Try 3:
  - Avoid allocating memory. (Based on Alexandre's comment, thanks.)
  - Use k != root_key instead of k->namelen != 0.
  - Add insufficient buffer test.

---
 dlls/ntdll/tests/reg.c | 19 ++++++++++++++-----
 server/registry.c      | 25 ++++++++++++++++++++++++-
 2 files changed, 38 insertions(+), 6 deletions(-)