunctionArgList&) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGClass.cpp
    #33 0xaaaaea99f2c8 in clang::CodeGen::CodeGenFunction::GenerateCode(clang::GlobalDecl, llvm::Function*, clang::CodeGen::CGFunctionInfo const&) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenFunction.cpp:1439:5
    #34 0xaaaaeb174904 in clang::CodeGen::CodeGenModule::codegenCXXStructor(clang::GlobalDecl) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CGCXX.cpp:215:26
    #35 0xaaaaea8a2024 in (anonymous namespace)::ItaniumCXXABI::emitCXXStructor(clang::GlobalDecl) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/ItaniumCXXABI.cpp:4375:28
    #36 0xaaaaea7893f8 in clang::CodeGen::CodeGenModule::EmitGlobalDefinition(clang::GlobalDecl, llvm::GlobalValue*) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:3638:14
    #37 0xaaaaea759064 in clang::CodeGen::CodeGenModule::EmitDeferred() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:2808:5
    #38 0xaaaaea7590dc in clang::CodeGen::CodeGenModule::EmitDeferred() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:2814:7
    #39 0xaaaaea7590dc in clang::CodeGen::CodeGenModule::EmitDeferred() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:2814:7
    #40 0xaaaaea7590dc in clang::CodeGen::CodeGenModule::EmitDeferred() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:2814:7
    #41 0xaaaaea7590dc in clang::CodeGen::CodeGenModule::EmitDeferred() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:2814:7
    #42 0xaaaaea7590dc in clang::CodeGen::CodeGenModule::EmitDeferred() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:2814:7
    #43 0xaaaaea7590dc in clang::CodeGen::CodeGenModule::EmitDeferred() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:2814:7
    #44 0xaaaaea7590dc in clang::CodeGen::CodeGenModule::EmitDeferred() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:2814:7
    #45 0xaaaaea7590dc in clang::CodeGen::CodeGenModule::EmitDeferred() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:2814:7
    #46 0xaaaaea7590dc in clang::CodeGen::CodeGenModule::EmitDeferred() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:2814:7
    #47 0xaaaaea751844 in clang::CodeGen::CodeGenModule::Release() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenModule.cpp:515:3
    #48 0xaaaaec54f928 in (anonymous namespace)::CodeGeneratorImpl::HandleTranslationUnit(clang::ASTContext&) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/ModuleBuilder.cpp:287:18
    #49 0xaaaaec545b40 in clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/CodeGen/CodeGenAction.cpp:308:14
    #50 0xaaaaf0528bb4 in clang::ParseAST(clang::Sema&, bool, bool) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseAST.cpp:196:13
    #51 0xaaaaec265424 in clang::FrontendAction::Execute() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/Frontend/FrontendAction.cpp:1058:8
    #52 0xaaaaec0b940c in clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/Frontend/CompilerInstance.cpp:1046:33
    #53 0xaaaaec52f63c in clang::ExecuteCompilerInvocation(clang::CompilerInstance*) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:264:25
    #54 0xaaaae2356ecc in cc1_main(llvm::ArrayRef<char const*>, char const*, void*) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/tools/driver/cc1_main.cpp:251:15
    #55 0xaaaae23486dc in ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/tools/driver/driver.cpp:360:12
    #56 0xaaaaebcb7740 in operator() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/Driver/Job.cpp:428:34
    #57 0xaaaaebcb7740 in void llvm::function_ref<void ()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<std::__1::optional<llvm::StringRef>>, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>*, bool*) const::$_0>(long) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/llvm/include/llvm/ADT/STLFunctionalExtras.h:45:12
    #58 0xaaaae9ad4730 in operator() /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/llvm/include/llvm/ADT/STLFunctionalExtras.h:68:12
    #59 0xaaaae9ad4730 in llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/llvm/lib/Support/CrashRecoveryContext.cpp:426:3
    #60 0xaaaaebcb51ac in clang::driver::CC1Command::Execute(llvm::ArrayRef<std::__1::optional<llvm::StringRef>>, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>*, bool*) const /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/Driver/Job.cpp:428:12
    #61 0xaaaaebbf7d68 in clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/Driver/Compilation.cpp:199:15
    #62 0xaaaaebbf8a60 in clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::__1::pair<int, clang::driver::Command const*>>&, bool) const /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/Driver/Compilation.cpp:253:19
    #63 0xaaaaebc4edcc in clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::__1::pair<int, clang::driver::Command const*>>&) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/Driver/Driver.cpp:1853:5
    #64 0xaaaae234449c in clang_main(int, char**) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/tools/driver/driver.cpp:562:21
    #65 0xffff861a73f8  (/lib/aarch64-linux-gnu/libc.so.6+0x273f8) (BuildId: f37f3aa07c797e333fd106472898d361f71798f5)
    #66 0xffff861a74c8 in __libc_start_main (/lib/aarch64-linux-gnu/libc.so.6+0x274c8) (BuildId: f37f3aa07c797e333fd106472898d361f71798f5)
    #67 0xaaaae22b4a2c in _start (/b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm_build_msan_track_origins/bin/clang-17+0x5934a2c)
  Uninitialized value was created by an allocation of 'Mangler' in the stack frame
    #0 0xaaaaf3840e88 in (anonymous namespace)::ItaniumMangleContextImpl::mangleCXXRTTIName(clang::QualType, llvm::raw_ostream&, bool) /b/sanitizer-aarch64-linux-bootstrap-msan/build/llvm-project/clang/lib/AST/ItaniumMangle.cpp:6624:3

[rcvalle]

Fixed use of uninitialized value

[rcvalle]

Fixed initialization order warning

[samitolvanen]

Thanks for fixing the MSan issue, Ramon. There's still a clang-format error that trips the Debian build above, but it's trivial so I can fix it when relanding the patch.

clang/docs/ControlFlowIntegrity.rst

 Specifically, pointers in return and argument types are treated as equivalent as
 long as the qualifiers for the type they point to match. For example, ``char*``,
 ``char**``, and ``int*`` are considered equivalent types. However, ``char*`` and
 ``const char*`` are considered separate types.
 
 ``-fsanitize-cfi-icall-generalize-pointers`` is not compatible with
 ``-fsanitize-cfi-cross-dso``.
 
+.. _cfi-icall-experimental-normalize-integers:
+
+``-fsanitize-cfi-icall-experimental-normalize-integers``
+--------------------------------------------------------
+
+This option enables normalizing integer types as vendor extended types for
+cross-language LLVM CFI/KCFI support with other languages that can't represent
+and encode C/C++ integer types.
+
+Specifically, integer types are encoded as their defined representations (e.g.,
+8-bit signed integer, 16-bit signed integer, 32-bit signed integer, ...) for
+compatibility with languages that define explicitly-sized integer types (e.g.,
+i8, i16, i32, ..., in Rust).
+
+``-fsanitize-cfi-icall-experimental-normalize-integers`` is compatible with
+``-fsanitize-cfi-icall-generalize-pointers``.
+
+This option is currently experimental.
+
 .. _cfi-canonical-jump-tables:
 
 ``-fsanitize-cfi-canonical-jump-tables``
 ----------------------------------------
 
 The default behavior of Clang's indirect function call checker will replace
 the address of each CFI-checked function in the output file's symbol table
 with the address of a jump table entry which will pass CFI checks. We refer

clang/docs/UsersManual.rst

.. option:: -fsanitize-cfi-cross-dso
    of cross-DSO virtual and indirect calls.
 
 .. option:: -fsanitize-cfi-icall-generalize-pointers
 
    Generalize pointers in return and argument types in function type signatures
    checked by Control Flow Integrity indirect call checking. See
    :doc:`ControlFlowIntegrity` for more details.
 
+.. option:: -fsanitize-cfi-icall-experimental-normalize-integers
+
+   Normalize integers in return and argument types in function type signatures
+   checked by Control Flow Integrity indirect call checking. See
+   :doc:`ControlFlowIntegrity` for more details.
+
+   This option is currently experimental.
+
 .. option:: -fstrict-vtable-pointers
 
    Enable optimizations based on the strict rules for overwriting polymorphic
    C++ objects, i.e. the vptr is invariant during an object's lifetime.
    This enables better devirtualization. Turned off by default, because it is
    still experimental.
 
 .. option:: -fwhole-program-vtables

clang/include/clang/AST/Mangle.h

virtual void mangleThunk(const CXXMethodDecl *MD,
                           raw_ostream &) = 0;
   virtual void mangleCXXDtorThunk(const CXXDestructorDecl *DD, CXXDtorType Type,
                                   const ThisAdjustment &ThisAdjustment,
                                   raw_ostream &) = 0;
   virtual void mangleReferenceTemporary(const VarDecl *D,
                                         unsigned ManglingNumber,
                                         raw_ostream &) = 0;
   virtual void mangleCXXRTTI(QualType T, raw_ostream &) = 0;
-  virtual void mangleCXXRTTIName(QualType T, raw_ostream &) = 0;
+  virtual void mangleCXXRTTIName(QualType T, raw_ostream &,
+                                 bool NormalizeIntegers = false) = 0;
   virtual void mangleStringLiteral(const StringLiteral *SL, raw_ostream &) = 0;
   virtual void mangleMSGuidDecl(const MSGuidDecl *GD, raw_ostream&);
 
   void mangleGlobalBlock(const BlockDecl *BD,
                          const NamedDecl *ID,
                          raw_ostream &Out);
   void mangleCtorBlock(const CXXConstructorDecl *CD, CXXCtorType CT,
                        const BlockDecl *BD, raw_ostream &Out);
public:
 
   virtual void mangleSEHFinallyBlock(GlobalDecl EnclosingDecl,
                                      raw_ostream &Out) = 0;
 
   /// Generates a unique string for an externally visible type for use with TBAA
   /// or type uniquing.
   /// TODO: Extend this to internal types by generating names that are unique
   /// across translation units so it can be used with LTO.
-  virtual void mangleTypeName(QualType T, raw_ostream &) = 0;
+  virtual void mangleTypeName(QualType T, raw_ostream &,
+                              bool NormalizeIntegers = false) = 0;
 
   /// @}
 };
 
 class ItaniumMangleContext : public MangleContext {
 public:
   using DiscriminatorOverrideTy =
       llvm::Optional<unsigned> (*)(ASTContext &, const NamedDecl *);

clang/include/clang/Basic/CodeGenOptions.def

CODEGENOPT(SanitizeMemoryParamRetval, 1, 0) ///< Enable detection of uninitialized
                                             ///< in MemorySanitizer
 CODEGENOPT(SanitizeMemoryUseAfterDtor, 1, 0) ///< Enable use-after-delete detection
                                              ///< in MemorySanitizer
 CODEGENOPT(SanitizeCfiCrossDso, 1, 0) ///< Enable cross-dso support in CFI.
 CODEGENOPT(SanitizeMinimalRuntime, 1, 0) ///< Use "_minimal" sanitizer runtime for
                                          ///< diagnostics.
 CODEGENOPT(SanitizeCfiICallGeneralizePointers, 1, 0) ///< Generalize pointer types in
                                                      ///< CFI icall function signatures
+CODEGENOPT(SanitizeCfiICallNormalizeIntegers, 1, 0) ///< Normalize integer types in
+                                                    ///< CFI icall function signatures
 CODEGENOPT(SanitizeCfiCanonicalJumpTables, 1, 0) ///< Make jump table symbols canonical
                                                  ///< instead of creating a local jump table.
 CODEGENOPT(SanitizeCoverageType, 2, 0) ///< Type of sanitizer coverage
                                        ///< instrumentation.
 CODEGENOPT(SanitizeCoverageIndirectCalls, 1, 0) ///< Enable sanitizer coverage
                                                 ///< for indirect calls.
 CODEGENOPT(SanitizeCoverageTraceBB, 1, 0) ///< Enable basic block tracing in
                                           ///< in sanitizer coverage.

clang/include/clang/Driver/Options.td

defm sanitize_cfi_cross_dso : BoolOption<"f", "sanitize-cfi-cross-dso",
   CodeGenOpts<"SanitizeCfiCrossDso">, DefaultFalse,
   PosFlag<SetTrue, [], "Enable">, NegFlag<SetFalse, [CoreOption, NoXarchOption], "Disable">,
   BothFlags<[], " control flow integrity (CFI) checks for cross-DSO calls.">>,
   Group<f_clang_Group>;
 def fsanitize_cfi_icall_generalize_pointers : Flag<["-"], "fsanitize-cfi-icall-generalize-pointers">,
                                               Group<f_clang_Group>,
                                               HelpText<"Generalize pointers in CFI indirect call type signature checks">,
                                               MarshallingInfoFlag<CodeGenOpts<"SanitizeCfiICallGeneralizePointers">>;
+def fsanitize_cfi_icall_normalize_integers : Flag<["-"], "fsanitize-cfi-icall-experimental-normalize-integers">,
+                                             Group<f_clang_Group>,
+                                             HelpText<"Normalize integers in CFI indirect call type signature checks">,
+                                             MarshallingInfoFlag<CodeGenOpts<"SanitizeCfiICallNormalizeIntegers">>;
 defm sanitize_cfi_canonical_jump_tables : BoolOption<"f", "sanitize-cfi-canonical-jump-tables",
   CodeGenOpts<"SanitizeCfiCanonicalJumpTables">, DefaultFalse,
   PosFlag<SetTrue, [], "Make">, NegFlag<SetFalse, [CoreOption, NoXarchOption], "Do not make">,
   BothFlags<[], " the jump table addresses canonical in the symbol table">>,
   Group<f_clang_Group>;
 defm sanitize_stats : BoolOption<"f", "sanitize-stats",
   CodeGenOpts<"SanitizeStats">, DefaultFalse,
   PosFlag<SetTrue, [], "Enable">, NegFlag<SetFalse, [CoreOption, NoXarchOption], "Disable">,

clang/include/clang/Driver/SanitizerArgs.h

class SanitizerArgs {
   std::vector<std::string> CoverageIgnorelistFiles;
   int CoverageFeatures = 0;
   int BinaryMetadataFeatures = 0;
   int MsanTrackOrigins = 0;
   bool MsanUseAfterDtor = true;
   bool MsanParamRetval = true;
   bool CfiCrossDso = false;
   bool CfiICallGeneralizePointers = false;
+  bool CfiICallNormalizeIntegers = false;
   bool CfiCanonicalJumpTables = false;
   int AsanFieldPadding = 0;
   bool SharedRuntime = false;
   bool AsanUseAfterScope = true;
   bool AsanPoisonCustomArrayCookie = false;
   bool AsanGlobalsDeadStripping = false;
   bool AsanUseOdrIndicator = false;
   bool AsanInvalidPointerCmp = false;

clang/lib/AST/ItaniumMangle.cpp

void mangleCXXDtorThunk(const CXXDestructorDecl *DD, CXXDtorType Type,
                           raw_ostream &) override;
   void mangleReferenceTemporary(const VarDecl *D, unsigned ManglingNumber,
                                 raw_ostream &) override;
   void mangleCXXVTable(const CXXRecordDecl *RD, raw_ostream &) override;
   void mangleCXXVTT(const CXXRecordDecl *RD, raw_ostream &) override;
   void mangleCXXCtorVTable(const CXXRecordDecl *RD, int64_t Offset,
                            const CXXRecordDecl *Type, raw_ostream &) override;
   void mangleCXXRTTI(QualType T, raw_ostream &) override;
-  void mangleCXXRTTIName(QualType T, raw_ostream &) override;
-  void mangleTypeName(QualType T, raw_ostream &) override;
+  void mangleCXXRTTIName(QualType T, raw_ostream &,
+                         bool NormalizeIntegers) override;
+  void mangleTypeName(QualType T, raw_ostream &,
+                      bool NormalizeIntegers) override;
 
   void mangleCXXCtorComdat(const CXXConstructorDecl *D, raw_ostream &) override;
   void mangleCXXDtorComdat(const CXXDestructorDecl *D, raw_ostream &) override;
   void mangleStaticGuardVariable(const VarDecl *D, raw_ostream &) override;
   void mangleDynamicInitializer(const VarDecl *D, raw_ostream &Out) override;
   void mangleDynamicAtExitDestructor(const VarDecl *D,
                                      raw_ostream &Out) override;
   void mangleDynamicStermFinalizer(const VarDecl *D, raw_ostream &Out) override;
public:
 
   /// @}
 };
 
 /// Manage the mangling of a single name.
 class CXXNameMangler {
   ItaniumMangleContextImpl &Context;
   raw_ostream &Out;
+  /// Normalize integer types for cross-language CFI support with other
+  /// languages that can't represent and encode C/C++ integer types.
+  bool NormalizeIntegers = false;
+
   bool NullOut = false;
   /// In the "DisableDerivedAbiTags" mode derived ABI tags are not calculated.
   /// This mode is used when mangler creates another mangler recursively to
   /// calculate ABI tags for the function return value or the variable type.
   /// Also it is required to avoid infinite recursion in some cases.
   bool DisableDerivedAbiTags = false;
 
   /// The "structor" is the top-level declaration being mangled, if
CXXNameMangler(ItaniumMangleContextImpl &C, raw_ostream &Out_,
                  const CXXConstructorDecl *D, CXXCtorType Type)
       : Context(C), Out(Out_), Structor(getStructor(D)), StructorType(Type),
         AbiTagsRoot(AbiTags) {}
   CXXNameMangler(ItaniumMangleContextImpl &C, raw_ostream &Out_,
                  const CXXDestructorDecl *D, CXXDtorType Type)
       : Context(C), Out(Out_), Structor(getStructor(D)), StructorType(Type),
         AbiTagsRoot(AbiTags) {}
 
+  CXXNameMangler(ItaniumMangleContextImpl &C, raw_ostream &Out_,
+                 bool NormalizeIntegers_)
+      : Context(C), Out(Out_), NormalizeIntegers(NormalizeIntegers_),
+        NullOut(false), AbiTagsRoot(AbiTags) {}
   CXXNameMangler(CXXNameMangler &Outer, raw_ostream &Out_)
       : Context(Outer.Context), Out(Out_), Structor(Outer.Structor),
         StructorType(Outer.StructorType), SeqID(Outer.SeqID),
         FunctionTypeDepth(Outer.FunctionTypeDepth), AbiTagsRoot(AbiTags),
         Substitutions(Outer.Substitutions),
         ModuleSubstitutions(Outer.ModuleSubstitutions) {}
 
   CXXNameMangler(CXXNameMangler &Outer, llvm::raw_null_ostream &Out_)
void CXXNameMangler::mangleType(const BuiltinType *T) {
   // UNSUPPORTED:    ::= Df # IEEE 754r decimal floating point (32 bits)
   //                 ::= Dh # IEEE 754r half-precision floating point (16 bits)
   //                 ::= DF <number> _ # ISO/IEC TS 18661 binary floating point type _FloatN (N bits);
   //                 ::= Di # char32_t
   //                 ::= Ds # char16_t
   //                 ::= Dn # std::nullptr_t (i.e., decltype(nullptr))
   //                 ::= u <source-name>    # vendor extended type
   std::string type_name;
+  // Normalize integer types as vendor extended types:
+  // u<length>i<type size>
+  // u<length>u<type size>
+  if (NormalizeIntegers && T->isInteger()) {
+    if (T->isSignedInteger()) {
+      switch (getASTContext().getTypeSize(T)) {
+      case 8:
+        // Pick a representative for each integer size in the substitution
+        // dictionary. (Its actual defined size is not relevant.)
+        if (mangleSubstitution(BuiltinType::SChar))
+          break;
+        Out << "u2i8";
+        addSubstitution(BuiltinType::SChar);
+        break;
+      case 16:
+        if (mangleSubstitution(BuiltinType::Short))
+          break;
+        Out << "u3i16";
+        addSubstitution(BuiltinType::Short);
+        break;
+      case 32:
+        if (mangleSubstitution(BuiltinType::Int))
+          break;
+        Out << "u3i32";
+        addSubstitution(BuiltinType::Int);
+        break;
+      case 64:
+        if (mangleSubstitution(BuiltinType::Long))
+          break;
+        Out << "u3i64";
+        addSubstitution(BuiltinType::Long);
+        break;
+      case 128:
+        if (mangleSubstitution(BuiltinType::Int128))
+          break;
+        Out << "u4i128";
+        addSubstitution(BuiltinType::Int128);
+        break;
+      default:
+        llvm_unreachable("Unknown integer size for normalization");
+      }
+    } else {
+      switch (getASTContext().getTypeSize(T)) {
+      case 8:
+        if (mangleSubstitution(BuiltinType::UChar))
+          break;
+        Out << "u2u8";
+        addSubstitution(BuiltinType::UChar);
+        break;
+      case 16:
+        if (mangleSubstitution(BuiltinType::UShort))
+          break;
+        Out << "u3u16";
+        addSubstitution(BuiltinType::UShort);
+        break;
+      case 32:
+        if (mangleSubstitution(BuiltinType::UInt))
+          break;
+        Out << "u3u32";
+        addSubstitution(BuiltinType::UInt);
+        break;
+      case 64:
+        if (mangleSubstitution(BuiltinType::ULong))
+          break;
+        Out << "u3u64";
+        addSubstitution(BuiltinType::ULong);
+        break;
+      case 128:
+        if (mangleSubstitution(BuiltinType::UInt128))
+          break;
+        Out << "u4u128";
+        addSubstitution(BuiltinType::UInt128);
+        break;
+      default:
+        llvm_unreachable("Unknown integer size for normalization");
+      }
+    }
+    return;
+  }
   switch (T->getKind()) {
   case BuiltinType::Void:
     Out << 'v';
     break;
   case BuiltinType::Bool:
     Out << 'b';
     break;
   case BuiltinType::Char_U:

 void ItaniumMangleContextImpl::mangleCXXRTTI(QualType Ty, raw_ostream &Out) {
   // <special-name> ::= TI <type>  # typeinfo structure
   assert(!Ty.hasQualifiers() && "RTTI info cannot have top-level qualifiers");
   CXXNameMangler Mangler(*this, Out);
   Mangler.getStream() << "_ZTI";
   Mangler.mangleType(Ty);
 }
 
-void ItaniumMangleContextImpl::mangleCXXRTTIName(QualType Ty,
-                                                 raw_ostream &Out) {
+void ItaniumMangleContextImpl::mangleCXXRTTIName(
+    QualType Ty, raw_ostream &Out, bool NormalizeIntegers = false) {
   // <special-name> ::= TS <type>  # typeinfo name (null terminated byte string)
-  CXXNameMangler Mangler(*this, Out);
+  CXXNameMangler Mangler(*this, Out, NormalizeIntegers);
   Mangler.getStream() << "_ZTS";
   Mangler.mangleType(Ty);
 }
 
-void ItaniumMangleContextImpl::mangleTypeName(QualType Ty, raw_ostream &Out) {
-  mangleCXXRTTIName(Ty, Out);
+void ItaniumMangleContextImpl::mangleTypeName(QualType Ty, raw_ostream &Out,
+                                              bool NormalizeIntegers = false) {
+  mangleCXXRTTIName(Ty, Out, NormalizeIntegers);
 }
 
 void ItaniumMangleContextImpl::mangleStringLiteral(const StringLiteral *, raw_ostream &) {
   llvm_unreachable("Can't mangle string literals");
 }
 
 void ItaniumMangleContextImpl::mangleLambdaSig(const CXXRecordDecl *Lambda,
                                                raw_ostream &Out) {

clang/lib/AST/MicrosoftMangle.cpp

void mangleCXXThrowInfo(QualType T, bool IsConst, bool IsVolatile,
                           raw_ostream &Out) override;
   void mangleCXXCatchableTypeArray(QualType T, uint32_t NumEntries,
                                    raw_ostream &Out) override;
   void mangleCXXCatchableType(QualType T, const CXXConstructorDecl *CD,
                               CXXCtorType CT, uint32_t Size, uint32_t NVOffset,
                               int32_t VBPtrOffset, uint32_t VBIndex,
                               raw_ostream &Out) override;
   void mangleCXXRTTI(QualType T, raw_ostream &Out) override;
-  void mangleCXXRTTIName(QualType T, raw_ostream &Out) override;
+  void mangleCXXRTTIName(QualType T, raw_ostream &Out,
+                         bool NormalizeIntegers) override;
   void mangleCXXRTTIBaseClassDescriptor(const CXXRecordDecl *Derived,
                                         uint32_t NVOffset, int32_t VBPtrOffset,
                                         uint32_t VBTableOffset, uint32_t Flags,
                                         raw_ostream &Out) override;
   void mangleCXXRTTIBaseClassArray(const CXXRecordDecl *Derived,
                                    raw_ostream &Out) override;
   void mangleCXXRTTIClassHierarchyDescriptor(const CXXRecordDecl *Derived,
                                              raw_ostream &Out) override;
   void
   mangleCXXRTTICompleteObjectLocator(const CXXRecordDecl *Derived,
                                      ArrayRef<const CXXRecordDecl *> BasePath,
                                      raw_ostream &Out) override;
-  void mangleTypeName(QualType T, raw_ostream &) override;
+  void mangleTypeName(QualType T, raw_ostream &,
+                      bool NormalizeIntegers) override;
   void mangleReferenceTemporary(const VarDecl *, unsigned ManglingNumber,
                                 raw_ostream &) override;
   void mangleStaticGuardVariable(const VarDecl *D, raw_ostream &Out) override;
   void mangleThreadSafeStaticGuardVariable(const VarDecl *D, unsigned GuardNum,
                                            raw_ostream &Out) override;
   void mangleDynamicInitializer(const VarDecl *D, raw_ostream &Out) override;
   void mangleDynamicAtExitDestructor(const VarDecl *D,
                                      raw_ostream &Out) override;

 void MicrosoftMangleContextImpl::mangleCXXRTTI(QualType T, raw_ostream &Out) {
   msvc_hashing_ostream MHO(Out);
   MicrosoftCXXNameMangler Mangler(*this, MHO);
   Mangler.getStream() << "??_R0";
   Mangler.mangleType(T, SourceRange(), MicrosoftCXXNameMangler::QMM_Result);
   Mangler.getStream() << "@8";
 }
 
-void MicrosoftMangleContextImpl::mangleCXXRTTIName(QualType T,
-                                                   raw_ostream &Out) {
+void MicrosoftMangleContextImpl::mangleCXXRTTIName(
+    QualType T, raw_ostream &Out, bool NormalizeIntegers = false) {
   MicrosoftCXXNameMangler Mangler(*this, Out);
   Mangler.getStream() << '.';
   Mangler.mangleType(T, SourceRange(), MicrosoftCXXNameMangler::QMM_Result);
 }
 
 void MicrosoftMangleContextImpl::mangleCXXVirtualDisplacementMap(
     const CXXRecordDecl *SrcRD, const CXXRecordDecl *DstRD, raw_ostream &Out) {
   msvc_hashing_ostream MHO(Out);
void MicrosoftMangleContextImpl::mangleSEHFinallyBlock(
   // The function body is in the same comdat as the function with the handler,
   // so the numbering here doesn't have to be the same across TUs.
   //
   // <mangled-name> ::= ?fin$ <filter-number> @0
   Mangler.getStream() << "?fin$" << SEHFinallyIds[EnclosingDecl]++ << "@0@";
   Mangler.mangleName(EnclosingDecl);
 }
 
-void MicrosoftMangleContextImpl::mangleTypeName(QualType T, raw_ostream &Out) {
+void MicrosoftMangleContextImpl::mangleTypeName(
+    QualType T, raw_ostream &Out, bool NormalizeIntegers = false) {
   // This is just a made up unique string for the purposes of tbaa.  undname
   // does *not* know how to demangle it.
   MicrosoftCXXNameMangler Mangler(*this, Out);
   Mangler.getStream() << '?';
   Mangler.mangleType(T, SourceRange());
 }
 
 void MicrosoftMangleContextImpl::mangleReferenceTemporary(

clang/lib/CodeGen/CodeGenModule.cpp

 llvm::ConstantInt *CodeGenModule::CreateKCFITypeId(QualType T) {
   if (auto *FnType = T->getAs<FunctionProtoType>())
     T = getContext().getFunctionType(
         FnType->getReturnType(), FnType->getParamTypes(),
         FnType->getExtProtoInfo().withExceptionSpec(EST_None));
 
   std::string OutName;
   llvm::raw_string_ostream Out(OutName);
-  getCXXABI().getMangleContext().mangleTypeName(T, Out);
+  getCXXABI().getMangleContext().mangleTypeName(
+      T, Out, !!getCodeGenOpts().SanitizeCfiICallNormalizeIntegers);
+
+  if (getCodeGenOpts().SanitizeCfiICallNormalizeIntegers)
+    Out << ".normalized";
 
   return llvm::ConstantInt::get(Int32Ty,
                                 static_cast<uint32_t>(llvm::xxHash64(OutName)));
 }
 
 void CodeGenModule::SetLLVMFunctionAttributes(GlobalDecl GD,
                                               const CGFunctionInfo &Info,
                                               llvm::Function *F, bool IsThunk) {
CodeGenModule::CreateMetadataIdentifierImpl(QualType T, MetadataTypeMap &Map,
 
   llvm::Metadata *&InternalId = Map[T.getCanonicalType()];
   if (InternalId)
     return InternalId;
 
   if (isExternallyVisible(T->getLinkage())) {
     std::string OutName;
     llvm::raw_string_ostream Out(OutName);
-    getCXXABI().getMangleContext().mangleTypeName(T, Out);
+    getCXXABI().getMangleContext().mangleTypeName(
+        T, Out, !!getCodeGenOpts().SanitizeCfiICallNormalizeIntegers);
+
+    if (getCodeGenOpts().SanitizeCfiICallNormalizeIntegers)
+      Out << ".normalized";
+
     Out << Suffix;
 
     InternalId = llvm::MDString::get(getLLVMContext(), Out.str());
   } else {
     InternalId = llvm::MDNode::getDistinct(getLLVMContext(),
                                            llvm::ArrayRef<llvm::Metadata *>());
   }
 

clang/lib/Driver/SanitizerArgs.cpp

SanitizerArgs::SanitizerArgs(const ToolChain &TC,
 
   if (AllAddedKinds & SanitizerKind::CFI) {
     // Without PIE, external function address may resolve to a PLT record, which
     // can not be verified by the target module.
     NeedPIE |= CfiCrossDso;
     CfiICallGeneralizePointers =
         Args.hasArg(options::OPT_fsanitize_cfi_icall_generalize_pointers);
 
+    CfiICallNormalizeIntegers =
+        Args.hasArg(options::OPT_fsanitize_cfi_icall_normalize_integers);
+
     if (CfiCrossDso && CfiICallGeneralizePointers && DiagnoseErrors)
       D.Diag(diag::err_drv_argument_not_allowed_with)
           << "-fsanitize-cfi-cross-dso"
           << "-fsanitize-cfi-icall-generalize-pointers";
 
     CfiCanonicalJumpTables =
         Args.hasFlag(options::OPT_fsanitize_cfi_canonical_jump_tables,
                      options::OPT_fno_sanitize_cfi_canonical_jump_tables, true);
void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
   }
 
   if (CfiCrossDso)
     CmdArgs.push_back("-fsanitize-cfi-cross-dso");
 
   if (CfiICallGeneralizePointers)
     CmdArgs.push_back("-fsanitize-cfi-icall-generalize-pointers");
 
+  if (CfiICallNormalizeIntegers)
+    CmdArgs.push_back("-fsanitize-cfi-icall-experimental-normalize-integers");
+
   if (CfiCanonicalJumpTables)
     CmdArgs.push_back("-fsanitize-cfi-canonical-jump-tables");
 
   if (Stats)
     CmdArgs.push_back("-fsanitize-stats");
 
   if (MinimalRuntime)
     CmdArgs.push_back("-fsanitize-minimal-runtime");

clang/test/CodeGen/cfi-icall-normalize.c

+// RUN: %clang_cc1 -triple x86_64-unknown-linux -fsanitize=cfi-icall -fsanitize-trap=cfi-icall -fsanitize-cfi-icall-experimental-normalize-integers -emit-llvm -o - %s | FileCheck %s
+
+// Test that integer types are normalized for cross-language CFI support with
+// other languages that can't represent and encode C/C++ integer types.
+
+void foo0(char arg) { }
+// CHECK: define{{.*}}foo0{{.*}}!type ![[TYPE0:[0-9]+]] !type !{{[0-9]+}}
+void foo1(char arg1, signed char arg2) { }
+// CHECK: define{{.*}}foo1{{.*}}!type ![[TYPE1:[0-9]+]] !type !{{[0-9]+}}
+void foo2(char arg1, signed char arg2, signed char arg3) { }
+// CHECK: define{{.*}}foo2{{.*}}!type ![[TYPE2:[0-9]+]] !type !{{[0-9]+}}
+void foo3(int arg) { }
+// CHECK: define{{.*}}foo3{{.*}}!type ![[TYPE3:[0-9]+]] !type !{{[0-9]+}}
+void foo4(int arg1, int arg2) { }
+// CHECK: define{{.*}}foo4{{.*}}!type ![[TYPE4:[0-9]+]] !type !{{[0-9]+}}
+void foo5(int arg1, int arg2, int arg3) { }
+// CHECK: define{{.*}}foo5{{.*}}!type ![[TYPE5:[0-9]+]] !type !{{[0-9]+}}
+void foo6(long arg) { }
+// CHECK: define{{.*}}foo6{{.*}}!type ![[TYPE6:[0-9]+]] !type !{{[0-9]+}}
+void foo7(long arg1, long long arg2) { }
+// CHECK: define{{.*}}foo7{{.*}}!type ![[TYPE7:[0-9]+]] !type !{{[0-9]+}}
+void foo8(long arg1, long long arg2, long long arg3) { }
+// CHECK: define{{.*}}foo8{{.*}}!type ![[TYPE8:[0-9]+]] !type !{{[0-9]+}}
+void foo9(short arg) { }
+// CHECK: define{{.*}}foo9{{.*}}!type ![[TYPE9:[0-9]+]] !type !{{[0-9]+}}
+void foo10(short arg1, short arg2) { }
+// CHECK: define{{.*}}foo10{{.*}}!type ![[TYPE10:[0-9]+]] !type !{{[0-9]+}}
+void foo11(short arg1, short arg2, short arg3) { }
+// CHECK: define{{.*}}foo11{{.*}}!type ![[TYPE11:[0-9]+]] !type !{{[0-9]+}}
+void foo12(unsigned char arg) { }
+// CHECK: define{{.*}}foo12{{.*}}!type ![[TYPE12:[0-9]+]] !type !{{[0-9]+}}
+void foo13(unsigned char arg1, unsigned char arg2) { }
+// CHECK: define{{.*}}foo13{{.*}}!type ![[TYPE13:[0-9]+]] !type !{{[0-9]+}}
+void foo14(unsigned char arg1, unsigned char arg2, unsigned char arg3) { }
+// CHECK: define{{.*}}foo14{{.*}}!type ![[TYPE14:[0-9]+]] !type !{{[0-9]+}}
+void foo15(unsigned int arg) { }
+// CHECK: define{{.*}}foo15{{.*}}!type ![[TYPE15:[0-9]+]] !type !{{[0-9]+}}
+void foo16(unsigned int arg1, unsigned int arg2) { }
+// CHECK: define{{.*}}foo16{{.*}}!type ![[TYPE16:[0-9]+]] !type !{{[0-9]+}}
+void foo17(unsigned int arg1, unsigned int arg2, unsigned int arg3) { }
+// CHECK: define{{.*}}foo17{{.*}}!type ![[TYPE17:[0-9]+]] !type !{{[0-9]+}}
+void foo18(unsigned long arg) { }
+// CHECK: define{{.*}}foo18{{.*}}!type ![[TYPE18:[0-9]+]] !type !{{[0-9]+}}
+void foo19(unsigned long arg1, unsigned long long arg2) { }
+// CHECK: define{{.*}}foo19{{.*}}!type ![[TYPE19:[0-9]+]] !type !{{[0-9]+}}
+void foo20(unsigned long arg1, unsigned long long arg2, unsigned long long arg3) { }
+// CHECK: define{{.*}}foo20{{.*}}!type ![[TYPE20:[0-9]+]] !type !{{[0-9]+}}
+void foo21(unsigned short arg) { }
+// CHECK: define{{.*}}foo21{{.*}}!type ![[TYPE21:[0-9]+]] !type !{{[0-9]+}}
+void foo22(unsigned short arg1, unsigned short arg2) { }
+// CHECK: define{{.*}}foo22{{.*}}!type ![[TYPE22:[0-9]+]] !type !{{[0-9]+}}
+void foo23(unsigned short arg1, unsigned short arg2, unsigned short arg3) { }
+// CHECK: define{{.*}}foo23{{.*}}!type ![[TYPE23:[0-9]+]] !type !{{[0-9]+}}
+
+// CHECK: ![[TYPE0]] = !{i64 0, !"_ZTSFv{{u2i8|u2u8}}E.normalized"}
+// CHECK: ![[TYPE1]] = !{i64 0, !"_ZTSFv{{u2i8S_|u2u8u2i8}}E.normalized"}
+// CHECK: ![[TYPE2]] = !{i64 0, !"_ZTSFv{{u2i8S_S_|u2u8u2i8S0_}}E.normalized"}
+// CHECK: ![[TYPE3]] = !{i64 0, !"_ZTSFv{{u3i16|u3i32|u3i64}}E.normalized"}
+// CHECK: ![[TYPE4]] = !{i64 0, !"_ZTSFv{{u3i16|u3i32|u3i64}}S_E.normalized"}
+// CHECK: ![[TYPE5]] = !{i64 0, !"_ZTSFv{{u3i16|u3i32|u3i64}}S_S_E.normalized"}
+// CHECK: ![[TYPE6]] = !{i64 0, !"_ZTSFv{{u3i32|u3i64}}E.normalized"}
+// CHECK: ![[TYPE7]] = !{i64 0, !"_ZTSFv{{u3i32u3i64|u3i64S_}}E.normalized"}
+// CHECK: ![[TYPE8]] = !{i64 0, !"_ZTSFv{{u3i32u3i64S0_|u3i64S_S_}}E.normalized"}
+// CHECK: ![[TYPE9]] = !{i64 0, !"_ZTSFvu3i16E.normalized"}
+// CHECK: ![[TYPE10]] = !{i64 0, !"_ZTSFvu3i16S_E.normalized"}
+// CHECK: ![[TYPE11]] = !{i64 0, !"_ZTSFvu3i16S_S_E.normalized"}
+// CHECK: ![[TYPE12]] = !{i64 0, !"_ZTSFvu2u8E.normalized"}
+// CHECK: ![[TYPE13]] = !{i64 0, !"_ZTSFvu2u8S_E.normalized"}
+// CHECK: ![[TYPE14]] = !{i64 0, !"_ZTSFvu2u8S_S_E.normalized"}
+// CHECK: ![[TYPE15]] = !{i64 0, !"_ZTSFv{{u3u16|u3u32|u3u64}}E.normalized"}
+// CHECK: ![[TYPE16]] = !{i64 0, !"_ZTSFv{{u3u16|u3u32|u3u64}}S_E.normalized"}
+// CHECK: ![[TYPE17]] = !{i64 0, !"_ZTSFv{{u3u16|u3u32|u3u64}}S_S_E.normalized"}
+// CHECK: ![[TYPE18]] = !{i64 0, !"_ZTSFv{{u3u32|u3u64}}E.normalized"}
+// CHECK: ![[TYPE19]] = !{i64 0, !"_ZTSFv{{u3u32u3u64|u3u64S_}}E.normalized"}
+// CHECK: ![[TYPE20]] = !{i64 0, !"_ZTSFv{{u3u32u3u64S0_|u3u64S_S_}}E.normalized"}
+// CHECK: ![[TYPE21]] = !{i64 0, !"_ZTSFvu3u16E.normalized"}
+// CHECK: ![[TYPE22]] = !{i64 0, !"_ZTSFvu3u16S_E.normalized"}
+// CHECK: ![[TYPE23]] = !{i64 0, !"_ZTSFvu3u16S_S_E.normalized"}

clang/test/CodeGen/cfi-icall-normalize2.c

+// RUN: %clang_cc1 -triple x86_64-unknown-linux -fsanitize=cfi-icall -fsanitize-trap=cfi-icall -fsanitize-cfi-icall-experimental-normalize-integers -emit-llvm -o - %s | FileCheck %s
+
+// Test that normalized type metadata for functions are emitted for cross-language CFI support with
+// other languages that can't represent and encode C/C++ integer types.
+
+void foo(void (*fn)(int), int arg) {
+    // CHECK-LABEL: define{{.*}}foo
+    // CHECK-SAME: {{.*}}!type ![[TYPE1:[0-9]+]] !type !{{[0-9]+}}
+    // CHECK: call i1 @llvm.type.test({{i8\*|ptr}} {{%f|%0}}, metadata !"_ZTSFv{{u3i16|u3i32|u3i64}}E.normalized")
+    fn(arg);
+}
+
+void bar(void (*fn)(int, int), int arg1, int arg2) {
+    // CHECK-LABEL: define{{.*}}bar
+    // CHECK-SAME: {{.*}}!type ![[TYPE2:[0-9]+]] !type !{{[0-9]+}}
+    // CHECK: call i1 @llvm.type.test({{i8\*|ptr}} {{%f|%0}}, metadata !"_ZTSFv{{u3i16|u3i32|u3i64}}S_E.normalized")
+    fn(arg1, arg2);
+}
+
+void baz(void (*fn)(int, int, int), int arg1, int arg2, int arg3) {
+    // CHECK-LABEL: define{{.*}}baz
+    // CHECK-SAME: {{.*}}!type ![[TYPE3:[0-9]+]] !type !{{[0-9]+}}
+    // CHECK: call i1 @llvm.type.test({{i8\*|ptr}} {{%f|%0}}, metadata !"_ZTSFv{{u3i16|u3i32|u3i64}}S_S_E.normalized")
+    fn(arg1, arg2, arg3);
+}
+
+// CHECK: ![[TYPE1]] = !{i64 0, !"_ZTSFvPFv{{u3i16|u3i32|u3i64}}ES_E.normalized"}
+// CHECK: ![[TYPE2]] = !{i64 0, !"_ZTSFvPFv{{u3i16|u3i32|u3i64}}S_ES_S_E.normalized"}
+// CHECK: ![[TYPE3]] = !{i64 0, !"_ZTSFvPFv{{u3i16|u3i32|u3i64}}S_S_ES_S_S_E.normalized"}

clang/test/CodeGen/kcfi-normalize.c

+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-llvm -fsanitize=kcfi -fsanitize-cfi-icall-experimental-normalize-integers -o - %s | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-llvm -fsanitize=kcfi -fsanitize-cfi-icall-experimental-normalize-integers -x c++ -o - %s | FileCheck %s
+#if !__has_feature(kcfi)
+#error Missing kcfi?
+#endif
+
+// Test that normalized type metadata for functions are emitted for cross-language KCFI support with
+// other languages that can't represent and encode C/C++ integer types.
+
+void foo(void (*fn)(int), int arg) {
+    // CHECK-LABEL: define{{.*}}foo
+    // CHECK-SAME: {{.*}}!kcfi_type ![[TYPE1:[0-9]+]]
+    // CHECK: call void %0(i32 noundef %1){{.*}}[ "kcfi"(i32 1162514891) ]
+    fn(arg);
+}
+
+void bar(void (*fn)(int, int), int arg1, int arg2) {
+    // CHECK-LABEL: define{{.*}}bar
+    // CHECK-SAME: {{.*}}!kcfi_type ![[TYPE2:[0-9]+]]
+    // CHECK: call void %0(i32 noundef %1, i32 noundef %2){{.*}}[ "kcfi"(i32 448046469) ]
+    fn(arg1, arg2);
+}
+
+void baz(void (*fn)(int, int, int), int arg1, int arg2, int arg3) {
+    // CHECK-LABEL: define{{.*}}baz
+    // CHECK-SAME: {{.*}}!kcfi_type ![[TYPE3:[0-9]+]]
+    // CHECK: call void %0(i32 noundef %1, i32 noundef %2, i32 noundef %3){{.*}}[ "kcfi"(i32 -2049681433) ]
+    fn(arg1, arg2, arg3);
+}
+
+// CHECK: ![[TYPE1]] = !{i32 -1143117868}
+// CHECK: ![[TYPE2]] = !{i32 -460921415}
+// CHECK: ![[TYPE3]] = !{i32 -333839615}