Now it is possible to enable IME during Secure Desktop using a setting in Preferences or using /enableIME switch.
This helps solve issues with some IME that causes VeraCrypt to freeze when selecting keyfile while VeraCrypt secure desktop is active.
See: https://sourceforge.net/p/veracrypt/discussion/general/thread/1e8b9aeacd
Introduce MapIrpDataBuffer to handle Direct/Buffered/Neither I/O, probing & locking pages and allocating a temp MDL when needed.
Replace blind MmGetSystemAddressForMdlSafe usage. clean up TempUserMdl in OnItemCompleted to avoid crashes when MdlAddress is NULL.
Issue reported at https://sourceforge.net/p/veracrypt/discussion/technical/thread/e43bde8d86/
- Replace dynamic GetProcAddress usage with direct SetThreadGroupAffinity call since we run under Windows 10 minimum
- Compute affinity mask based on actual active processor count
- Fix off-by-one when assigning threads to processor groups (use > instead of >=), preventing premature group advance
- Improves correctness on multi-group (>=64 CPU) systems
Replace timer-based TCSleep (which allocated a KTIMER and waited on it) with an
implementation that calls KeDelayExecutionThread. This removes dynamic allocation
and kernel timer usage to simplify the code and reduce resource overhead.
Adds an IRQL <= APC_LEVEL assertion and documents the requirement.
This is safe because TCSleep is always called from code that runs at PASSIVE_LEVEL
Added InterlockedDecrement in the error path when GetPoolBuffer fails for EncryptedIoRequest to ensure accurate tracking of pending IO requests and prevent potential resource leaks.
Major changes:
- Added pooled + elastic work item model with retry/backoff (MAX_WI_RETRIES). removed semaphore usage.
- Introduced two completion threads to reduce contention and latency under heavy IO.
- Added BytesCompleted (per IRP) and ActualBytes (per fragment) for correct short read/write accounting. total read/write stats now reflect real transferred bytes instead of requested length.
- Moved decryption of read fragments into IO thread. completion threads now only finalize IRPs (reduces race window and simplifies flow).
- Deferred final IRP completion via FinalizeOriginalIrp to avoid inline IoCompleteRequest re-entrancy. added safe OOM inline fallback.
- Implemented work item pool drain & orderly shutdown (ActiveWorkItems + NoActiveWorkItemsEvent) with robust stop protocol.
- Replaced semaphore-based work item acquisition with spin lock + free list + event (WorkItemAvailableEvent). added exponential backoff for transient exhaustion.
- Added elastic (on-demand) work item allocation with pool vs dynamic origin tracking (FromPool).
- Added FreeCompletionWorkItemPool() for symmetric cleanup; ensured all threads are explicitly awakened during stop.
- Added second completion thread replacing single CompletionThread.
- Hardened UpdateBuffer: fixed parameter name typo, added bounds/overflow checks using IntSafe (ULongLongAdd), validated Count, guarded sector end computation.
- Fixed GPT/system region write protection logic to pass correct length instead of end offset.
- Ensured ASSERTs use fragment‑relative bounds (cast + length) and avoided mixed 64/32 comparisons.
- Added MAX_WI_RETRIES constant. added WiRetryCount field in EncryptedIoRequest.
- Ensured RemoveLock is released only after all queue/accounting updates (OnItemCompleted).
- Reset/read-ahead logic preserved. read-ahead trigger now based on actual completion & zero pending fragment count.
- General refactoring, clearer separation of concerns (TryAcquireCompletionWorkItem / FinalizeOriginalIrp / HandleCompleteOriginalIrp).
Safety / correctness improvements:
- Accurate short read handling (STATUS_END_OF_FILE with true byte count).
- Eliminated risk of double free or premature RemoveLock release on completion paths.
- Prevented potential overflow in sector end arithmetic.
- Reduced contention and potential deadlock scenarios present with previous semaphore wait path.
- Document HIGH_LEVEL constraints and rationale for pre-building a nonpaged scratch MDL.
- Allocate contiguous scratch buffer with conservative PFN cap (0x7FFFFFFFFFF) and fall back to unlimited cap if needed.
- Replace ASSERT with TC_BUG_CHECK for validation of write MDL mapping at HIGH_LEVEL.
- Safely copy PFNs from prebuilt MDL into caller MDL: compute dst/src page counts, check capacity, copy exact PFNs and retarget MDL header fields (preserve MdlFlags).
- Make DumpData cleanup defensive in unload path.
- comments improvements for clarity and maintainability.
When multiple VeraCrypt.exe instances were launched simultaneously, race conditions
could occur during the WM_INITDIALOG processing phase, potentially causing application
crashes or hang. This was because the initialization logic handles critical operations
like mounting/unmounting volumes and processing favorite volumes that modify global
system state.
This commit:
- Adds a named local session mutex (MainInitMutex) that serializes the WM_INITDIALOG handler
- Implements proper acquisition and release of the mutex during initialization
- Ensures proper cleanup of mutex resources on application exit
This update introduces a screen protection mechanism that leverages the Windows Display Affinity API to prevent screen capture, screen recording, and inclusion in the Windows 11 Recall feature. By default, all VeraCrypt windows, menus, and tooltips are protected. Users can enable or disable this feature through a new setting available in the application Preferences, as well as in the installer and MSI configurations.
This enhances user privacy by mitigating potential leaks of sensitive interface content.
Note: Due to a regression in Windows 11 affecting layered windows, ComboBox dropdowns cannot currently be protected by this mechanism.
The cascade order has been updated so that SM4 is applied after the other cipher(s) (e.g., Serpent). This change reflects standard cryptanalytic guidance, which shows that the overall strength of a cascade is limited by the first encryption stage. Given that SM4 uses a 128-bit key, its post-quantum brute-force resistance is lower than ciphers with a 256-bit key (such as Serpent). By placing SM4 last, we ensure that any potential weakness in SM4 cannot reduce the security margin provided by the stronger cipher.
Mounir IDRASSI