Command to move private app data between volumes.
New "mvuserdata" command will move all private app data from one
volume UUID to another. It leverages the existing "cp" toybox
command to do the heavy lifting for all known users, preserving
details like timestamps and permissions. It invokes restorecon()
to correctly label the new location when the copy is finished.
Changes installd to no longer drop capabilities, so we run as root
again. This also allows us to exec "cp" with CAP_DAC_OVERRIDE and
CAP_FOWNER still in effect.
Bug: 19993667
Change-Id: I1f407a7c4a1af97ca5afc27b04eb16b4936cbdef
diff --git a/cmds/installd/commands.cpp b/cmds/installd/commands.cpp
index 32a03f4..de6fd96 100644
--- a/cmds/installd/commands.cpp
+++ b/cmds/installd/commands.cpp
@@ -16,15 +16,18 @@
#include "installd.h"
+#include <base/stringprintf.h>
+#include <base/logging.h>
+#include <cutils/sched_policy.h>
+#include <diskusage/dirsize.h>
+#include <logwrap/logwrap.h>
+#include <system/thread_defs.h>
+#include <selinux/android.h>
+
#include <inttypes.h>
#include <sys/capability.h>
#include <sys/file.h>
-#include <cutils/sched_policy.h>
-#include <diskusage/dirsize.h>
-#include <selinux/android.h>
-#include <system/thread_defs.h>
-#include <base/stringprintf.h>
-#include <base/logging.h>
+#include <unistd.h>
using android::base::StringPrintf;
@@ -38,6 +41,8 @@
dir_rec_t android_mnt_expand_dir;
dir_rec_array_t android_system_dirs;
+static const char* kCpPath = "/system/bin/cp";
+
int install(const char *uuid, const char *pkgname, uid_t uid, gid_t gid, const char *seinfo)
{
if ((uid < AID_SYSTEM) || (gid < AID_SYSTEM)) {
@@ -172,6 +177,80 @@
return 0;
}
+int move_user_data(const char *from_uuid, const char *to_uuid,
+ const char *package_name, appid_t appid, const char* seinfo) {
+ std::vector<userid_t> users = get_known_users(from_uuid);
+
+ // Copy package private data for all known users
+ for (auto user : users) {
+ std::string from(create_package_data_path(from_uuid, package_name, user));
+ std::string to(create_package_data_path(to_uuid, package_name, user));
+ std::string to_user(create_data_user_path(to_uuid, user));
+
+ // Data source may not exist for all users; that's okay
+ if (access(from.c_str(), F_OK) != 0) {
+ LOG(INFO) << "Missing source " << from;
+ continue;
+ }
+
+ std::string user_path(create_data_user_path(to_uuid, user));
+ if (fs_prepare_dir(user_path.c_str(), 0771, AID_SYSTEM, AID_SYSTEM) != 0) {
+ LOG(ERROR) << "Failed to prepare user target " << user_path;
+ goto fail;
+ }
+
+ uid_t uid = multiuser_get_uid(user, appid);
+ if (make_user_data(to_uuid, package_name, uid, user, seinfo) != 0) {
+ LOG(ERROR) << "Failed to create package target " << to;
+ goto fail;
+ }
+
+ char *argv[] = {
+ (char*) kCpPath,
+ (char*) "-F", /* delete any existing destination file first (--remove-destination) */
+ (char*) "-p", /* preserve timestamps, ownership, and permissions */
+ (char*) "-R", /* recurse into subdirectories (DEST must be a directory) */
+ (char*) "-P", /* Do not follow symlinks [default] */
+ (char*) "-d", /* don't dereference symlinks */
+ (char*) from.c_str(),
+ (char*) to_user.c_str()
+ };
+
+ LOG(DEBUG) << "Copying " << from << " to " << to;
+ int rc = android_fork_execvp(ARRAY_SIZE(argv), argv, NULL, false, true);
+
+ if (rc != 0) {
+ LOG(ERROR) << "Failed copying " << from << " to " << to
+ << ": status " << rc;
+ goto fail;
+ }
+
+ if (restorecon_data(to_uuid, package_name, seinfo, uid) != 0) {
+ LOG(ERROR) << "Failed to restorecon " << to;
+ goto fail;
+ }
+ }
+
+ // Copy successful, so delete old data
+ for (auto user : users) {
+ std::string from(create_package_data_path(from_uuid, package_name, user));
+ if (delete_dir_contents(from.c_str(), 1, NULL) != 0) {
+ LOG(WARNING) << "Failed to delete " << from;
+ }
+ }
+ return 0;
+
+fail:
+ // Nuke everything we might have already copied
+ for (auto user : users) {
+ std::string to(create_package_data_path(to_uuid, package_name, user));
+ if (delete_dir_contents(to.c_str(), 1, NULL) != 0) {
+ LOG(WARNING) << "Failed to rollback " << to;
+ }
+ }
+ return -1;
+}
+
int make_user_config(userid_t userid)
{
if (ensure_config_user_dirs(userid) == -1) {
@@ -1592,7 +1671,7 @@
continue;
}
- std::string pkgdir(StringPrintf("%s/%s/%s", userdir.c_str(), user, pkgName));
+ std::string pkgdir(StringPrintf("%s%s/%s", userdir.c_str(), user, pkgName));
if (stat(pkgdir.c_str(), &s) < 0) {
continue;
}