Check /mnt/expand paths as if /data.

The layout of adopted storage devices is identical to the internal
userdata partition, so we should re-use the same logic to determine
if a given path is legitimate.

Bug: 77654971
Test: adb shell /data/nativetest64/installd_utils_test/installd_utils_test
Change-Id: I856788a8e9910f618a4f259a20a264e14b46e079

2 files changed, 50 insertions, 11 deletions

diff --git a/cmds/installd/tests/installd_utils_test.cpp b/cmds/installd/tests/installd_utils_test.cpp
index bbff6fb0d7..bcdd03efad 100644
--- a/cmds/installd/tests/installd_utils_test.cpp
+++ b/cmds/installd/tests/installd_utils_test.cpp
@@ -33,7 +33,7 @@
 #define TEST_APP_PRIVATE_DIR "/data/app-private/"
 #define TEST_APP_EPHEMERAL_DIR "/data/app-ephemeral/"
 #define TEST_ASEC_DIR "/mnt/asec/"
-#define TEST_EXPAND_DIR "/mnt/expand/"
+#define TEST_EXPAND_DIR "/mnt/expand/00000000-0000-0000-0000-000000000000/"
 
 #define TEST_SYSTEM_DIR1 "/system/app/"
 #define TEST_SYSTEM_DIR2 "/vendor/app/"
@@ -116,6 +116,41 @@ TEST_F(UtilsTest, IsValidApkPath_Internal) {
             << bad_path5 << " should be rejected as a invalid path";
 }
 
+TEST_F(UtilsTest, IsValidApkPath_TopDir) {
+    EXPECT_EQ(0, validate_apk_path(TEST_DATA_DIR "app/com.example"));
+    EXPECT_EQ(0, validate_apk_path(TEST_EXPAND_DIR "app/com.example"));
+    EXPECT_EQ(-1, validate_apk_path(TEST_DATA_DIR "data/com.example"));
+    EXPECT_EQ(-1, validate_apk_path(TEST_EXPAND_DIR "data/com.example"));
+}
+
+TEST_F(UtilsTest, IsValidApkPath_TopFile) {
+    EXPECT_EQ(0, validate_apk_path(TEST_DATA_DIR "app/com.example/base.apk"));
+    EXPECT_EQ(0, validate_apk_path(TEST_EXPAND_DIR "app/com.example/base.apk"));
+    EXPECT_EQ(-1, validate_apk_path(TEST_DATA_DIR "data/com.example/base.apk"));
+    EXPECT_EQ(-1, validate_apk_path(TEST_EXPAND_DIR "data/com.example/base.apk"));
+}
+
+TEST_F(UtilsTest, IsValidApkPath_OatDir) {
+    EXPECT_EQ(0, validate_apk_path_subdirs(TEST_DATA_DIR "app/com.example/oat"));
+    EXPECT_EQ(0, validate_apk_path_subdirs(TEST_EXPAND_DIR "app/com.example/oat"));
+    EXPECT_EQ(-1, validate_apk_path_subdirs(TEST_DATA_DIR "data/com.example/oat"));
+    EXPECT_EQ(-1, validate_apk_path_subdirs(TEST_EXPAND_DIR "data/com.example/oat"));
+}
+
+TEST_F(UtilsTest, IsValidApkPath_OatDirDir) {
+    EXPECT_EQ(0, validate_apk_path_subdirs(TEST_DATA_DIR "app/com.example/oat/arm64"));
+    EXPECT_EQ(0, validate_apk_path_subdirs(TEST_EXPAND_DIR "app/com.example/oat/arm64"));
+    EXPECT_EQ(-1, validate_apk_path_subdirs(TEST_DATA_DIR "data/com.example/oat/arm64"));
+    EXPECT_EQ(-1, validate_apk_path_subdirs(TEST_EXPAND_DIR "data/com.example/oat/arm64"));
+}
+
+TEST_F(UtilsTest, IsValidApkPath_OatDirDirFile) {
+    EXPECT_EQ(0, validate_apk_path_subdirs(TEST_DATA_DIR "app/com.example/oat/arm64/base.odex"));
+    EXPECT_EQ(0, validate_apk_path_subdirs(TEST_EXPAND_DIR "app/com.example/oat/arm64/base.odex"));
+    EXPECT_EQ(-1, validate_apk_path_subdirs(TEST_DATA_DIR "data/com.example/oat/arm64/base.odex"));
+    EXPECT_EQ(-1, validate_apk_path_subdirs(TEST_EXPAND_DIR "data/com.example/oat/arm64/base.odex"));
+}
+
 TEST_F(UtilsTest, IsValidApkPath_Private) {
     // Internal directories
     const char *private1 = TEST_APP_PRIVATE_DIR "example.apk";
diff --git a/cmds/installd/utils.cpp b/cmds/installd/utils.cpp
index a8c32ed2a5..1ff45e4845 100644
--- a/cmds/installd/utils.cpp
+++ b/cmds/installd/utils.cpp
@@ -855,21 +855,25 @@ bool validate_secondary_dex_path(const std::string& pkgname, const std::string&
  * that path. Returns -1 when an invalid path is encountered and 0 when a valid path
  * is encountered.
  */
-static int validate_apk_path_internal(const char *path, int maxSubdirs) {
-    std::string path_ = path;
-    if (validate_path(android_app_dir, path_, maxSubdirs) == 0) {
-        return 0;
-    } else if (validate_path(android_app_private_dir, path_, maxSubdirs) == 0) {
+static int validate_apk_path_internal(const std::string& path, int maxSubdirs) {
+    if (validate_path(android_app_dir, path, maxSubdirs) == 0) {
         return 0;
-    } else if (validate_path(android_app_ephemeral_dir, path_, maxSubdirs) == 0) {
+    } else if (validate_path(android_app_private_dir, path, maxSubdirs) == 0) {
         return 0;
-    } else if (validate_path(android_asec_dir, path_, maxSubdirs) == 0) {
+    } else if (validate_path(android_app_ephemeral_dir, path, maxSubdirs) == 0) {
         return 0;
-    } else if (validate_path(android_mnt_expand_dir, path_, std::max(maxSubdirs, 2)) == 0) {
+    } else if (validate_path(android_asec_dir, path, maxSubdirs) == 0) {
         return 0;
-    } else {
-        return -1;
+    } else if (android::base::StartsWith(path, android_mnt_expand_dir)) {
+        // Rewrite the path as if it were on internal storage, and test that
+        size_t end = path.find('/', android_mnt_expand_dir.size() + 1);
+        if (end != std::string::npos) {
+            auto modified = path;
+            modified.replace(0, end + 1, android_data_dir);
+            return validate_apk_path_internal(modified, maxSubdirs);
+        }
     }
+    return -1;
 }
 
 int validate_apk_path(const char* path) {