From patchwork Tue Feb 16 14:53:11 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 8327461 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 559689F38B for ; Tue, 16 Feb 2016 14:55:27 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7BD8B2025B for ; Tue, 16 Feb 2016 14:55:26 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9B8A620259 for ; Tue, 16 Feb 2016 14:55:24 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1aVh0n-0006VV-8m; Tue, 16 Feb 2016 14:53:57 +0000 Received: from mout.kundenserver.de ([217.72.192.75]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1aVh0j-0006G7-K4 for linux-arm-kernel@lists.infradead.org; Tue, 16 Feb 2016 14:53:54 +0000 Received: from wuerfel.lan. ([78.42.132.4]) by mrelayeu.kundenserver.de (mreue102) with ESMTPA (Nemesis) id 0M8QnS-1ZivqA16FW-00vxBh; Tue, 16 Feb 2016 15:53:24 +0100 From: Arnd Bergmann To: Mark Brown Subject: [PATCH] regulator: s5m8767: fix get_register() error handling Date: Tue, 16 Feb 2016 15:53:11 +0100 Message-Id: <1455634402-1997203-1-git-send-email-arnd@arndb.de> X-Mailer: git-send-email 2.7.0 X-Provags-ID: V03:K0:ZCtT/liupFpiJcVlnyYWRG3sUHEUSq1/xdTiiYXMCZ6MC/0o0xj SafBvJoaSSRT9tHHmJuL82nd+dSzslge0q+jras9E44ZJ7madYsBb/n2QHWoghjmfZdQ3Ev ZLES83o+2dWKil+ikmyG+okx4rJEqv2UukJDOx8mhN+0dcaAywMbcHB8ZmUBnwZAk5DJo14 /0/dDT5PArpKR/lbyh2+g== X-UI-Out-Filterresults: notjunk:1; V01:K0:AIX7nsAN+ck=:DIp036UwPTlv1lj/pZbq3M RVHLr54BLNqHdmyjf1WUL/SAM4soERhB1XTC/zB+vNn26CZo8fpeyfKpVM0P9MLpJ/kibf6rq cpc/O76Wh+KaUs0kaPgpjjZsZ801FBbkOgyE4HKNGnd3XK29epFbNueA9MrO4N1dMPJ2ct+7D vaXAC0/8M7ncYanARDnTWpWvsDvdpNDoE8aPUEQL6lUpXBpFzyXx2EYBQyI8eH4s/n/ZXh7AD lRSzkBZ7DnWRlFTDD38VQY6cm2vuURNR6rXDheHEI6EolFeQkWEehpwvvBJjPM+HOvKyTYnpA 848ICYgahDnYP+H0ZzCgvQIJ4+xbqy0U9jdd1Gx7u6S3ePcCyJV/Qxl/mSamG8f2r3X1OuwU+ 8ZcG66XjEha9bzTu/wUABlNTGOOQsttiKxR/tSFd6NIyJkaQy+zGs+6p5xe1fzDFG3fsgj3DS /kkMwJOXL+MzVB5RvSBctg2PZW7nWw6/xuxs0Fy3Ga5P/0gCVOG22cIHlrAruWqVuS0/0Ph3g mks+HovTJfQMdV3Ziq7eRP5T8s0FxoB9W4zpqO473uYIBKUrIDICyFNnWk7mi1MY+bd8JJDNi UPi8+GZI3jehdtTvEYIz1oQppaMzxS9X7skvj23sJsOQ8t2S+RfhjxhVS9YN2l1ZagXJv1NGG k8XQPOSc55pGq9d++opEuLLYhJ42Hv/mkEMz8R0+ZUJRghp+HW8DJDvmH0fjNrS6Td/4= X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160216_065354_034186_88071F70 X-CRM114-Status: GOOD ( 13.22 ) X-Spam-Score: -1.9 (-) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Krzysztof Kozlowski , linux-samsung-soc@vger.kernel.org, Arnd Bergmann , Sangbeom Kim , linux-kernel@vger.kernel.org, Liam Girdwood , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The s5m8767_pmic_probe() function calls s5m8767_get_register() to read data without checking the return code, which produces a compile-time warning when that data is accessed: drivers/regulator/s5m8767.c: In function 's5m8767_pmic_probe': drivers/regulator/s5m8767.c:924:7: error: 'enable_reg' may be used uninitialized in this function [-Werror=maybe-uninitialized] drivers/regulator/s5m8767.c:944:30: error: 'enable_val' may be used uninitialized in this function [-Werror=maybe-uninitialized] This changes the s5m8767_get_register() function to return a -EINVAL not just for an invalid register number but also for an invalid regulator number, as both would result in returning uninitialized data. The s5m8767_pmic_probe() function is then changed accordingly to fail on a read error, as all the other callers of s5m8767_get_register() already do. In practice this probably cannot happen, as we don't call s5m8767_get_register() with invalid arguments, but the gcc warning seems valid in principle, in terms writing safe error checking. Signed-off-by: Arnd Bergmann Fixes: 9c4c60554acf ("regulator: s5m8767: Convert to use regulator_[enable|disable|is_enabled]_regmap") Reviewed-by: Krzysztof Kozlowski --- drivers/regulator/s5m8767.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/regulator/s5m8767.c b/drivers/regulator/s5m8767.c index 58f5d3b8e981..27343e1c43ef 100644 --- a/drivers/regulator/s5m8767.c +++ b/drivers/regulator/s5m8767.c @@ -202,9 +202,10 @@ static int s5m8767_get_register(struct s5m8767_info *s5m8767, int reg_id, } } - if (i < s5m8767->num_regulators) - *enable_ctrl = - s5m8767_opmode_reg[reg_id][mode] << S5M8767_ENCTRL_SHIFT; + if (i >= s5m8767->num_regulators) + return -EINVAL; + + *enable_ctrl = s5m8767_opmode_reg[reg_id][mode] << S5M8767_ENCTRL_SHIFT; return 0; } @@ -937,8 +938,12 @@ static int s5m8767_pmic_probe(struct platform_device *pdev) else regulators[id].vsel_mask = 0xff; - s5m8767_get_register(s5m8767, id, &enable_reg, + ret = s5m8767_get_register(s5m8767, id, &enable_reg, &enable_val); + if (ret) { + dev_err(s5m8767->dev, "error reading registers\n"); + return ret; + } regulators[id].enable_reg = enable_reg; regulators[id].enable_mask = S5M8767_ENCTRL_MASK; regulators[id].enable_val = enable_val;