From: Shawn Hoffman <godisgovernment@gmail.com>
To: wireguard@lists.zx2c4.com
Subject: Re: [PATCH 2/3] use ExEnterCriticalRegionAndAcquireResourceExclusive and ExReleaseResourceAndLeaveCriticalRegion
Date: Sat, 25 Apr 2020 20:52:53 -0700 [thread overview]
Message-ID: <CAPqQDTDPUH17QUQG4xehfiM9zFGw7PVQu=u00v5x15ts=L7SVQ@mail.gmail.com> (raw)
In-Reply-To: <20200424234327.1814-2-godisgovernment@gmail.com>
Looking back over this, the enter+acquire of the existing code is
shared here, so replacing with exclusive will change behavior.
For now, please ignore this patch.
On Fri, Apr 24, 2020 at 4:44 PM Shawn Hoffman <godisgovernment@gmail.com> wrote:
>
> Signed-off-by: Shawn Hoffman <godisgovernment@gmail.com>
> ---
> wintun.c | 12 ++++--------
> 1 file changed, 4 insertions(+), 8 deletions(-)
>
> diff --git a/wintun.c b/wintun.c
> index 90e7930..00ac378 100644
> --- a/wintun.c
> +++ b/wintun.c
> @@ -884,15 +884,13 @@ TunDispatchDeviceControl(DEVICE_OBJECT *DeviceObject, IRP *Irp)
> switch (Stack->Parameters.DeviceIoControl.IoControlCode)
> {
> case TUN_IOCTL_REGISTER_RINGS: {
> - KeEnterCriticalRegion();
> - ExAcquireResourceSharedLite(&TunDispatchCtxGuard, TRUE);
> + ExEnterCriticalRegionAndAcquireResourceExclusive(&TunDispatchCtxGuard);
> #pragma warning(suppress : 28175)
> TUN_CTX *Ctx = DeviceObject->Reserved;
> Status = NDIS_STATUS_ADAPTER_NOT_READY;
> if (Ctx)
> Status = TunRegisterBuffers(Ctx, Irp);
> - ExReleaseResourceLite(&TunDispatchCtxGuard);
> - KeLeaveCriticalRegion();
> + ExReleaseResourceAndLeaveCriticalRegion(&TunDispatchCtxGuard);
> break;
> }
> case TUN_IOCTL_FORCE_CLOSE_HANDLES:
> @@ -913,14 +911,12 @@ _Use_decl_annotations_
> static NTSTATUS
> TunDispatchClose(DEVICE_OBJECT *DeviceObject, IRP *Irp)
> {
> - KeEnterCriticalRegion();
> - ExAcquireResourceSharedLite(&TunDispatchCtxGuard, TRUE);
> + ExEnterCriticalRegionAndAcquireResourceExclusive(&TunDispatchCtxGuard);
> #pragma warning(suppress : 28175)
> TUN_CTX *Ctx = DeviceObject->Reserved;
> if (Ctx)
> TunUnregisterBuffers(Ctx, IoGetCurrentIrpStackLocation(Irp)->FileObject);
> - ExReleaseResourceLite(&TunDispatchCtxGuard);
> - KeLeaveCriticalRegion();
> + ExReleaseResourceAndLeaveCriticalRegion(&TunDispatchCtxGuard);
> return NdisDispatchClose(DeviceObject, Irp);
> }
>
> --
> 2.26.2.windows.1
>
next prev parent reply other threads:[~2020-04-26 3:53 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-24 23:43 [PATCH 1/3] fix possible TunDispatchSecurityDescriptor leak Shawn Hoffman
2020-04-24 23:43 ` [PATCH 2/3] use ExEnterCriticalRegionAndAcquireResourceExclusive and ExReleaseResourceAndLeaveCriticalRegion Shawn Hoffman
2020-04-26 3:52 ` Shawn Hoffman [this message]
2020-10-30 16:05 ` Jason A. Donenfeld
2020-04-24 23:43 ` [PATCH 3/3] use RtlSubAuthoritySid instead of directly poking SID Shawn Hoffman
2020-10-30 15:59 ` Jason A. Donenfeld
2020-10-30 16:05 ` [PATCH 1/3] fix possible TunDispatchSecurityDescriptor leak Jason A. Donenfeld
-- strict thread matches above, loose matches on Subject: below --
2020-04-24 18:59 [PATCH 0/3] misc code cleanup Shawn Hoffman
2020-04-24 18:59 ` [PATCH 2/3] use ExEnterCriticalRegionAndAcquireResourceExclusive and ExReleaseResourceAndLeaveCriticalRegion Shawn Hoffman
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