diff --git a/Utils.cpp b/Utils.cpp index a66e33c..202b98d 100644 --- a/Utils.cpp +++ b/Utils.cpp @@ -1017,13 +1017,20 @@ status_t MountUserFuse(userid_t user_id, const std::string& absolute_lower_path, std::string pass_through_path( StringPrintf("%s/%s", pre_pass_through_path.c_str(), relative_upper_path.c_str())); - // Create directories. + // Ensure that /mnt/user is 0700. With FUSE, apps don't need access to /mnt/user paths directly. + // Without FUSE however, apps need /mnt/user access so /mnt/user in init.rc is 0755 until here + auto result = PrepareDir("/mnt/user", 0700, AID_ROOT, AID_ROOT); + if (result != android::OK) { + PLOG(ERROR) << "Failed to prepare directory /mnt/user"; + return -1; + } + // Shell is neither AID_ROOT nor AID_EVERYBODY. Since it equally needs 'execute' access to // /mnt/user/0 to 'adb shell ls /sdcard' for instance, we set the uid bit of /mnt/user/0 to // AID_SHELL. This gives shell access along with apps running as group everybody (user 0 apps) // These bits should be consistent with what is set in zygote in // com_android_internal_os_Zygote#MountEmulatedStorage on volume bind mount during app fork - auto result = PrepareDir(pre_fuse_path, 0710, user_id ? AID_ROOT : AID_SHELL, + result = PrepareDir(pre_fuse_path, 0710, user_id ? AID_ROOT : AID_SHELL, multiuser_get_uid(user_id, AID_EVERYBODY)); if (result != android::OK) { PLOG(ERROR) << "Failed to prepare directory " << pre_fuse_path;