drm: Use drm_mode_init() for on-stack modes

Initialize on-stack modes with drm_mode_init() to guarantee
no stack garbage in the list head, or that we aren't copying
over another mode's list head.

Based on the following cocci script, with manual fixups:
@decl@
identifier M;
expression E;
@@
- struct drm_display_mode M = E;
+ struct drm_display_mode M;

@@
identifier decl.M;
expression decl.E;
statement S, S1;
@@
struct drm_display_mode M;
... when != S
+ drm_mode_init(&M, &E);
+
S1

@@
expression decl.E;
@@
- &*E
+ E

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220218100403.7028-22-ville.syrjala@linux.intel.com
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>

diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index bff917531f3322371a659ef2e975a8ff7598fa46..a34aa009725f99244dd96e5cb229138ff7d9c2bc 100644 (file)
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -297,8 +297,8 @@ bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
                return false;
        }
 
-       saved_mode = crtc->mode;
-       saved_hwmode = crtc->hwmode;
+       drm_mode_init(&saved_mode, &crtc->mode);
+       drm_mode_init(&saved_hwmode, &crtc->hwmode);
        saved_x = crtc->x;
        saved_y = crtc->y;
 
@@ -411,8 +411,8 @@ done:
        drm_mode_destroy(dev, adjusted_mode);
        if (!ret) {
                crtc->enabled = saved_enabled;
-               crtc->mode = saved_mode;
-               crtc->hwmode = saved_hwmode;
+               drm_mode_copy(&crtc->mode, &saved_mode);
+               drm_mode_copy(&crtc->hwmode, &saved_hwmode);
                crtc->x = saved_x;
                crtc->y = saved_y;
        }

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 04e818ecd66253a1170d28d1c98a1987fb9f3f51..dbca588474c308a0e5c4ec7b85de5cd6637b51a4 100644 (file)
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -3551,9 +3551,11 @@ static u8 drm_match_cea_mode_clock_tolerance(const struct drm_display_mode *to_m
                match_flags |= DRM_MODE_MATCH_ASPECT_RATIO;
 
        for (vic = 1; vic < cea_num_vics(); vic = cea_next_vic(vic)) {
-               struct drm_display_mode cea_mode = *cea_mode_for_vic(vic);
+               struct drm_display_mode cea_mode;
                unsigned int clock1, clock2;
 
+               drm_mode_init(&cea_mode, cea_mode_for_vic(vic));
+
                /* Check both 60Hz and 59.94Hz */
                clock1 = cea_mode.clock;
                clock2 = cea_mode_alternate_clock(&cea_mode);
@@ -3590,9 +3592,11 @@ u8 drm_match_cea_mode(const struct drm_display_mode *to_match)
                match_flags |= DRM_MODE_MATCH_ASPECT_RATIO;
 
        for (vic = 1; vic < cea_num_vics(); vic = cea_next_vic(vic)) {
-               struct drm_display_mode cea_mode = *cea_mode_for_vic(vic);
+               struct drm_display_mode cea_mode;
                unsigned int clock1, clock2;
 
+               drm_mode_init(&cea_mode, cea_mode_for_vic(vic));
+
                /* Check both 60Hz and 59.94Hz */
                clock1 = cea_mode.clock;
                clock2 = cea_mode_alternate_clock(&cea_mode);

diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index 6e7e10f16ec036f9d6c99fce25571ae89a99a06d..e699950cc34d76152192654e24dc6c12c6af570e 100644 (file)
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -837,7 +837,9 @@ EXPORT_SYMBOL(drm_mode_vrefresh);
 void drm_mode_get_hv_timing(const struct drm_display_mode *mode,
                            int *hdisplay, int *vdisplay)
 {
-       struct drm_display_mode adjusted = *mode;
+       struct drm_display_mode adjusted;
+
+       drm_mode_init(&adjusted, mode);
 
        drm_mode_set_crtcinfo(&adjusted, CRTC_STEREO_DOUBLE_ONLY);
        *hdisplay = adjusted.crtc_hdisplay;