[sanitizer] Use -Wl,-z,global on Android

Kostya Kortchinsky · Kostya Kortchinsky · commit 4a547fb62d40 · 2018-07-13T15:31:05.000Z
Summary: Use `-Wl,-z,global` for all Sanitizer shared libraries on Android. We want them to be in the global group (https://android.googlesource.com/platform/bionic/+/master/android-changes-for-ndk-developers.md#changes-to-library-search-order) to avoid any alloc/dealloc mismatch between the libc allocator & said library. `audioserver` was one of the binary that exhibited the problem with Scudo, this seems to fix it. [edited for accuracy] Reviewers: eugenis, alekseyshl Reviewed By: eugenis Subscribers: kubamracek, srhines, mgorny, delcypher, #sanitizers, llvm-commits Differential Revision: https://reviews.llvm.org/D49198 llvm-svn: 337010
diff --git a/compiler-rt/CMakeLists.txt b/compiler-rt/CMakeLists.txt
@@ -333,6 +333,14 @@ endif()
 
 append_list_if(COMPILER_RT_HAS_LIBC c SANITIZER_COMMON_LINK_LIBS)
 
+if(ANDROID)
+# Put the Sanitizer shared libraries in the global group. For more details, see
+# android-changes-for-ndk-developers.md#changes-to-library-search-order
+  if (COMPILER_RT_HAS_Z_GLOBAL)
+    list(APPEND SANITIZER_COMMON_LINK_FLAGS -Wl,-z,global)
+  endif()
+endif()
+
 if("${CMAKE_SYSTEM_NAME}" STREQUAL "Fuchsia")
   list(APPEND SANITIZER_COMMON_LINK_FLAGS -Wl,-z,defs,-z,now,-z,relro)
   list(APPEND SANITIZER_COMMON_LINK_LIBS zircon)
diff --git a/compiler-rt/lib/asan/CMakeLists.txt b/compiler-rt/lib/asan/CMakeLists.txt
@@ -75,20 +75,6 @@ append_rtti_flag(OFF ASAN_CFLAGS)
 
 set(ASAN_DYNAMIC_LINK_FLAGS ${SANITIZER_COMMON_LINK_FLAGS})
 
-if(ANDROID)
-# On Android, -z global does not do what it is documented to do.
-# On Android, -z global moves the library ahead in the lookup order,
-# placing it right after the LD_PRELOADs. This is used to compensate for the fact
-# that Android linker does not look at the dependencies of the main executable
-# that aren't dependencies of the current DSO when resolving symbols from said DSO.
-# As a net result, this allows running ASan executables without LD_PRELOAD-ing the
-# ASan runtime library.
-# The above is applicable to L MR1 or newer.
-  if (COMPILER_RT_HAS_Z_GLOBAL)
-    list(APPEND ASAN_DYNAMIC_LINK_FLAGS -Wl,-z,global)
-  endif()
-endif()
-
 set(ASAN_DYNAMIC_DEFINITIONS
   ${ASAN_COMMON_DEFINITIONS} ASAN_DYNAMIC=1)
 append_list_if(WIN32 INTERCEPTION_DYNAMIC_CRT ASAN_DYNAMIC_DEFINITIONS)
diff --git a/compiler-rt/lib/hwasan/CMakeLists.txt b/compiler-rt/lib/hwasan/CMakeLists.txt
@@ -36,20 +36,6 @@ append_list_if(COMPILER_RT_HAS_FFREESTANDING_FLAG -ffreestanding HWASAN_RTL_CFLA
 
 set(HWASAN_DYNAMIC_LINK_FLAGS ${SANITIZER_COMMON_LINK_FLAGS})
 
-if(ANDROID)
-# On Android, -z global does not do what it is documented to do.
-# On Android, -z global moves the library ahead in the lookup order,
-# placing it right after the LD_PRELOADs. This is used to compensate for the fact
-# that Android linker does not look at the dependencies of the main executable
-# that aren't dependencies of the current DSO when resolving symbols from said DSO.
-# As a net result, this allows running ASan executables without LD_PRELOAD-ing the
-# ASan runtime library.
-# The above is applicable to L MR1 or newer.
-  if (COMPILER_RT_HAS_Z_GLOBAL)
-    list(APPEND HWASAN_DYNAMIC_LINK_FLAGS -Wl,-z,global)
-  endif()
-endif()
-
 set(HWASAN_DYNAMIC_CFLAGS ${HWASAN_RTL_CFLAGS})
 append_list_if(COMPILER_RT_HAS_FTLS_MODEL_INITIAL_EXEC
   -ftls-model=initial-exec HWASAN_DYNAMIC_CFLAGS)
