[PATCH 7/9] drm/msm/dpu: check for overflow in _dpu_crtc_setup_lm_bounds()

[Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>]

Check in _dpu_crtc_setup_lm_bounds() that CRTC width is not overflowing
LM requirements.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
index 64befead366f..2fc1c2729bfd 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
@@ -711,12 +711,13 @@ void dpu_crtc_complete_commit(struct drm_crtc *crtc)
 	_dpu_crtc_complete_flip(crtc);
 }
 
-static void _dpu_crtc_setup_lm_bounds(struct drm_crtc *crtc,
+static int _dpu_crtc_setup_lm_bounds(struct drm_crtc *crtc,
 		struct drm_crtc_state *state)
 {
 	struct dpu_crtc_state *cstate = to_dpu_crtc_state(state);
 	struct drm_display_mode *adj_mode = &state->adjusted_mode;
 	u32 crtc_split_width = adj_mode->hdisplay / cstate->num_mixers;
+	struct dpu_kms *dpu_kms = _dpu_crtc_get_kms(crtc);
 	int i;
 
 	for (i = 0; i < cstate->num_mixers; i++) {
@@ -727,7 +728,12 @@ static void _dpu_crtc_setup_lm_bounds(struct drm_crtc *crtc,
 		r->y2 = adj_mode->vdisplay;
 
 		trace_dpu_crtc_setup_lm_bounds(DRMID(crtc), i, r);
+
+		if (drm_rect_width(r) > dpu_kms->catalog->caps->max_mixer_width)
+			return -E2BIG;
 	}
+
+	return 0;
 }
 
 static void _dpu_crtc_get_pcc_coeff(struct drm_crtc_state *state,
@@ -1195,8 +1201,11 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
 	if (crtc_state->active_changed)
 		crtc_state->mode_changed = true;
 
-	if (cstate->num_mixers)
-		_dpu_crtc_setup_lm_bounds(crtc, crtc_state);
+	if (cstate->num_mixers) {
+		rc = _dpu_crtc_setup_lm_bounds(crtc, crtc_state);
+		if (rc)
+			return rc;
+	}
 
 	/* FIXME: move this to dpu_plane_atomic_check? */
 	drm_atomic_crtc_state_for_each_plane_state(plane, pstate, crtc_state) {

-- 
2.39.2