Snap for 5354487 from 3f6e291c6bcf5084f05db5a7f7532adfa309b940 to qt-release (8cdfc17a) · Commits · e / os / android_system_core

fs_mgr/fs_mgr_remount.cpp

+50 −10

Original line number	Diff line number	Diff line
		@@ -42,13 +42,14 @@ namespace {

		[[noreturn]] void usage(int exit_status) {
		LOG(INFO) << getprogname()
		<< " [-h] [-R] [-T fstab_file]\n"
		<< " [-h] [-R] [-T fstab_file] [partition]...\n"
		"\t-h --help\tthis help\n"
		"\t-R --reboot\tdisable verity & reboot to facilitate remount\n"
		"\t-T --fstab\tcustom fstab file location\n"
		"\tpartition\tspecific partition(s) (empty does all)\n"
		"\n"
		"Remount all partitions read-write.\n"
		"-R notwithstanding, verity must be disabled.";
		"Remount specified partition(s) read-write, by name or mount point.\n"
		"-R notwithstanding, verity must be disabled on partition(s).";

		::exit(exit_status);
		}
		@@ -138,6 +139,8 @@ int main(int argc, char* argv[]) {
		BADARG,
		NOT_ROOT,
		NO_FSTAB,
		UNKNOWN_PARTITION,
		INVALID_PARTITION,
		VERITY_PARTITION,
		BAD_OVERLAY,
		NO_MOUNTS,
		@@ -183,11 +186,6 @@ int main(int argc, char* argv[]) {
		}
		}

		if (argc > optind) {
		LOG(ERROR) << "Bad Argument " << argv[optind];
		usage(BADARG);
		}

		// Make sure we are root.
		if (::getuid() != 0) {
		LOG(ERROR) << "must be run as root";
		@@ -211,16 +209,58 @@ int main(int argc, char* argv[]) {
		auto overlayfs_candidates = fs_mgr_overlayfs_candidate_list(fstab);

		// Generate the all remountable partitions sub-list
		android::fs_mgr::Fstab partitions;
		android::fs_mgr::Fstab all;
		for (auto const& entry : fstab) {
		if (!remountable_partition(entry)) continue;
		if (overlayfs_candidates.empty() \|\|
		GetEntryForMountPoint(&overlayfs_candidates, entry.mount_point) \|\|
		(is_wrapped(overlayfs_candidates, entry) == nullptr)) {
		partitions.emplace_back(entry);
		all.emplace_back(entry);
		}
		}

		// Parse the unique list of valid partition arguments.
		android::fs_mgr::Fstab partitions;
		for (; argc > optind; ++optind) {
		auto partition = std::string(argv[optind]);
		if (partition.empty()) continue;
		if (partition == "/") partition = "/system";
		auto find_part = [&partition](const auto& entry) {
		const auto mount_point = system_mount_point(entry);
		if (partition == mount_point) return true;
		if (partition == android::base::Basename(mount_point)) return true;
		return false;
		};
		// Do we know about the partition?
		auto it = std::find_if(fstab.begin(), fstab.end(), find_part);
		if (it == fstab.end()) {
		LOG(ERROR) << "Unknown partition " << partition << ", skipping";
		retval = UNKNOWN_PARTITION;
		continue;
		}
		// Is that one covered by an existing overlayfs?
		auto wrap = is_wrapped(overlayfs_candidates, *it);
		if (wrap) {
		LOG(INFO) << "partition " << partition << " covered by overlayfs for "
		<< wrap->mount_point << ", switching";
		partition = system_mount_point(*wrap);
		}
		// Is it a remountable partition?
		it = std::find_if(all.begin(), all.end(), find_part);
		if (it == all.end()) {
		LOG(ERROR) << "Invalid partition " << partition << ", skipping";
		retval = INVALID_PARTITION;
		continue;
		}
		if (GetEntryForMountPoint(&partitions, it->mount_point) == nullptr) {
		partitions.emplace_back(*it);
		}
		}

		if (partitions.empty() && !retval) {
		partitions = all;
		}

		// Check verity and optionally setup overlayfs backing.
		auto reboot_later = false;
		for (auto it = partitions.begin(); it != partitions.end();) {

fs_mgr/tests/adb-remount-test.sh

+7 −3

Original line number	Diff line number	Diff line
		@@ -620,7 +620,7 @@ if [ "orange" = "`get_property ro.boot.verifiedbootstate`" -a \

		echo "${GREEN}[ RUN ]${NORMAL} Testing adb shell su root remount -R command" >&2

		adb_su remount -R </dev/null \|\| true
		adb_su remount -R system </dev/null \|\| true
		sleep 2
		adb_wait 2m \|\|
		die "waiting for device after remount -R `usb_status`"
		@@ -1159,10 +1159,12 @@ adb_reboot &&
		die "lost device after reboot to ro state (USB stack broken?)"
		adb_sh grep " /vendor .* rw," /proc/mounts >/dev/null </dev/null &&
		die "/vendor is not read-only"
		adb_su remount </dev/null \|\|
		adb_su remount vendor </dev/null \|\|
		die "remount command"
		adb_sh grep " /vendor .* rw," /proc/mounts >/dev/null </dev/null \|\|
		die "/vendor is not read-write"
		adb_sh grep " /system .* rw," /proc/mounts >/dev/null </dev/null &&
		die "/vendor is not read-only"
		echo "${GREEN}[ OK ]${NORMAL} remount command works from setup" >&2

		# Prerequisite is an overlayfs deconstructed device but with verity disabled.
		@@ -1177,10 +1179,12 @@ adb_reboot &&
		die "lost device after reboot after wipe (USB stack broken?)"
		adb_sh grep " /vendor .* rw," /proc/mounts >/dev/null </dev/null &&
		die "/vendor is not read-only"
		adb_su remount </dev/null \|\|
		adb_su remount vendor </dev/null \|\|
		die "remount command"
		adb_sh grep " /vendor .* rw," /proc/mounts >/dev/null </dev/null \|\|
		die "/vendor is not read-write"
		adb_sh grep " /system .* rw," /proc/mounts >/dev/null </dev/null &&
		die "/system is not read-only"
		echo "${GREEN}[ OK ]${NORMAL} remount command works from scratch" >&2

		restore

init/builtins.cpp

+10 −1

Original line number	Diff line number	Diff line
		@@ -1119,13 +1119,21 @@ static Result<Success> do_parse_apex_configs(const BuiltinArguments& args) {
		}

		static Result<Success> do_setup_runtime_bionic(const BuiltinArguments& args) {
		if (SwitchToDefaultMountNamespace()) {
		if (SetupRuntimeBionic()) {
		return Success();
		} else {
		return Error() << "Failed to setup runtime bionic";
		}
		}

		static Result<Success> do_enter_default_mount_ns(const BuiltinArguments& args) {
		if (SwitchToDefaultMountNamespace()) {
		return Success();
		} else {
		return Error() << "Failed to enter into default mount namespace";
		}
		}

		// Builtin-function-map start
		const BuiltinFunctionMap::Map& BuiltinFunctionMap::map() const {
		constexpr std::size_t kMax = std::numeric_limits<std::size_t>::max();
		@@ -1177,6 +1185,7 @@ const BuiltinFunctionMap::Map& BuiltinFunctionMap::map() const {
		{"start", {1, 1, {false, do_start}}},
		{"stop", {1, 1, {false, do_stop}}},
		{"swapon_all", {1, 1, {false, do_swapon_all}}},
		{"enter_default_mount_ns", {0, 0, {false, do_enter_default_mount_ns}}},
		{"symlink", {2, 2, {true, do_symlink}}},
		{"sysclktz", {1, 1, {false, do_sysclktz}}},
		{"trigger", {1, 1, {false, do_trigger}}},

init/first_stage_init.cpp

+4 −0

Original line number	Diff line number	Diff line
		@@ -155,6 +155,10 @@ int FirstStageMain(int argc, char** argv) {
		// part of the product partition, e.g. because they are mounted read-write.
		CHECKCALL(mkdir("/mnt/product", 0755));

		// /apex is used to mount APEXes
		CHECKCALL(mount("tmpfs", "/apex", "tmpfs", MS_NOEXEC \| MS_NOSUID \| MS_NODEV,
		"mode=0755,uid=0,gid=0"));

		#undef CHECKCALL

		// Now that tmpfs is mounted on /dev and we have /dev/kmsg, we can actually

init/mount_namespace.cpp

+17 −1

Original line number	Diff line number	Diff line
		@@ -172,6 +172,11 @@ bool SetupMountNamespaces() {
		kBionicLibsMountPointDir64))
		return false;

		// /apex is also a private mountpoint to give different sets of APEXes for
		// the bootstrap and default mount namespaces. The processes running with
		// the bootstrap namespace get APEXes from the read-only partition.
		if (!(MakePrivate("/apex"))) return false;

		bootstrap_ns_fd.reset(OpenMountNamespace());
		bootstrap_ns_id = GetMountNamespaceId();

		@@ -227,6 +232,17 @@ bool SwitchToDefaultMountNamespace() {
		}
		}

		LOG(INFO) << "Switched to default mount namespace";
		return true;
		}

		// TODO(jiyong): remove this when /system/lib/libc.so becomes
		// a symlink to /apex/com.android.runtime/lib/bionic/libc.so
		bool SetupRuntimeBionic() {
		if (IsRecoveryMode()) {
		// We don't have multiple namespaces in recovery mode
		return true;
		}
		// Bind-mount bionic from the runtime APEX since it is now available. Note
		// that in case of IsBionicUpdatable() == false, these mounts are over the
		// existing existing bind mounts for the bootstrap bionic, which effectively
		@@ -238,7 +254,7 @@ bool SwitchToDefaultMountNamespace() {
		kBionicLibsMountPointDir64))
		return false;

		LOG(INFO) << "Switched to default mount namespace";
		LOG(INFO) << "Runtime bionic is set up";
		return true;
		}