| Message ID | 20180530004259.GA7981@haneen-vb (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, May 30, 2018 at 03:42:59AM +0300, Haneen Mohammed wrote: > This patch add checks for NULL drm_[connector/crtc/plane]_helper_funcs > pointers before derefrencing the variable to avoid NULL pointer > dereference and make the helper functions optional in the following > cases: > > 1) when using drm_helper_probe_single_connector_modes for fill_modes > callback in the drm_connector_funcs. > 2) using drm_atomic_helper_[check/commit] for atomic_[check/commit] > callbacks in the drm_mode_config_funcs. > > The dependency is as follow: > > drm_connector_funcs: > * fill_modes = drm_helper_probe_single_connector_modes > b) drm_helper_probe_detect -> drm_connector_helper_funcs > > drm_mode_config_funcs: > * atomic_check = drm_atomic_helper_check > a) drm_atomic_helper_check_modeset -> drm_connector helper_funcs > a) handle_conflicting_encoders -> drm_connector_helper_funcs > b) mode_fixup -> drm_crtc_helper_funcs > c) update_connector_routing -> drm_connectot_helper_funcs > > * atomic_commit = drm_atomic_helper_commit > a) drm_atomic_helper_prepare_planes -> drm_plane_helper_funcs > b) drm_atomic_helper_cleanup_planes -> drm_plane_helper_funcs > > Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com> Ok, I think making drm_connector_helper_funcs optional makes some sense - ->best_connector has a default implemenation that works for almost everyone, and if you don't have a way to detect the output it's silly to have a default implementation that does nothing. But making the plane/crtc funcs optional gives you a driver which does exactly nothing, and that's not terribly useful. I think respinning this to just make drm_connector_helper_funcs optional is reasonable, and for all others we need to start making vkms functional :-) Cheers, Daniel > --- > Chanes in v2: > - add the least amount of checks to make the helpers optional for vkms > > drivers/gpu/drm/drm_atomic_helper.c | 16 ++++++++-------- > drivers/gpu/drm/drm_probe_helper.c | 5 +++-- > 2 files changed, 11 insertions(+), 10 deletions(-) > > diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > index 2a7ceca82b9e..ff3684c4a83c 100644 > --- a/drivers/gpu/drm/drm_atomic_helper.c > +++ b/drivers/gpu/drm/drm_atomic_helper.c > @@ -112,9 +112,9 @@ static int handle_conflicting_encoders(struct drm_atomic_state *state, > if (!new_conn_state->crtc) > continue; > > - if (funcs->atomic_best_encoder) > + if (funcs && funcs->atomic_best_encoder) > new_encoder = funcs->atomic_best_encoder(connector, new_conn_state); > - else if (funcs->best_encoder) > + else if (funcs && funcs->best_encoder) > new_encoder = funcs->best_encoder(connector); > else > new_encoder = drm_atomic_helper_best_encoder(connector); > @@ -308,10 +308,10 @@ update_connector_routing(struct drm_atomic_state *state, > > funcs = connector->helper_private; > > - if (funcs->atomic_best_encoder) > + if (funcs && funcs->atomic_best_encoder) > new_encoder = funcs->atomic_best_encoder(connector, > new_connector_state); > - else if (funcs->best_encoder) > + else if (funcs && funcs->best_encoder) > new_encoder = funcs->best_encoder(connector); > else > new_encoder = drm_atomic_helper_best_encoder(connector); > @@ -438,7 +438,7 @@ mode_fixup(struct drm_atomic_state *state) > continue; > > funcs = crtc->helper_private; > - if (!funcs->mode_fixup) > + if (!funcs || !funcs->mode_fixup) > continue; > > ret = funcs->mode_fixup(crtc, &new_crtc_state->mode, > @@ -639,7 +639,7 @@ drm_atomic_helper_check_modeset(struct drm_device *dev, > new_crtc_state->connectors_changed = true; > } > > - if (funcs->atomic_check) > + if (funcs && funcs->atomic_check) > ret = funcs->atomic_check(connector, new_connector_state); > if (ret) > return ret; > @@ -2117,7 +2117,7 @@ int drm_atomic_helper_prepare_planes(struct drm_device *dev, > > funcs = plane->helper_private; > > - if (funcs->prepare_fb) { > + if (funcs && funcs->prepare_fb) { > ret = funcs->prepare_fb(plane, new_plane_state); > if (ret) > goto fail; > @@ -2412,7 +2412,7 @@ void drm_atomic_helper_cleanup_planes(struct drm_device *dev, > > funcs = plane->helper_private; > > - if (funcs->cleanup_fb) > + if (funcs && funcs->cleanup_fb) > funcs->cleanup_fb(plane, plane_state); > } > } > diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c > index 527743394150..2fea54d16ebb 100644 > --- a/drivers/gpu/drm/drm_probe_helper.c > +++ b/drivers/gpu/drm/drm_probe_helper.c > @@ -320,7 +320,7 @@ drm_helper_probe_detect(struct drm_connector *connector, > if (ret) > return ret; > > - if (funcs->detect_ctx) > + if (funcs && funcs->detect_ctx) > return funcs->detect_ctx(connector, ctx, force); > else if (connector->funcs->detect) > return connector->funcs->detect(connector, force); > @@ -480,7 +480,8 @@ int drm_helper_probe_single_connector_modes(struct drm_connector *connector, > goto prune; > } > > - count = (*connector_funcs->get_modes)(connector); > + if (connector_funcs && connector_funcs->get_modes) > + count = (*connector_funcs->get_modes)(connector); > > if (count == 0 && connector->status == connector_status_connected) > count = drm_add_modes_noedid(connector, 1024, 768); > -- > 2.17.0 >
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 2a7ceca82b9e..ff3684c4a83c 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -112,9 +112,9 @@ static int handle_conflicting_encoders(struct drm_atomic_state *state, if (!new_conn_state->crtc) continue; - if (funcs->atomic_best_encoder) + if (funcs && funcs->atomic_best_encoder) new_encoder = funcs->atomic_best_encoder(connector, new_conn_state); - else if (funcs->best_encoder) + else if (funcs && funcs->best_encoder) new_encoder = funcs->best_encoder(connector); else new_encoder = drm_atomic_helper_best_encoder(connector); @@ -308,10 +308,10 @@ update_connector_routing(struct drm_atomic_state *state, funcs = connector->helper_private; - if (funcs->atomic_best_encoder) + if (funcs && funcs->atomic_best_encoder) new_encoder = funcs->atomic_best_encoder(connector, new_connector_state); - else if (funcs->best_encoder) + else if (funcs && funcs->best_encoder) new_encoder = funcs->best_encoder(connector); else new_encoder = drm_atomic_helper_best_encoder(connector); @@ -438,7 +438,7 @@ mode_fixup(struct drm_atomic_state *state) continue; funcs = crtc->helper_private; - if (!funcs->mode_fixup) + if (!funcs || !funcs->mode_fixup) continue; ret = funcs->mode_fixup(crtc, &new_crtc_state->mode, @@ -639,7 +639,7 @@ drm_atomic_helper_check_modeset(struct drm_device *dev, new_crtc_state->connectors_changed = true; } - if (funcs->atomic_check) + if (funcs && funcs->atomic_check) ret = funcs->atomic_check(connector, new_connector_state); if (ret) return ret; @@ -2117,7 +2117,7 @@ int drm_atomic_helper_prepare_planes(struct drm_device *dev, funcs = plane->helper_private; - if (funcs->prepare_fb) { + if (funcs && funcs->prepare_fb) { ret = funcs->prepare_fb(plane, new_plane_state); if (ret) goto fail; @@ -2412,7 +2412,7 @@ void drm_atomic_helper_cleanup_planes(struct drm_device *dev, funcs = plane->helper_private; - if (funcs->cleanup_fb) + if (funcs && funcs->cleanup_fb) funcs->cleanup_fb(plane, plane_state); } } diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c index 527743394150..2fea54d16ebb 100644 --- a/drivers/gpu/drm/drm_probe_helper.c +++ b/drivers/gpu/drm/drm_probe_helper.c @@ -320,7 +320,7 @@ drm_helper_probe_detect(struct drm_connector *connector, if (ret) return ret; - if (funcs->detect_ctx) + if (funcs && funcs->detect_ctx) return funcs->detect_ctx(connector, ctx, force); else if (connector->funcs->detect) return connector->funcs->detect(connector, force); @@ -480,7 +480,8 @@ int drm_helper_probe_single_connector_modes(struct drm_connector *connector, goto prune; } - count = (*connector_funcs->get_modes)(connector); + if (connector_funcs && connector_funcs->get_modes) + count = (*connector_funcs->get_modes)(connector); if (count == 0 && connector->status == connector_status_connected) count = drm_add_modes_noedid(connector, 1024, 768);
This patch add checks for NULL drm_[connector/crtc/plane]_helper_funcs pointers before derefrencing the variable to avoid NULL pointer dereference and make the helper functions optional in the following cases: 1) when using drm_helper_probe_single_connector_modes for fill_modes callback in the drm_connector_funcs. 2) using drm_atomic_helper_[check/commit] for atomic_[check/commit] callbacks in the drm_mode_config_funcs. The dependency is as follow: drm_connector_funcs: * fill_modes = drm_helper_probe_single_connector_modes b) drm_helper_probe_detect -> drm_connector_helper_funcs drm_mode_config_funcs: * atomic_check = drm_atomic_helper_check a) drm_atomic_helper_check_modeset -> drm_connector helper_funcs a) handle_conflicting_encoders -> drm_connector_helper_funcs b) mode_fixup -> drm_crtc_helper_funcs c) update_connector_routing -> drm_connectot_helper_funcs * atomic_commit = drm_atomic_helper_commit a) drm_atomic_helper_prepare_planes -> drm_plane_helper_funcs b) drm_atomic_helper_cleanup_planes -> drm_plane_helper_funcs Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com> --- Chanes in v2: - add the least amount of checks to make the helpers optional for vkms drivers/gpu/drm/drm_atomic_helper.c | 16 ++++++++-------- drivers/gpu/drm/drm_probe_helper.c | 5 +++-- 2 files changed, 11 insertions(+), 10 deletions(-)