Merge "Fix global finding logic." (d88210b6) · Commits · e / os / android_system_core

libunwindstack/Global.cpp

+18 −20

Original line number	Diff line number	Diff line
		@@ -70,12 +70,16 @@ void Global::FindAndReadVariable(Maps* maps, const char* var_str) {
		// This also works:
		// f0000-f2000 0 r-- /system/lib/libc.so
		// f2000-f3000 2000 rw- /system/lib/libc.so
		MapInfo* map_start = nullptr;
		// It is also possible to see empty maps after the read-only like so:
		// f0000-f1000 0 r-- /system/lib/libc.so
		// f1000-f2000 0 ---
		// f2000-f3000 1000 r-x /system/lib/libc.so
		// f3000-f4000 2000 rw- /system/lib/libc.so
		MapInfo* map_zero = nullptr;
		for (const auto& info : *maps) {
		if (map_start != nullptr && map_start->name == info->name) {
		if (info->offset != 0 &&
		(info->flags & (PROT_READ \| PROT_WRITE)) == (PROT_READ \| PROT_WRITE)) {
		Elf* elf = map_start->GetElf(memory_, arch());
		if (info->offset != 0 && (info->flags & (PROT_READ \| PROT_WRITE)) == (PROT_READ \| PROT_WRITE) &&
		map_zero != nullptr && Searchable(info->name) && info->name == map_zero->name) {
		Elf* elf = map_zero->GetElf(memory_, arch());
		uint64_t ptr;
		if (elf->GetGlobalVariableOffset(variable, &ptr) && ptr != 0) {
		uint64_t offset_end = info->offset + info->end - info->start;
		@@ -86,14 +90,8 @@ void Global::FindAndReadVariable(Maps* maps, const char* var_str) {
		}
		}
		}
		map_start = nullptr;
		}
		} else {
		map_start = nullptr;
		}
		if (map_start == nullptr && (info->flags & PROT_READ) && info->offset == 0 &&
		Searchable(info->name)) {
		map_start = info.get();
		} else if (info->offset == 0 && !info->name.empty()) {
		map_zero = info.get();
		}
		}
		}

libunwindstack/tests/DexFilesTest.cpp

+26 −1

Original line number	Diff line number	Diff line
		@@ -64,7 +64,11 @@ class DexFilesTest : public ::testing::Test {
		"f000-11000 r--p 00000000 00:00 0 /fake/elf3\n"
		"100000-110000 rw-p 00f1000 00:00 0 /fake/elf3\n"
		"200000-210000 rw-p 0002000 00:00 0 /fake/elf3\n"
		"300000-400000 rw-p 0003000 00:00 0 /fake/elf3\n"));
		"300000-400000 rw-p 0003000 00:00 0 /fake/elf3\n"
		"500000-501000 r--p 0000000 00:00 0 /fake/elf4\n"
		"501000-502000 ---p 0000000 00:00 0\n"
		"503000-510000 rw-p 0003000 00:00 0 /fake/elf4\n"
		"510000-520000 rw-p 0010000 00:00 0 /fake/elf4\n"));
		ASSERT_TRUE(maps_->Parse());

		// Global variable in a section that is not readable.
		@@ -81,6 +85,11 @@ class DexFilesTest : public ::testing::Test {
		map_info = maps_->Get(kMapGlobal);
		ASSERT_TRUE(map_info != nullptr);
		CreateFakeElf(map_info, 0xf1800, 0xf1000, 0xf1000, 0x10000);

		// Global variable set in this map, but there is an empty map before rw map.
		map_info = maps_->Get(kMapGlobalAfterEmpty);
		ASSERT_TRUE(map_info != nullptr);
		CreateFakeElf(map_info, 0x3800, 0x3000, 0x3000, 0xd000);
		}

		void SetUp() override {
		@@ -102,6 +111,8 @@ class DexFilesTest : public ::testing::Test {
		static constexpr size_t kMapGlobalRw = 6;
		static constexpr size_t kMapDexFileEntries = 7;
		static constexpr size_t kMapDexFiles = 8;
		static constexpr size_t kMapGlobalAfterEmpty = 9;
		static constexpr size_t kMapDexFilesAfterEmpty = 12;

		std::shared_ptr<Memory> process_memory_;
		MemoryFake* memory_;
		@@ -328,4 +339,18 @@ TEST_F(DexFilesTest, get_method_information_global_skip_zero_64) {
		EXPECT_EQ(0x123U, method_offset);
		}

		TEST_F(DexFilesTest, get_method_information_with_empty_map) {
		std::string method_name = "nothing";
		uint64_t method_offset = 0x124;
		MapInfo* info = maps_->Get(kMapDexFilesAfterEmpty);

		WriteDescriptor32(0x503800, 0x506000);
		WriteEntry32(0x506000, 0, 0, 0x510000);
		WriteDex(0x510000);

		dex_files_->GetMethodInformation(maps_.get(), info, 0x510100, &method_name, &method_offset);
		EXPECT_EQ("Main.<init>", method_name);
		EXPECT_EQ(0U, method_offset);
		}

		} // namespace unwindstack