llvm-project/compiler-rt/lib/asan/asan_malloc_win.cc

87 lines
2.7 KiB
C++

//===-- asan_malloc_win.cc --------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is a part of AddressSanitizer, an address sanity checker.
//
// Windows-specific malloc interception.
//===----------------------------------------------------------------------===//
#ifdef _WIN32
#include "asan_allocator.h"
#include "asan_interceptors.h"
#include "asan_internal.h"
#include "asan_stack.h"
#include "interception/interception.h"
// ---------------------- Replacement functions ---------------- {{{1
using namespace __asan; // NOLINT
// FIXME: Simply defining functions with the same signature in *.obj
// files overrides the standard functions in *.lib
// This works well for simple helloworld-like tests but might need to be
// revisited in the future.
extern "C" {
void free(void *ptr) {
GET_STACK_TRACE_HERE_FOR_FREE(ptr);
return asan_free(ptr, &stack);
}
void *malloc(size_t size) {
GET_STACK_TRACE_HERE_FOR_MALLOC;
return asan_malloc(size, &stack);
}
void *calloc(size_t nmemb, size_t size) {
GET_STACK_TRACE_HERE_FOR_MALLOC;
return asan_calloc(nmemb, size, &stack);
}
void *realloc(void *ptr, size_t size) {
GET_STACK_TRACE_HERE_FOR_MALLOC;
return asan_realloc(ptr, size, &stack);
}
} // extern "C"
using __interception::GetRealFunctionAddress;
// We don't want to include "windows.h" in this file to avoid extra attributes
// set on malloc/free etc (e.g. dllimport), so declare a few things manually:
extern "C" int __stdcall VirtualProtect(void* addr, size_t size,
DWORD prot, DWORD *old_prot);
const int PAGE_EXECUTE_READWRITE = 0x40;
namespace __asan {
void ReplaceSystemMalloc() {
#ifdef _WIN64
# error ReplaceSystemMalloc was not tested on x64
#endif
char *crt_malloc;
if (GetRealFunctionAddress("malloc", (void**)&crt_malloc)) {
// Replace malloc in the CRT dll with a jump to our malloc.
DWORD old_prot, unused;
CHECK(VirtualProtect(crt_malloc, 16, PAGE_EXECUTE_READWRITE, &old_prot));
REAL(memset)(crt_malloc, 0xCC /* int 3 */, 16); // just in case.
uintptr_t jmp_offset = (intptr_t)malloc - (intptr_t)crt_malloc - 5;
crt_malloc[0] = 0xE9; // jmp, should be followed by an offset.
REAL(memcpy)(crt_malloc + 1, &jmp_offset, sizeof(jmp_offset));
CHECK(VirtualProtect(crt_malloc, 16, old_prot, &unused));
// FYI: FlushInstructionCache is needed on Itanium etc but not on x86/x64.
}
// FIXME: investigate whether anything else is needed.
}
} // namespace __asan
#endif // _WIN32