Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 1e5a15d6 authored by Ander Conselvan de Oliveira's avatar Ander Conselvan de Oliveira Committed by Chris Wilson
Browse files

drm/i915: Avoid drm_atomic_state_put(NULL) on error paths 



The error paths in hsw_trans_edp_pipe_A_crc_wa() and
intel_prepare_reset() would potentially call drm_atomic_state_put with a
NULL state, which would lead to a NULL pointer dereference.

Found by coverity.

v2: Improve the error paths. (Chris)

Fixes: 0853695c ("drm: Add reference counting to drm_atomic_state")
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.10-rc1+
Signed-off-by: default avatarAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1484742868-9551-1-git-send-email-ander.conselvan.de.oliveira@intel.com


Reviewed-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
parent 3c5e37f1

drivers/gpu/drm/i915/intel_display.c

+3 −7
Original line number Diff line number Diff line
@@ -3560,23 +3560,19 @@ void intel_prepare_reset(struct drm_i915_private *dev_priv) 
	state = drm_atomic_helper_duplicate_state(dev, ctx);

	if (IS_ERR(state)) {

		ret = PTR_ERR(state);

		state = NULL;

		DRM_ERROR("Duplicating state failed with %i\n", ret);

		goto err;

		return;

	}



	ret = drm_atomic_helper_disable_all(dev, ctx);

	if (ret) {

		DRM_ERROR("Suspending crtc's failed with %i\n", ret);

		goto err;

		drm_atomic_state_put(state);

		return;

	}



	dev_priv->modeset_restore_state = state;

	state->acquire_ctx = ctx;

	return;



err:

	drm_atomic_state_put(state);

}



void intel_finish_reset(struct drm_i915_private *dev_priv)

drivers/gpu/drm/i915/intel_pipe_crc.c

+6 −4
Original line number Diff line number Diff line
@@ -560,14 +560,14 @@ static void hsw_trans_edp_pipe_A_crc_wa(struct drm_i915_private *dev_priv, 
	state = drm_atomic_state_alloc(dev);

	if (!state) {

		ret = -ENOMEM;

		goto out;

		goto unlock;

	}



	state->acquire_ctx = drm_modeset_legacy_acquire_ctx(&crtc->base);

	pipe_config = intel_atomic_get_crtc_state(state, crtc);

	if (IS_ERR(pipe_config)) {

		ret = PTR_ERR(pipe_config);

		goto out;

		goto put_state;

	}



	pipe_config->pch_pfit.force_thru = enable;
@@ -576,10 +576,12 @@ static void hsw_trans_edp_pipe_A_crc_wa(struct drm_i915_private *dev_priv, 
		pipe_config->base.connectors_changed = true;



	ret = drm_atomic_commit(state);

out:



put_state:

	drm_atomic_state_put(state);

unlock:

	WARN(ret, "Toggling workaround to %i returns %i\n", enable, ret);

	drm_modeset_unlock_all(dev);

	drm_atomic_state_put(state);

}



static int ivb_pipe_crc_ctl_reg(struct drm_i915_private *dev_priv,