Merge "fs_mgr_overlayfs: Don't preemptively change mount propagation type" into main (37c9fe87) · Commits · e / os / android_system_core

fs_mgr/fs_mgr_overlayfs_mount.cpp

+23 −6

Original line number	Diff line number	Diff line
		@@ -412,6 +412,8 @@ static bool fs_mgr_overlayfs_mount_one(const FstabEntry& fstab_entry) {
		bool retval = true;
		bool move_dir_shared = true;
		bool parent_shared = true;
		bool parent_have_parent = false;
		bool parent_made_private = false;
		bool root_shared = true;
		bool root_made_private = false;

		@@ -443,6 +445,10 @@ static bool fs_mgr_overlayfs_mount_one(const FstabEntry& fstab_entry) {
		if (entry.mount_point == "/") {
		root_shared = entry.shared_flag;
		}
		// Ignore "/" as we don't overlay "/" directly.
		if (entry.mount_point != "/") {
		parent_have_parent \|= android::base::StartsWith(mount_point, entry.mount_point + "/");
		}
		}

		// Precondition is that kMoveMountTempDir is MS_PRIVATE, otherwise don't try to move any
		@@ -453,11 +459,13 @@ static bool fs_mgr_overlayfs_mount_one(const FstabEntry& fstab_entry) {

		// Need to make the original mountpoint MS_PRIVATE, so that the overlayfs can be MS_MOVE.
		// This could happen if its parent mount is remounted later.
		if (!fs_mgr_overlayfs_set_shared_mount(mount_point, false)) {
		if (parent_have_parent) {
		parent_made_private \|= fs_mgr_overlayfs_set_shared_mount(mount_point, false);
		if (!parent_made_private && errno == EINVAL && mount_point == "/system") {
		// If failed to set "/system" mount type, it might be due to "/system" not being a valid
		// mountpoint after switch root. Retry with "/" in this case.
		if (errno == EINVAL && mount_point == "/system") {
		root_made_private = fs_mgr_overlayfs_set_shared_mount("/", false);
		parent_made_private \|= fs_mgr_overlayfs_set_shared_mount("/", false);
		root_made_private \|= parent_made_private;
		}
		}

		@@ -496,6 +504,15 @@ static bool fs_mgr_overlayfs_mount_one(const FstabEntry& fstab_entry) {
		continue;
		}
		}
		if (!parent_made_private) {
		parent_made_private \|= fs_mgr_overlayfs_set_shared_mount(mount_point, false);
		if (!parent_made_private && errno == EINVAL && mount_point == "/system") {
		// If failed to set "/system" mount type, it might be due to "/system" not being a
		// valid mountpoint after switch root. Retry with "/" in this case.
		parent_made_private \|= fs_mgr_overlayfs_set_shared_mount("/", false);
		root_made_private \|= parent_made_private;
		}
		}

		if (new_entry.shared_flag) {
		new_entry.shared_flag = fs_mgr_overlayfs_set_shared_mount(new_entry.mount_point, false);
		@@ -524,7 +541,7 @@ static bool fs_mgr_overlayfs_mount_one(const FstabEntry& fstab_entry) {
		rmdir(entry.dir.c_str());
		}
		// If the original (overridden) mount was MS_SHARED, then set the overlayfs mount to MS_SHARED.
		if (parent_shared) {
		if (parent_shared && parent_made_private) {
		fs_mgr_overlayfs_set_shared_mount(mount_point, true);
		}
		if (root_shared && root_made_private) {