diff --git a/dlls/ntoskrnl.exe/ntoskrnl.c b/dlls/ntoskrnl.exe/ntoskrnl.c
index a3dd7b93621..18b17f89fd8 100644
--- a/dlls/ntoskrnl.exe/ntoskrnl.c
+++ b/dlls/ntoskrnl.exe/ntoskrnl.c
@@ -3911,3 +3911,12 @@ ULONG WINAPI ExSetTimerResolution(ULONG time, BOOLEAN set_resolution)
     FIXME("stub: %u %d\n", time, set_resolution);
     return KeQueryTimeIncrement();
 }
+
+/***********************************************************************
+ *           IoGetRequestorProcess   (NTOSKRNL.EXE.@)
+ */
+PEPROCESS WINAPI IoGetRequestorProcess(IRP *irp)
+{
+    TRACE("irp %p.\n", irp);
+    return irp->Tail.Overlay.Thread->kthread.process;
+}
diff --git a/dlls/ntoskrnl.exe/ntoskrnl.exe.spec b/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
index 88c1a06cbeb..ddc3f72b8e3 100644
--- a/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
+++ b/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
@@ -406,7 +406,7 @@
 @ stub IoGetInitialStack
 @ stub IoGetLowerDeviceObject
 @ stdcall IoGetRelatedDeviceObject(ptr)
-@ stub IoGetRequestorProcess
+@ stdcall IoGetRequestorProcess(ptr)
 @ stub IoGetRequestorProcessId
 @ stub IoGetRequestorSessionId
 @ stdcall IoGetStackLimits(ptr ptr)
diff --git a/dlls/ntoskrnl.exe/tests/driver.c b/dlls/ntoskrnl.exe/tests/driver.c
index 6ab3c622aec..0506011ce56 100644
--- a/dlls/ntoskrnl.exe/tests/driver.c
+++ b/dlls/ntoskrnl.exe/tests/driver.c
@@ -225,6 +225,8 @@ static void test_irp_struct(IRP *irp, DEVICE_OBJECT *device)
     ok(!irp->UserEvent, "UserEvent = %p\n", irp->UserEvent);
     ok(irp->Tail.Overlay.Thread == (PETHREAD)KeGetCurrentThread(),
        "IRP thread is not the current thread\n");
+
+    ok(IoGetRequestorProcess(irp) == IoGetCurrentProcess(), "processes didn't match\n");
 }
 
 static void test_mdl_map(void)
diff --git a/include/ddk/ntifs.h b/include/ddk/ntifs.h
index b287b067992..39636e80730 100644
--- a/include/ddk/ntifs.h
+++ b/include/ddk/ntifs.h
@@ -131,6 +131,7 @@ typedef struct _FS_FILTER_CALLBACKS
 
 BOOLEAN WINAPI FsRtlIsNameInExpression(PUNICODE_STRING, PUNICODE_STRING, BOOLEAN, PWCH);
 DEVICE_OBJECT * WINAPI IoGetAttachedDevice(DEVICE_OBJECT*);
+PEPROCESS WINAPI IoGetRequestorProcess(IRP*);
 NTSTATUS WINAPI ObOpenObjectByPointer(void*,ULONG,PACCESS_STATE,ACCESS_MASK,POBJECT_TYPE,KPROCESSOR_MODE,HANDLE*);
 NTSTATUS WINAPI ObQueryNameString(PVOID,POBJECT_NAME_INFORMATION,ULONG,PULONG);
 BOOLEAN WINAPI PsIsSystemThread(PETHREAD);