https://git.reactos.org/?p=reactos.git;a=commitdiff;h=9ee9f733694243a81fb458cfc11edbdc3bdfc835
commit 9ee9f733694243a81fb458cfc11edbdc3bdfc835
Author: Joachim Henze <joachim.he...@reactos.org>
AuthorDate: Sun Apr 2 16:27:42 2023 +0200
Commit: GitHub <nore...@github.com>
CommitDate: Sun Apr 2 23:27:42 2023 +0900
[NTUSER] Fix BSOD 0x1E nullptr deref CORE-18899 (#5212)
fix authored by JIRA-user "TANGaming". I do suspect that the possibility of
that nullptr deref was introduced on the master branch by 0.4.13-dev-962-g
4193b8d. Doug Lyons signalled his "ok" regarding the fix in chat already.
CORE-18899
---
win32ss/user/ntuser/defwnd.c | 15 +++++++++------
win32ss/user/ntuser/event.c | 3 +--
win32ss/user/ntuser/hook.c | 7 +++----
3 files changed, 13 insertions(+), 12 deletions(-)
diff --git a/win32ss/user/ntuser/defwnd.c b/win32ss/user/ntuser/defwnd.c
index 81ece247b78..de4b4e12e18 100644
--- a/win32ss/user/ntuser/defwnd.c
+++ b/win32ss/user/ntuser/defwnd.c
@@ -1,9 +1,8 @@
/*
- * COPYRIGHT: See COPYING in the top level directory
- * PROJECT: ReactOS Win32k subsystem
- * PURPOSE: Miscellaneous User functions
- * FILE: win32ss/user/ntuser/defwnd.c
- * PROGRAMER:
+ * PROJECT: ReactOS Win32k subsystem
+ * LICENSE: See COPYING in the top level directory
+ * PURPOSE: Miscellaneous User functions
+ * COPYRIGHT: 2008-2020 James Tabor <james.ta...@reactos.org>
*/
#include <win32k.h>
@@ -797,6 +796,10 @@ IntDefWindowProc(
HWND hwndTop = UserGetForegroundWindow();
PWND topWnd = UserGetWindowObject(hwndTop);
+ // MS Doc: foreground window can be NULL, e.g. when window is
losing activation
+ if (!topWnd)
+ return 0;
+
// We want to forbid snapping operations on the TaskBar
// We use a heuristic for detecting the TaskBar Wnd by its typical
Style & ExStyle Values
ExStyleTB = (topWnd->ExStyle & WS_EX_TOOLWINDOW);
@@ -805,7 +808,7 @@ IntDefWindowProc(
&& (ExStyleTB == WS_EX_TOOLWINDOW);
TRACE("ExStyle=%x Style=%x IsTaskBar=%d\n", ExStyleTB, StyleTB,
IsTaskBar);
- if (topWnd && !IsTaskBar)
+ if (!IsTaskBar)
{
if ((topWnd->style & WS_THICKFRAME) == 0)
return 0;
diff --git a/win32ss/user/ntuser/event.c b/win32ss/user/ntuser/event.c
index f5a3a65c3bc..b52efe9389e 100644
--- a/win32ss/user/ntuser/event.c
+++ b/win32ss/user/ntuser/event.c
@@ -2,8 +2,7 @@
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS kernel
* PURPOSE: Window event handlers
- * FILE: win32ss/user/ntuser/event.c
- * PROGRAMER: James Tabor (james.ta...@rectos.org)
+ * PROGRAMER: James Tabor <james.ta...@reactos.org>
*/
#include <win32k.h>
diff --git a/win32ss/user/ntuser/hook.c b/win32ss/user/ntuser/hook.c
index 792d195470a..8f82d5b2f46 100644
--- a/win32ss/user/ntuser/hook.c
+++ b/win32ss/user/ntuser/hook.c
@@ -2,10 +2,9 @@
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS kernel
* PURPOSE: Window hooks
- * FILE: win32ss/user/ntuser/hook.c
- * PROGRAMER: Casper S. Hornstrup (cho...@users.sourceforge.net)
- * James Tabor (james.ta...@rectos.org)
- * Rafal Harabien (raf...@reactos.org)
+ * PROGRAMER: Casper S. Hornstrup <cho...@users.sourceforge.net>
+ * James Tabor <james.ta...@reactos.org>
+ * Rafal Harabien <raf...@reactos.org>
* NOTE: Most of this code was adapted from Wine,
* Copyright (C) 2002 Alexandre Julliard
*/
