From: Alexandr Sapozhnikov alsp705@gmail.com
[ Upstream commit 7245e629dcaaf308f1868aeffa218e9849c77893 ]
After having been compared to NULL value at cirrus.c:455, pointer 'pipe->plane.state->fb' is passed as 1st parameter in call to function 'cirrus_fb_blit_rect' at cirrus.c:461, where it is dereferenced at cirrus.c:316.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
v2: * aligned commit message to line-length limits
Signed-off-by: Alexandr Sapozhnikov alsp705@gmail.com Reviewed-by: Thomas Zimmermann tzimmermann@suse.de Signed-off-by: Thomas Zimmermann tzimmermann@suse.de Link: https://patchwork.freedesktop.org/patch/msgid/20230215171549.16305-1-alsp705... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/tiny/cirrus.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/tiny/cirrus.c b/drivers/gpu/drm/tiny/cirrus.c index 4611ec408506b..2a81311b22172 100644 --- a/drivers/gpu/drm/tiny/cirrus.c +++ b/drivers/gpu/drm/tiny/cirrus.c @@ -450,7 +450,7 @@ static void cirrus_pipe_update(struct drm_simple_display_pipe *pipe, if (state->fb && cirrus->cpp != cirrus_cpp(state->fb)) cirrus_mode_set(cirrus, &crtc->mode, state->fb);
- if (drm_atomic_helper_damage_merged(old_state, state, &rect)) + if (state->fb && drm_atomic_helper_damage_merged(old_state, state, &rect)) cirrus_fb_blit_rect(state->fb, &shadow_plane_state->data[0], &rect); }