[PATCH 0/3] drm, drm/vmwgfx: fixes and updates related to drm_master

From: Desmond Cheong Zhi Xi
Date: Thu Jul 22 2021 - 05:30:09 EST


This series contains some improvements that Daniel Vetter proposed following a discussion on a recent series:

While preparing these patches, I also noticed some unprotected uses of drm_master in the vmwgfx driver that can be addressed by new functions from the previous series.

This series is thus broken up into three patches:

1. Switch from the outer drm_device.master_mutex to the inner drm_file.master_lookup_lock in drm_is_current_master.

2. Update the kerneldoc for lease fields in drm_master to clarify lifetime/locking rules.

3. Prevent potential use-after-free bugs by replacing calls to drm_master_get with drm_file_get_master in vmwgfx_surface.c.

Best wishes,

Desmond Cheong Zhi Xi (3):
drm: use the lookup lock in drm_is_current_master
drm: clarify lifetime/locking for drm_master's lease fields
drm/vmwgfx: fix potential UAF in vmwgfx_surface.c

drivers/gpu/drm/drm_auth.c | 9 ++--
drivers/gpu/drm/vmwgfx/vmwgfx_surface.c | 4 +-
include/drm/drm_auth.h | 62 ++++++++++++++++++++-----
3 files changed, 58 insertions(+), 17 deletions(-)