branch update for HEAD-2003050101

[reactos.git] / ntoskrnl / io / lock.c

diff --git a/ntoskrnl/io/lock.c b/ntoskrnl/io/lock.c
index 38cdd61..3b14693 100644 (file)
--- a/ntoskrnl/io/lock.c
+++ b/ntoskrnl/io/lock.c
@@ -58,6 +58,7 @@ NtLockFile (
        IO_STATUS_BLOCK         LocalIoStatusBlock;
        PIO_STATUS_BLOCK IoStatusBlock;
        PDEVICE_OBJECT  DeviceObject;
+   ULONG FobFlags;
 
        //FIXME: instead of this, use SEH when available?
        if (!Length || !ByteOffset)     {
@@ -65,13 +66,9 @@ NtLockFile (
                goto fail;
        }
 
-       /*
-       BUGBUG: ObReferenceObjectByHandle fails if DesiredAccess=0 and mode=UserMode!
-       It should ONLY fail if we desire an access that conflict with granted access!
-       */
        Status = ObReferenceObjectByHandle(
                                         FileHandle,
-                                    FILE_READ_DATA,//BUGBUG: have to use something...but shouldn't have to!
+                                    0,
                                     IoFileObjectType,
                                     ExGetPreviousMode(),
                                     (PVOID*)&FileObject,
@@ -127,7 +124,6 @@ NtLockFile (
        StackPtr = IoGetNextIrpStackLocation(Irp);
        StackPtr->MajorFunction = IRP_MJ_LOCK_CONTROL;
        StackPtr->MinorFunction = IRP_MN_LOCK;
-       StackPtr->DeviceObject = DeviceObject;
        StackPtr->FileObject = FileObject;
        
        if (ExclusiveLock) StackPtr->Flags |= SL_EXCLUSIVE_LOCK;
@@ -157,15 +153,17 @@ NtLockFile (
                                        TRUE,  
                                        TRUE  );
 
+   //can't touch FileObject after IoCallDriver since it might be freed
+   FobFlags = FileObject->Flags;
        Status = IofCallDriver(DeviceObject, Irp);
 
-       if (Status == STATUS_PENDING && (FileObject->Flags & FO_SYNCHRONOUS_IO)) {
+   if (Status == STATUS_PENDING && (FobFlags & FO_SYNCHRONOUS_IO)) {
 
                Status = KeWaitForSingleObject(
                                                        Event,
                                                        Executive,
                                                        ExGetPreviousMode() , 
-                                                       (FileObject->Flags & FO_ALERTABLE_IO) ? TRUE : FALSE,
+                     (FobFlags & FO_ALERTABLE_IO) ? TRUE : FALSE,
                                                        NULL
                                                        );
 
@@ -181,7 +179,7 @@ NtLockFile (
                Status = LocalIoStatusBlock.Status;
        }
 
-       if (FileObject->Flags & FO_SYNCHRONOUS_IO)
+   if (FobFlags & FO_SYNCHRONOUS_IO)
                *UserIoStatusBlock = LocalIoStatusBlock;
 
        return Status;