From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BCB4B33DECE; Wed, 21 Jan 2026 18:26:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769020015; cv=none; b=DLyfiqD9odI+ULadNReIlhfwGGGju7WdYalweFl7a8aSY6EbK4srDZAYpqLl6tEh++3Y/8G4MY9qrqHqV1+jtMUq3bLS7J02PUKUcSGWDZSca848kLNGqeZvb49eeXpqZQt2DjwxXOrT5xFkJEDDNrfxX2DiAEbw+ga9lCxw4CU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769020015; c=relaxed/simple; bh=LeqHAOMU8SG2C1mTUCxCnFBnvNetOLVkYSeSXk5zSCM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=F/2w2CooibiEsKBHH51gRJeUVtjR3SQ+q1ixjSIloIucrbEbDdrTXJs5OOk7XhG7ARe6/DK7rBtkSDDDVToS2hvR25FRQeS0vXBUazWGBnudee6umTu+MTqQVsmGFBXJb3qJ8vzCPI8nNpP5DrvdyjCcVKW57BSUOCxhmXIT3v4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Us0cNAxr; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Us0cNAxr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A418FC4CEF1; Wed, 21 Jan 2026 18:26:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1769020015; bh=LeqHAOMU8SG2C1mTUCxCnFBnvNetOLVkYSeSXk5zSCM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Us0cNAxrrsShO7ZHGZIEelXNeqtufQ4QN3MvgOxIuYbTDrtZHjmRoZGtCRgYT3CL/ EeUAKUesais3kHlP0XHGRXBXRN5OlLofsIy51TLjsZHs9mjBI42BUjCDKhYrdtjBFl 7YNrV1Ks4GIo4p1dgO6TwP3/YuATS09xnT7znrpU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Shenghao Yang , Ruben Wauters Subject: [PATCH 6.18 009/198] drm/gud: fix NULL fb and crtc dereferences on USB disconnect Date: Wed, 21 Jan 2026 19:13:57 +0100 Message-ID: <20260121181418.881060368@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260121181418.537774329@linuxfoundation.org> References: <20260121181418.537774329@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Shenghao Yang commit dc2d5ddb193e363187bae2ad358245642d2721fb upstream. On disconnect drm_atomic_helper_disable_all() is called which sets both the fb and crtc for a plane to NULL before invoking a commit. This causes a kernel oops on every display disconnect. Add guards for those dereferences. Cc: # 6.18.x Fixes: 73cfd166e045 ("drm/gud: Replace simple display pipe with DRM atomic helpers") Signed-off-by: Shenghao Yang Reviewed-by: Ruben Wauters Signed-off-by: Ruben Wauters Link: https://patch.msgid.link/20251231055039.44266-1-me@shenghaoyang.info Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/gud/gud_pipe.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/gud/gud_pipe.c b/drivers/gpu/drm/gud/gud_pipe.c index 76d77a736d84..4b77be94348d 100644 --- a/drivers/gpu/drm/gud/gud_pipe.c +++ b/drivers/gpu/drm/gud/gud_pipe.c @@ -457,27 +457,20 @@ int gud_plane_atomic_check(struct drm_plane *plane, struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state, plane); struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state, plane); struct drm_crtc *crtc = new_plane_state->crtc; - struct drm_crtc_state *crtc_state; + struct drm_crtc_state *crtc_state = NULL; const struct drm_display_mode *mode; struct drm_framebuffer *old_fb = old_plane_state->fb; struct drm_connector_state *connector_state = NULL; struct drm_framebuffer *fb = new_plane_state->fb; - const struct drm_format_info *format = fb->format; + const struct drm_format_info *format; struct drm_connector *connector; unsigned int i, num_properties; struct gud_state_req *req; int idx, ret; size_t len; - if (drm_WARN_ON_ONCE(plane->dev, !fb)) - return -EINVAL; - - if (drm_WARN_ON_ONCE(plane->dev, !crtc)) - return -EINVAL; - - crtc_state = drm_atomic_get_new_crtc_state(state, crtc); - - mode = &crtc_state->mode; + if (crtc) + crtc_state = drm_atomic_get_new_crtc_state(state, crtc); ret = drm_atomic_helper_check_plane_state(new_plane_state, crtc_state, DRM_PLANE_NO_SCALING, @@ -492,6 +485,9 @@ int gud_plane_atomic_check(struct drm_plane *plane, if (old_plane_state->rotation != new_plane_state->rotation) crtc_state->mode_changed = true; + mode = &crtc_state->mode; + format = fb->format; + if (old_fb && old_fb->format != format) crtc_state->mode_changed = true; @@ -598,7 +594,7 @@ void gud_plane_atomic_update(struct drm_plane *plane, struct drm_atomic_helper_damage_iter iter; int ret, idx; - if (crtc->state->mode_changed || !crtc->state->enable) { + if (!crtc || crtc->state->mode_changed || !crtc->state->enable) { cancel_work_sync(&gdrm->work); mutex_lock(&gdrm->damage_lock); if (gdrm->fb) { -- 2.52.0