From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932763AbcBPOyB (ORCPT ); Tue, 16 Feb 2016 09:54:01 -0500 Received: from mout.kundenserver.de ([217.72.192.75]:62629 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932273AbcBPOx7 (ORCPT ); Tue, 16 Feb 2016 09:53:59 -0500 From: Arnd Bergmann To: Mark Brown Cc: linux-arm-kernel@lists.infradead.org, Arnd Bergmann , Sangbeom Kim , Krzysztof Kozlowski , Liam Girdwood , linux-kernel@vger.kernel.org, linux-samsung-soc@vger.kernel.org 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= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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") --- 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; -- 2.7.0