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 48C7417CA12; Mon, 10 Mar 2025 17:50:12 +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=1741629012; cv=none; b=UeeB/m9P/DyGAoeqNNbA/vnzgIivueFCH/+6W8cgicHfgXScvICd7Ut7Ini6OeA++edcTRdoYc2O2kt4nLFUW5GFn/dGqqx1QkDLatPa39vov1u10f4B934wJXDdCIENlX9MEUfF8zjqUFbReQHYgXBJn0jPGMgJge3SJCcHtgo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741629012; c=relaxed/simple; bh=AHB46nykNMEa4QLj3sFFmODH+RKaYOOk3EksdX6mCNI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ALmqPIuCpD2EilM/p8K6dOZbR8Uw0LVq4agiL/qi1ABV4Hf2ovlMqc7dHsDirm53hMgGy+/laSJYKFHxxk3MDs15YcHIXwtcPwawqeKUBPUJJ6o5UGfiN2nMQclNG01ehATPYAmsdoJYVDleza7oGfp6BJguz3rj5GF0idX97oA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=AV68LurD; 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="AV68LurD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C33F0C4CEE5; Mon, 10 Mar 2025 17:50:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1741629012; bh=AHB46nykNMEa4QLj3sFFmODH+RKaYOOk3EksdX6mCNI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AV68LurDO48STr/MrGCyQ1EcommWS7xy7ZeUh3jfHwAnKEt+ETrAqpFvNhs6g+1z1 Qu8zbb5m0ziiLRSkeD/qW/1V7OYSI2ayD4efjoAgaLZtHU5Sp2G2YpvV2UDq8irxfq OTECJMrBeq3q+GjqeWBvQoZGCEOVU6Tc4t9pCgOE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Joe Hattori , Krzysztof Kozlowski , Sasha Levin Subject: [PATCH 5.15 115/620] memory: tegra20-emc: fix an OF node reference bug in tegra_emc_find_node_by_ram_code() Date: Mon, 10 Mar 2025 17:59:21 +0100 Message-ID: <20250310170550.143662482@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250310170545.553361750@linuxfoundation.org> References: <20250310170545.553361750@linuxfoundation.org> User-Agent: quilt/0.68 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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Joe Hattori [ Upstream commit b9784e5cde1f9fb83661a70e580e381ae1264d12 ] As of_find_node_by_name() release the reference of the argument device node, tegra_emc_find_node_by_ram_code() releases some device nodes while still in use, resulting in possible UAFs. According to the bindings and the in-tree DTS files, the "emc-tables" node is always device's child node with the property "nvidia,use-ram-code", and the "lpddr2" node is a child of the "emc-tables" node. Thus utilize the for_each_child_of_node() macro and of_get_child_by_name() instead of of_find_node_by_name() to simplify the code. This bug was found by an experimental verification tool that I am developing. Fixes: 96e5da7c8424 ("memory: tegra: Introduce Tegra20 EMC driver") Signed-off-by: Joe Hattori Link: https://lore.kernel.org/r/20241217091434.1993597-1-joe@pf.is.s.u-tokyo.ac.jp Link: https://lore.kernel.org/r/20241218024415.2494267-3-joe@pf.is.s.u-tokyo.ac.jp [krzysztof: applied v1, adjust the commit msg to incorporate v2 parts] Signed-off-by: Krzysztof Kozlowski Signed-off-by: Sasha Levin --- drivers/memory/tegra/tegra20-emc.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/memory/tegra/tegra20-emc.c b/drivers/memory/tegra/tegra20-emc.c index 497b6edbf3ca1..2ac074b96f859 100644 --- a/drivers/memory/tegra/tegra20-emc.c +++ b/drivers/memory/tegra/tegra20-emc.c @@ -477,14 +477,15 @@ tegra_emc_find_node_by_ram_code(struct tegra_emc *emc) ram_code = tegra_read_ram_code(); - for (np = of_find_node_by_name(dev->of_node, "emc-tables"); np; - np = of_find_node_by_name(np, "emc-tables")) { + for_each_child_of_node(dev->of_node, np) { + if (!of_node_name_eq(np, "emc-tables")) + continue; err = of_property_read_u32(np, "nvidia,ram-code", &value); if (err || value != ram_code) { struct device_node *lpddr2_np; bool cfg_mismatches = false; - lpddr2_np = of_find_node_by_name(np, "lpddr2"); + lpddr2_np = of_get_child_by_name(np, "lpddr2"); if (lpddr2_np) { const struct lpddr2_info *info; @@ -521,7 +522,6 @@ tegra_emc_find_node_by_ram_code(struct tegra_emc *emc) } if (cfg_mismatches) { - of_node_put(np); continue; } } -- 2.39.5