[𝘀𝗽𝗿] changes to main this commit is based onusers/vitalybuka/spr/main.nfcmoduleutils-test-appendtoglobalctorsappendtoglobaldtors

Created using spr 1.3.4

[skip ci]

3 files changed, 121 insertions, 40 deletions

diff --git a/compiler-rt/lib/asan/asan_globals.cpp b/compiler-rt/lib/asan/asan_globals.cpp
index cc5308a..80030af 100644
--- a/compiler-rt/lib/asan/asan_globals.cpp
+++ b/compiler-rt/lib/asan/asan_globals.cpp
@@ -47,8 +47,6 @@ struct DynInitGlobal {
   bool initialized = false;
   DynInitGlobal *next = nullptr;
 };
-typedef IntrusiveList<DynInitGlobal> DynInitGlobals;
-static DynInitGlobals dynamic_init_globals SANITIZER_GUARDED_BY(mu_for_globals);
 
 // We want to remember where a certain range of globals was registered.
 struct GlobalRegistrationSite {
@@ -72,6 +70,25 @@ static ListOfGlobals &GlobalsByIndicator(uptr odr_indicator)
   return (*globals_by_indicator)[odr_indicator];
 }
 
+static const char *current_dynamic_init_module_name
+    SANITIZER_GUARDED_BY(mu_for_globals) = nullptr;
+
+using DynInitGlobalsByModule =
+    DenseMap<const char *, IntrusiveList<DynInitGlobal>>;
+
+// TODO: Add a NoDestroy helper, this patter is very common in sanitizers.
+static DynInitGlobalsByModule &DynInitGlobals()
+    SANITIZER_REQUIRES(mu_for_globals) {
+  static DynInitGlobalsByModule *globals_by_module = nullptr;
+  if (!globals_by_module) {
+    alignas(alignof(DynInitGlobalsByModule)) static char
+        placeholder[sizeof(DynInitGlobalsByModule)];
+    globals_by_module = new (placeholder) DynInitGlobalsByModule();
+  }
+
+  return *globals_by_module;
+}
+
 ALWAYS_INLINE void PoisonShadowForGlobal(const Global *g, u8 value) {
   FastPoisonShadow(g->beg, g->size_with_redzone, value);
 }
@@ -257,8 +274,8 @@ static void RegisterGlobal(const Global *g) SANITIZER_REQUIRES(mu_for_globals) {
   AddGlobalToList(list_of_all_globals, g);
 
   if (g->has_dynamic_init) {
-    dynamic_init_globals.push_back(new (GetGlobalLowLevelAllocator())
-                                       DynInitGlobal{*g, false});
+    DynInitGlobals()[g->module_name].push_back(
+        new (GetGlobalLowLevelAllocator()) DynInitGlobal{*g, false});
   }
 }
 
@@ -284,20 +301,42 @@ static void UnregisterGlobal(const Global *g)
   }
 }
 
-void StopInitOrderChecking() {
-  if (!flags()->check_initialization_order)
-    return;
-  Lock lock(&mu_for_globals);
-  flags()->check_initialization_order = false;
-  for (const DynInitGlobal &dyn_g : dynamic_init_globals) {
+static void UnpoisonDynamicGlobals(IntrusiveList<DynInitGlobal> &dyn_globals,
+                                   bool mark_initialized) {
+  for (auto &dyn_g : dyn_globals) {
     const Global *g = &dyn_g.g;
+    if (dyn_g.initialized)
+      continue;
     // Unpoison the whole global.
     PoisonShadowForGlobal(g, 0);
     // Poison redzones back.
     PoisonRedZones(*g);
+    if (mark_initialized)
+      dyn_g.initialized = true;
   }
 }
 
+static void PoisonDynamicGlobals(
+    const IntrusiveList<DynInitGlobal> &dyn_globals) {
+  for (auto &dyn_g : dyn_globals) {
+    const Global *g = &dyn_g.g;
+    if (dyn_g.initialized)
+      continue;
+    PoisonShadowForGlobal(g, kAsanInitializationOrderMagic);
+  }
+}
+
+void StopInitOrderChecking() {
+  if (!flags()->check_initialization_order)
+    return;
+  Lock lock(&mu_for_globals);
+  flags()->check_initialization_order = false;
+  DynInitGlobals().forEach([&](auto &kv) {
+    UnpoisonDynamicGlobals(kv.second, /*mark_initialized=*/false);
+    return true;
+  });
+}
+
 static bool IsASCII(unsigned char c) { return /*0x00 <= c &&*/ c <= 0x7F; }
 
 const char *MaybeDemangleGlobalName(const char *name) {
@@ -456,36 +495,73 @@ void __asan_before_dynamic_init(const char *module_name) {
   CHECK(module_name);
   CHECK(AsanInited());
   Lock lock(&mu_for_globals);
+  if (current_dynamic_init_module_name == module_name)
+    return;
   if (flags()->report_globals >= 3)
     Printf("DynInitPoison module: %s\n", module_name);
-  for (DynInitGlobal &dyn_g : dynamic_init_globals) {
-    const Global *g = &dyn_g.g;
-    if (dyn_g.initialized)
-      continue;
-    if (g->module_name != module_name)
-      PoisonShadowForGlobal(g, kAsanInitializationOrderMagic);
-    else if (!strict_init_order)
-      dyn_g.initialized = true;
+
+  if (current_dynamic_init_module_name == nullptr) {
+    // First call, poison all globals from other modules.
+    DynInitGlobals().forEach([&](auto &kv) {
+      if (kv.first != module_name) {
+        PoisonDynamicGlobals(kv.second);
+      } else {
+        UnpoisonDynamicGlobals(kv.second,
+                               /*mark_initialized=*/!strict_init_order);
+      }
+      return true;
+    });
+  } else {
+    // Module changed.
+    PoisonDynamicGlobals(DynInitGlobals()[current_dynamic_init_module_name]);
+    UnpoisonDynamicGlobals(DynInitGlobals()[module_name],
+                           /*mark_initialized=*/!strict_init_order);
   }
+  current_dynamic_init_module_name = module_name;
 }
 
+#if SANITIZER_CAN_USE_PREINIT_ARRAY
+static bool allow_after_dynamic_init = false;
+
+static void __attribute__((used)) AfterDynamicInit(void) {
+  if (flags()->report_globals >= 3)
+    Printf("AfterDynamicInit\n");
+  if (allow_after_dynamic_init)
+    return;
+  allow_after_dynamic_init = true;
+  __asan_after_dynamic_init();
+}
+
+// Maybe SANITIZER_CAN_USE_PREINIT_ARRAY is to conservative for `.init_array`.
+__attribute__((section(".init_array"), constructor(10000),
+               used)) static void (*__init)(void) = AfterDynamicInit;
+#endif  // SANITIZER_CAN_USE_PREINIT_ARRAY
+
 // This method runs immediately after dynamic initialization in each TU, when
 // all dynamically initialized globals except for those defined in the current
 // TU are poisoned.  It simply unpoisons all dynamically initialized globals.
 void __asan_after_dynamic_init() {
+#if SANITIZER_CAN_USE_PREINIT_ARRAY
+  // Ignore all callback until the first one from .init_array, which should
+  // happed after all C++ global constructors.
+  if (!allow_after_dynamic_init)
+    return;
+#endif
+
   if (!flags()->check_initialization_order || !CanPoisonMemory())
     return;
   CHECK(AsanInited());
   Lock lock(&mu_for_globals);
+  if (!current_dynamic_init_module_name)
+    return;
+
   if (flags()->report_globals >= 3)
     Printf("DynInitUnpoison\n");
-  for (const DynInitGlobal &dyn_g : dynamic_init_globals) {
-    const Global *g = &dyn_g.g;
-    if (!dyn_g.initialized) {
-      // Unpoison the whole global.
-      PoisonShadowForGlobal(g, 0);
-      // Poison redzones back.
-      PoisonRedZones(*g);
-    }
-  }
+
+  DynInitGlobals().forEach([&](auto &kv) {
+    UnpoisonDynamicGlobals(kv.second, /*mark_initialized=*/false);
+    return true;
+  });
+
+  current_dynamic_init_module_name = nullptr;
 }
diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 9fb1df7..04bebe3 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -1990,6 +1990,11 @@ void ModuleAddressSanitizer::createInitializerPoisonCalls(
       // Don't instrument CTORs that will run before asan.module_ctor.
       if (Priority->getLimitedValue() <= GetCtorAndDtorPriority(TargetTriple))
         continue;
+      if (Priority->getLimitedValue() == 65535) {
+        CS->setOperand(0,
+                       ConstantInt::getSigned(Priority->getType(),
+                                              Priority->getLimitedValue() - 1));
+      }
       poisonOneInitializer(*F, ModuleName);
     }
   }
diff --git a/llvm/unittests/Transforms/Utils/ModuleUtilsTest.cpp b/llvm/unittests/Transforms/Utils/ModuleUtilsTest.cpp
index e1bc58f..faca3bc 100644
--- a/llvm/unittests/Transforms/Utils/ModuleUtilsTest.cpp
+++ b/llvm/unittests/Transforms/Utils/ModuleUtilsTest.cpp
@@ -24,12 +24,12 @@ static std::unique_ptr<Module> parseIR(LLVMContext &C, const char *IR) {
   return Mod;
 }
 
-static int getUsedListSize(Module &M, StringRef Name) {
-  auto *UsedList = M.getGlobalVariable(Name);
-  if (!UsedList)
+static int getListSize(Module &M, StringRef Name) {
+  auto *List = M.getGlobalVariable(Name);
+  if (!List)
     return 0;
-  auto *UsedListBaseArrayType = cast<ArrayType>(UsedList->getValueType());
-  return UsedListBaseArrayType->getNumElements();
+  auto *T = cast<ArrayType>(List->getValueType());
+  return T->getNumElements();
 }
 
 TEST(ModuleUtils, AppendToUsedList1) {
@@ -41,13 +41,13 @@ TEST(ModuleUtils, AppendToUsedList1) {
   for (auto &G : M->globals()) {
     Globals.push_back(&G);
   }
-  EXPECT_EQ(0, getUsedListSize(*M, "llvm.compiler.used"));
+  EXPECT_EQ(0, getListSize(*M, "llvm.compiler.used"));
   appendToCompilerUsed(*M, Globals);
-  EXPECT_EQ(1, getUsedListSize(*M, "llvm.compiler.used"));
+  EXPECT_EQ(1, getListSize(*M, "llvm.compiler.used"));
 
-  EXPECT_EQ(0, getUsedListSize(*M, "llvm.used"));
+  EXPECT_EQ(0, getListSize(*M, "llvm.used"));
   appendToUsed(*M, Globals);
-  EXPECT_EQ(1, getUsedListSize(*M, "llvm.used"));
+  EXPECT_EQ(1, getListSize(*M, "llvm.used"));
 }
 
 TEST(ModuleUtils, AppendToUsedList2) {
@@ -59,11 +59,11 @@ TEST(ModuleUtils, AppendToUsedList2) {
   for (auto &G : M->globals()) {
     Globals.push_back(&G);
   }
-  EXPECT_EQ(0, getUsedListSize(*M, "llvm.compiler.used"));
+  EXPECT_EQ(0, getListSize(*M, "llvm.compiler.used"));
   appendToCompilerUsed(*M, Globals);
-  EXPECT_EQ(1, getUsedListSize(*M, "llvm.compiler.used"));
+  EXPECT_EQ(1, getListSize(*M, "llvm.compiler.used"));
 
-  EXPECT_EQ(0, getUsedListSize(*M, "llvm.used"));
+  EXPECT_EQ(0, getListSize(*M, "llvm.used"));
   appendToUsed(*M, Globals);
-  EXPECT_EQ(1, getUsedListSize(*M, "llvm.used"));
+  EXPECT_EQ(1, getListSize(*M, "llvm.used"));
 }