Merge "libsnapshot: Ensure we can remove bad snapshots when beginning an update."
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index bd1e284..2c5bf75 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -1619,6 +1619,18 @@
// 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)) {
diff --git a/fs_mgr/libsnapshot/snapshot_test.cpp b/fs_mgr/libsnapshot/snapshot_test.cpp
index 25500b5..6ed0129 100644
--- a/fs_mgr/libsnapshot/snapshot_test.cpp
+++ b/fs_mgr/libsnapshot/snapshot_test.cpp
@@ -2021,6 +2021,34 @@
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: