[compiler-rt] [NFC][asan] Use Thread Safety Analysis in asan_globals.cpp (PR #101574)

Vitaly Buka via llvm-commits llvm-commits at lists.llvm.org
Thu Aug 1 23:39:29 PDT 2024


https://github.com/vitalybuka updated https://github.com/llvm/llvm-project/pull/101574

>From d84f89010591bb3d28396071153d346343a22d73 Mon Sep 17 00:00:00 2001
From: Vitaly Buka <vitalybuka at google.com>
Date: Thu, 1 Aug 2024 15:47:44 -0700
Subject: [PATCH] =?UTF-8?q?[=F0=9D=98=80=F0=9D=97=BD=F0=9D=97=BF]=20initia?=
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Created using spr 1.3.4
---
 compiler-rt/lib/asan/asan_globals.cpp | 36 ++++++++++++++++-----------
 1 file changed, 22 insertions(+), 14 deletions(-)

diff --git a/compiler-rt/lib/asan/asan_globals.cpp b/compiler-rt/lib/asan/asan_globals.cpp
index 0445a1d44f682..9766488fed0c9 100644
--- a/compiler-rt/lib/asan/asan_globals.cpp
+++ b/compiler-rt/lib/asan/asan_globals.cpp
@@ -27,6 +27,7 @@
 #include "sanitizer_common/sanitizer_placement_new.h"
 #include "sanitizer_common/sanitizer_stackdepot.h"
 #include "sanitizer_common/sanitizer_symbolizer.h"
+#include "sanitizer_common/sanitizer_thread_safety.h"
 
 namespace __asan {
 
@@ -40,8 +41,9 @@ typedef IntrusiveList<GlobalListNode> ListOfGlobals;
 typedef DenseMap<uptr, ListOfGlobals> MapOfGlobals;
 
 static Mutex mu_for_globals;
-static ListOfGlobals list_of_all_globals;
-static MapOfGlobals map_of_globals_by_indicator;
+static ListOfGlobals list_of_all_globals SANITIZER_GUARDED_BY(mu_for_globals);
+static MapOfGlobals map_of_globals_by_indicator
+    SANITIZER_GUARDED_BY(mu_for_globals);
 
 static const int kDynamicInitGlobalsInitialCapacity = 512;
 struct DynInitGlobal {
@@ -50,7 +52,8 @@ struct DynInitGlobal {
 };
 typedef InternalMmapVector<DynInitGlobal> VectorOfGlobals;
 // Lazy-initialized and never deleted.
-static VectorOfGlobals *dynamic_init_globals;
+static VectorOfGlobals *dynamic_init_globals
+    SANITIZER_GUARDED_BY(mu_for_globals);
 
 // We want to remember where a certain range of globals was registered.
 struct GlobalRegistrationSite {
@@ -147,7 +150,8 @@ enum GlobalSymbolState {
 // Check ODR violation for given global G via special ODR indicator. We use
 // this method in case compiler instruments global variables through their
 // local aliases.
-static void CheckODRViolationViaIndicator(const Global *g) {
+static void CheckODRViolationViaIndicator(const Global *g)
+    SANITIZER_REQUIRES(mu_for_globals) {
   // Instrumentation requests to skip ODR check.
   if (g->odr_indicator == UINTPTR_MAX)
     return;
@@ -175,7 +179,8 @@ static void CheckODRViolationViaIndicator(const Global *g) {
 // Check ODR violation for given global G by checking if it's already poisoned.
 // We use this method in case compiler doesn't use private aliases for global
 // variables.
-static void CheckODRViolationViaPoisoning(const Global *g) {
+static void CheckODRViolationViaPoisoning(const Global *g)
+    SANITIZER_REQUIRES(mu_for_globals) {
   if (__asan_region_is_poisoned(g->beg, g->size_with_redzone)) {
     // This check may not be enough: if the first global is much larger
     // the entire redzone of the second global may be within the first global.
@@ -213,7 +218,7 @@ static inline bool UseODRIndicator(const Global *g) {
 // Register a global variable.
 // This function may be called more than once for every global
 // so we store the globals in a map.
-static void RegisterGlobal(const Global *g) {
+static void RegisterGlobal(const Global *g) SANITIZER_REQUIRES(mu_for_globals) {
   CHECK(AsanInited());
   if (flags()->report_globals >= 2)
     ReportGlobal(*g, "Added");
@@ -253,7 +258,8 @@ static void RegisterGlobal(const Global *g) {
   }
 }
 
-static void UnregisterGlobal(const Global *g) {
+static void UnregisterGlobal(const Global *g)
+    SANITIZER_REQUIRES(mu_for_globals) {
   CHECK(AsanInited());
   if (flags()->report_globals >= 2)
     ReportGlobal(*g, "Removed");
@@ -275,8 +281,10 @@ static void UnregisterGlobal(const Global *g) {
 }
 
 void StopInitOrderChecking() {
+  if (!flags()->check_initialization_order)
+    return;
   Lock lock(&mu_for_globals);
-  if (!flags()->check_initialization_order || !dynamic_init_globals)
+  if (!dynamic_init_globals)
     return;
   flags()->check_initialization_order = false;
   for (uptr i = 0, n = dynamic_init_globals->size(); i < n; ++i) {
@@ -441,14 +449,14 @@ void __asan_unregister_globals(__asan_global *globals, uptr n) {
 // poisons all global variables not defined in this TU, so that a dynamic
 // initializer can only touch global variables in the same TU.
 void __asan_before_dynamic_init(const char *module_name) {
-  if (!flags()->check_initialization_order ||
-      !CanPoisonMemory() ||
-      !dynamic_init_globals)
+  if (!flags()->check_initialization_order || !CanPoisonMemory())
     return;
   bool strict_init_order = flags()->strict_init_order;
   CHECK(module_name);
   CHECK(AsanInited());
   Lock lock(&mu_for_globals);
+  if (!dynamic_init_globals)
+    return;
   if (flags()->report_globals >= 3)
     Printf("DynInitPoison module: %s\n", module_name);
   for (uptr i = 0, n = dynamic_init_globals->size(); i < n; ++i) {
@@ -467,12 +475,12 @@ void __asan_before_dynamic_init(const char *module_name) {
 // 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 (!flags()->check_initialization_order ||
-      !CanPoisonMemory() ||
-      !dynamic_init_globals)
+  if (!flags()->check_initialization_order || !CanPoisonMemory())
     return;
   CHECK(AsanInited());
   Lock lock(&mu_for_globals);
+  if (!dynamic_init_globals)
+    return;
   // FIXME: Optionally report that we're unpoisoning globals from a module.
   for (uptr i = 0, n = dynamic_init_globals->size(); i < n; ++i) {
     DynInitGlobal &dyn_g = (*dynamic_init_globals)[i];



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