[PATCH 0/1] MR9502: ntoskrnl.exe: Open thread with MAXIMUM_ALLOWED access in KeGetCurrentThread().

[Paul Gofman (＠gofman)]

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/9502

[PATCH 1/1] ntoskrnl.exe: Open thread with MAXIMUM_ALLOWED access in KeGetCurrentThread().

[Paul Gofman]

From: Paul Gofman <pgofman(a)codeweavers.com>

---
 dlls/ntoskrnl.exe/ntoskrnl.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dlls/ntoskrnl.exe/ntoskrnl.c b/dlls/ntoskrnl.exe/ntoskrnl.c
index def86ca17e8..b3f45751b99 100644
--- a/dlls/ntoskrnl.exe/ntoskrnl.c
+++ b/dlls/ntoskrnl.exe/ntoskrnl.c
@@ -2571,7 +2571,7 @@ PRKTHREAD WINAPI KeGetCurrentThread(void)
 
         /* FIXME: we shouldn't need it, GetCurrentThread() should be client thread already */
         if (GetCurrentThreadId() == request_thread)
-            handle = OpenThread( THREAD_QUERY_INFORMATION, FALSE, client_tid );
+            handle = OpenThread( MAXIMUM_ALLOWED, FALSE, client_tid );
 
         kernel_object_from_handle( handle, PsThreadType, (void**)&thread );
         if (handle != GetCurrentThread()) NtClose( handle );
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/9502

[Paul Gofman (＠gofman)]

NASCAR 25 sets some DACLs to the game threads which result in failure to open those in KeGetCurrentThread() when processing a request (to Wine driver) issued by such a thread. Ideally we should not use user-mode handle open functions at all in ntoskrnl / drivers, but we don't yet have full kernel object access management and both ntoskrnl and Wine drivers resort to some user-mode things currently. kernel_object_from_handle() called after doesn't depend on any access rights on user thread handle.

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/9502#note_122670