Merge "libsnapshot: Verify the ordering of COW operations." into main
diff --git a/fs_mgr/libsnapshot/libsnapshot_cow/cow_reader.cpp b/fs_mgr/libsnapshot/libsnapshot_cow/cow_reader.cpp
index 489669a..f37aed1 100644
--- a/fs_mgr/libsnapshot/libsnapshot_cow/cow_reader.cpp
+++ b/fs_mgr/libsnapshot/libsnapshot_cow/cow_reader.cpp
@@ -310,9 +310,34 @@
bool CowReader::VerifyMergeOps() {
auto itr = GetMergeOpIter(true);
std::unordered_map<uint64_t, const CowOperation*> overwritten_blocks;
+ bool non_ordered_op_found = false;
+
while (!itr->AtEnd()) {
const auto& op = itr->Get();
uint64_t offset;
+
+ // Op should not be a metadata
+ if (IsMetadataOp(*op)) {
+ LOG(ERROR) << "Metadata op: " << op << " found during merge sequence";
+ return false;
+ }
+
+ // Sequence ops should contain all the ordered ops followed
+ // by Replace and Zero ops. If we find the first op which
+ // is not ordered, that means all ordered ops processing
+ // has been completed.
+ if (!IsOrderedOp(*op)) {
+ non_ordered_op_found = true;
+ }
+
+ // Since, all ordered ops processing has been completed,
+ // check that the subsequent ops are not ordered.
+ if (non_ordered_op_found && IsOrderedOp(*op)) {
+ LOG(ERROR) << "Invalid sequence - non-ordered and ordered ops"
+ << " cannot be mixed during sequence generation";
+ return false;
+ }
+
if (!GetSourceOffset(op, &offset)) {
itr->Next();
continue;