mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

drm/simple_kms_helper: Fix NULL pointer dereference with no active CRTC 

It is possible that drm_simple_kms_plane_atomic_check called
with no CRTC set, e.g. when user-space application sets CRTC_ID/FB_ID
to 0 before doing any actual drawing. This leads to NULL pointer
dereference because in this case new CRTC state is NULL and must be
checked before accessing.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1519279759-7803-1-git-send-email-andr2000@gmail.com
This commit is contained in:
Oleksandr Andrushchenko 2018-02-22 08:09:19 +02:00 committed by Daniel Vetter
parent 35152d1159
commit 4751cf733a
1 changed files with 3 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
drivers/gpu/drm/drm_simple_kms_helper.c
View File

@ -112,12 +112,6 @@ static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane,
pipe = container_of(plane, struct drm_simple_display_pipe, plane);
crtc_state = drm_atomic_get_new_crtc_state(plane_state->state,
&pipe->crtc);
if (!crtc_state->enable)
return 0; /* nothing to check when disabling or disabled */
if (crtc_state->enable)
drm_mode_get_hv_timing(&crtc_state->mode,
&clip.x2, &clip.y2);
ret = drm_atomic_helper_check_plane_state(plane_state, crtc_state,
&clip,
@ -128,7 +122,9 @@ static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane,
return ret;
if (!plane_state->visible)
return -EINVAL;
return 0;
drm_mode_get_hv_timing(&crtc_state->mode, &clip.x2, &clip.y2);
if (!pipe->funcs || !pipe->funcs->check)
return 0;