[sanitizer] fix LargeMmapAllocator::GetBlockBegin

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@170434 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 17 insertions, 19 deletions

diff --git a/lib/sanitizer_common/sanitizer_allocator.h b/lib/sanitizer_common/sanitizer_allocator.h
index b10957ab..7a97cc9f 100644
--- a/lib/sanitizer_common/sanitizer_allocator.h
+++ b/lib/sanitizer_common/sanitizer_allocator.h
@@ -674,17 +674,11 @@ class LargeMmapAllocator {
   }
 
   bool PointerIsMine(void *p) {
-    // Fast check.
-    if ((reinterpret_cast<uptr>(p) & (page_size_ - 1))) return false;
-    SpinMutexLock l(&mutex_);
-    for (Header *l = list_; l; l = l->next) {
-      if (GetUser(l) == p) return true;
-    }
-    return false;
+    return GetBlockBegin(p) != 0;
   }
 
   uptr GetActuallyAllocatedSize(void *p) {
-    return RoundUpMapSize(GetHeader(p)->size) - page_size_;
+    return RoundUpTo(GetHeader(p)->size, page_size_);
   }
 
   // At least page_size_/2 metadata bytes is available.
@@ -692,12 +686,12 @@ class LargeMmapAllocator {
     return GetHeader(p) + 1;
   }
 
-  void *GetBlockBegin(void *p) {
+  void *GetBlockBegin(void *ptr) {
+    uptr p = reinterpret_cast<uptr>(ptr);
     SpinMutexLock l(&mutex_);
     for (Header *l = list_; l; l = l->next) {
-      void *b = GetUser(l);
-      if (p >= b && p < (u8*)b + l->size)
-        return b;
+      if (p >= l->map_beg && p < l->map_beg + l->map_size)
+        return GetUser(l);
     }
     return 0;
   }
diff --git a/lib/sanitizer_common/tests/sanitizer_allocator_test.cc b/lib/sanitizer_common/tests/sanitizer_allocator_test.cc
index 04269eda..bb239f9d 100644
--- a/lib/sanitizer_common/tests/sanitizer_allocator_test.cc
+++ b/lib/sanitizer_common/tests/sanitizer_allocator_test.cc
@@ -106,6 +106,8 @@ void TestSizeClassAllocator() {
         CHECK_EQ(x, a->GetBlockBegin(x));
         CHECK_EQ(x, a->GetBlockBegin(x + size - 1));
         CHECK(a->PointerIsMine(x));
+        CHECK(a->PointerIsMine(x + size - 1));
+        CHECK(a->PointerIsMine(x + size / 2));
         CHECK_GE(a->GetActuallyAllocatedSize(x), size);
         uptr class_id = a->GetSizeClass(x);
         CHECK_EQ(class_id, Allocator::SizeClassMapT::ClassID(size));
@@ -265,16 +267,16 @@ TEST(SanitizerCommon, LargeMmapAllocator) {
   a.Init();
 
   static const int kNumAllocs = 100;
-  void *allocated[kNumAllocs];
+  char *allocated[kNumAllocs];
   static const uptr size = 1000;
   // Allocate some.
   for (int i = 0; i < kNumAllocs; i++) {
-    allocated[i] = a.Allocate(size, 1);
+    allocated[i] = (char *)a.Allocate(size, 1);
   }
   // Deallocate all.
   CHECK_GT(a.TotalMemoryUsed(), size * kNumAllocs);
   for (int i = 0; i < kNumAllocs; i++) {
-    void *p = allocated[i];
+    char *p = allocated[i];
     CHECK(a.PointerIsMine(p));
     a.Deallocate(p);
   }
@@ -283,7 +285,7 @@ TEST(SanitizerCommon, LargeMmapAllocator) {
 
   // Allocate some more, also add metadata.
   for (int i = 0; i < kNumAllocs; i++) {
-    void *x = a.Allocate(size, 1);
+    char *x = (char *)a.Allocate(size, 1);
     CHECK_GE(a.GetActuallyAllocatedSize(x), size);
     uptr *meta = reinterpret_cast<uptr*>(a.GetMetaData(x));
     *meta = i;
@@ -293,7 +295,7 @@ TEST(SanitizerCommon, LargeMmapAllocator) {
   // Deallocate all in reverse order.
   for (int i = 0; i < kNumAllocs; i++) {
     int idx = kNumAllocs - i - 1;
-    void *p = allocated[idx];
+    char *p = allocated[idx];
     uptr *meta = reinterpret_cast<uptr*>(a.GetMetaData(p));
     CHECK_EQ(*meta, idx);
     CHECK(a.PointerIsMine(p));
@@ -304,9 +306,11 @@ TEST(SanitizerCommon, LargeMmapAllocator) {
   for (uptr alignment = 8; alignment <= max_alignment; alignment *= 2) {
     for (int i = 0; i < kNumAllocs; i++) {
       uptr size = ((i % 10) + 1) * 4096;
-      allocated[i] = a.Allocate(size, alignment);
+      char *p = allocated[i] = (char *)a.Allocate(size, alignment);
+      CHECK_EQ(p, a.GetBlockBegin(p));
+      CHECK_EQ(p, a.GetBlockBegin(p + size - 1));
+      CHECK_EQ(p, a.GetBlockBegin(p + size / 2));
       CHECK_EQ(0, (uptr)allocated[i] % alignment);
-      char *p = (char*)allocated[i];
       p[0] = p[size - 1] = 0;
     }
     for (int i = 0; i < kNumAllocs; i++) {