Fixes De data is not backed up correctly when user locked (1/n)

https://android.googlesource.com/platform/frameworks/native/+/fda19ecdd6df8f43d3368781a633792723fb9965/cmds/installd/InstalldNativeService.cpp#933

When an APK is stage installed, snapshotAppData(..., FLAG_STORAGE_DE)
is called before user unlocked. The function bails out early at #937
because the folder is still encrypted.

We should move the if block at #958 above so we can back up De data
correctly even when Ce directories not ready.

Note we have to check if the De folder exists before making a copy.

(Cherry-picked from 1d643c77d3fcb7dfe0bf4dabed2964bbfca04c6f)

Bug: 169594054
Test: atest StagedRollbackTest
Merged-In: I2ca810bd9495de3bed58378a41b47863c6e8f8dd
Change-Id: I2ca810bd9495de3bed58378a41b47863c6e8f8dd

1 files changed, 27 insertions, 24 deletions

diff --git a/cmds/installd/InstalldNativeService.cpp b/cmds/installd/InstalldNativeService.cpp
index 34727270e4..856b545c7c 100644
--- a/cmds/installd/InstalldNativeService.cpp
+++ b/cmds/installd/InstalldNativeService.cpp
@@ -876,6 +876,33 @@ binder::Status InstalldNativeService::snapshotAppData(
 
     auto scope_guard = android::base::make_scope_guard(deleter);
 
+    if (storageFlags & FLAG_STORAGE_DE) {
+        auto from = create_data_user_de_package_path(volume_uuid, user, package_name);
+        auto to = create_data_misc_de_rollback_path(volume_uuid, user, snapshotId);
+        auto rollback_package_path = create_data_misc_de_rollback_package_path(volume_uuid, user,
+            snapshotId, package_name);
+
+        int rc = create_dir_if_needed(to.c_str(), kRollbackFolderMode);
+        if (rc != 0) {
+            return error(rc, "Failed to create folder " + to);
+        }
+
+        rc = delete_dir_contents(rollback_package_path, true /* ignore_if_missing */);
+        if (rc != 0) {
+            return error(rc, "Failed clearing existing snapshot " + rollback_package_path);
+        }
+
+        // Check if we have data to copy.
+        if (access(from.c_str(), F_OK) == 0) {
+          rc = copy_directory_recursive(from.c_str(), to.c_str());
+        }
+        if (rc != 0) {
+            res = error(rc, "Failed copying " + from + " to " + to);
+            clear_de_on_exit = true;
+            return res;
+        }
+    }
+
     // The app may not have any data at all, in which case it's OK to skip here.
     auto from_ce = create_data_user_ce_package_path(volume_uuid, user, package_name);
     if (access(from_ce.c_str(), F_OK) != 0) {
@@ -901,30 +928,6 @@ binder::Status InstalldNativeService::snapshotAppData(
         LOG(WARNING) << "Failed to clear code_cache of app " << packageName;
     }
 
-    if (storageFlags & FLAG_STORAGE_DE) {
-        auto from = create_data_user_de_package_path(volume_uuid, user, package_name);
-        auto to = create_data_misc_de_rollback_path(volume_uuid, user, snapshotId);
-        auto rollback_package_path = create_data_misc_de_rollback_package_path(volume_uuid, user,
-            snapshotId, package_name);
-
-        int rc = create_dir_if_needed(to.c_str(), kRollbackFolderMode);
-        if (rc != 0) {
-            return error(rc, "Failed to create folder " + to);
-        }
-
-        rc = delete_dir_contents(rollback_package_path, true /* ignore_if_missing */);
-        if (rc != 0) {
-            return error(rc, "Failed clearing existing snapshot " + rollback_package_path);
-        }
-
-        rc = copy_directory_recursive(from.c_str(), to.c_str());
-        if (rc != 0) {
-            res = error(rc, "Failed copying " + from + " to " + to);
-            clear_de_on_exit = true;
-            return res;
-        }
-    }
-
     if (storageFlags & FLAG_STORAGE_CE) {
         auto from = create_data_user_ce_package_path(volume_uuid, user, package_name);
         auto to = create_data_misc_ce_rollback_path(volume_uuid, user, snapshotId);