[PATCH] SWDEV-476969 - dm/amdgpu: Fail dm_atomic_check if cursor overlay is required at MAX_SURFACES

[Zaeem Mohamed]

[why]
Prevent index-out-of-bounds due to requiring cursor overlay when
plane_count is MAX_SURFACES.

[how]
Bounds check on plane_count when requiring overlay cursor.

Co-developed-by: Melissa Wen <m...@igalia.com>
Signed-off-by: Zaeem Mohamed <zaeem.moha...@amd.com>
---
 amdgpu_dm/amdgpu_dm.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/amdgpu_dm/amdgpu_dm.c b/amdgpu_dm/amdgpu_dm.c
index 97e0a1bbba..964497c613 100644
--- a/amdgpu_dm/amdgpu_dm.c
+++ b/amdgpu_dm/amdgpu_dm.c
@@ -11821,8 +11821,16 @@ static int amdgpu_dm_atomic_check(struct drm_device 
*dev,
 
                /* Overlay cusor not subject to native cursor restrictions */
                dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
-               if (dm_new_crtc_state->cursor_mode == DM_CURSOR_OVERLAY_MODE)
+               if (dm_new_crtc_state->cursor_mode == DM_CURSOR_OVERLAY_MODE) {
+                       if (dc->current_state->stream_status->plane_count > 
MAX_SURFACES) {
+                               drm_dbg_driver(crtc->dev,
+                                      "Can't enable cursor plane with %d 
planes\n", MAX_SURFACES);
+                               ret = -EINVAL;
+                               goto fail;
+                       }
+
                        continue;
+               }
 
                /* Check if rotation or scaling is enabled on DCN401 */
                if ((drm_plane_mask(crtc->cursor) & new_crtc_state->plane_mask) 
&&
-- 
2.34.1