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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 A51E3CA9EAF for ; Thu, 24 Oct 2019 16:41:21 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6E13E21929 for ; Thu, 24 Oct 2019 16:41:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="tyHDCLvs"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="DQl9V900" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6E13E21929 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=p1Y3grck6brgIuxqCvaSnCD7Yws+FQaJCCLUNqBIfv4=; b=tyHDCLvswzLP2WIeudm+9oeoI0 pBXHBNH6frsC1V9k/+6NGdExFsD3g61aBwgLn/3ZG8o2jdRhYeEJbxI7K/eG9twrr1CqW74Sw625x YMg4BTwWM3+bseRP21cJvxCgCoZPHqIWTcHWNpuyFcG4Pz0HQldH0D0Ugl/koHhOCZOB5hhD7yDSv 6+OpOVPQAwAF/28PlxBlxaFnHt3xOlFjp2hKrKVHEtXDJj3vJaWD+PFXB+ditjsizyg7Q+9QIrzvF 9sEXTeiFRkdnuDoheLx25My4vMkC8NeUJP9zeEvmudTxq1kWyyzv5hMDSenprx9NCa1o6jpBgFR6J 0EkgHWPQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iNgAo-0000TQ-RR; Thu, 24 Oct 2019 16:41:18 +0000 Received: from mail-wm1-x342.google.com ([2a00:1450:4864:20::342]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iNg8N-0005Pg-1z for linux-arm-kernel@lists.infradead.org; Thu, 24 Oct 2019 16:38:48 +0000 Received: by mail-wm1-x342.google.com with SMTP id c22so3259700wmd.1 for ; Thu, 24 Oct 2019 09:38:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=+Uje5yZA2ldJsbsoiBPp+JyZjTmn5fr8PAwcjGY2GnI=; b=DQl9V900fqGUpTL6GCaKfkeZ3gpfIHFqAKSX3ufvAjrIcUCC99G8QrABRgrFAHr84f zXLGkBQbvxYo558DCuJqQRDDXaj2qphtEatUBS+Lk2L/kgUEZOlNLKkQr/2VGOUirh4E 6jKdZxmOXPYIkjq+XUBdV+4Kw/ot1PyjPtVGHPHjzWvr5e5pNz9JmDdPSIPFVB09IPWO J99BmaTltlCpMUovCATgjqDRfUheM9tsvnCGce4Ysz+isq5zOjxTekh7k4kElKxW1h0I wSMBV1bRCLq9eaApiDlolzZZeA1p6It53pyezLs2vAm0LSkxnBL7yVJGV/ov+1Xf6Njw Chtw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=+Uje5yZA2ldJsbsoiBPp+JyZjTmn5fr8PAwcjGY2GnI=; b=Zi38Y8Jq9AQAHR5uRYnJL3O882CIr93UX+FlXlaLFDsqCxnWnf3JatgtuuNT3aX6Yz mUK8cd1EQgsqO5u4MaFfgB7x7TnkNyb4dfzrlmBkBynfxcC/k85Esezzi+YOj3SjKurN trObCr2o7lhHwp5MBOmaKNx2jwzaDCFRAhCuVEsZgfgYsw+RGpI/5sJa093trjadX+Gc +KDQQdJfDGnt54z9zFKudAQzWSjm/57JA77TME8zchXFqVGMPTptgTbIC43u/cofC+3E tFIeUZ6mPeU8XUVve3L8elxQtmuu7IDoXtc9Zw+PeWJoIsD29GQbKsQG3VmmMeHbWZE5 4TZQ== X-Gm-Message-State: APjAAAUd+cP2vQN4FkDT5Q+1GaKm7vFpyi2aPvRyN/uahNj8r8QuTR+e dd6ROJYcvqR0eRUICIGLAVEKsA== X-Google-Smtp-Source: APXvYqxlMNsjCTwkEt0d7L6AsHU/jq7MCFgUCZONkNBta21bcHrPhdZtg5MDI/XxzWmIHo3m+xvqdw== X-Received: by 2002:a05:600c:143:: with SMTP id w3mr786098wmm.132.1571935124805; Thu, 24 Oct 2019 09:38:44 -0700 (PDT) Received: from localhost.localdomain ([95.149.164.99]) by smtp.gmail.com with ESMTPSA id 6sm3446175wmd.36.2019.10.24.09.38.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 24 Oct 2019 09:38:44 -0700 (PDT) From: Lee Jones To: daniel.thompson@linaro.org, arnd@arndb.de, broonie@kernel.org, linus.walleij@linaro.org Subject: [PATCH v3 08/10] mfd: mfd-core: Protect against NULL call-back function pointer Date: Thu, 24 Oct 2019 17:38:30 +0100 Message-Id: <20191024163832.31326-9-lee.jones@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191024163832.31326-1-lee.jones@linaro.org> References: <20191024163832.31326-1-lee.jones@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191024_093847_156343_0DF98573 X-CRM114-Status: GOOD ( 13.99 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Lee Jones , baohua@kernel.org, stephan@gerhold.net, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org If a child device calls mfd_cell_{en,dis}able() without an appropriate call-back being set, we are likely to encounter a panic. Avoid this by adding suitable checking. Signed-off-by: Lee Jones Reviewed-by: Daniel Thompson --- drivers/mfd/mfd-core.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c index 8126665bb2d8..e38e411ca775 100644 --- a/drivers/mfd/mfd-core.c +++ b/drivers/mfd/mfd-core.c @@ -28,6 +28,11 @@ int mfd_cell_enable(struct platform_device *pdev) const struct mfd_cell *cell = mfd_get_cell(pdev); int err = 0; + if (!cell->enable) { + dev_dbg(&pdev->dev, "No .enable() call-back registered\n"); + return 0; + } + /* only call enable hook if the cell wasn't previously enabled */ if (atomic_inc_return(cell->usage_count) == 1) err = cell->enable(pdev); @@ -45,6 +50,11 @@ int mfd_cell_disable(struct platform_device *pdev) const struct mfd_cell *cell = mfd_get_cell(pdev); int err = 0; + if (!cell->disable) { + dev_dbg(&pdev->dev, "No .disable() call-back registered\n"); + return 0; + } + /* only disable if no other clients are using it */ if (atomic_dec_return(cell->usage_count) == 0) err = cell->disable(pdev); -- 2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel