diff --git a/cmds/installd/dexopt.cpp b/cmds/installd/dexopt.cpp
index d534830..2b2725f 100644
--- a/cmds/installd/dexopt.cpp
+++ b/cmds/installd/dexopt.cpp
@@ -1829,6 +1829,11 @@
         result = unlink_if_exists(current_profile) && result;
         result = unlink_if_exists(reference_profile) && result;
 
+        // We upgraded once the location of current profile for secondary dex files.
+        // Check for any previous left-overs and remove them as well.
+        std::string old_current_profile = dex_path + ".prof";
+        result = unlink_if_exists(old_current_profile);
+
         // Try removing the directories as well, they might be empty.
         result = rmdir_if_empty(oat_isa_dir) && result;
         result = rmdir_if_empty(oat_dir) && result;
diff --git a/cmds/installd/tests/installd_utils_test.cpp b/cmds/installd/tests/installd_utils_test.cpp
index dab3236..46ed85f 100644
--- a/cmds/installd/tests/installd_utils_test.cpp
+++ b/cmds/installd/tests/installd_utils_test.cpp
@@ -38,16 +38,6 @@
 
 #define TEST_PROFILE_DIR "/data/misc/profiles"
 
-#define REALLY_LONG_APP_NAME "com.example." \
-        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa." \
-        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa." \
-        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
-
-#define REALLY_LONG_LEAF_NAME "shared_prefs_shared_prefs_shared_prefs_shared_prefs_shared_prefs_" \
-        "shared_prefs_shared_prefs_shared_prefs_shared_prefs_shared_prefs_shared_prefs_" \
-        "shared_prefs_shared_prefs_shared_prefs_shared_prefs_shared_prefs_shared_prefs_" \
-        "shared_prefs_shared_prefs_shared_prefs_shared_prefs_shared_prefs_shared_prefs_"
-
 namespace android {
 namespace installd {
 
@@ -88,6 +78,14 @@
     virtual void TearDown() {
         free(android_system_dirs.dirs);
     }
+
+    std::string create_too_long_path(const std::string& seed) {
+        std::string result = seed;
+        for (size_t i = seed.size(); i < PKG_PATH_MAX; i++) {
+            result += "a";
+        }
+        return result;
+    }
 };
 
 TEST_F(UtilsTest, IsValidApkPath_BadPrefix) {
@@ -388,17 +386,18 @@
             << "Primary user package directory should be created correctly";
 }
 
+
 TEST_F(UtilsTest, CreateMovePath_Fail_AppTooLong) {
     char path[PKG_PATH_MAX];
-
-    EXPECT_EQ(-1, create_move_path(path, REALLY_LONG_APP_NAME, "shared_prefs", 0))
+    std::string really_long_app_name = create_too_long_path("com.example");
+    EXPECT_EQ(-1, create_move_path(path, really_long_app_name.c_str(), "shared_prefs", 0))
             << "Should fail to create move path for primary user";
 }
 
 TEST_F(UtilsTest, CreateMovePath_Fail_LeafTooLong) {
     char path[PKG_PATH_MAX];
-
-    EXPECT_EQ(-1, create_move_path(path, "com.android.test", REALLY_LONG_LEAF_NAME, 0))
+    std::string really_long_leaf_name = create_too_long_path("leaf_");
+    EXPECT_EQ(-1, create_move_path(path, "com.android.test", really_long_leaf_name.c_str(), 0))
             << "Should fail to create move path for primary user";
 }
 
@@ -560,7 +559,7 @@
 }
 
 TEST_F(UtilsTest, CreateSecondaryCurrentProfile) {
-    EXPECT_EQ("/data/user/0/com.example/secondary.dex.prof",
+    EXPECT_EQ("/data/user/0/com.example/oat/secondary.dex.cur.prof",
             create_current_profile_path(/*user*/0,
                     "/data/user/0/com.example/secondary.dex", /*is_secondary*/true));
 }
@@ -571,5 +570,88 @@
                     "/data/user/0/com.example/secondary.dex", /*is_secondary*/true));
 }
 
+static void pass_secondary_dex_validation(const std::string& package_name,
+        const std::string& dex_path, int uid, int storage_flag) {
+    EXPECT_TRUE(validate_secondary_dex_path(package_name, dex_path, /*volume_uuid*/ nullptr, uid,
+            storage_flag))
+            << dex_path << " should be allowed as a valid secondary dex path";
+}
+
+static void fail_secondary_dex_validation(const std::string& package_name,
+        const std::string& dex_path, int uid, int storage_flag) {
+    EXPECT_FALSE(validate_secondary_dex_path(package_name, dex_path, /*volume_uuid*/ nullptr, uid,
+            storage_flag))
+            << dex_path << " should not be allowed as a valid secondary dex path";
+}
+
+TEST_F(UtilsTest, ValidateSecondaryDexFilesPath) {
+    std::string package_name = "com.test.app";
+    std::string app_dir_ce_user_0 = "/data/data/" + package_name;
+    std::string app_dir_ce_user_10 = "/data/user/10/" + package_name;
+
+    std::string app_dir_de_user_0 = "/data/user_de/0/" + package_name;
+    std::string app_dir_de_user_10 = "/data/user_de/10/" + package_name;
+
+    EXPECT_EQ(app_dir_ce_user_0,
+            create_data_user_ce_package_path(nullptr, 0, package_name.c_str()));
+    EXPECT_EQ(app_dir_ce_user_10,
+            create_data_user_ce_package_path(nullptr, 10, package_name.c_str()));
+
+    EXPECT_EQ(app_dir_de_user_0,
+            create_data_user_de_package_path(nullptr, 0, package_name.c_str()));
+    EXPECT_EQ(app_dir_de_user_10,
+            create_data_user_de_package_path(nullptr, 10, package_name.c_str()));
+
+    uid_t app_uid_for_user_0 = multiuser_get_uid(/*user_id*/0, /*app_id*/ 1234);
+    uid_t app_uid_for_user_10 = multiuser_get_uid(/*user_id*/10, /*app_id*/ 1234);
+
+    // Standard path for user 0 on CE storage.
+    pass_secondary_dex_validation(
+        package_name, app_dir_ce_user_0 + "/ce0.dex", app_uid_for_user_0, FLAG_STORAGE_CE);
+    // Standard path for user 10 on CE storage.
+    pass_secondary_dex_validation(
+        package_name, app_dir_ce_user_10 + "/ce10.dex", app_uid_for_user_10, FLAG_STORAGE_CE);
+
+    // Standard path for user 0 on DE storage.
+    pass_secondary_dex_validation(
+        package_name, app_dir_de_user_0 + "/de0.dex", app_uid_for_user_0, FLAG_STORAGE_DE);
+    // Standard path for user 10 on DE storage.
+    pass_secondary_dex_validation(
+        package_name, app_dir_de_user_10 + "/de0.dex", app_uid_for_user_10, FLAG_STORAGE_DE);
+
+    // Dex path for user 0 accessed from user 10.
+    fail_secondary_dex_validation(
+        package_name, app_dir_ce_user_0 + "/path0_from10.dex",
+        app_uid_for_user_10, FLAG_STORAGE_CE);
+
+    // Dex path for CE storage accessed with DE.
+    fail_secondary_dex_validation(
+        package_name, app_dir_ce_user_0 + "/ce_from_de.dex", app_uid_for_user_0, FLAG_STORAGE_DE);
+
+    // Dex path for DE storage accessed with CE.
+    fail_secondary_dex_validation(
+        package_name, app_dir_de_user_0 + "/de_from_ce.dex", app_uid_for_user_0, FLAG_STORAGE_CE);
+
+    // Location which does not start with '/'.
+    fail_secondary_dex_validation(
+        package_name, "without_slash.dex", app_uid_for_user_10, FLAG_STORAGE_DE);
+
+    // The dex file is not in the specified package directory.
+    fail_secondary_dex_validation(
+        "another.package", app_dir_ce_user_0 + "/for_another_package.dex",
+        app_uid_for_user_0, FLAG_STORAGE_DE);
+
+    // The dex path contains indirect directories.
+    fail_secondary_dex_validation(
+        package_name, app_dir_ce_user_0 + "/1/../foo.dex", app_uid_for_user_0, FLAG_STORAGE_CE);
+    fail_secondary_dex_validation(
+        package_name, app_dir_ce_user_0 + "/1/./foo.dex", app_uid_for_user_0, FLAG_STORAGE_CE);
+
+    // Super long path.
+    std::string too_long = create_too_long_path("too_long_");
+    fail_secondary_dex_validation(
+        package_name, app_dir_ce_user_10 + "/" + too_long, app_uid_for_user_10, FLAG_STORAGE_CE);
+}
+
 }  // namespace installd
 }  // namespace android
diff --git a/cmds/installd/utils.cpp b/cmds/installd/utils.cpp
index 7c05417..0faddf0 100644
--- a/cmds/installd/utils.cpp
+++ b/cmds/installd/utils.cpp
@@ -238,13 +238,38 @@
 
 // Keep profile paths in sync with ActivityThread and LoadedApk.
 const std::string PROFILE_EXT = ".prof";
+const std::string CURRENT_PROFILE_EXT = ".cur";
 const std::string PRIMARY_PROFILE_NAME = "primary" + PROFILE_EXT;
 
+// Gets the parent directory and the file name for the given secondary dex path.
+// Returns true on success, false on failure (if the dex_path does not have the expected
+// structure).
+static bool get_secondary_dex_location(const std::string& dex_path,
+        std::string* out_dir_name, std::string* out_file_name) {
+   size_t dirIndex = dex_path.rfind('/');
+   if (dirIndex == std::string::npos) {
+        return false;
+   }
+   if (dirIndex == dex_path.size() - 1) {
+        return false;
+   }
+   *out_dir_name = dex_path.substr(0, dirIndex);
+   *out_file_name = dex_path.substr(dirIndex + 1);
+
+   return true;
+}
+
 std::string create_current_profile_path(userid_t user, const std::string& location,
         bool is_secondary_dex) {
     if (is_secondary_dex) {
-        // Secondary dex profiles are stored next to the dex files using .prof extension.
-        return StringPrintf("%s%s", location.c_str(), PROFILE_EXT.c_str());
+        // Secondary dex current profiles are stored next to the dex files under the oat folder.
+        std::string dex_dir;
+        std::string dex_name;
+        CHECK(get_secondary_dex_location(location, &dex_dir, &dex_name))
+                << "Unexpected dir structure for secondary dex " << location;
+        return StringPrintf("%s/oat/%s%s%s",
+                dex_dir.c_str(), dex_name.c_str(), CURRENT_PROFILE_EXT.c_str(),
+                PROFILE_EXT.c_str());
     } else {
         // Profiles for primary apks are under /data/misc/profiles/cur.
         std::string profile_dir = create_primary_current_profile_package_dir_path(user, location);
@@ -255,12 +280,10 @@
 std::string create_reference_profile_path(const std::string& location, bool is_secondary_dex) {
     if (is_secondary_dex) {
         // Secondary dex reference profiles are stored next to the dex files under the oat folder.
-        size_t dirIndex = location.rfind('/');
-        CHECK(dirIndex != std::string::npos)
+        std::string dex_dir;
+        std::string dex_name;
+        CHECK(get_secondary_dex_location(location, &dex_dir, &dex_name))
                 << "Unexpected dir structure for secondary dex " << location;
-
-        std::string dex_dir = location.substr(0, dirIndex);
-        std::string dex_name = location.substr(dirIndex +1);
         return StringPrintf("%s/oat/%s%s",
                 dex_dir.c_str(), dex_name.c_str(), PROFILE_EXT.c_str());
     } else {
@@ -781,21 +804,30 @@
         const char* volume_uuid, int uid, int storage_flag) {
     CHECK(storage_flag == FLAG_STORAGE_CE || storage_flag == FLAG_STORAGE_DE);
 
+    // Empty paths are not allowed.
+    if (dex_path.empty()) { return false; }
+    // First character should always be '/'. No relative paths.
+    if (dex_path[0] != '/') { return false; }
+    // The last character should not be '/'.
+    if (dex_path[dex_path.size() - 1] == '/') { return false; }
+    // There should be no '.' after the directory marker.
+    if (dex_path.find("/.") != std::string::npos) { return false; }
+    // The path should be at most PKG_PATH_MAX long.
+    if (dex_path.size() > PKG_PATH_MAX) { return false; }
+
+    // The dex_path should be under the app data directory.
     std::string app_private_dir = storage_flag == FLAG_STORAGE_CE
         ? create_data_user_ce_package_path(
                 volume_uuid, multiuser_get_user_id(uid), pkgname.c_str())
         : create_data_user_de_package_path(
                 volume_uuid, multiuser_get_user_id(uid), pkgname.c_str());
-    dir_rec_t dir;
-    if (get_path_from_string(&dir, app_private_dir.c_str()) != 0) {
-        LOG(WARNING) << "Could not get dir rec for " << app_private_dir;
+
+    if (strncmp(dex_path.c_str(), app_private_dir.c_str(), app_private_dir.size()) != 0) {
         return false;
     }
-    // Usually secondary dex files have a nested directory structure.
-    // Pick at most 10 subdirectories when validating (arbitrary value).
-    // If the secondary dex file is >10 directory nested then validation will
-    // fail and the file will not be compiled.
-    return validate_path(&dir, dex_path.c_str(), /*max_subdirs*/ 10) == 0;
+
+    // If we got here we have a valid path.
+    return true;
 }
 
 /**