From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 15D58C4332F for ; Sun, 18 Dec 2022 16:48:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232814AbiLRQsi (ORCPT ); Sun, 18 Dec 2022 11:48:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43996 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232805AbiLRQrG (ORCPT ); Sun, 18 Dec 2022 11:47:06 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3DF2A10FFD; Sun, 18 Dec 2022 08:17:23 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id EB821B80BE6; Sun, 18 Dec 2022 16:17:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE358C433F0; Sun, 18 Dec 2022 16:17:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1671380240; bh=FX7HYEbBIhWrHLNd17fteXtIabssxjGxuMAlpWlubRM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EDihH7QAiCq7UtFfQPGuF9M4kJcyC4KmNi4FwbIBO+Fx+h0pjaBPE+FlBkj1r4CBj BNO63Ei7xcTMfat2wa3l50i4VHspDJmEDDJw2IO1XxjJ9DDS55A/S9o5Glkak0hoO0 Hd4NHVUN5xTuw0f7E+/o/6rCcpCOROO1qaDdBfU2CMlZ/7iU8FMkUCH8MY5oDePgzW dwE5RcxA5wHq+C8qBeSbQVZPqAmRs/IvxPTomLxwwvBkUWidR3FrL9Ft8Ck9M4anh+ RRxy45Q/3NVBYIWT10dQXOTTsvCJGPq4aEZKDTtTHipJS4vLa1OFjks6Qv5qZmKWyp BBE0e/oW5SJVg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , Rob Clark , Sean Paul , Abhinav Kumar , linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, Dmitry Baryshkov , Daniel Vetter , Sasha Levin , airlied@gmail.com, daniel@ffwll.ch, swboyd@chromium.org, quic_khsieh@quicinc.com, johan+linaro@kernel.org, quic_sbillaka@quicinc.com, andersson@kernel.org, dri-devel@lists.freedesktop.org Subject: [PATCH AUTOSEL 5.10 19/39] drm/msm: Use drm_mode_copy() Date: Sun, 18 Dec 2022 11:15:39 -0500 Message-Id: <20221218161559.932604-19-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221218161559.932604-1-sashal@kernel.org> References: <20221218161559.932604-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ville Syrjälä [ Upstream commit b2a1c5ca50db22b3677676dd5bad5f6092429acf ] struct drm_display_mode embeds a list head, so overwriting the full struct with another one will corrupt the list (if the destination mode is on a list). Use drm_mode_copy() instead which explicitly preserves the list head of the destination mode. Even if we know the destination mode is not on any list using drm_mode_copy() seems decent as it sets a good example. Bad examples of not using it might eventually get copied into code where preserving the list head actually matters. Obviously one case not covered here is when the mode itself is embedded in a larger structure and the whole structure is copied. But if we are careful when copying into modes embedded in structures I think we can be a little more reassured that bogus list heads haven't been propagated in. @is_mode_copy@ @@ drm_mode_copy(...) { ... } @depends on !is_mode_copy@ struct drm_display_mode *mode; expression E, S; @@ ( - *mode = E + drm_mode_copy(mode, &E) | - memcpy(mode, E, S) + drm_mode_copy(mode, E) ) @depends on !is_mode_copy@ struct drm_display_mode mode; expression E; @@ ( - mode = E + drm_mode_copy(&mode, &E) | - memcpy(&mode, E, S) + drm_mode_copy(&mode, E) ) @@ struct drm_display_mode *mode; @@ - &*mode + mode Cc: Rob Clark Cc: Sean Paul Cc: Abhinav Kumar Cc: linux-arm-msm@vger.kernel.org Cc: freedreno@lists.freedesktop.org Reviewed-by: Dmitry Baryshkov Reviewed-by: Abhinav Kumar Reviewed-by: Daniel Vetter Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20221107192545.9896-5-ville.syrjala@linux.intel.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/msm/dp/dp_display.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c index 5a152d505dfb..1c3dcbc6cce8 100644 --- a/drivers/gpu/drm/msm/dp/dp_display.c +++ b/drivers/gpu/drm/msm/dp/dp_display.c @@ -848,7 +848,7 @@ static int dp_display_set_mode(struct msm_dp *dp_display, dp = container_of(dp_display, struct dp_display_private, dp_display); - dp->panel->dp_mode.drm_mode = mode->drm_mode; + drm_mode_copy(&dp->panel->dp_mode.drm_mode, &mode->drm_mode); dp->panel->dp_mode.bpp = mode->bpp; dp->panel->dp_mode.capabilities = mode->capabilities; dp_panel_init_panel_info(dp->panel); -- 2.35.1