Blob Blame History Raw
From 57d40600efd749bd828259debe520f380297d81a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com>
Date: Wed, 9 Feb 2022 11:19:27 +0200
Subject: drm/atomic: Don't pollute crtc_state->mode_blob with error pointers
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Git-commit: 439cf34c8e0a8a33d8c15a31be1b7423426bc765
Patch-mainline: v5.17-rc5
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

Make sure we don't assign an error pointer to crtc_state->mode_blob
as that will break all kinds of places that assume either NULL or a
valid pointer (eg. drm_property_blob_put()).

Cc: stable@vger.kernel.org
Reported-by: fuyufan <fuyufan@huawei.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220209091928.14766-1-ville.syrjala@linux.intel.com
Acked-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/drm_atomic_uapi.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
index 9781722519c3..54d62fdb4ef9 100644
--- a/drivers/gpu/drm/drm_atomic_uapi.c
+++ b/drivers/gpu/drm/drm_atomic_uapi.c
@@ -76,15 +76,17 @@ int drm_atomic_set_mode_for_crtc(struct drm_crtc_state *state,
 	state->mode_blob = NULL;
 
 	if (mode) {
+		struct drm_property_blob *blob;
+
 		drm_mode_convert_to_umode(&umode, mode);
-		state->mode_blob =
-			drm_property_create_blob(state->crtc->dev,
-						 sizeof(umode),
-						 &umode);
-		if (IS_ERR(state->mode_blob))
-			return PTR_ERR(state->mode_blob);
+		blob = drm_property_create_blob(crtc->dev,
+						sizeof(umode), &umode);
+		if (IS_ERR(blob))
+			return PTR_ERR(blob);
 
 		drm_mode_copy(&state->mode, mode);
+
+		state->mode_blob = blob;
 		state->enable = true;
 		drm_dbg_atomic(crtc->dev,
 			       "Set [MODE:%s] for [CRTC:%d:%s] state %p\n",
-- 
2.38.1