From patchwork Mon Feb 21 08:50:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 544657 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 85CCFC433EF for ; Mon, 21 Feb 2022 10:03:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352440AbiBUKEQ (ORCPT ); Mon, 21 Feb 2022 05:04:16 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:57298 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353502AbiBUJ53 (ORCPT ); Mon, 21 Feb 2022 04:57:29 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ACB748D; Mon, 21 Feb 2022 01:26:29 -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 4B49B60F8C; Mon, 21 Feb 2022 09:26:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 337A0C340E9; Mon, 21 Feb 2022 09:26:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1645435588; bh=42zi/zigIyIUQ1oqsPKN7CLx5IlCRHcYsWZ5A3UZKvg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xwxlS6l8PdgXLhcc7De8Y+jd5TpTkWUAz7INUaaKoR40P/6z2o/f3B0oDkCl54j7E iRmgcYO3EeEijY1UgnKWc2SySWAercv4qzGfb5lk47JvOwfGKfmqbip8QIFcDYJYL4 LDwXDCtBvGY652G2X5IObxm7TGajO7N2Mxt0Pil0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vladimir Zapolskiy , Robert Foss , Bjorn Andersson , Wolfram Sang Subject: [PATCH 5.16 184/227] i2c: qcom-cci: dont put a device tree node before i2c_add_adapter() Date: Mon, 21 Feb 2022 09:50:03 +0100 Message-Id: <20220221084940.937091035@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220221084934.836145070@linuxfoundation.org> References: <20220221084934.836145070@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vladimir Zapolskiy commit 02a4a69667a2ad32f3b52ca906f19628fbdd8a01 upstream. There is a minor chance for a race, if a pointer to an i2c-bus subnode is stored and then reused after releasing its reference, and it would be sufficient to get one more reference under a loop over children subnodes. Fixes: e517526195de ("i2c: Add Qualcomm CCI I2C driver") Signed-off-by: Vladimir Zapolskiy Reviewed-by: Robert Foss Reviewed-by: Bjorn Andersson Signed-off-by: Wolfram Sang Signed-off-by: Greg Kroah-Hartman --- drivers/i2c/busses/i2c-qcom-cci.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) --- a/drivers/i2c/busses/i2c-qcom-cci.c +++ b/drivers/i2c/busses/i2c-qcom-cci.c @@ -558,7 +558,7 @@ static int cci_probe(struct platform_dev cci->master[idx].adap.quirks = &cci->data->quirks; cci->master[idx].adap.algo = &cci_algo; cci->master[idx].adap.dev.parent = dev; - cci->master[idx].adap.dev.of_node = child; + cci->master[idx].adap.dev.of_node = of_node_get(child); cci->master[idx].master = idx; cci->master[idx].cci = cci; @@ -643,8 +643,10 @@ static int cci_probe(struct platform_dev continue; ret = i2c_add_adapter(&cci->master[i].adap); - if (ret < 0) + if (ret < 0) { + of_node_put(cci->master[i].adap.dev.of_node); goto error_i2c; + } } pm_runtime_set_autosuspend_delay(dev, MSEC_PER_SEC); @@ -656,8 +658,10 @@ static int cci_probe(struct platform_dev error_i2c: for (--i ; i >= 0; i--) { - if (cci->master[i].cci) + if (cci->master[i].cci) { i2c_del_adapter(&cci->master[i].adap); + of_node_put(cci->master[i].adap.dev.of_node); + } } error: disable_irq(cci->irq); @@ -673,8 +677,10 @@ static int cci_remove(struct platform_de int i; for (i = 0; i < cci->data->num_masters; i++) { - if (cci->master[i].cci) + if (cci->master[i].cci) { i2c_del_adapter(&cci->master[i].adap); + of_node_put(cci->master[i].adap.dev.of_node); + } cci_halt(cci, i); }