Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx> Will push to the appropriate branch in a bit, thanks! On Mon, 2022-05-23 at 13:35 +0200, Mark Menzynski wrote: > Resources needed for output poll workers are destroyed in > nouveau_fbcon_fini() before output poll workers are cleared in > nouveau_display_fini(). This means there is a time between fbcon_fini() > and display_fini(), where if output poll happens, it crashes. > > This patch introduces another output poll clearing before fbcon > resources are destroyed. > > BUG: KASAN: use-after-free in > __drm_fb_helper_initial_config_and_unlock.cold+0x1f3/0x291 > [drm_kms_helper] > > Cc: Ben Skeggs <bskeggs@xxxxxxxxxx> > Cc: Karol Herbst <kherbst@xxxxxxxxxx> > Cc: Lyude Paul <lyude@xxxxxxxxxx> > Cc: David Airlie <airlied@xxxxxxxx> > Cc: Daniel Vetter <daniel@xxxxxxxx> > Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx > Cc: nouveau@xxxxxxxxxxxxxxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx > Signed-off-by: Mark Menzynski <mmenzyns@xxxxxxxxxx> > --- > drivers/gpu/drm/nouveau/nouveau_fbcon.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/gpu/drm/nouveau/nouveau_fbcon.c > b/drivers/gpu/drm/nouveau/nouveau_fbcon.c > index 4f9b3aa5deda..5226323e55d3 100644 > --- a/drivers/gpu/drm/nouveau/nouveau_fbcon.c > +++ b/drivers/gpu/drm/nouveau/nouveau_fbcon.c > @@ -39,6 +39,7 @@ > > #include <drm/drm_crtc.h> > #include <drm/drm_crtc_helper.h> > +#include <drm/drm_probe_helper.h> > #include <drm/drm_fb_helper.h> > #include <drm/drm_fourcc.h> > #include <drm/drm_atomic.h> > @@ -605,6 +606,7 @@ nouveau_fbcon_fini(struct drm_device *dev) > if (!drm->fbcon) > return; > > + drm_kms_helper_poll_fini(dev); > nouveau_fbcon_accel_fini(dev); > nouveau_fbcon_destroy(dev, drm->fbcon); > kfree(drm->fbcon); -- Cheers, Lyude Paul (she/her) Software Engineer at Red Hat
