From patchwork Mon Feb 18 10:16:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Krzysztof Kozlowski X-Patchwork-Id: 10817691 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DD8B017FB for ; Mon, 18 Feb 2019 10:17:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CE7E72A378 for ; Mon, 18 Feb 2019 10:17:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C2B092A39B; Mon, 18 Feb 2019 10:17:12 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7F89F2A378 for ; Mon, 18 Feb 2019 10:17:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729987AbfBRKRG (ORCPT ); Mon, 18 Feb 2019 05:17:06 -0500 Received: from mail.kernel.org ([198.145.29.99]:32854 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729956AbfBRKRE (ORCPT ); Mon, 18 Feb 2019 05:17:04 -0500 Received: from PC-kkoz.proceq.com (unknown [213.160.61.66]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A7A3421848; Mon, 18 Feb 2019 10:17:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550485024; bh=gNf/5Uk/N77EbTBib61uKhWZvxLozaD5/JezwNFwHzw=; h=From:To:Subject:Date:In-Reply-To:References:From; b=vAsukM95NUgr4qNKVk5IRNPMc2r5dElrspwsCt8JStKBTfiYNP5AERGeI9p5RtiUF LYAcQEOMzfWkf4CX30NXtxkz314WbP7KT8GfziSgzDJICueG5P0YRpxkOBrsYvI0VG RUX8kQuIyNfWmaFiSxDaCUEs2v8BaYM1apg82I6I= From: Krzysztof Kozlowski To: Russell King , Mark Brown , linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org, Greg Kroah-Hartman , "Rafael J. Wysocki" , Sylwester Nawrocki , Tomasz Figa , Chanwoo Choi , Michael Turquette , Stephen Boyd , Kukjin Kim , Krzysztof Kozlowski , Andy Gross , David Brown , Srinivas Kandagatla , linux-samsung-soc@vger.kernel.org, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, alsa-devel@alsa-project.org Subject: [RFC 4/4] slimbus: ngd: Fix kfree() of const memory on setting driver_override Date: Mon, 18 Feb 2019 11:16:00 +0100 Message-Id: <1550484960-2392-5-git-send-email-krzk@kernel.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1550484960-2392-1-git-send-email-krzk@kernel.org> References: <1550484960-2392-1-git-send-email-krzk@kernel.org> Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Platform driver driver_override field should not be initialized from const memory because the core later kfree() it. If driver_override is manually set later through sysfs, kfree() of old value leads to: $ echo "new_value" > /sys/bus/platform/drivers/.../driver_override kernel BUG at ../mm/slub.c:3960! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM ... (kfree) from [] (platform_set_driver_override+0x84/0xac) (platform_set_driver_override) from [] (driver_override_store+0x20/0x34) (driver_override_store) from [] (kernfs_fop_write+0x100/0x1dc) (kernfs_fop_write) from [] (__vfs_write+0x2c/0x17c) (__vfs_write) from [] (vfs_write+0xa4/0x188) (vfs_write) from [] (ksys_write+0x4c/0xac) (ksys_write) from [] (ret_fast_syscall+0x0/0x28) Signed-off-by: Krzysztof Kozlowski --- drivers/slimbus/qcom-ngd-ctrl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/slimbus/qcom-ngd-ctrl.c b/drivers/slimbus/qcom-ngd-ctrl.c index 71f094c9ec68..fc46bf6ec903 100644 --- a/drivers/slimbus/qcom-ngd-ctrl.c +++ b/drivers/slimbus/qcom-ngd-ctrl.c @@ -1344,7 +1344,7 @@ static int of_qcom_slim_ngd_register(struct device *parent, ngd->pdev = platform_device_alloc(QCOM_SLIM_NGD_DRV_NAME, id); ngd->id = id; ngd->pdev->dev.parent = parent; - ngd->pdev->driver_override = QCOM_SLIM_NGD_DRV_NAME; + platform_set_driver_override(ngd->pdev, QCOM_SLIM_NGD_DRV_NAME); ngd->pdev->dev.of_node = node; ctrl->ngd = ngd; platform_set_drvdata(ngd->pdev, ctrl);