jobextra/llvm/llvm-coroutines-ubsan.patch
2022-08-07 14:14:55 +03:00

288 lines
12 KiB
Diff

From 1030297d77ae5110b7873530f645aeec3a4264ba Mon Sep 17 00:00:00 2001
From: Yuanfang Chen <yuanfang.chen@sony.com>
Date: Mon, 27 Jun 2022 11:33:45 -0700
Subject: [PATCH 1/2] [ubsan] Using metadata instead of prologue data for
function sanitizer
Information in the function `Prologue Data` is intentionally opaque.
When a function with `Prologue Data` is duplicated. The self (global
value) references inside `Prologue Data` is still pointing to the
original function. This may cause errors like `fatal error: error in backend: Cannot represent a difference across sections`.
This patch detaches the information from function `Prologue Data`
and attaches it to a function metadata node.
This and D116130 fix https://github.com/llvm/llvm-project/issues/49689.
Reviewed By: pcc
Differential Revision: https://reviews.llvm.org/D115844
(cherry picked from commit 6678f8e505b19069a9dbdc3e3ee088d543752412)
---
llvm/docs/LangRef.rst | 22 ++++++++++++++++++-
llvm/include/llvm/IR/FixedMetadataKinds.def | 1 +
llvm/include/llvm/IR/MDBuilder.h | 4 ++++
llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp | 18 +++++++++++++++
llvm/lib/IR/MDBuilder.cpp | 8 +++++++
.../Instrumentation/AddressSanitizer.cpp | 10 ++++-----
llvm/test/CodeGen/X86/func-sanitizer.ll | 18 +++++++++++++++
7 files changed, 75 insertions(+), 6 deletions(-)
create mode 100644 llvm/test/CodeGen/X86/func-sanitizer.ll
diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
index 920834b10897..a5a84a2f297b 100644
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -5194,7 +5194,7 @@ multiple metadata attachments with the same identifier.
A transformation is required to drop any metadata attachment that it does not
know or know it can't preserve. Currently there is an exception for metadata
-attachment to globals for ``!type`` and ``!absolute_symbol`` which can't be
+attachment to globals for ``!func_sanitize``, ``!type`` and ``!absolute_symbol`` which can't be
unconditionally dropped unless the global is itself deleted.
Metadata attached to a module using named metadata may not be dropped, with
@@ -7080,6 +7080,26 @@ Example:
%a.addr = alloca float*, align 8, !annotation !0
!0 = !{!"auto-init"}
+'``func_sanitize``' Metadata
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The ``func_sanitize`` metadata is used to attach two values for the function
+sanitizer instrumentation. The first value is the ubsan function signature.
+The second value is the address of the proxy variable which stores the address
+of the RTTI descriptor. If :ref:`prologue <prologuedata>` and '``func_sanitize``'
+are used at the same time, :ref:`prologue <prologuedata>` is emitted before
+'``func_sanitize``' in the output.
+
+Example:
+
+.. code-block:: text
+
+ @__llvm_rtti_proxy = private unnamed_addr constant i8* bitcast ({ i8*, i8* }* @_ZTIFvvE to i8*)
+ define void @_Z3funv() !func_sanitize !0 {
+ return void
+ }
+ !0 = !{i32 846595819, i8** @__llvm_rtti_proxy}
+
Module Flags Metadata
=====================
diff --git a/llvm/include/llvm/IR/FixedMetadataKinds.def b/llvm/include/llvm/IR/FixedMetadataKinds.def
index 31979cd2f9db..baa7a91cbf56 100644
--- a/llvm/include/llvm/IR/FixedMetadataKinds.def
+++ b/llvm/include/llvm/IR/FixedMetadataKinds.def
@@ -42,3 +42,4 @@ LLVM_FIXED_MD_KIND(MD_preserve_access_index, "llvm.preserve.access.index", 27)
LLVM_FIXED_MD_KIND(MD_vcall_visibility, "vcall_visibility", 28)
LLVM_FIXED_MD_KIND(MD_noundef, "noundef", 29)
LLVM_FIXED_MD_KIND(MD_annotation, "annotation", 30)
+LLVM_FIXED_MD_KIND(MD_func_sanitize, "func_sanitize", 31)
diff --git a/llvm/include/llvm/IR/MDBuilder.h b/llvm/include/llvm/IR/MDBuilder.h
index 42829388b79a..21d7b8b6da71 100644
--- a/llvm/include/llvm/IR/MDBuilder.h
+++ b/llvm/include/llvm/IR/MDBuilder.h
@@ -108,6 +108,10 @@ public:
/// Merge the new callback encoding \p NewCB into \p ExistingCallbacks.
MDNode *mergeCallbackEncodings(MDNode *ExistingCallbacks, MDNode *NewCB);
+ /// Return metadata feeding to the CodeGen about how to generate a function
+ /// prologue for the "function" santizier.
+ MDNode *createRTTIPointerPrologue(Constant *PrologueSig, Constant *RTTI);
+
//===------------------------------------------------------------------===//
// AA metadata.
//===------------------------------------------------------------------===//
diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 3e8e190eecc3..091f16567a36 100644
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -844,6 +844,24 @@ void AsmPrinter::emitFunctionHeader() {
// Emit the prologue data.
if (F.hasPrologueData())
emitGlobalConstant(F.getParent()->getDataLayout(), F.getPrologueData());
+
+ // Emit the function prologue data for the indirect call sanitizer.
+ if (const MDNode *MD = F.getMetadata(LLVMContext::MD_func_sanitize)) {
+ assert(TM.getTargetTriple().getArch() == Triple::x86 ||
+ TM.getTargetTriple().getArch() == Triple::x86_64);
+ assert(MD->getNumOperands() == 2);
+
+ auto *PrologueSig = mdconst::extract<Constant>(MD->getOperand(0));
+ auto *FTRTTIProxy = mdconst::extract<Constant>(MD->getOperand(1));
+ assert(PrologueSig && FTRTTIProxy);
+ emitGlobalConstant(F.getParent()->getDataLayout(), PrologueSig);
+
+ const MCExpr *Proxy = lowerConstant(FTRTTIProxy);
+ const MCExpr *FnExp = MCSymbolRefExpr::create(CurrentFnSym, OutContext);
+ const MCExpr *PCRel = MCBinaryExpr::createSub(Proxy, FnExp, OutContext);
+ // Use 32 bit since only small code model is supported.
+ OutStreamer->emitValue(PCRel, 4u);
+ }
}
/// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
diff --git a/llvm/lib/IR/MDBuilder.cpp b/llvm/lib/IR/MDBuilder.cpp
index 35af8490287b..fc59fda9fe22 100644
--- a/llvm/lib/IR/MDBuilder.cpp
+++ b/llvm/lib/IR/MDBuilder.cpp
@@ -150,6 +150,14 @@ MDNode *MDBuilder::mergeCallbackEncodings(MDNode *ExistingCallbacks,
return MDNode::get(Context, Ops);
}
+MDNode *MDBuilder::createRTTIPointerPrologue(Constant *PrologueSig,
+ Constant *RTTI) {
+ SmallVector<Metadata *, 4> Ops;
+ Ops.push_back(createConstant(PrologueSig));
+ Ops.push_back(createConstant(RTTI));
+ return MDNode::get(Context, Ops);
+}
+
MDNode *MDBuilder::createAnonymousAARoot(StringRef Name, MDNode *Extra) {
SmallVector<Metadata *, 3> Args(1, nullptr);
if (Extra)
diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 8f94172a6402..9d11ef26c1f0 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -1405,7 +1405,11 @@ static GlobalVariable *createPrivateGlobalForSourceLoc(Module &M,
/// Check if \p G has been created by a trusted compiler pass.
static bool GlobalWasGeneratedByCompiler(GlobalVariable *G) {
// Do not instrument @llvm.global_ctors, @llvm.used, etc.
- if (G->getName().startswith("llvm."))
+ if (G->getName().startswith("llvm.") ||
+ // Do not instrument gcov counter arrays.
+ G->getName().startswith("__llvm_gcov_ctr") ||
+ // Do not instrument rtti proxy symbols for function sanitizer.
+ G->getName().startswith("__llvm_rtti_proxy"))
return true;
// Do not instrument asan globals.
@@ -1414,10 +1418,6 @@ static bool GlobalWasGeneratedByCompiler(GlobalVariable *G) {
G->getName().startswith(kODRGenPrefix))
return true;
- // Do not instrument gcov counter arrays.
- if (G->getName() == "__llvm_gcov_ctr")
- return true;
-
return false;
}
diff --git a/llvm/test/CodeGen/X86/func-sanitizer.ll b/llvm/test/CodeGen/X86/func-sanitizer.ll
new file mode 100644
index 000000000000..b8d96a346d0c
--- /dev/null
+++ b/llvm/test/CodeGen/X86/func-sanitizer.ll
@@ -0,0 +1,18 @@
+; RUN: llc -mtriple=x86_64-unknown-linux-gnu < %s | FileCheck %s
+
+; CHECK: _Z3funv:
+; CHECK: .cfi_startproc
+; CHECK: .long 846595819
+; CHECK: .long .L__llvm_rtti_proxy-_Z3funv
+; CHECK: .L__llvm_rtti_proxy:
+; CHECK: .quad i
+; CHECK: .size .L__llvm_rtti_proxy, 8
+
+@i = linkonce_odr constant i32 1
+@__llvm_rtti_proxy = private unnamed_addr constant i32* @i
+
+define dso_local void @_Z3funv() !func_sanitize !0 {
+ ret void
+}
+
+!0 = !{i32 846595819, i32** @__llvm_rtti_proxy}
From 640a28cc0fe12741daa4c22f34b618ad57195528 Mon Sep 17 00:00:00 2001
From: Yuanfang Chen <yuanfang.chen@sony.com>
Date: Mon, 27 Jun 2022 11:36:32 -0700
Subject: [PATCH 2/2] [Coroutine] Remove the '!func_sanitize' metadata for
split functions
There is no proper RTTI for these split functions. So just delete the
metadata.
Fixes https://github.com/llvm/llvm-project/issues/49689.
Reviewed By: rjmccall
Differential Revision: https://reviews.llvm.org/D116130
(cherry picked from commit e2e9e708e5c2c3d5357b4bb355285ef55cd060d9)
---
llvm/lib/Transforms/Coroutines/CoroSplit.cpp | 6 ++++++
llvm/test/Transforms/Coroutines/coro-split-00.ll | 12 +++++++-----
2 files changed, 13 insertions(+), 5 deletions(-)
diff --git a/llvm/lib/Transforms/Coroutines/CoroSplit.cpp b/llvm/lib/Transforms/Coroutines/CoroSplit.cpp
index b5129809c6a6..78134fd297da 100644
--- a/llvm/lib/Transforms/Coroutines/CoroSplit.cpp
+++ b/llvm/lib/Transforms/Coroutines/CoroSplit.cpp
@@ -923,6 +923,12 @@ void CoroCloner::create() {
NewF->setVisibility(savedVisibility);
NewF->setUnnamedAddr(savedUnnamedAddr);
NewF->setDLLStorageClass(savedDLLStorageClass);
+ // The function sanitizer metadata needs to match the signature of the
+ // function it is being attached to. However this does not hold for split
+ // functions here. Thus remove the metadata for split functions.
+ if (Shape.ABI == coro::ABI::Switch &&
+ NewF->hasMetadata(LLVMContext::MD_func_sanitize))
+ NewF->eraseMetadata(LLVMContext::MD_func_sanitize);
// Replace the attributes of the new function:
auto OrigAttrs = NewF->getAttributes();
diff --git a/llvm/test/Transforms/Coroutines/coro-split-00.ll b/llvm/test/Transforms/Coroutines/coro-split-00.ll
index d5c6279a6a87..cf2dc10549e7 100644
--- a/llvm/test/Transforms/Coroutines/coro-split-00.ll
+++ b/llvm/test/Transforms/Coroutines/coro-split-00.ll
@@ -1,7 +1,7 @@
; Tests that coro-split pass splits the coroutine into f, f.resume and f.destroy
; RUN: opt < %s -passes='cgscc(coro-split),simplifycfg,early-cse' -S | FileCheck %s
-define i8* @f() "coroutine.presplit"="1" {
+define i8* @f() "coroutine.presplit"="1" !func_sanitize !0 {
entry:
%id = call token @llvm.coro.id(i32 0, i8* null, i8* null, i8* null)
%need.alloc = call i1 @llvm.coro.alloc(token %id)
@@ -32,7 +32,7 @@ suspend:
ret i8* %hdl
}
-; CHECK-LABEL: @f(
+; CHECK-LABEL: @f() !func_sanitize !0 {
; CHECK: call i8* @malloc
; CHECK: @llvm.coro.begin(token %id, i8* %phi)
; CHECK: store void (%f.Frame*)* @f.resume, void (%f.Frame*)** %resume.addr
@@ -43,7 +43,7 @@ suspend:
; CHECK-NOT: call void @free(
; CHECK: ret i8* %hdl
-; CHECK-LABEL: @f.resume(
+; CHECK-LABEL: @f.resume({{.*}}) {
; CHECK-NOT: call i8* @malloc
; CHECK-NOT: call void @print(i32 0)
; CHECK: call void @print(i32 1)
@@ -51,13 +51,13 @@ suspend:
; CHECK: call void @free(
; CHECK: ret void
-; CHECK-LABEL: @f.destroy(
+; CHECK-LABEL: @f.destroy({{.*}}) {
; CHECK-NOT: call i8* @malloc
; CHECK-NOT: call void @print(
; CHECK: call void @free(
; CHECK: ret void
-; CHECK-LABEL: @f.cleanup(
+; CHECK-LABEL: @f.cleanup({{.*}}) {
; CHECK-NOT: call i8* @malloc
; CHECK-NOT: call void @print(
; CHECK-NOT: call void @free(
@@ -77,3 +77,5 @@ declare i1 @llvm.coro.end(i8*, i1)
declare noalias i8* @malloc(i32)
declare void @print(i32)
declare void @free(i8*) willreturn
+
+!0 = !{i32 846595819, i8** null}