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 X-Spam-Level: X-Spam-Status: No, score=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A0125C433ED for ; Mon, 5 Apr 2021 16:07:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6E3B0613B8 for ; Mon, 5 Apr 2021 16:07:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239568AbhDEQHr (ORCPT ); Mon, 5 Apr 2021 12:07:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:58836 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239080AbhDEQFm (ORCPT ); Mon, 5 Apr 2021 12:05:42 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 96208613C0; Mon, 5 Apr 2021 16:05:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1617638736; bh=NP6z82y8UYkzlwGvlhVl2v3BmtjsrN94IHTrZKg4lEo=; h=From:To:Cc:Subject:Date:From; b=ZROe7LlMT6MwG4TlmQ3u5PADCm06R8hE0h/sr5t47+A+VoLa7potm6dEn1DmFiBaK 7ER8hOdup7kX924bF3biHP+KLYZxNAgq8zD4/1fyliZhcwnnofodZZ/tSvYjINEC3f OooUGOsX/Teit31yixeEqkZROriMZUfTULH4QXCqWPuC6d2YGZcB87aiLbTjHCJtX4 eqtVCb0OBCmtg9ftXtCX/SuGWLdRGLUvAru2RoTcvmbLlq/nEi/KcBwQxu8rqmWE07 gEk0nOOkM33/WMC3BzK0t/9R4Lqoq2kGu0ibha6D4nX5sSK0P/bQbGcJFtrt5hZkAb Q0RQSy00hM4rQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Arnd Bergmann , Liu Ying , Philipp Zabel , Sasha Levin , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH AUTOSEL 4.9 1/2] drm/imx: imx-ldb: fix out of bounds array access warning Date: Mon, 5 Apr 2021 12:05:33 -0400 Message-Id: <20210405160534.269237-1-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnd Bergmann [ Upstream commit 33ce7f2f95cabb5834cf0906308a5cb6103976da ] When CONFIG_OF is disabled, building with 'make W=1' produces warnings about out of bounds array access: drivers/gpu/drm/imx/imx-ldb.c: In function 'imx_ldb_set_clock.constprop': drivers/gpu/drm/imx/imx-ldb.c:186:8: error: array subscript -22 is below array bounds of 'struct clk *[4]' [-Werror=array-bounds] Add an error check before the index is used, which helps with the warning, as well as any possible other error condition that may be triggered at runtime. The warning could be fixed by adding a Kconfig depedency on CONFIG_OF, but Liu Ying points out that the driver may hit the out-of-bounds problem at runtime anyway. Signed-off-by: Arnd Bergmann Reviewed-by: Liu Ying Signed-off-by: Philipp Zabel Signed-off-by: Sasha Levin --- drivers/gpu/drm/imx/imx-ldb.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/gpu/drm/imx/imx-ldb.c b/drivers/gpu/drm/imx/imx-ldb.c index 2df407b2b0da..3a9d06de81b4 100644 --- a/drivers/gpu/drm/imx/imx-ldb.c +++ b/drivers/gpu/drm/imx/imx-ldb.c @@ -212,6 +212,11 @@ static void imx_ldb_encoder_enable(struct drm_encoder *encoder) int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN; int mux = drm_of_encoder_active_port_id(imx_ldb_ch->child, encoder); + if (mux < 0 || mux >= ARRAY_SIZE(ldb->clk_sel)) { + dev_warn(ldb->dev, "%s: invalid mux %d\n", __func__, mux); + return; + } + drm_panel_prepare(imx_ldb_ch->panel); if (dual) { @@ -270,6 +275,11 @@ imx_ldb_encoder_atomic_mode_set(struct drm_encoder *encoder, int mux = drm_of_encoder_active_port_id(imx_ldb_ch->child, encoder); u32 bus_format = imx_ldb_ch->bus_format; + if (mux < 0 || mux >= ARRAY_SIZE(ldb->clk_sel)) { + dev_warn(ldb->dev, "%s: invalid mux %d\n", __func__, mux); + return; + } + if (mode->clock > 170000) { dev_warn(ldb->dev, "%s: mode exceeds 170 MHz pixel clock\n", __func__); -- 2.30.2