From patchwork Sat May 21 03:35:35 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yongzhi Liu X-Patchwork-Id: 575277 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 E7293C433FE for ; Sat, 21 May 2022 03:36:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346958AbiEUDgI (ORCPT ); Fri, 20 May 2022 23:36:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33638 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354466AbiEUDgH (ORCPT ); Fri, 20 May 2022 23:36:07 -0400 Received: from zg8tmtyylji0my4xnjqumte4.icoremail.net (zg8tmtyylji0my4xnjqumte4.icoremail.net [162.243.164.118]) by lindbergh.monkeyblade.net (Postfix) with SMTP id E1C15220F8; Fri, 20 May 2022 20:36:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pku.edu.cn; s=dkim; h=Received:From:To:Cc:Subject:Date: Message-Id:In-Reply-To:References; bh=wzgzdu7AuK5zx/MuP4XOVfBFXx Nsi5pQH7m0wAb0gCo=; b=X5b2XxOOCRGY8Jb1B1DBIYP3XP74DSwIK3HUmUZpVV i8vYsFwdMSFLYYqkHEtFHtPVUwV3NYtljq2vyAROP2ptfYr4nqa9xA1ebV65nZ3a 6C74csk6aLBGRgwjFl3RduR2TK+JUQUURq6G7PsYK8LbC2NMjgoiFF6jqdnG8984 A= Received: from localhost (unknown [10.129.21.144]) by front02 (Coremail) with SMTP id 54FpogAHinYKXohiR2PABg--.12714S2; Sat, 21 May 2022 11:35:38 +0800 (CST) From: Yongzhi Liu To: agross@kernel.org, bjorn.andersson@linaro.org, jic23@kernel.org, lars@metafoo.de, svarbanov@mm-sol.com, iivanov@mm-sol.com, jonathan.cameron@huawei.com Cc: linux-arm-msm@vger.kernel.org, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, fuyq@stu.pku.edu.cn, Yongzhi Liu Subject: [PATCH v3] iio: vadc: Fix potential dereference of NULL pointer Date: Fri, 20 May 2022 20:35:35 -0700 Message-Id: <1653104135-36259-1-git-send-email-lyz_cs@pku.edu.cn> X-Mailer: git-send-email 2.7.4 In-Reply-To: <20220520181323.00002892@huawei.com> References: <20220520181323.00002892@huawei.com> X-CM-TRANSID: 54FpogAHinYKXohiR2PABg--.12714S2 X-Coremail-Antispam: 1UD129KBjvJXoW7urWfuFy5Kry8Jr1xXr4fXwb_yoW5Jr1Upa 98JayrGry7Ka1fJFyfAFWDJF1aqw42qayUCFWxGanIyr1ayrnYyr4ag3WFyrn5CFyxCw43 Ar4jvFnY9F4DKF7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9F1xkIjI8I6I8E6xAIw20EY4v20xvaj40_Wr0E3s1l1IIY67AE w4v_Jr0_Jr4l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2 IY67AKxVWDJVCq3wA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8Jr0_Cr1UM28EF7xvwVC2 z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AIxVAIcxkEcV Aq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r10 6r15McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64 vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E8cxan2IY04v7MxkIecxE wVCm-wCF04k20xvY0x0EwIxGrwCF04k20xvE74AGY7Cv6cx26w4UJr1UMxC20s026xCaFV Cjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWl x4CE17CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r 1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_ JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcS sGvfC2KfnxnUUI43ZEXa7VU1a9aPUUUUU== X-CM-SenderInfo: irzqijirqukmo6sn3hxhgxhubq/1tbiAwEMBlPy7vKeCwAIso Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org The return value of vadc_get_channel() needs to be checked to avoid use of NULL pointer. Fix this by adding the null pointer check on prop and dropping general error prints. Fixes: 0917de94c02f ("iio: vadc: Qualcomm SPMI PMIC voltage ADC driver") Signed-off-by: Yongzhi Liu --- drivers/iio/adc/qcom-spmi-vadc.c | 38 ++++++++++++++++++++++++++++---------- 1 file changed, 28 insertions(+), 10 deletions(-) diff --git a/drivers/iio/adc/qcom-spmi-vadc.c b/drivers/iio/adc/qcom-spmi-vadc.c index 34202ba..43a52b1 100644 --- a/drivers/iio/adc/qcom-spmi-vadc.c +++ b/drivers/iio/adc/qcom-spmi-vadc.c @@ -358,22 +358,33 @@ static int vadc_measure_ref_points(struct vadc_priv *vadc) vadc->graph[VADC_CALIB_ABSOLUTE].dx = VADC_ABSOLUTE_RANGE_UV; prop = vadc_get_channel(vadc, VADC_REF_1250MV); + if (!prop) { + dev_err(vadc->dev, "Please define 1.25V channel\n"); + ret = -ENODEV; + return ret; + } ret = vadc_do_conversion(vadc, prop, &read_1); if (ret) - goto err; + return ret; /* Try with buffered 625mV channel first */ prop = vadc_get_channel(vadc, VADC_SPARE1); - if (!prop) + if (!prop) { prop = vadc_get_channel(vadc, VADC_REF_625MV); + if (!prop) { + dev_err(vadc->dev, "Please define 0.625V channel\n"); + ret = -ENODEV; + return ret; + } + } ret = vadc_do_conversion(vadc, prop, &read_2); if (ret) - goto err; + return ret; if (read_1 == read_2) { ret = -EINVAL; - goto err; + return ret; } vadc->graph[VADC_CALIB_ABSOLUTE].dy = read_1 - read_2; @@ -381,25 +392,32 @@ static int vadc_measure_ref_points(struct vadc_priv *vadc) /* Ratiometric calibration */ prop = vadc_get_channel(vadc, VADC_VDD_VADC); + if (!prop) { + dev_err(vadc->dev, "Please define VDD channel\n"); + ret = -ENODEV; + return ret; + } ret = vadc_do_conversion(vadc, prop, &read_1); if (ret) - goto err; + return ret; prop = vadc_get_channel(vadc, VADC_GND_REF); + if (!prop) { + dev_err(vadc->dev, "Please define GND channel\n"); + ret = -ENODEV; + return ret; + } ret = vadc_do_conversion(vadc, prop, &read_2); if (ret) - goto err; + return ret; if (read_1 == read_2) { ret = -EINVAL; - goto err; + return ret; } vadc->graph[VADC_CALIB_RATIOMETRIC].dy = read_1 - read_2; vadc->graph[VADC_CALIB_RATIOMETRIC].gnd = read_2; -err: - if (ret) - dev_err(vadc->dev, "measure reference points failed\n"); return ret; }