drm/amd/display: Fix UBSAN warning for not a valid value for type '_Bool'

[Why]
dc_cursor_position do not initialise position.translate_by_source when
crtc or plane->state->fb is NULL. UBSAN caught this error in
dce110_set_cursor_position, as the value was garbage.

[How]
Initialise dc_cursor_position structure elements to 0 in handle_cursor_update
before calling get_cursor_position.

Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1471
Reported-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Anson Jacob <Anson.Jacob@amd.com>
Reviewed-by: Aurabindo Jayamohanan Pillai <Aurabindo.Pillai@amd.com>
Acked-by: Solomon Chiu <solomon.chiu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 2cf745c6d93a28382949245b41c7c79cfe50a6d2..2c93ac2f77945cb26c2127e363b8514ff4f476b9 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -7521,10 +7521,6 @@ static int get_cursor_position(struct drm_plane *plane, struct drm_crtc *crtc,
        int x, y;
        int xorigin = 0, yorigin = 0;
 
-       position->enable = false;
-       position->x = 0;
-       position->y = 0;
-
        if (!crtc || !plane->state->fb)
                return 0;
 
@@ -7571,7 +7567,7 @@ static void handle_cursor_update(struct drm_plane *plane,
        struct dm_crtc_state *crtc_state = crtc ? to_dm_crtc_state(crtc->state) : NULL;
        struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
        uint64_t address = afb ? afb->address : 0;
-       struct dc_cursor_position position;
+       struct dc_cursor_position position = {0};
        struct dc_cursor_attributes attributes;
        int ret;