[ros-diffs] [tfaber] 61113: [SERIAL] - Fix a race condition

[tfaber]

Author: tfaber
Date: Thu Nov 28 14:32:04 2013
New Revision: 61113

URL: http://svn.reactos.org/svn/reactos?rev=61113&view=rev
Log:
[SERIAL]
- Fix a race condition

Modified:
    trunk/reactos/drivers/serial/serial/devctrl.c

Modified: trunk/reactos/drivers/serial/serial/devctrl.c
URL: 
http://svn.reactos.org/svn/reactos/trunk/reactos/drivers/serial/serial/devctrl.c?rev=61113&r1=61112&r2=61113&view=diff
==============================================================================
--- trunk/reactos/drivers/serial/serial/devctrl.c       [iso-8859-1] (original)
+++ trunk/reactos/drivers/serial/serial/devctrl.c       [iso-8859-1] Thu Nov 28 
14:32:04 2013
@@ -827,12 +827,10 @@
                                Status = STATUS_INVALID_PARAMETER;
                        else
                        {
-                               /* FIXME: Race condition here:
-                                * If an interrupt comes before we can mark the 
Irp
-                                * as pending, it might be possible to complete 
the
-                                * Irp before pending it, leading to a crash! */
+                               IoMarkIrpPending(Irp);
+
                                WaitingIrp = InterlockedCompareExchangePointer(
-                                       (PVOID)&DeviceExtension->WaitOnMaskIrp,
+                                       &DeviceExtension->WaitOnMaskIrp,
                                        Irp,
                                        NULL);
 
@@ -841,13 +839,11 @@
                                {
                                        /* Unable to have a 2nd pending IRP for 
this IOCTL */
                                        WARN_(SERIAL, "Unable to pend a second 
IRP for IOCTL_SERIAL_WAIT_ON_MASK\n");
-                                       Status = STATUS_INVALID_PARAMETER;
+                                       Irp->IoStatus.Information = 0;
+                                       Irp->IoStatus.Status = 
STATUS_INVALID_PARAMETER;
+                                       IoCompleteRequest(Irp, IO_NO_INCREMENT);
                                }
-                               else
-                               {
-                                       Status = STATUS_PENDING;
-                                       /* FIXME: immediately return if a wait 
event already occurred */
-                               }
+                               return STATUS_PENDING;
                        }
                        break;
                }