Merge "libsnapshot: Ensure we can remove bad snapshots when beginning an update." (7ab8f2ee) · Commits · e / os / android_system_core

fs_mgr/libsnapshot/snapshot.cpp

+12 −0

Original line number	Diff line number	Diff line
		@@ -1619,6 +1619,18 @@ bool SnapshotManager::RemoveAllSnapshots(LockedFile* lock) {
		// as dm-snapshot (for example, after merge completes).
		bool should_unmap = current_slot != Slot::Target;
		bool should_delete = ShouldDeleteSnapshot(flashing_status, current_slot, name);
		if (should_unmap && android::base::EndsWith(name, device_->GetSlotSuffix())) {
		// Something very unexpected has happened - we want to unmap this
		// snapshot, but it's on the wrong slot. We can't unmap an active
		// partition. If this is not really a snapshot, skip the unmap
		// step.
		auto& dm = DeviceMapper::Instance();
		if (dm.GetState(name) == DmDeviceState::INVALID \|\| !IsSnapshotDevice(name)) {
		LOG(ERROR) << "Detected snapshot " << name << " on " << current_slot << " slot"
		<< " for source partition; removing without unmap.";
		should_unmap = false;
		}
		}

		bool partition_ok = true;
		if (should_unmap && !UnmapPartitionWithSnapshot(lock, name)) {

+28 −0

Original line number	Diff line number	Diff line
		@@ -2021,6 +2021,34 @@ TEST_F(SnapshotUpdateTest, MapAllSnapshots) {
		ASSERT_TRUE(IsPartitionUnchanged("sys_b"));
		}

		TEST_F(SnapshotUpdateTest, CancelOnTargetSlot) {
		AddOperationForPartitions();

		// Execute the update from B->A.
		test_device->set_slot_suffix("_b");
		ASSERT_TRUE(sm->BeginUpdate());
		ASSERT_TRUE(sm->CreateUpdateSnapshots(manifest_));

		std::string path;
		ASSERT_TRUE(CreateLogicalPartition(
		CreateLogicalPartitionParams{
		.block_device = fake_super,
		.metadata_slot = 0,
		.partition_name = "sys_a",
		.timeout_ms = 1s,
		.partition_opener = opener_.get(),
		},
		&path));

		// Hold sys_a open so it can't be unmapped.
		unique_fd fd(open(path.c_str(), O_RDONLY));

		// Switch back to "A", make sure we can cancel. Instead of unmapping sys_a
		// we should simply delete the old snapshots.
		test_device->set_slot_suffix("_a");
		ASSERT_TRUE(sm->BeginUpdate());
		}

		class FlashAfterUpdateTest : public SnapshotUpdateTest,
		public WithParamInterface<std::tuple<uint32_t, bool>> {
		public: