diff --git a/reactos/ntoskrnl/io/iomgr/irp.c b/reactos/ntoskrnl/io/iomgr/irp.c
index 0d445bb1abb..c682624599f 100644
--- a/reactos/ntoskrnl/io/iomgr/irp.c
+++ b/reactos/ntoskrnl/io/iomgr/irp.c
@@ -691,7 +691,7 @@ IoBuildAsynchronousFsdRequest(IN ULONG MajorFunction,
 				MmProbeAndLockPages(Irp->MdlAddress,
 									KernelMode,
 									MajorFunction == IRP_MJ_READ ?
-									IoWriteAccess : IoReadAccess);
+									IoReadAccess : IoWriteAccess);
 			}
 			_SEH_HANDLE
 			{