diff --git a/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp b/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp
index bd69ac6..e736847 100644
--- a/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp
+++ b/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp
@@ -399,8 +399,14 @@
                       "operation writes.";
         return false;
     }
+
     header_.sequence_data_count = num_ops;
+
+    // Ensure next_data_pos_ is updated as previously initialized + the newly added sequence buffer.
+    CHECK_EQ(next_data_pos_ + header_.sequence_data_count * sizeof(uint32_t),
+             GetDataOffset(header_));
     next_data_pos_ = GetDataOffset(header_);
+
     if (!android::base::WriteFullyAtOffset(fd_, data, sizeof(data[0]) * num_ops,
                                            GetSequenceOffset(header_))) {
         PLOG(ERROR) << "writing sequence buffer failed";