From: Maxime Ripard <maxime@cerno.tech> stable inclusion from stable-v5.10.137 commit c015d12317c503dff7fc8f20a6ae00be255cb1a3 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit e55a07751146ef8ebc2c561564437b78f46405d3 ] drm_atomic_helper_connector_reset uses kmalloc which, from an API standpoint, can fail, and thus setting connector->state to NULL. However, our reset hook then calls drm_atomic_helper_connector_tv_reset that will access connector->state without checking if it's a valid pointer or not. Make sure we don't end up accessing a NULL pointer. Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com> Suggested-by: Dave Stevenson <dave.stevenson@raspberrypi.com> Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://patchwork.freedesktop.org/patch/msgid/20201215154243.540115-5-maxime... Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Reviewed-by: Wei Li <liwei391@huawei.com> --- drivers/gpu/drm/vc4/vc4_hdmi.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index 9a90f22df3d2..978afe706ee2 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -209,7 +209,9 @@ static int vc4_hdmi_connector_get_modes(struct drm_connector *connector) static void vc4_hdmi_connector_reset(struct drm_connector *connector) { drm_atomic_helper_connector_reset(connector); - drm_atomic_helper_connector_tv_reset(connector); + + if (connector->state) + drm_atomic_helper_connector_tv_reset(connector); } static const struct drm_connector_funcs vc4_hdmi_connector_funcs = { -- 2.20.1