Merge "Fix which maps to search for globals."

libunwindstack/Android.bp

@@ -58,6 +58,7 @@ cc_library {
         "Elf.cpp",
         "ElfInterface.cpp",
         "ElfInterfaceArm.cpp",
+        "Global.cpp",
         "JitDebug.cpp",
         "Log.cpp",
         "MapInfo.cpp",

libunwindstack/DexFiles.cpp

@@ -43,10 +43,10 @@ struct DEXFileEntry64 {
   uint64_t dex_file;
 };
 
-DexFiles::DexFiles(std::shared_ptr<Memory>& memory) : memory_(memory) {}
+DexFiles::DexFiles(std::shared_ptr<Memory>& memory) : Global(memory) {}
 
 DexFiles::DexFiles(std::shared_ptr<Memory>& memory, std::vector<std::string>& search_libs)
-    : memory_(memory), search_libs_(search_libs) {}
+    : Global(memory, search_libs) {}
 
 DexFiles::~DexFiles() {
   for (auto& entry : files_) {
@@ -117,6 +117,11 @@ bool DexFiles::ReadEntry64() {
   return true;
 }
 
+bool DexFiles::ReadVariableData(uint64_t ptr_offset) {
+  entry_addr_ = (this->*read_entry_ptr_func_)(ptr_offset);
+  return entry_addr_ != 0;
+}
+
 void DexFiles::Init(Maps* maps) {
   if (initialized_) {
     return;
@@ -124,36 +129,7 @@ void DexFiles::Init(Maps* maps) {
   initialized_ = true;
   entry_addr_ = 0;
 
-  const std::string dex_debug_name("__dex_debug_descriptor");
+  FindAndReadVariable(maps, "__dex_debug_descriptor");
-  for (MapInfo* info : *maps) {
-    if (!(info->flags & PROT_READ) || info->offset != 0) {
-      continue;
-    }
-
-    if (!search_libs_.empty()) {
-      bool found = false;
-      const char* lib = basename(info->name.c_str());
-      for (const std::string& name : search_libs_) {
-        if (name == lib) {
-          found = true;
-          break;
-        }
-      }
-      if (!found) {
-        continue;
-      }
-    }
-
-    Elf* elf = info->GetElf(memory_, true);
-    uint64_t ptr;
-    // Find first non-empty list (libart might be loaded multiple times).
-    if (elf->GetGlobalVariable(dex_debug_name, &ptr) && ptr != 0) {
-      entry_addr_ = (this->*read_entry_ptr_func_)(ptr + info->start);
-      if (entry_addr_ != 0) {
-        break;
-      }
-    }
-  }
 }
 
 DexFile* DexFiles::GetDexFile(uint64_t dex_file_offset, MapInfo* info) {

libunwindstack/Global.cpp

@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdint.h>
+#include <sys/mman.h>
+
+#include <string>
+#include <vector>
+
+#include <unwindstack/Global.h>
+#include <unwindstack/MapInfo.h>
+#include <unwindstack/Maps.h>
+#include <unwindstack/Memory.h>
+
+namespace unwindstack {
+
+Global::Global(std::shared_ptr<Memory>& memory) : memory_(memory) {}
+Global::Global(std::shared_ptr<Memory>& memory, std::vector<std::string>& search_libs)
+    : memory_(memory), search_libs_(search_libs) {}
+
+uint64_t Global::GetVariableOffset(MapInfo* info, const std::string& variable) {
+  if (!search_libs_.empty()) {
+    bool found = false;
+    const char* lib = basename(info->name.c_str());
+    for (const std::string& name : search_libs_) {
+      if (name == lib) {
+        found = true;
+        break;
+      }
+    }
+    if (!found) {
+      return 0;
+    }
+  }
+
+  Elf* elf = info->GetElf(memory_, true);
+  uint64_t ptr;
+  // Find first non-empty list (libraries might be loaded multiple times).
+  if (elf->GetGlobalVariable(variable, &ptr) && ptr != 0) {
+    return ptr + info->start;
+  }
+  return 0;
+}
+
+void Global::FindAndReadVariable(Maps* maps, const char* var_str) {
+  std::string variable(var_str);
+  // When looking for global variables, do not arbitrarily search every
+  // readable map. Instead look for a specific pattern that must exist.
+  // The pattern should be a readable map, followed by a read-write
+  // map with a non-zero offset.
+  // For example:
+  //   f0000-f1000 0 r-- /system/lib/libc.so
+  //   f1000-f2000 1000 r-x /system/lib/libc.so
+  //   f2000-f3000 2000 rw- /system/lib/libc.so
+  // This also works:
+  //   f0000-f2000 0 r-- /system/lib/libc.so
+  //   f2000-f3000 2000 rw- /system/lib/libc.so
+  MapInfo* map_start = nullptr;
+  for (MapInfo* info : *maps) {
+    if (map_start != nullptr) {
+      if (map_start->name == info->name) {
+        if (info->offset != 0 &&
+            (info->flags & (PROT_READ | PROT_WRITE)) == (PROT_READ | PROT_WRITE)) {
+          uint64_t ptr = GetVariableOffset(map_start, variable);
+          if (ptr != 0 && ReadVariableData(ptr)) {
+            break;
+          } else {
+            // Failed to find the global variable, do not bother trying again.
+            map_start = nullptr;
+          }
+        }
+      } else {
+        map_start = nullptr;
+      }
+    }
+    if (map_start == nullptr && (info->flags & PROT_READ) && info->offset == 0 &&
+        !info->name.empty()) {
+      map_start = info;
+    }
+  }
+}
+
+}  // namespace unwindstack

libunwindstack/JitDebug.cpp

@@ -69,10 +69,10 @@ struct JITDescriptor64 {
   uint64_t first_entry;
 };
 
-JitDebug::JitDebug(std::shared_ptr<Memory>& memory) : memory_(memory) {}
+JitDebug::JitDebug(std::shared_ptr<Memory>& memory) : Global(memory) {}
 
 JitDebug::JitDebug(std::shared_ptr<Memory>& memory, std::vector<std::string>& search_libs)
-    : memory_(memory), search_libs_(search_libs) {}
+    : Global(memory, search_libs) {}
 
 JitDebug::~JitDebug() {
   for (auto* elf : elf_list_) {
@@ -165,6 +165,11 @@ void JitDebug::SetArch(ArchEnum arch) {
   }
 }
 
+bool JitDebug::ReadVariableData(uint64_t ptr) {
+  entry_addr_ = (this->*read_descriptor_func_)(ptr);
+  return entry_addr_ != 0;
+}
+
 void JitDebug::Init(Maps* maps) {
   if (initialized_) {
     return;
@@ -172,36 +177,7 @@ void JitDebug::Init(Maps* maps) {
   // Regardless of what happens below, consider the init finished.
   initialized_ = true;
 
-  const std::string descriptor_name("__jit_debug_descriptor");
+  FindAndReadVariable(maps, "__jit_debug_descriptor");
-  for (MapInfo* info : *maps) {
-    if (!(info->flags & PROT_READ) || info->offset != 0) {
-      continue;
-    }
-
-    if (!search_libs_.empty()) {
-      bool found = false;
-      const char* lib = basename(info->name.c_str());
-      for (std::string& name : search_libs_) {
-        if (strcmp(name.c_str(), lib) == 0) {
-          found = true;
-          break;
-        }
-      }
-      if (!found) {
-        continue;
-      }
-    }
-
-    Elf* elf = info->GetElf(memory_, true);
-    uint64_t descriptor_addr;
-    // Find first non-empty entry (libart might be loaded multiple times).
-    if (elf->GetGlobalVariable(descriptor_name, &descriptor_addr) && descriptor_addr != 0) {
-      entry_addr_ = (this->*read_descriptor_func_)(descriptor_addr + info->start);
-      if (entry_addr_ != 0) {
-        break;
-      }
-    }
-  }
 }
 
 Elf* JitDebug::GetElf(Maps* maps, uint64_t pc) {

libunwindstack/include/unwindstack/DexFiles.h

@@ -25,16 +25,18 @@
 #include <unordered_map>
 #include <vector>
 
+#include <unwindstack/Global.h>
+#include <unwindstack/Memory.h>
+
 namespace unwindstack {
 
 // Forward declarations.
 class DexFile;
 class Maps;
 struct MapInfo;
-class Memory;
 enum ArchEnum : uint8_t;
 
-class DexFiles {
+class DexFiles : public Global {
  public:
   explicit DexFiles(std::shared_ptr<Memory>& memory);
   DexFiles(std::shared_ptr<Memory>& memory, std::vector<std::string>& search_libs);
@@ -60,8 +62,7 @@ class DexFiles {
 
   bool ReadEntry64();
 
-  std::shared_ptr<Memory> memory_;
+  bool ReadVariableData(uint64_t ptr_offset) override;
-  std::vector<std::string> search_libs_;
 
   std::mutex lock_;
   bool initialized_ = false;

libunwindstack/include/unwindstack/Global.h

@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _LIBUNWINDSTACK_GLOBAL_H
+#define _LIBUNWINDSTACK_GLOBAL_H
+
+#include <stdint.h>
+
+#include <memory>
+#include <mutex>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+#include <unwindstack/Memory.h>
+
+namespace unwindstack {
+
+// Forward declarations.
+class Maps;
+struct MapInfo;
+
+class Global {
+ public:
+  explicit Global(std::shared_ptr<Memory>& memory);
+  Global(std::shared_ptr<Memory>& memory, std::vector<std::string>& search_libs);
+  virtual ~Global() = default;
+
+ protected:
+  uint64_t GetVariableOffset(MapInfo* info, const std::string& variable);
+  void FindAndReadVariable(Maps* maps, const char* variable);
+
+  virtual bool ReadVariableData(uint64_t offset) = 0;
+
+  std::shared_ptr<Memory> memory_;
+  std::vector<std::string> search_libs_;
+};
+
+}  // namespace unwindstack
+
+#endif  // _LIBUNWINDSTACK_GLOBAL_H

libunwindstack/include/unwindstack/JitDebug.h

@@ -24,15 +24,17 @@
 #include <string>
 #include <vector>
 
+#include <unwindstack/Global.h>
+#include <unwindstack/Memory.h>
+
 namespace unwindstack {
 
 // Forward declarations.
 class Elf;
 class Maps;
-class Memory;
 enum ArchEnum : uint8_t;
 
-class JitDebug {
+class JitDebug : public Global {
  public:
   explicit JitDebug(std::shared_ptr<Memory>& memory);
   JitDebug(std::shared_ptr<Memory>& memory, std::vector<std::string>& search_libs);
@@ -45,11 +47,9 @@ class JitDebug {
  private:
   void Init(Maps* maps);
 
-  std::shared_ptr<Memory> memory_;
   uint64_t entry_addr_ = 0;
   bool initialized_ = false;
   std::vector<Elf*> elf_list_;
-  std::vector<std::string> search_libs_;
 
   std::mutex lock_;
 
@@ -62,6 +62,8 @@ class JitDebug {
   uint64_t ReadEntry32Pack(uint64_t* start, uint64_t* size);
   uint64_t ReadEntry32Pad(uint64_t* start, uint64_t* size);
   uint64_t ReadEntry64(uint64_t* start, uint64_t* size);
+
+  bool ReadVariableData(uint64_t ptr_offset) override;
 };
 
 }  // namespace unwindstack

libunwindstack/tests/DexFilesTest.cpp

@@ -44,15 +44,15 @@ class DexFilesTest : public ::testing::Test {
     dex_files_->SetArch(ARCH_ARM);
 
     maps_.reset(
-        new BufferMaps("1000-4000 ---s 00000000 00:00 0\n"
+        new BufferMaps("1000-4000 ---s 00000000 00:00 0 /fake/elf\n"
-                       "4000-6000 r--s 00000000 00:00 0\n"
+                       "4000-6000 r--s 00000000 00:00 0 /fake/elf\n"
-                       "6000-8000 -wxs 00000000 00:00 0\n"
+                       "6000-8000 -wxs 00000000 00:00 0 /fake/elf\n"
-                       "a000-c000 r--p 00000000 00:00 0\n"
+                       "a000-c000 r--p 00000000 00:00 0 /fake/elf2\n"
-                       "c000-f000 rw-p 00000000 00:00 0\n"
+                       "c000-f000 rw-p 00001000 00:00 0 /fake/elf2\n"
-                       "f000-11000 r--p 00000000 00:00 0\n"
+                       "f000-11000 r--p 00000000 00:00 0 /fake/elf3\n"
-                       "100000-110000 rw-p 0000000 00:00 0\n"
+                       "100000-110000 rw-p 0001000 00:00 0 /fake/elf3\n"
-                       "200000-210000 rw-p 0000000 00:00 0\n"
+                       "200000-210000 rw-p 0002000 00:00 0 /fake/elf3\n"
-                       "300000-400000 rw-p 0000000 00:00 0\n"));
+                       "300000-400000 rw-p 0003000 00:00 0 /fake/elf3\n"));
     ASSERT_TRUE(maps_->Parse());
 
     // Global variable in a section that is not readable.
@@ -96,8 +96,9 @@ class DexFilesTest : public ::testing::Test {
   void WriteDex(uint64_t dex_file);
 
   static constexpr size_t kMapGlobalNonReadable = 2;
-  static constexpr size_t kMapGlobalSetToZero = 4;
+  static constexpr size_t kMapGlobalSetToZero = 3;
   static constexpr size_t kMapGlobal = 5;
+  static constexpr size_t kMapGlobalRw = 6;
   static constexpr size_t kMapDexFileEntries = 7;
   static constexpr size_t kMapDexFiles = 8;
 
@@ -256,6 +257,9 @@ TEST_F(DexFilesTest, get_method_information_search_libs) {
   map_info->name = "/system/lib/libart.so";
   dex_files_.reset(new DexFiles(process_memory_, libs));
   dex_files_->SetArch(ARCH_ARM);
+  // Set the rw map to the same name or this will not scan this entry.
+  map_info = maps_->Get(kMapGlobalRw);
+  map_info->name = "/system/lib/libart.so";
   // Make sure that clearing out copy of the libs doesn't affect the
   // DexFiles object.
   libs.clear();
@@ -271,7 +275,7 @@ TEST_F(DexFilesTest, get_method_information_global_skip_zero_32) {
   MapInfo* info = maps_->Get(kMapDexFiles);
 
   // First global variable found, but value is zero.
-  WriteDescriptor32(0xc800, 0);
+  WriteDescriptor32(0xa800, 0);
 
   WriteDescriptor32(0xf800, 0x200000);
   WriteEntry32(0x200000, 0, 0, 0x300000);
@@ -286,7 +290,7 @@ TEST_F(DexFilesTest, get_method_information_global_skip_zero_32) {
   dex_files_->SetArch(ARCH_ARM);
   method_name = "fail";
   method_offset = 0x123;
-  WriteDescriptor32(0xc800, 0x100000);
+  WriteDescriptor32(0xa800, 0x100000);
   dex_files_->GetMethodInformation(maps_.get(), info, 0x300100, &method_name, &method_offset);
   EXPECT_EQ("fail", method_name);
   EXPECT_EQ(0x123U, method_offset);
@@ -298,7 +302,7 @@ TEST_F(DexFilesTest, get_method_information_global_skip_zero_64) {
   MapInfo* info = maps_->Get(kMapDexFiles);
 
   // First global variable found, but value is zero.
-  WriteDescriptor64(0xc800, 0);
+  WriteDescriptor64(0xa800, 0);
 
   WriteDescriptor64(0xf800, 0x200000);
   WriteEntry64(0x200000, 0, 0, 0x300000);
@@ -314,7 +318,7 @@ TEST_F(DexFilesTest, get_method_information_global_skip_zero_64) {
   dex_files_->SetArch(ARCH_ARM64);
   method_name = "fail";
   method_offset = 0x123;
-  WriteDescriptor64(0xc800, 0x100000);
+  WriteDescriptor64(0xa800, 0x100000);
   dex_files_->GetMethodInformation(maps_.get(), info, 0x300100, &method_name, &method_offset);
   EXPECT_EQ("fail", method_name);
   EXPECT_EQ(0x123U, method_offset);

libunwindstack/tests/JitDebugTest.cpp

@@ -43,15 +43,16 @@ class JitDebugTest : public ::testing::Test {
     jit_debug_->SetArch(ARCH_ARM);
 
     maps_.reset(
-        new BufferMaps("1000-4000 ---s 00000000 00:00 0\n"
+        new BufferMaps("1000-4000 ---s 00000000 00:00 0 /fake/elf1\n"
-                       "4000-6000 r--s 00000000 00:00 0\n"
+                       "4000-6000 r--s 00000000 00:00 0 /fake/elf1\n"
-                       "6000-8000 -wxs 00000000 00:00 0\n"
+                       "6000-8000 -wxs 00000000 00:00 0 /fake/elf1\n"
-                       "a000-c000 --xp 00000000 00:00 0\n"
+                       "a000-c000 --xp 00000000 00:00 0 /fake/elf2\n"
-                       "c000-f000 rw-p 00000000 00:00 0\n"
+                       "c000-f000 rw-p 00001000 00:00 0 /fake/elf2\n"
-                       "f000-11000 r--p 00000000 00:00 0\n"
+                       "f000-11000 r--p 00000000 00:00 0 /fake/elf3\n"
-                       "12000-14000 r--p 00000000 00:00 0\n"
+                       "11000-12000 rw-p 00001000 00:00 0 /fake/elf3\n"
-                       "100000-110000 rw-p 0000000 00:00 0\n"
+                       "12000-14000 r--p 00000000 00:00 0 /fake/elf4\n"
-                       "200000-210000 rw-p 0000000 00:00 0\n"));
+                       "100000-110000 rw-p 0001000 00:00 0 /fake/elf4\n"
+                       "200000-210000 rw-p 0002000 00:00 0 /fake/elf4\n"));
     ASSERT_TRUE(maps_->Parse());
 
     MapInfo* map_info = maps_->Get(3);
@@ -74,7 +75,7 @@ class JitDebugTest : public ::testing::Test {
     interface->FakeSetGlobalVariable("__jit_debug_descriptor", 0x800);
     map_info->elf.reset(elf);
 
-    map_info = maps_->Get(6);
+    map_info = maps_->Get(7);
     ASSERT_TRUE(map_info != nullptr);
     memory = new MemoryFake;
     elf = new ElfFake(memory);
@@ -397,6 +398,8 @@ TEST_F(JitDebugTest, get_elf_search_libs) {
   // Change the name of the map that includes the value and verify this works.
   MapInfo* map_info = maps_->Get(5);
   map_info->name = "/system/lib/libart.so";
+  map_info = maps_->Get(6);
+  map_info->name = "/system/lib/libart.so";
   jit_debug_.reset(new JitDebug(process_memory_, libs));
   // Make sure that clearing our copy of the libs doesn't affect the
   // JitDebug object.

libunwindstack/tests/files/offline/art_quick_osr_stub_arm/maps.txt

@@ -1,3 +1,4 @@
 d0250000-d2600000 r-xp 0 00:00 0 <anonymous:d0250000>
 e466e000-e4ae8000 r-xp 0 00:00 0 libart.so
+e4ae8000-e4ae9000 rw-p 1000 00:00 0 libart.so
 e7d91000-e7e31000 r-xp 0 00:00 0 libc.so

libunwindstack/tests/files/offline/jit_debug_arm/maps.txt

@@ -2,7 +2,9 @@ ab0d3000-ab0d8000 r-xp 0 00:00 0   dalvikvm32
 dfe4e000-dfe7b000 r-xp 0 00:00 0   libarttestd.so
 e0447000-e0448000 r-xp 2000 00:00 0   137-cfi.odex
 e2796000-e4796000 r-xp 0 00:00 0   anonymous:e2796000
-e648e000-e690f000 r-xp 00000000 00:00 0  libart.so
+e648e000-e690f000 r-xp 0 00:00 0  libart.so
+e690f000-e6910000 rw-p 1000 00:00 0  libart.so
 ed306000-ed801000 r-xp 0 00:00 0   libartd.so
+ed801000-ed802000 rw-p 1000 00:00 0   libartd.so
 eda88000-edb23000 r-xp 0 00:00 0   libc.so
 ede4e000-ede50000 r-xp 0 00:00 0   anonymous:ede4e000

libunwindstack/tests/files/offline/jit_debug_x86/maps.txt

@@ -3,4 +3,5 @@ eb833000-eb8cc000 r-xp 0 00:00 0   libarttestd.so
 ec606000-ec607000 r-xp 2000 00:00 0   137-cfi.odex
 ee74c000-f074c000 r-xp 0 00:00 0   anonymous:ee74c000
 f6be1000-f732b000 r-xp 0 00:00 0   libartd.so
+f732b000-f732c000 rw-p 1000 00:00 0   libartd.so
 f734b000-f74fc000 r-xp 0 00:00 0   libc.so