4f298d4efa
This PR upstreams support for PtrAuth in the LLDB expression evaluator. It's a rebased version of an older patch in the Swiftlang repo (https://github.com/swiftlang/llvm-project/pull/5012) but adapted to not rely on `GlobalPtrAuthInfo.h`. I followed Anton's advice, and instead of iterating over all globals and hack on wrappers, the pass now iterates over all global uses and fixes up ConstantPtrAuth expressions if any. This is one of the last large chunks of downstream PtrAuth code in LLDB, and the primary blocker for running the LLDB test suite in arm64e mode on Apple Silicon, which I'd really like to make the default in the future.
226 lines
8.0 KiB
C++
226 lines
8.0 KiB
C++
//===-- ClangFunctionCaller.cpp -------------------------------------------===//
|
|
//
|
|
// 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 "ClangFunctionCaller.h"
|
|
|
|
#include "ASTStructExtractor.h"
|
|
#include "ClangExpressionParser.h"
|
|
|
|
#include "clang/AST/ASTContext.h"
|
|
#include "clang/AST/RecordLayout.h"
|
|
#include "clang/CodeGen/CodeGenAction.h"
|
|
#include "clang/CodeGen/ModuleBuilder.h"
|
|
#include "clang/Frontend/CompilerInstance.h"
|
|
#include "llvm/ADT/StringRef.h"
|
|
#include "llvm/ExecutionEngine/ExecutionEngine.h"
|
|
#include "llvm/IR/Module.h"
|
|
#include "llvm/TargetParser/Triple.h"
|
|
|
|
#include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
|
|
#include "lldb/Core/Module.h"
|
|
#include "lldb/Expression/IRExecutionUnit.h"
|
|
#include "lldb/Interpreter/CommandReturnObject.h"
|
|
#include "lldb/Symbol/Function.h"
|
|
#include "lldb/Symbol/Type.h"
|
|
#include "lldb/Target/ExecutionContext.h"
|
|
#include "lldb/Target/Process.h"
|
|
#include "lldb/Target/RegisterContext.h"
|
|
#include "lldb/Target/Target.h"
|
|
#include "lldb/Target/Thread.h"
|
|
#include "lldb/Target/ThreadPlan.h"
|
|
#include "lldb/Target/ThreadPlanCallFunction.h"
|
|
#include "lldb/Utility/DataExtractor.h"
|
|
#include "lldb/Utility/LLDBLog.h"
|
|
#include "lldb/Utility/Log.h"
|
|
#include "lldb/Utility/State.h"
|
|
#include "lldb/ValueObject/ValueObject.h"
|
|
#include "lldb/ValueObject/ValueObjectList.h"
|
|
|
|
using namespace lldb_private;
|
|
|
|
char ClangFunctionCaller::ID;
|
|
|
|
// ClangFunctionCaller constructor
|
|
ClangFunctionCaller::ClangFunctionCaller(ExecutionContextScope &exe_scope,
|
|
const CompilerType &return_type,
|
|
const Address &functionAddress,
|
|
const ValueList &arg_value_list,
|
|
const char *name)
|
|
: FunctionCaller(exe_scope, return_type, functionAddress, arg_value_list,
|
|
name),
|
|
m_type_system_helper(*this) {
|
|
m_jit_process_wp = lldb::ProcessWP(exe_scope.CalculateProcess());
|
|
// Can't make a ClangFunctionCaller without a process.
|
|
assert(m_jit_process_wp.lock());
|
|
}
|
|
|
|
// Destructor
|
|
ClangFunctionCaller::~ClangFunctionCaller() = default;
|
|
|
|
unsigned
|
|
|
|
ClangFunctionCaller::CompileFunction(lldb::ThreadSP thread_to_use_sp,
|
|
DiagnosticManager &diagnostic_manager) {
|
|
if (m_compiled)
|
|
return 0;
|
|
|
|
// Compilation might call code, make sure to keep on the thread the caller
|
|
// indicated.
|
|
ThreadList::ExpressionExecutionThreadPusher execution_thread_pusher(
|
|
thread_to_use_sp);
|
|
|
|
// FIXME: How does clang tell us there's no return value? We need to handle
|
|
// that case.
|
|
unsigned num_errors = 0;
|
|
|
|
std::string return_type_str(
|
|
m_function_return_type.GetTypeName().AsCString(""));
|
|
|
|
// Cons up the function we're going to wrap our call in, then compile it...
|
|
// We declare the function "extern "C"" because the compiler might be in C++
|
|
// mode which would mangle the name and then we couldn't find it again...
|
|
m_wrapper_function_text.clear();
|
|
m_wrapper_function_text.append("extern \"C\" void ");
|
|
m_wrapper_function_text.append(m_wrapper_function_name);
|
|
m_wrapper_function_text.append(" (void *input)\n{\n struct ");
|
|
m_wrapper_function_text.append(m_wrapper_struct_name);
|
|
m_wrapper_function_text.append(" \n {\n");
|
|
m_wrapper_function_text.append(" ");
|
|
m_wrapper_function_text.append(return_type_str);
|
|
m_wrapper_function_text.append(" (*fn_ptr) (");
|
|
|
|
// Get the number of arguments. If we have a function type and it is
|
|
// prototyped, trust that, otherwise use the values we were given.
|
|
|
|
// FIXME: This will need to be extended to handle Variadic functions. We'll
|
|
// need
|
|
// to pull the defined arguments out of the function, then add the types from
|
|
// the arguments list for the variable arguments.
|
|
|
|
uint32_t num_args = UINT32_MAX;
|
|
bool trust_function = false;
|
|
// GetArgumentCount returns -1 for an unprototyped function.
|
|
CompilerType function_clang_type;
|
|
if (m_function_ptr) {
|
|
function_clang_type = m_function_ptr->GetCompilerType();
|
|
if (function_clang_type) {
|
|
int num_func_args = function_clang_type.GetFunctionArgumentCount();
|
|
if (num_func_args >= 0) {
|
|
trust_function = true;
|
|
num_args = num_func_args;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (num_args == UINT32_MAX)
|
|
num_args = m_arg_values.GetSize();
|
|
|
|
std::string args_buffer; // This one stores the definition of all the args in
|
|
// "struct caller".
|
|
std::string args_list_buffer; // This one stores the argument list called from
|
|
// the structure.
|
|
for (size_t i = 0; i < num_args; i++) {
|
|
std::string type_name;
|
|
|
|
if (trust_function) {
|
|
type_name = function_clang_type.GetFunctionArgumentTypeAtIndex(i)
|
|
.GetTypeName()
|
|
.AsCString("");
|
|
} else {
|
|
CompilerType clang_qual_type =
|
|
m_arg_values.GetValueAtIndex(i)->GetCompilerType();
|
|
if (clang_qual_type) {
|
|
type_name = clang_qual_type.GetTypeName().AsCString("");
|
|
} else {
|
|
diagnostic_manager.Printf(
|
|
lldb::eSeverityError,
|
|
"Could not determine type of input value %" PRIu64 ".",
|
|
(uint64_t)i);
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
m_wrapper_function_text.append(type_name);
|
|
if (i < num_args - 1)
|
|
m_wrapper_function_text.append(", ");
|
|
|
|
char arg_buf[32];
|
|
args_buffer.append(" ");
|
|
args_buffer.append(type_name);
|
|
snprintf(arg_buf, 31, "arg_%" PRIu64, (uint64_t)i);
|
|
args_buffer.push_back(' ');
|
|
args_buffer.append(arg_buf);
|
|
args_buffer.append(";\n");
|
|
|
|
args_list_buffer.append("__lldb_fn_data->");
|
|
args_list_buffer.append(arg_buf);
|
|
if (i < num_args - 1)
|
|
args_list_buffer.append(", ");
|
|
}
|
|
m_wrapper_function_text.append(
|
|
");\n"); // Close off the function calling prototype.
|
|
|
|
m_wrapper_function_text.append(args_buffer);
|
|
|
|
m_wrapper_function_text.append(" ");
|
|
m_wrapper_function_text.append(return_type_str);
|
|
m_wrapper_function_text.append(" return_value;");
|
|
m_wrapper_function_text.append("\n };\n struct ");
|
|
m_wrapper_function_text.append(m_wrapper_struct_name);
|
|
m_wrapper_function_text.append("* __lldb_fn_data = (struct ");
|
|
m_wrapper_function_text.append(m_wrapper_struct_name);
|
|
m_wrapper_function_text.append(" *) input;\n");
|
|
|
|
m_wrapper_function_text.append(
|
|
" __lldb_fn_data->return_value = __lldb_fn_data->fn_ptr (");
|
|
m_wrapper_function_text.append(args_list_buffer);
|
|
m_wrapper_function_text.append(");\n}\n");
|
|
|
|
Log *log = GetLog(LLDBLog::Expressions);
|
|
LLDB_LOGF(log, "Expression: \n\n%s\n\n", m_wrapper_function_text.c_str());
|
|
|
|
// Okay, now compile this expression
|
|
|
|
lldb::ProcessSP jit_process_sp(m_jit_process_wp.lock());
|
|
if (jit_process_sp) {
|
|
// We will be passing in unauthenticated function addresses to the
|
|
// FunctionCaller code, so we need to force disable pointer auth
|
|
// codegen for this one code snippet.
|
|
const bool force_disable_ptrauth_codegen = true;
|
|
const bool generate_debug_info = true;
|
|
auto *clang_parser = new ClangExpressionParser(
|
|
jit_process_sp.get(), *this, generate_debug_info, diagnostic_manager,
|
|
std::vector<std::string>(), "<clang expression>",
|
|
force_disable_ptrauth_codegen);
|
|
num_errors = clang_parser->Parse(diagnostic_manager);
|
|
m_parser.reset(clang_parser);
|
|
} else {
|
|
diagnostic_manager.PutString(lldb::eSeverityError,
|
|
"no process - unable to inject function");
|
|
num_errors = 1;
|
|
}
|
|
|
|
m_compiled = (num_errors == 0);
|
|
|
|
if (!m_compiled)
|
|
return num_errors;
|
|
|
|
return num_errors;
|
|
}
|
|
|
|
char ClangFunctionCaller::ClangFunctionCallerHelper::ID;
|
|
|
|
clang::ASTConsumer *
|
|
ClangFunctionCaller::ClangFunctionCallerHelper::ASTTransformer(
|
|
clang::ASTConsumer *passthrough) {
|
|
m_struct_extractor = std::make_unique<ASTStructExtractor>(
|
|
passthrough, m_owner.GetWrapperStructName(), m_owner);
|
|
|
|
return m_struct_extractor.get();
|
|
}
|