aboutsummaryrefslogtreecommitdiffstats
Commit message (Collapse)AuthorAgeFilesLines
* driver: fix missed-wakeup race in ring buffer Alertable signalingHEADmasterSimon Rozman2026-03-182-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add MemoryBarrier() between store-load pairs in the Dekker-style synchronization used by the Receive ring's Alertable/Tail protocol. On x86-64, WriteRelease/ReadAcquire only prevent compiler reordering and provide acquire/release semantics, but do not emit MFENCE — the only instruction that prevents store-load reordering across cores. Without a full barrier, both the userspace producer and the kernel consumer can simultaneously read stale values: Userspace: STORE(Tail) ... LOAD(Alertable) -> sees FALSE (stale) Driver: STORE(Alertable=TRUE) ... LOAD(Tail) -> sees old tail The driver then enters KeWaitForMultipleObjects with no pending SetEvent, sleeping until a TCP retransmission (typically 4-5s later) re-triggers the send path and wins the race. The fix adds MemoryBarrier() (MFENCE on x86) on both sides: - api/session.c WintunSendPacket: between WriteULongRelease(Tail) and ReadAcquire(Alertable) - driver/twintun.c TunProcessReceiveData: between WriteRelease(Alertable, TRUE) and ReadULongAcquire(Tail) This guarantees that at least one side always observes the other's store, preventing the missed wakeup while preserving the Alertable optimization that avoids unnecessary SetEvent syscalls. Reported-by: Alexey Lapuka <alexey@twingate.com> Reference: https://lists.zx2c4.com/pipermail/wireguard/2026-February/009523.html Signed-off-by: Simon Rozman <simon.rozman@amebis.si>
* driver: fix race condition at Ring->HeadSimon Rozman2026-02-201-6/+5
| | | | | | | | | | | | | | | | | | | | | | | | This PR fixes a critical race condition in the Wintun driver that causes ring buffer overruns when multiple UDP senders operate in parallel. The issue occurred because multiple threads could read the same Ring->Head value without synchronization, leading to concurrent modifications that corrupted the ring buffer and resulted in ERROR_INVALID_DATA errors. In order to prevent buffer overrun (which was observed while sending multiple high throughput UDP streams from different threads) I move the driver spinlock to protect Ring buffer Head. I observed that the Ring->Head was taken and manipulated later on with just a `ReadULongAcquire` which isn't OK when 2 are trying to manipulate it later on based on the same received value. A fix was provided in 4fc590853b8281552631b79dacda484a5782f3bf, but it didn't solve the issue. Reported-by: odedkatz <katz.oded@gmail.com> Reference: https://lists.zx2c4.com/pipermail/wireguard/2026-February/009489.html Reference: https://lists.zx2c4.com/pipermail/wireguard/2026-February/009510.html Signed-off-by: Simon Rozman <simon.rozman@amebis.si>
* driver: explicitly terminate NBLSimon Rozman2026-02-201-3/+4
| | | | | | | | | | | The ActiveNbls list uses MINIPORT_RESERVED[1] as the next pointer, but never NULL-terminates the tail entry. It was never observed the allocated NBL would contain a non-zero MiniportReserved array, but this being unspecified in the official documentation, let's stay out of "unspecified" area. Reference: https://learn.microsoft.com/en-us/windows-hardware/drivers/ddi/nbl/ns-nbl-net_buffer_list Signed-off-by: Simon Rozman <simon.rozman@amebis.si>
* driver: introduce NET_BUFFER_LIST_OFFSET helperSimon Rozman2026-02-091-4/+6
| | | | | | | | | Since NET_BUFFER_LIST_MINIPORT_RESERVED[1] is assigned our next NBL pointer and we have a macro for it (NET_BUFFER_LIST_NEXT_NBL_EX), let's have a macro for NET_BUFFER_LIST_MINIPORT_RESERVED[0], we assigned NBL offset and flags to, too. Signed-off-by: Simon Rozman <simon.rozman@amebis.si>
* doc: fix WintunReceivePacket nameSimon Rozman2026-02-092-4/+4
| | | | | | There is no `WintunReceivePackets`. Just `WintunReceivePacket`. Signed-off-by: Simon Rozman <simon.rozman@amebis.si>
* api: ignore instance not found when removing instanceSimon Rozman2025-05-211-0/+2
| | | | | | | | | Should SetupAPI report ERROR_PATH_NOT_FOUND on attempt to remove the adapter instance, the adapter is already gone and we already have what we wanted. Reference: https://lists.zx2c4.com/pipermail/wireguard/2025-February/008762.html Signed-off-by: Simon Rozman <simon@rozman.si>
* driver: fix spelling mistakes in commentsJason A. Donenfeld2022-05-231-2/+2
| | | | | Suggested-by: Dimitri Papadopoulos <dimitri.papadopoulos@cea.fr> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* README: mention Windows 11Simon Rozman2022-04-221-1/+1
| | | | | Reported-by: Dimitri Papadopoulos Orfanos <dimitri.papadopoulos@cea.fr> Signed-off-by: Simon Rozman <simon@rozman.si>
* api: header: silence MSVC warnings for MSVC onlySimon Rozman2021-12-031-3/+7
| | | | | | | MinGW ignores unknown `#pragma warning` lines, but displays a warning nevertheless. Signed-off-by: Simon Rozman <simon@rozman.si>
* proj: stop building for arm32Simon Rozman2021-10-251-3/+2
| | | | | | | | | | | | | This does not remove 32-bit ARM compilation support out of the project yet. Shipping of 32-bit ARM drivers became a real challenge: - Microsoft changed policy to prohibit EV-signed drivers - Attestation signing is not supported for this platform - Setting up Windows 8 ARM HCK to get WHQL certification requires a lot of effort if doable in 2021 at all. Signed-off-by: Simon Rozman <simon@rozman.si>
* driver: address Code Analysis warningSimon Rozman2021-10-171-0/+1
| | | | | | | In this case, we're referencing objects by handle for closing user space handles. Should be UserMode, not Irp->RequestorMode as C28126 suggests. Signed-off-by: Simon Rozman <simon@rozman.si>
* driver: allow ring registration from kernelSimon Rozman2021-10-171-4/+4
| | | | Signed-off-by: Simon Rozman <simon@rozman.si>
* driver: address Code Analysis warningsSimon Rozman2021-10-171-1/+2
| | | | Signed-off-by: Simon Rozman <simon@rozman.si>
* version: bump0.14.1Jason A. Donenfeld2021-10-171-1/+1
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* api: main: avoid excessive function castJason A. Donenfeld2021-10-151-4/+3
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* example: remove overly specific castsJason A. Donenfeld2021-10-151-10/+5
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* api: header: fix typoJason A. Donenfeld2021-10-141-1/+1
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* api: use proper instance id boundsJason A. Donenfeld2021-10-145-9/+9
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* api: adapter: handle cases explicitly in dev query callbackJason A. Donenfeld2021-10-141-5/+10
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* downlevelshim: remove in preparation for full WHQLJason A. Donenfeld2021-10-137-159/+4
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* README: correct solution nameJason A. Donenfeld2021-10-121-1/+1
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* version: bump0.14Jason A. Donenfeld2021-10-121-1/+1
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* driver: automatically close long-lived handleJason A. Donenfeld2021-10-124-132/+77
| | | | | | | | | | | | | There's only one handle that's likely to be open in a long lived way: the tun registration handle. So we can force that closed automatically when the device is about to close, if it's been improperly left open. Other handles will indeed hold up closing, but if those exist, they're a sign of a larger bug elsewhere that should be addressed. On the other hand, tun registration handles might legitimately be open during driver upgrades. This also saves us the trouble of dereferencing a freed FileObject as in the general case. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* api: rewrite based on SwDeviceJason A. Donenfeld2021-10-1230-2658/+2376
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* proj: remove SDV and DVL supportSimon Rozman2021-10-111-22/+1
| | | | Signed-off-by: Simon Rozman <simon@rozman.si>
* api: adapter: cleanup wintrust shim if install failsJason A. Donenfeld2021-09-281-6/+6
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* driver: inf: remove LoadOrderGroupJason A. Donenfeld2021-09-241-1/+0
| | | | | | It's useless for PnP drivers. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* driver: allow userspace to write garbageJason A. Donenfeld2021-09-161-2/+3
| | | | | | | | Not discouraging userspace from skipping checking IP packets seems like a bad thing, but they skip it anyway, so at least avoid the DoS due to API misuse. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* driver: Replace depreciated ExAllocatePoolWithTagSimon Rozman2021-09-131-1/+1
| | | | | | | | CodeQL with Windows-Driver-Developer-Supplemental-Tools suggests the ExAllocatePoolWithTag() should no longer be used. The Static Tools Logo Test in HLK spots this in the DVL log and fails. Signed-off-by: Simon Rozman <simon@rozman.si>
* example: disable dad for faster startupJason A. Donenfeld2021-09-091-0/+1
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* props: inverse SDVHacks logicSimon Rozman2021-08-251-2/+2
| | | | | | | SDV is allergic to code analysis. So, when we're doing SDV (SDVHacks is "true"), we need to turn the code analysis off. Signed-off-by: Simon Rozman <simon@rozman.si>
* .gitignore: ignore CodeQL outputSimon Rozman2021-08-251-0/+4
| | | | Signed-off-by: Simon Rozman <simon@rozman.si>
* props: unify import .lib of DLLsSimon Rozman2021-08-102-1/+1
| | | | | | | This moves downlevelshim.lib and those .lib from any future DLLs in this repo to the matching IntDir. Signed-off-by: Simon Rozman <simon@rozman.si>
* api: rundll32: make empty string if no instance idJason A. Donenfeld2021-08-081-1/+1
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* driver: mark as network driver rather than system driverJason A. Donenfeld2021-08-071-1/+1
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* props: tie code analysis to sdv hacks rather than debug buildsJason A. Donenfeld2021-08-042-3/+3
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* version: bump0.13Jason A. Donenfeld2021-08-021-1/+1
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* proj: fix header linesJason A. Donenfeld2021-08-022-2/+2
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* api: incorporate new win7 code signing techniqueJason A. Donenfeld2021-08-027-4/+160
| | | | | | https://git.zx2c4.com/downlevel-driver-enabler/about/ Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* proj: clean up loose endsJason A. Donenfeld2021-08-022-3/+3
| | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* api: remove authenticode supportJason A. Donenfeld2021-08-023-103/+5
| | | | | | Certificates are no longer valid. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* props: use ForcedTargetVersion for overrideJason A. Donenfeld2021-07-302-5/+8
| | | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Simon Rozman <simon@rozman.si>
* editorconfig: farewell wixJason A. Donenfeld2021-07-301-1/+1
| | | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Simon Rozman <simon@rozman.si>
* driver: remove useless defines from resourceJason A. Donenfeld2021-07-301-3/+0
| | | | | Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Simon Rozman <simon@rozman.si>
* api: upgradeSimon Rozman2021-07-2820-1382/+1538
| | | | Signed-off-by: Simon Rozman <simon@rozman.si>
* example: resolve signed/unsigned code analysis warningSimon Rozman2021-07-281-1/+1
| | | | Signed-off-by: Simon Rozman <simon@rozman.si>
* global: upgrade clang-formatSimon Rozman2021-07-281-24/+41
| | | | Signed-off-by: Simon Rozman <simon@rozman.si>
* vs: move shared configuration to wintun.props and upgradeSimon Rozman2021-07-2818-391/+229
| | | | | | | Remember to rename wintun.vcxproj.user file in your local working folder to wintun.props.user manually. Signed-off-by: Simon Rozman <simon@rozman.si>
* driver: workaround SDV failure with code analysisSimon Rozman2021-07-272-7/+9
| | | | | | | | | | | | | | SDV is using own CL.EXE which returns error code 2 when code analysis is turned on. However, we need code analysis results for DVL. While we could use a new "ReleaseSDV" configuration, we don't really require limited code analysis in Release builds, as long as we address all full code analysis warnings in Debug builds. To make DVL happier, an intermediate Release build was injected with code analysis turned on. Signed-off-by: Simon Rozman <simon@rozman.si>
* api: build with WDKJason A. Donenfeld2021-07-239-4/+33
| | | | | | | Makes builds more reproducable, as we can do our next release using the EWDK, an all-in-one ISO of build tools from Microsoft. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Copyright © 1996 – 2026 Jason A. Donenfeld. All Rights Reverse Engineered.