[PATCH xf86-video-ati 0/6] Harden against other DRM masters

[Michel Dänzer]

From: Michel Dänzer <michel.daenzer at amd.com>

While our VT is inactive, so we aren't DRM master, other processes can
become DRM master. A DRM master can access any KMS framebuffer (FB) by
guessing its handle (in practice, it should be easy to find all existing
FBs by brute-forcing through a relatively small number of handles).

This series makes us destroy all FBs created by this driver before
leaving our VT, except for an all-black one created especially for this
purpose. This closes a long-standing potential information leak, which
was made worse by reference-counting the FBs we create.

Patches 1-4 are preparatory. The meat is in patch 5. Patch 6 removes a
function which is no longer used with patch 5.

Michel Dänzer (6):
  Create radeon_pixmap_clear helper
  Create drmmode_set_mode helper
  Create radeon_pixmap_get_fb_ptr helper
  Create radeon_master_screen helper
  Make all active CRTCs scan out an all-black framebuffer in LeaveVT
  Remove drmmode_scanout_free

 src/drmmode_display.c  | 112 +++++++++++++++++++++++--------------------------
 src/drmmode_display.h  |   8 +++-
 src/radeon.h           |  67 ++++++++++++++++-------------
 src/radeon_bo_helper.c |  21 ++++++++++
 src/radeon_bo_helper.h |   3 ++
 src/radeon_kms.c       |  98 ++++++++++++++++++++++++++++++++++++++++---
 6 files changed, 214 insertions(+), 95 deletions(-)

-- 
2.14.1