[scudo] Overhaul malloc related interceptors

[cryptoad]

Summary

This is a follow-up to D42506.

There are a few of things that bothered me about scudo_interceptors.cpp:

• the filename is a misnomer: it intercepts some functions, but the rest (C++) is actually in scudo_new_delete.cpp. I feel like scudo_malloc.cpp is more appropriate (ASan uses the same naming scheme);
• we do not need "full" interceptors, since we are never accessing the unsanitized version of the functions, we just need the extern "C" INTERCEPTOR_ATTRIBUTE part of it to just call our functions;
• a couple of functions where duplicated while they could just be ALIAS'd;
• use the SANITIZER_INTERCEPT_* defines to hide the unneeded interceptors;
• use SIZE_T instead of uptr: while it's the same behind the curtain, the former is meant for this use case.

In the end there is no functional change on the currently supported platforms
(Linux, Android).

lib/scudo/CMakeLists.txt

 add_compiler_rt_component(scudo)
 
 include_directories(..)
 
 set(SCUDO_CFLAGS ${SANITIZER_COMMON_CFLAGS})
 # SANITIZER_COMMON_CFLAGS include -fno-builtin, but we actually want builtins!
 list(APPEND SCUDO_CFLAGS -fbuiltin)
 append_rtti_flag(OFF SCUDO_CFLAGS)
 
 set(SCUDO_DYNAMIC_LINK_FLAGS ${SANITIZER_COMMON_LINK_FLAGS})
 
 set(SCUDO_SOURCES
   scudo_allocator.cpp
-  scudo_flags.cpp
   scudo_crc32.cpp
-  scudo_interceptors.cpp
+  scudo_flags.cpp
+  scudo_malloc.cpp
   scudo_termination.cpp
   scudo_tsd_exclusive.cpp
   scudo_tsd_shared.cpp
   scudo_utils.cpp)
 
 set(SCUDO_CXX_SOURCES
   scudo_new_delete.cpp)
 

lib/scudo/scudo_interceptors.cpp

-//===-- scudo_interceptors.cpp ----------------------------------*- C++ -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-///
-/// Interceptors for malloc related functions.
-///
-//===----------------------------------------------------------------------===//
-
-#include "scudo_allocator.h"
-
-#include "interception/interception.h"
-
-using namespace __scudo;
-
-INTERCEPTOR(void, free, void *ptr) {
-  scudoFree(ptr, FromMalloc);
-}
-
-INTERCEPTOR(void, cfree, void *ptr) {
-  scudoFree(ptr, FromMalloc);
-}
-
-INTERCEPTOR(void*, malloc, uptr size) {
-  return scudoMalloc(size, FromMalloc);
-}
-
-INTERCEPTOR(void*, realloc, void *ptr, uptr size) {
-  return scudoRealloc(ptr, size);
-}
-
-INTERCEPTOR(void*, calloc, uptr nmemb, uptr size) {
-  return scudoCalloc(nmemb, size);
-}
-
-INTERCEPTOR(void*, valloc, uptr size) {
-  return scudoValloc(size);
-}
-
-INTERCEPTOR(void*, memalign, uptr alignment, uptr size) {
-  return scudoMemalign(alignment, size);
-}
-
-INTERCEPTOR(void*, __libc_memalign, uptr alignment, uptr size) {
-  return scudoMemalign(alignment, size);
-}
-
-INTERCEPTOR(void*, pvalloc, uptr size) {
-  return scudoPvalloc(size);
-}
-
-INTERCEPTOR(void*, aligned_alloc, uptr alignment, uptr size) {
-  return scudoAlignedAlloc(alignment, size);
-}
-
-INTERCEPTOR(int, posix_memalign, void **memptr, uptr alignment, uptr size) {
-  return scudoPosixMemalign(memptr, alignment, size);
-}
-
-INTERCEPTOR(uptr, malloc_usable_size, void *ptr) {
-  return scudoMallocUsableSize(ptr);
-}
-
-INTERCEPTOR(int, mallopt, int cmd, int value) {
-  return -1;
-}

lib/scudo/scudo_malloc.cpp

+//===-- scudo_malloc.cpp ----------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// Interceptors for malloc related functions.
+///
+//===----------------------------------------------------------------------===//
+
+#include "scudo_allocator.h"
+
+#include "interception/interception.h"
+#include "sanitizer_common/sanitizer_platform_interceptors.h"
+
+using namespace __scudo;
+
+extern "C" {
+INTERCEPTOR_ATTRIBUTE void free(void *ptr) {
+  scudoFree(ptr, FromMalloc);
+}
+
+INTERCEPTOR_ATTRIBUTE void *malloc(SIZE_T size) {
+  return scudoMalloc(size, FromMalloc);
+}
+
+INTERCEPTOR_ATTRIBUTE void *realloc(void *ptr, SIZE_T size) {
+  return scudoRealloc(ptr, size);
+}
+
+INTERCEPTOR_ATTRIBUTE void *calloc(SIZE_T nmemb, SIZE_T size) {
+  return scudoCalloc(nmemb, size);
+}
+
+INTERCEPTOR_ATTRIBUTE void *valloc(SIZE_T size) {
+  return scudoValloc(size);
+}
+
+INTERCEPTOR_ATTRIBUTE
+int posix_memalign(void **memptr, SIZE_T alignment, SIZE_T size) {
+  return scudoPosixMemalign(memptr, alignment, size);
+}
+
+#if SANITIZER_INTERCEPT_CFREE
+INTERCEPTOR_ATTRIBUTE void cfree(void *ptr) ALIAS("free");
+#endif
+
+#if SANITIZER_INTERCEPT_MEMALIGN
+INTERCEPTOR_ATTRIBUTE void *memalign(SIZE_T alignment, SIZE_T size) {
+  return scudoMemalign(alignment, size);
+}
+
+INTERCEPTOR_ATTRIBUTE
+void *__libc_memalign(SIZE_T alignment, SIZE_T size) ALIAS("memalign");
+#endif
+
+#if SANITIZER_INTERCEPT_PVALLOC
+INTERCEPTOR_ATTRIBUTE void *pvalloc(SIZE_T size) {
+  return scudoPvalloc(size);
+}
+#endif
+
+#if SANITIZER_INTERCEPT_ALIGNED_ALLOC
+INTERCEPTOR_ATTRIBUTE void *aligned_alloc(SIZE_T alignment, SIZE_T size) {
+  return scudoAlignedAlloc(alignment, size);
+}
+#endif
+
+#if SANITIZER_INTERCEPT_MALLOC_USABLE_SIZE
+INTERCEPTOR_ATTRIBUTE SIZE_T malloc_usable_size(void *ptr) {
+  return scudoMallocUsableSize(ptr);
+}
+#endif
+
+#if SANITIZER_INTERCEPT_MALLOPT_AND_MALLINFO
+INTERCEPTOR_ATTRIBUTE int mallopt(int cmd, int value) {
+  return -1;
+}
+#endif
+}  // extern "C"