[WIN32K:NTUSER] Fix WIN32K BSOD mentioned in CORE-15027
authorJoachim Henze <Joachim.Henze@reactos.org>
Fri, 21 Sep 2018 01:04:31 +0000 (03:04 +0200)
committerJoachim Henze <Joachim.Henze@reactos.org>
Fri, 21 Sep 2018 01:04:31 +0000 (03:04 +0200)
commitef016bfe0a9dc3cc7924671277b44884e39d89d5
treea2c197e82f1a40861fbd02f7e9c64da39ce959ec
parentf8f83d4d4d4b1ccb62a3bdc931bc62466932d925
[WIN32K:NTUSER] Fix WIN32K BSOD mentioned in CORE-15027

Fixes accessing nullptr / invalid handle in Window->SystemMenu
I could trigger this occasionally when moving Opera 12.18 window
in front of Spotify 1.0.29.92 window.

Fix was:
authored by Thomas Faber (Thank you!)
tested by me
reviewed by James Tabor
win32ss/user/ntuser/menu.c