<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - vmwgfx null ptr dereference at vmw_screen_ioctl.c:76 due to ioctl failure" href="https://bugs.freedesktop.org/show_bug.cgi?id=91098#c1">Comment # 1</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - vmwgfx null ptr dereference at vmw_screen_ioctl.c:76 due to ioctl failure" href="https://bugs.freedesktop.org/show_bug.cgi?id=91098">bug 91098</a> from <a class="email" href="mailto:thellstrom@vmware.com" title="Thomas Hellström <thellstrom@vmware.com>"> Thomas Hellström</a> <pre>Hi. Thanks for the bug report. I think the root problem is gnome-shell(gdm) dropping its master privileges and then trying to render. The reason this is not allowed in the vmwgfx driver is the following scenario: 1) A user switches away the X server VT and gets a console terminal. 2) User launches a DRM-aware malicious app that becomes master and authenticates itself. 3) The user switches back the X server 4) The malicious app can now open exported buffer objects at will and access or manipulate user private data. This is correctly blocked in the vmwgfx driver. So this is AFAICT a gnome-shell (gdm mode) bug. It shouldn't render when it drops its master privileges, so the gnome bugzilla would be good to start with. We'll follow up.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are the assignee for the bug.</li> </ul> </body> </html>