Fix dangling pointer issue in LocalUpdatbleMaps
Libunwindstack would remove duplicated items and update the `prev_map`
during reparsing `/proc/self/maps`. But we leave `prev_real_map`
pointing toward a MapInfo that will be deleted soon. It will cause a
dangling pointer issue.
Add new tests to cover this dangling pointer issue.
Bug: 155511785
Test: libunwindstack_test
Change-Id: I62e1b97bcb73f07e9349671f0b758f5ec9de16c0
diff --git a/libunwindstack/tests/LocalUpdatableMapsTest.cpp b/libunwindstack/tests/LocalUpdatableMapsTest.cpp
index b816b9a..99afb0b 100644
--- a/libunwindstack/tests/LocalUpdatableMapsTest.cpp
+++ b/libunwindstack/tests/LocalUpdatableMapsTest.cpp
@@ -271,4 +271,103 @@
EXPECT_TRUE(map_info->name.empty());
}
+TEST_F(LocalUpdatableMapsTest, add_map_prev_name_updated) {
+ TemporaryFile tf;
+ ASSERT_TRUE(
+ android::base::WriteStringToFile("3000-4000 rwxp 00000 00:00 0\n"
+ "8000-9000 r-xp 00000 00:00 0\n"
+ "9000-a000 r-xp 00000 00:00 0\n",
+ tf.path));
+
+ maps_.TestSetMapsFile(tf.path);
+ ASSERT_TRUE(maps_.Reparse());
+ ASSERT_EQ(3U, maps_.Total());
+
+ MapInfo* map_info = maps_.Get(2);
+ ASSERT_TRUE(map_info != nullptr);
+ EXPECT_EQ(0x9000U, map_info->start);
+ EXPECT_EQ(0xA000U, map_info->end);
+ EXPECT_EQ(0U, map_info->offset);
+ EXPECT_EQ(PROT_READ | PROT_EXEC, map_info->flags);
+ EXPECT_TRUE(map_info->name.empty());
+ EXPECT_EQ(maps_.Get(1), map_info->prev_map);
+}
+
+TEST_F(LocalUpdatableMapsTest, add_map_prev_real_name_updated) {
+ TemporaryFile tf;
+ ASSERT_TRUE(
+ android::base::WriteStringToFile("3000-4000 r-xp 00000 00:00 0 /fake/lib.so\n"
+ "4000-5000 ---p 00000 00:00 0\n"
+ "7000-8000 r-xp 00000 00:00 0 /fake/lib1.so\n"
+ "8000-9000 ---p 00000 00:00 0\n",
+ tf.path));
+
+ maps_.TestSetMapsFile(tf.path);
+ ASSERT_TRUE(maps_.Reparse());
+ ASSERT_EQ(4U, maps_.Total());
+
+ MapInfo* map_info = maps_.Get(2);
+ ASSERT_TRUE(map_info != nullptr);
+ EXPECT_EQ(0x7000U, map_info->start);
+ EXPECT_EQ(0x8000U, map_info->end);
+ EXPECT_EQ(0U, map_info->offset);
+ EXPECT_EQ(PROT_READ | PROT_EXEC, map_info->flags);
+ EXPECT_EQ(maps_.Get(0), map_info->prev_real_map);
+ EXPECT_EQ(maps_.Get(1), map_info->prev_map);
+ EXPECT_EQ("/fake/lib1.so", map_info->name);
+
+ map_info = maps_.Get(3);
+ ASSERT_TRUE(map_info != nullptr);
+ EXPECT_EQ(0x8000U, map_info->start);
+ EXPECT_EQ(0x9000U, map_info->end);
+ EXPECT_EQ(0U, map_info->offset);
+ EXPECT_TRUE(map_info->IsBlank());
+ EXPECT_EQ(maps_.Get(2), map_info->prev_real_map);
+ EXPECT_EQ(maps_.Get(2), map_info->prev_map);
+ EXPECT_TRUE(map_info->name.empty());
+
+ ASSERT_TRUE(
+ android::base::WriteStringToFile("3000-4000 r-xp 00000 00:00 0 /fake/lib.so\n"
+ "4000-5000 ---p 00000 00:00 0\n"
+ "7000-8000 r-xp 00000 00:00 0 /fake/lib1.so\n"
+ "8000-9000 ---p 00000 00:00 0\n"
+ "9000-a000 r-xp 00000 00:00 0 /fake/lib2.so\n"
+ "a000-b000 r-xp 00000 00:00 0 /fake/lib3.so\n",
+ tf.path));
+
+ maps_.TestSetMapsFile(tf.path);
+ ASSERT_TRUE(maps_.Reparse());
+ ASSERT_EQ(6U, maps_.Total());
+
+ map_info = maps_.Get(2);
+ ASSERT_TRUE(map_info != nullptr);
+ EXPECT_EQ(0x7000U, map_info->start);
+ EXPECT_EQ(0x8000U, map_info->end);
+ EXPECT_EQ(0U, map_info->offset);
+ EXPECT_EQ(PROT_READ | PROT_EXEC, map_info->flags);
+ EXPECT_EQ("/fake/lib1.so", map_info->name);
+ EXPECT_EQ(maps_.Get(1), map_info->prev_map);
+ EXPECT_EQ(maps_.Get(0), map_info->prev_real_map);
+
+ map_info = maps_.Get(4);
+ ASSERT_TRUE(map_info != nullptr);
+ EXPECT_EQ(0x9000U, map_info->start);
+ EXPECT_EQ(0xA000U, map_info->end);
+ EXPECT_EQ(0U, map_info->offset);
+ EXPECT_EQ(PROT_READ | PROT_EXEC, map_info->flags);
+ EXPECT_EQ("/fake/lib2.so", map_info->name);
+ EXPECT_EQ(maps_.Get(3), map_info->prev_map);
+ EXPECT_EQ(maps_.Get(2), map_info->prev_real_map);
+
+ map_info = maps_.Get(5);
+ ASSERT_TRUE(map_info != nullptr);
+ EXPECT_EQ(0xA000U, map_info->start);
+ EXPECT_EQ(0xB000U, map_info->end);
+ EXPECT_EQ(0U, map_info->offset);
+ EXPECT_EQ(PROT_READ | PROT_EXEC, map_info->flags);
+ EXPECT_EQ("/fake/lib3.so", map_info->name);
+ EXPECT_EQ(maps_.Get(4), map_info->prev_map);
+ EXPECT_EQ(maps_.Get(4), map_info->prev_real_map);
+}
+
} // namespace unwindstack