Merge "Switch sdcardfs over to bind mounts."
diff --git a/sdcard/sdcard.cpp b/sdcard/sdcard.cpp
index bc502a0..f2ea3be 100644
--- a/sdcard/sdcard.cpp
+++ b/sdcard/sdcard.cpp
@@ -331,6 +331,27 @@
return true;
}
+static bool sdcardfs_setup_bind_remount(const std::string& source_path, const std::string& dest_path,
+ gid_t gid, mode_t mask) {
+ std::string opts = android::base::StringPrintf("mask=%d,gid=%d", mask, gid);
+
+ if (mount(source_path.c_str(), dest_path.c_str(), nullptr,
+ MS_BIND , nullptr) != 0) {
+ PLOG(ERROR) << "failed to bind mount sdcardfs filesystem";
+ return false;
+ }
+
+ if (mount(source_path.c_str(), dest_path.c_str(), "none",
+ MS_REMOUNT, opts.c_str()) != 0) {
+ PLOG(ERROR) << "failed to mount sdcardfs filesystem";
+ if (umount2(dest_path.c_str(), MNT_DETACH))
+ LOG(WARNING) << "Failed to unmount bind";
+ return false;
+ }
+
+ return true;
+}
+
static void run_sdcardfs(const std::string& source_path, const std::string& label, uid_t uid,
gid_t gid, userid_t userid, bool multi_user, bool full_write) {
std::string dest_path_default = "/mnt/runtime/default/" + label;
@@ -343,9 +364,8 @@
// permissions are completely masked off.
if (!sdcardfs_setup(source_path, dest_path_default, uid, gid, multi_user, userid,
AID_SDCARD_RW, 0006)
- || !sdcardfs_setup(source_path, dest_path_read, uid, gid, multi_user, userid,
- AID_EVERYBODY, 0027)
- || !sdcardfs_setup(source_path, dest_path_write, uid, gid, multi_user, userid,
+ || !sdcardfs_setup_bind_remount(dest_path_default, dest_path_read, AID_EVERYBODY, 0027)
+ || !sdcardfs_setup_bind_remount(dest_path_default, dest_path_write,
AID_EVERYBODY, full_write ? 0007 : 0027)) {
LOG(FATAL) << "failed to sdcardfs_setup";
}
@@ -355,9 +375,9 @@
// deep inside attr_from_stat().
if (!sdcardfs_setup(source_path, dest_path_default, uid, gid, multi_user, userid,
AID_SDCARD_RW, 0006)
- || !sdcardfs_setup(source_path, dest_path_read, uid, gid, multi_user, userid,
+ || !sdcardfs_setup_bind_remount(dest_path_default, dest_path_read,
AID_EVERYBODY, full_write ? 0027 : 0022)
- || !sdcardfs_setup(source_path, dest_path_write, uid, gid, multi_user, userid,
+ || !sdcardfs_setup_bind_remount(dest_path_default, dest_path_write,
AID_EVERYBODY, full_write ? 0007 : 0022)) {
LOG(FATAL) << "failed to sdcardfs_setup";
}