On Sun, Apr 07, 2024 at 02:30:53PM +0800, Huai-Yuan Liu wrote: > In malidp_mw_connector_reset, new memory is allocated with kzalloc, but > no check is performed. In order to prevent null pointer dereferencing, > ensure that mw_state is checked before calling > __drm_atomic_helper_connector_reset. > > Fixes: 8cbc5caf36ef ("drm: mali-dp: Add writeback connector") > Signed-off-by: Huai-Yuan Liu <qq810974084@xxxxxxxxx> Reviewed-by: Liviu Dudau <liviu.dudau@xxxxxxx> Thanks for the patch. I will pull it into drm-misc-fixes before the end of the week. Best regards, Liviu > --- > V2: > * In patch V2, we additionally set connector->state to NULL. In this way > we can ensure that there is no state pointing to freed memory. > Thanks to Liviu Dudau for helpful suggestion. > --- > drivers/gpu/drm/arm/malidp_mw.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/arm/malidp_mw.c b/drivers/gpu/drm/arm/malidp_mw.c > index 626709bec6f5..2577f0cef8fc 100644 > --- a/drivers/gpu/drm/arm/malidp_mw.c > +++ b/drivers/gpu/drm/arm/malidp_mw.c > @@ -72,7 +72,10 @@ static void malidp_mw_connector_reset(struct drm_connector *connector) > __drm_atomic_helper_connector_destroy_state(connector->state); > > kfree(connector->state); > - __drm_atomic_helper_connector_reset(connector, &mw_state->base); > + connector->state = NULL; > + > + if (mw_state) > + __drm_atomic_helper_connector_reset(connector, &mw_state->base); > } > > static enum drm_connector_status > -- > 2.34.1 > -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯