rustdesk 55ae167394 harden the format-data path against late/duplicate responses ...

The format-data rendezvous had the same single-slot race the file-contents
path just fixed: the channel thread rewrote clipboard->hmem with no lock while
explorer-thread consumers read/freed it, nothing serialized concurrent
requests, and no flag told an expected response from a stray one.

- Add format_request_mutex (serializes the whole request/response cycle) and
  hmem_mutex (guards the hmem hand-off and formatDataRespExpected).
- cliprdr_send_data_request now takes ownership of the response buffer under
  hmem_mutex and returns it to the caller, so a later response cannot touch a
  buffer a consumer is using. All three consumers (GetData, WM_RENDERFORMAT,
  DELAYED_RENDERING) and the WM_CLIPBOARDUPDATE cleanup use the returned/taken
  handle instead of the shared slot.
- The response handler drops any response arriving while formatDataRespExpected
  is clear (late/duplicate/unsolicited), consumes the flag on the first
  response, and no longer dereferences a NULL clipboard in the SetEvent path.

Pre-existing issue, not introduced by this branch; generalizes the
file-contents hardening to the format-data path.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

2026-07-04 18:23:58 +08:00

..

test_invariant_wf_cliprdr.c

harden the format-data path against late/duplicate responses

2026-07-04 18:23:58 +08:00