Revert "[hwasan] Record and display stack history in stack-based reports."

This reverts commit r342921: test failures on clang-cmake-arm* bots.

llvm-svn: 342922

Author: eugenis

compiler-rt/lib/hwasan/CMakeLists.txt

@@ -10,7 +10,6 @@ set(HWASAN_RTL_SOURCES
   hwasan_poisoning.cc
   hwasan_report.cc
   hwasan_thread.cc
-  hwasan_thread_list.cc
   )
 
 set(HWASAN_RTL_CXX_SOURCES
@@ -26,9 +25,8 @@ set(HWASAN_RTL_HEADERS
   hwasan_mapping.h
   hwasan_poisoning.h
   hwasan_report.h
-  hwasan_thread.h
-  hwasan_thread_list.h
-  )
+  hwasan_thread.h)
+
 
 set(HWASAN_DEFINITIONS)
 append_list_if(COMPILER_RT_HWASAN_WITH_INTERCEPTORS HWASAN_WITH_INTERCEPTORS=1 HWASAN_DEFINITIONS)

compiler-rt/lib/hwasan/hwasan.cc

@@ -17,7 +17,6 @@
 #include "hwasan_poisoning.h"
 #include "hwasan_report.h"
 #include "hwasan_thread.h"
-#include "hwasan_thread_list.h"
 #include "sanitizer_common/sanitizer_atomic.h"
 #include "sanitizer_common/sanitizer_common.h"
 #include "sanitizer_common/sanitizer_flags.h"
@@ -175,8 +174,7 @@ static void HWAsanCheckFailed(const char *file, int line, const char *cond,
 static constexpr uptr kMemoryUsageBufferSize = 4096;
 
 static void HwasanFormatMemoryUsage(InternalScopedString &s) {
-  HwasanThreadList &thread_list = hwasanThreadList();
-  auto thread_stats = thread_list.GetThreadStats();
+  auto thread_stats = Thread::GetThreadStats();
   auto *sds = StackDepotGetStats();
   AllocatorStatCounters asc;
   GetAllocatorStats(asc);
@@ -186,7 +184,7 @@ static void HwasanFormatMemoryUsage(InternalScopedString &s) {
       " heap: %zd",
       internal_getpid(), GetRSS(), thread_stats.n_live_threads,
       thread_stats.total_stack_size,
-      thread_stats.n_live_threads * thread_list.MemoryUsedPerThread(),
+      thread_stats.n_live_threads * Thread::MemoryUsedPerThread(),
       sds->allocated, sds->n_uniq_ids, asc[AllocatorStatMapped]);
 }
 
@@ -255,12 +253,7 @@ void __hwasan_init() {
   __sanitizer_set_report_path(common_flags()->log_path);
 
   DisableCoreDumperIfNecessary();
-
   __hwasan_shadow_init();
-
-  InitThreads();
-  hwasanThreadList().CreateCurrentThread();
-
   MadviseShadow();
 
   // This may call libc -> needs initialized shadow.
@@ -275,10 +268,11 @@ void __hwasan_init() {
   InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);
 
   HwasanTSDInit();
-  HwasanTSDThreadInit();
 
   HwasanAllocatorInit();
 
+  Thread::Create();
+
 #if HWASAN_CONTAINS_UBSAN
   __ubsan::InitAsPlugin();
 #endif

compiler-rt/lib/hwasan/hwasan.h

@@ -41,10 +41,6 @@ typedef u8 tag_t;
 const unsigned kAddressTagShift = 56;
 const uptr kAddressTagMask = 0xFFUL << kAddressTagShift;
 
-// Minimal alignment of the shadow base address. Determines the space available
-// for threads and stack histories. This is an ABI constant.
-const unsigned kShadowBaseAlignment = 32;
-
 static inline tag_t GetTagFromPointer(uptr p) {
   return p >> kAddressTagShift;
 }
@@ -70,7 +66,6 @@ extern int hwasan_report_count;
 
 bool ProtectRange(uptr beg, uptr end);
 bool InitShadow();
-void InitThreads();
 void MadviseShadow();
 char *GetProcSelfMaps();
 void InitializeInterceptors();
@@ -147,7 +142,6 @@ class ScopedThreadLocalStateBackup {
 };
 
 void HwasanTSDInit();
-void HwasanTSDThreadInit();
 
 void HwasanOnDeadlySignal(int signo, void *info, void *context);
 

compiler-rt/lib/hwasan/hwasan_dynamic_shadow.cc

@@ -13,7 +13,6 @@
 ///
 //===----------------------------------------------------------------------===//
 
-#include "hwasan.h"
 #include "hwasan_dynamic_shadow.h"
 #include "hwasan_mapping.h"
 #include "sanitizer_common/sanitizer_common.h"
@@ -36,16 +35,12 @@ static void UnmapFromTo(uptr from, uptr to) {
   }
 }
 
-// Returns an address aligned to kShadowBaseAlignment, such that
-// 2**kShadowBaseAlingment on the left and shadow_size_bytes bytes on the right
-// of it are mapped no access.
+// Returns an address aligned to 8 pages, such that one page on the left and
+// shadow_size_bytes bytes on the right of it are mapped r/o.
 static uptr MapDynamicShadow(uptr shadow_size_bytes) {
   const uptr granularity = GetMmapGranularity();
-  const uptr min_alignment = granularity << kShadowScale;
-  const uptr alignment = 1ULL << kShadowBaseAlignment;
-  CHECK_GE(alignment, min_alignment);
-
-  const uptr left_padding = 1ULL << kShadowBaseAlignment;
+  const uptr alignment = granularity << kShadowScale;
+  const uptr left_padding = granularity;
   const uptr shadow_size =
       RoundUpTo(shadow_size_bytes, granularity);
   const uptr map_size = shadow_size + left_padding + alignment;

compiler-rt/lib/hwasan/hwasan_flags.inc

@@ -51,7 +51,3 @@ HWASAN_FLAG(int, heap_history_size, 1023,
           "to find bugs.")
 HWASAN_FLAG(bool, export_memory_stats, true,
             "Export up-to-date memory stats through /proc")
-HWASAN_FLAG(int, stack_history_size, 1024,
-            "The number of stack frames remembered per thread. "
-            "Affects the quality of stack-related reports, but not the ability "
-            "to find bugs.")

compiler-rt/lib/hwasan/hwasan_linux.cc

@@ -22,7 +22,6 @@
 #include "hwasan_mapping.h"
 #include "hwasan_report.h"
 #include "hwasan_thread.h"
-#include "hwasan_thread_list.h"
 
 #include <elf.h>
 #include <link.h>
@@ -38,10 +37,6 @@
 #include "sanitizer_common/sanitizer_common.h"
 #include "sanitizer_common/sanitizer_procmaps.h"
 
-#if HWASAN_WITH_INTERCEPTORS && !SANITIZER_ANDROID
-THREADLOCAL uptr __hwasan_tls;
-#endif
-
 namespace __hwasan {
 
 static void ReserveShadowMemoryRange(uptr beg, uptr end, const char *name) {
@@ -184,20 +179,6 @@ bool InitShadow() {
   return true;
 }
 
-void InitThreads() {
-  CHECK(__hwasan_shadow_memory_dynamic_address);
-  uptr guard_page_size = GetMmapGranularity();
-  uptr thread_space_start =
-      __hwasan_shadow_memory_dynamic_address - (1ULL << kShadowBaseAlignment);
-  uptr thread_space_end =
-      __hwasan_shadow_memory_dynamic_address - guard_page_size;
-  ReserveShadowMemoryRange(thread_space_start, thread_space_end - 1,
-                           "hwasan threads");
-  ProtectGap(thread_space_end,
-             __hwasan_shadow_memory_dynamic_address - thread_space_end);
-  InitThreadList(thread_space_start, thread_space_end - thread_space_start);
-}
-
 static void MadviseShadowRegion(uptr beg, uptr end) {
   uptr size = end - beg + 1;
   if (common_flags()->no_huge_pages_for_shadow)
@@ -233,33 +214,29 @@ void InstallAtExitHandler() {
 // ---------------------- TSD ---------------- {{{1
 
 extern "C" void __hwasan_thread_enter() {
-  hwasanThreadList().CreateCurrentThread();
+  Thread::Create();
 }
 
 extern "C" void __hwasan_thread_exit() {
   Thread *t = GetCurrentThread();
   // Make sure that signal handler can not see a stale current thread pointer.
   atomic_signal_fence(memory_order_seq_cst);
   if (t)
-    hwasanThreadList().ReleaseThread(t);
+    t->Destroy();
 }
 
 #if HWASAN_WITH_INTERCEPTORS
 static pthread_key_t tsd_key;
 static bool tsd_key_inited = false;
 
-void HwasanTSDThreadInit() {
-  if (tsd_key_inited)
-    CHECK_EQ(0, pthread_setspecific(tsd_key,
-                                    (void *)GetPthreadDestructorIterations()));
-}
-
 void HwasanTSDDtor(void *tsd) {
-  uptr iterations = (uptr)tsd;
-  if (iterations > 1) {
-    CHECK_EQ(0, pthread_setspecific(tsd_key, (void *)(iterations - 1)));
+  Thread *t = (Thread*)tsd;
+  if (t->destructor_iterations_ > 1) {
+    t->destructor_iterations_--;
+    CHECK_EQ(0, pthread_setspecific(tsd_key, tsd));
     return;
   }
+  t->Destroy();
   __hwasan_thread_exit();
 }
 
@@ -268,26 +245,31 @@ void HwasanTSDInit() {
   tsd_key_inited = true;
   CHECK_EQ(0, pthread_key_create(&tsd_key, HwasanTSDDtor));
 }
-#else
-void HwasanTSDInit() {}
-void HwasanTSDThreadInit() {}
-#endif
 
-#if SANITIZER_ANDROID
-uptr *GetCurrentThreadLongPtr() {
-  return (uptr *)get_android_tls_ptr();
-}
-#else
-uptr *GetCurrentThreadLongPtr() {
-  return &__hwasan_tls;
+Thread *GetCurrentThread() {
+  return (Thread *)pthread_getspecific(tsd_key);
 }
-#endif
 
+void SetCurrentThread(Thread *t) {
+  // Make sure that HwasanTSDDtor gets called at the end.
+  CHECK(tsd_key_inited);
+  // Make sure we do not reset the current Thread.
+  CHECK_EQ(0, pthread_getspecific(tsd_key));
+  pthread_setspecific(tsd_key, (void *)t);
+}
+#elif SANITIZER_ANDROID
+void HwasanTSDInit() {}
 Thread *GetCurrentThread() {
-  auto *R = (StackAllocationsRingBuffer*)GetCurrentThreadLongPtr();
-  return hwasanThreadList().GetThreadByBufferAddress((uptr)(R->Next()));
+  return (Thread*)*get_android_tls_ptr();
 }
 
+void SetCurrentThread(Thread *t) {
+  *get_android_tls_ptr() = (uptr)t;
+}
+#else
+#error unsupported configuration !HWASAN_WITH_INTERCEPTORS && !SANITIZER_ANDROID
+#endif
+
 struct AccessInfo {
   uptr addr;
   uptr size;

compiler-rt/lib/hwasan/hwasan_report.cc

@@ -16,7 +16,6 @@
 #include "hwasan_allocator.h"
 #include "hwasan_mapping.h"
 #include "hwasan_thread.h"
-#include "hwasan_thread_list.h"
 #include "sanitizer_common/sanitizer_allocator_internal.h"
 #include "sanitizer_common/sanitizer_common.h"
 #include "sanitizer_common/sanitizer_flags.h"
@@ -36,31 +35,6 @@ static StackTrace GetStackTraceFromId(u32 id) {
   return res;
 }
 
-// A RAII object that holds a copy of the current thread stack ring buffer.
-// The actual stack buffer may change while we are iterating over it (for
-// example, Printf may call syslog() which can itself be built with hwasan).
-class SavedStackAllocations {
- public:
-  SavedStackAllocations(StackAllocationsRingBuffer *rb) {
-    uptr size = rb->size() * sizeof(uptr);
-    void *storage =
-        MmapAlignedOrDieOnFatalError(size, size * 2, "saved stack allocations");
-    new (&rb_) StackAllocationsRingBuffer(*rb, storage);
-  }
-
-  ~SavedStackAllocations() {
-    StackAllocationsRingBuffer *rb = get();
-    UnmapOrDie(rb->StartOfStorage(), rb->size() * sizeof(uptr));
-  }
-
-  StackAllocationsRingBuffer *get() {
-    return (StackAllocationsRingBuffer *)&rb_;
-  }
-
- private:
-  uptr rb_;
-};
-
 class Decorator: public __sanitizer::SanitizerCommonDecorator {
  public:
   Decorator() : SanitizerCommonDecorator() { }
@@ -89,9 +63,7 @@ uptr FindHeapAllocation(HeapAllocationsRingBuffer *rb,
   return 0;
 }
 
-void PrintAddressDescription(
-    uptr tagged_addr, uptr access_size,
-    StackAllocationsRingBuffer *current_stack_allocations) {
+void PrintAddressDescription(uptr tagged_addr, uptr access_size) {
   Decorator d;
   int num_descriptions_printed = 0;
   uptr untagged_addr = UntagAddr(tagged_addr);
@@ -137,7 +109,7 @@ void PrintAddressDescription(
     }
   }
 
-  hwasanThreadList().VisitAllLiveThreads([&](Thread *t) {
+  Thread::VisitAllLiveThreads([&](Thread *t) {
     // Scan all threads' ring buffers to find if it's a heap-use-after-free.
     HeapAllocationRecord har;
     if (uptr D = FindHeapAllocation(t->heap_allocations(), tagged_addr, &har)) {
@@ -173,25 +145,6 @@ void PrintAddressDescription(
       Printf("%s", d.Default());
       t->Announce();
 
-      // Temporary report section, needs to be improved.
-      Printf("Previosly allocated frames:\n");
-      auto *sa = (t == GetCurrentThread() && current_stack_allocations)
-                     ? current_stack_allocations
-                     : t->stack_allocations();
-      uptr frames = Min((uptr)flags()->stack_history_size, sa->size());
-      for (uptr i = 0; i < frames; i++) {
-        uptr record = (*sa)[i];
-        if (!record)
-          break;
-        uptr sp = (record >> 48) << 4;
-        uptr pc_mask = (1ULL << 48) - 1;
-        uptr pc = record & pc_mask;
-        uptr fixed_pc = StackTrace::GetNextInstructionPc(pc);
-        StackTrace stack(&fixed_pc, 1);
-        Printf("record: %p pc: %p sp: %p", record, pc, sp);
-        stack.Print();
-      }
-
       num_descriptions_printed++;
     }
   });
@@ -217,16 +170,13 @@ void ReportStats() {}
 void ReportInvalidAccessInsideAddressRange(const char *what, const void *start,
                                            uptr size, uptr offset) {
   ScopedErrorReportLock l;
-  SavedStackAllocations current_stack_allocations(
-      GetCurrentThread()->stack_allocations());
 
   Decorator d;
   Printf("%s", d.Warning());
   Printf("%sTag mismatch in %s%s%s at offset %zu inside [%p, %zu)%s\n",
          d.Warning(), d.Name(), what, d.Warning(), offset, start, size,
          d.Default());
-  PrintAddressDescription((uptr)start + offset, 1,
-                          current_stack_allocations.get());
+  PrintAddressDescription((uptr)start + offset, 1);
   // if (__sanitizer::Verbosity())
   //   DescribeMemoryRange(start, size);
 }
@@ -274,7 +224,7 @@ void ReportInvalidFree(StackTrace *stack, uptr tagged_addr) {
 
   stack->Print();
 
-  PrintAddressDescription(tagged_addr, 0, nullptr);
+  PrintAddressDescription(tagged_addr, 0);
 
   PrintTagsAroundAddr(tag_ptr);
 
@@ -285,8 +235,6 @@ void ReportInvalidFree(StackTrace *stack, uptr tagged_addr) {
 void ReportTagMismatch(StackTrace *stack, uptr tagged_addr, uptr access_size,
                        bool is_store) {
   ScopedErrorReportLock l;
-  SavedStackAllocations current_stack_allocations(
-      GetCurrentThread()->stack_allocations());
 
   Decorator d;
   Printf("%s", d.Error());
@@ -310,8 +258,7 @@ void ReportTagMismatch(StackTrace *stack, uptr tagged_addr, uptr access_size,
 
   stack->Print();
 
-  PrintAddressDescription(tagged_addr, access_size,
-                          current_stack_allocations.get());
+  PrintAddressDescription(tagged_addr, access_size);
   t->Announce();
 
   PrintTagsAroundAddr(tag_ptr);