From patchwork Wed Feb 1 10:15:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 13124080 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 2E52BC678DB for ; Wed, 1 Feb 2023 10:16:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232138AbjBAKQi (ORCPT ); Wed, 1 Feb 2023 05:16:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51956 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232019AbjBAKQf (ORCPT ); Wed, 1 Feb 2023 05:16:35 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8FF524ED3E; Wed, 1 Feb 2023 02:16:34 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 02D0661757; Wed, 1 Feb 2023 10:16:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 235EDC4361B; Wed, 1 Feb 2023 10:16:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675246593; bh=0nF8bFxY3P5D9tTctpmyCeHRuEBYqHVlVkGhiXKBwvI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sz/RSIN67O56ujGi0CSF/0DVIJH32aKT1O15exs+nQ7Qbiz3JZaX8YQnhqQOhcVYF IExipRlxc1qw0prEIMH9jsgFFHERR0sGSJ/DKvik0ImXY+wpwX7uoUTUKbGSsU73YT VmDA17WCjEzSZ7JUu8WsIxEubtswYy/r5+pDsbncIfSCheRmzfbtlm2nQz1/XVOiIP Ep4+nEojXdkXUNdPmdULXeyPfiJ0EYWHvbQiN2PLftsmWMX8HmezLS+JfbLeEI5OjQ tU8X3ffKs8YfJAaz0uCXpc5t7NgbHZj9zOBCS+g+zU00yngr5ek6MDRNxTUeQRdrPP UPLkdGa4aY6Aw== Received: from johan by xi.lan with local (Exim 4.94.2) (envelope-from ) id 1pNAAg-00044K-Am; Wed, 01 Feb 2023 11:16:54 +0100 From: Johan Hovold To: Georgi Djakov Cc: Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , Andy Gross , Bjorn Andersson , Konrad Dybcio , Sylwester Nawrocki , =?utf-8?b?QXJ0dXIgxZp3aWdvxYQ=?= , Krzysztof Kozlowski , Alim Akhtar , Thierry Reding , Jonathan Hunter , linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold , stable@vger.kernel.org Subject: [PATCH 15/23] interconnect: exynos: fix registration race Date: Wed, 1 Feb 2023 11:15:51 +0100 Message-Id: <20230201101559.15529-16-johan+linaro@kernel.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230201101559.15529-1-johan+linaro@kernel.org> References: <20230201101559.15529-1-johan+linaro@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org The current interconnect provider registration interface is inherently racy as nodes are not added until the after adding the provider. This can specifically cause racing DT lookups to trigger a NULL-pointer deference when either a NULL pointer or not fully initialised node is returned from exynos_generic_icc_xlate(). Switch to using the new API where the provider is not registered until after it has been fully initialised. Fixes: 2f95b9d5cf0b ("interconnect: Add generic interconnect driver for Exynos SoCs") Cc: stable@vger.kernel.org # 5.11 Cc: Sylwester Nawrocki Signed-off-by: Johan Hovold Reviewed-by: Krzysztof Kozlowski --- drivers/interconnect/samsung/exynos.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/drivers/interconnect/samsung/exynos.c b/drivers/interconnect/samsung/exynos.c index e70665899482..72e42603823b 100644 --- a/drivers/interconnect/samsung/exynos.c +++ b/drivers/interconnect/samsung/exynos.c @@ -98,12 +98,13 @@ static int exynos_generic_icc_remove(struct platform_device *pdev) struct exynos_icc_priv *priv = platform_get_drvdata(pdev); struct icc_node *parent_node, *node = priv->node; + icc_provider_deregister(&priv->provider); + parent_node = exynos_icc_get_parent(priv->dev->parent->of_node); if (parent_node && !IS_ERR(parent_node)) icc_link_destroy(node, parent_node); icc_nodes_remove(&priv->provider); - icc_provider_del(&priv->provider); return 0; } @@ -132,15 +133,11 @@ static int exynos_generic_icc_probe(struct platform_device *pdev) provider->inter_set = true; provider->data = priv; - ret = icc_provider_add(provider); - if (ret < 0) - return ret; + icc_provider_init(provider); icc_node = icc_node_create(pdev->id); - if (IS_ERR(icc_node)) { - ret = PTR_ERR(icc_node); - goto err_prov_del; - } + if (IS_ERR(icc_node)) + return PTR_ERR(icc_node); priv->node = icc_node; icc_node->name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%pOFn", @@ -171,14 +168,17 @@ static int exynos_generic_icc_probe(struct platform_device *pdev) goto err_pmqos_del; } + ret = icc_provider_register(provider); + if (ret < 0) + goto err_pmqos_del; + return 0; err_pmqos_del: dev_pm_qos_remove_request(&priv->qos_req); err_node_del: icc_nodes_remove(provider); -err_prov_del: - icc_provider_del(provider); + return ret; }