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=unavailable 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 F0DE7C432C0 for ; Wed, 27 Nov 2019 20:47:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C863C217C3 for ; Wed, 27 Nov 2019 20:47:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574887645; bh=tWAdVYLHMTE3vCjickhx0yIbPKCzlQ9aZb9fEW8zGJA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=MV7CdFosFCggjbrchlIcIvGxIg1SWKS/zysH2ctcw7v8Tsk1ganOvkKpIk98J3aO+ odb4FdJAAsiyWhqRsh5SZjiv9U1bdv0oh6VDZocfvw3Oyw2Zy+V/eDrMirXqUpM5Vq V2av2dYQUPXyGj/N4uidDKRSz+5zB1gG14ffREl8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729998AbfK0UrY (ORCPT ); Wed, 27 Nov 2019 15:47:24 -0500 Received: from mail.kernel.org ([198.145.29.99]:60068 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729991AbfK0UrV (ORCPT ); Wed, 27 Nov 2019 15:47:21 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 71FF921843; Wed, 27 Nov 2019 20:47:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574887639; bh=tWAdVYLHMTE3vCjickhx0yIbPKCzlQ9aZb9fEW8zGJA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Db+5jsQFDuy5flOkWZQXpy8I29rVZW27vFhHHrwZnqJFW2jAF3dtO7FJ95miSi6Ot O9awg67uWupBpPzgWsP12rlKeV5CWqGjueQuCfdbWFXUXx5FUtYY7837isSwYiFRU1 2fOfUbwiGex2np/Zds50+45DquzxAHLH3/wEBlm0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Julien Folly , Evgeniy Polyakov , Sasha Levin Subject: [PATCH 4.14 036/211] w1: IAD Register is yet readable trough iad sys file. Fix snprintf (%u for unsigned, count for max size). Date: Wed, 27 Nov 2019 21:29:29 +0100 Message-Id: <20191127203055.364271538@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191127203049.431810767@linuxfoundation.org> References: <20191127203049.431810767@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Julien Folly [ Upstream commit 6eaafbb6998e999467cf78a76e155ee00e372b14 ] IAD Register is yet readable trough the "iad" sys file. A write to the "iad" sys file enables or disables the current measurement, but it was not possible to get the measured value by reading it. Fix: %u in snprintf for unsigned values (vdd and vad) Fix: Avoid possibles overflows (Usage of the 'count' variables) Signed-off-by: Julien Folly Acked-by: Evgeniy Polyakov Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/w1/slaves/w1_ds2438.c | 66 +++++++++++++++++++++++++++-------- 1 file changed, 52 insertions(+), 14 deletions(-) diff --git a/drivers/w1/slaves/w1_ds2438.c b/drivers/w1/slaves/w1_ds2438.c index bf641a191d077..7c4e33dbee4d5 100644 --- a/drivers/w1/slaves/w1_ds2438.c +++ b/drivers/w1/slaves/w1_ds2438.c @@ -186,8 +186,8 @@ static int w1_ds2438_change_config_bit(struct w1_slave *sl, u8 mask, u8 value) return -1; } -static uint16_t w1_ds2438_get_voltage(struct w1_slave *sl, - int adc_input, uint16_t *voltage) +static int w1_ds2438_get_voltage(struct w1_slave *sl, + int adc_input, uint16_t *voltage) { unsigned int retries = W1_DS2438_RETRIES; u8 w1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/]; @@ -235,6 +235,25 @@ static uint16_t w1_ds2438_get_voltage(struct w1_slave *sl, return ret; } +static int w1_ds2438_get_current(struct w1_slave *sl, int16_t *voltage) +{ + u8 w1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/]; + int ret; + + mutex_lock(&sl->master->bus_mutex); + + if (w1_ds2438_get_page(sl, 0, w1_buf) == 0) { + /* The voltage measured across current sense resistor RSENS. */ + *voltage = (((int16_t) w1_buf[DS2438_CURRENT_MSB]) << 8) | ((int16_t) w1_buf[DS2438_CURRENT_LSB]); + ret = 0; + } else + ret = -1; + + mutex_unlock(&sl->master->bus_mutex); + + return ret; +} + static ssize_t iad_write(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count) @@ -257,6 +276,27 @@ static ssize_t iad_write(struct file *filp, struct kobject *kobj, return ret; } +static ssize_t iad_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, char *buf, + loff_t off, size_t count) +{ + struct w1_slave *sl = kobj_to_w1_slave(kobj); + int ret; + int16_t voltage; + + if (off != 0) + return 0; + if (!buf) + return -EINVAL; + + if (w1_ds2438_get_current(sl, &voltage) == 0) { + ret = snprintf(buf, count, "%i\n", voltage); + } else + ret = -EIO; + + return ret; +} + static ssize_t page0_read(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count) @@ -272,9 +312,13 @@ static ssize_t page0_read(struct file *filp, struct kobject *kobj, mutex_lock(&sl->master->bus_mutex); + /* Read no more than page0 size */ + if (count > DS2438_PAGE_SIZE) + count = DS2438_PAGE_SIZE; + if (w1_ds2438_get_page(sl, 0, w1_buf) == 0) { - memcpy(buf, &w1_buf, DS2438_PAGE_SIZE); - ret = DS2438_PAGE_SIZE; + memcpy(buf, &w1_buf, count); + ret = count; } else ret = -EIO; @@ -289,7 +333,6 @@ static ssize_t temperature_read(struct file *filp, struct kobject *kobj, { struct w1_slave *sl = kobj_to_w1_slave(kobj); int ret; - ssize_t c = PAGE_SIZE; int16_t temp; if (off != 0) @@ -298,8 +341,7 @@ static ssize_t temperature_read(struct file *filp, struct kobject *kobj, return -EINVAL; if (w1_ds2438_get_temperature(sl, &temp) == 0) { - c -= snprintf(buf + PAGE_SIZE - c, c, "%d\n", temp); - ret = PAGE_SIZE - c; + ret = snprintf(buf, count, "%i\n", temp); } else ret = -EIO; @@ -312,7 +354,6 @@ static ssize_t vad_read(struct file *filp, struct kobject *kobj, { struct w1_slave *sl = kobj_to_w1_slave(kobj); int ret; - ssize_t c = PAGE_SIZE; uint16_t voltage; if (off != 0) @@ -321,8 +362,7 @@ static ssize_t vad_read(struct file *filp, struct kobject *kobj, return -EINVAL; if (w1_ds2438_get_voltage(sl, DS2438_ADC_INPUT_VAD, &voltage) == 0) { - c -= snprintf(buf + PAGE_SIZE - c, c, "%d\n", voltage); - ret = PAGE_SIZE - c; + ret = snprintf(buf, count, "%u\n", voltage); } else ret = -EIO; @@ -335,7 +375,6 @@ static ssize_t vdd_read(struct file *filp, struct kobject *kobj, { struct w1_slave *sl = kobj_to_w1_slave(kobj); int ret; - ssize_t c = PAGE_SIZE; uint16_t voltage; if (off != 0) @@ -344,15 +383,14 @@ static ssize_t vdd_read(struct file *filp, struct kobject *kobj, return -EINVAL; if (w1_ds2438_get_voltage(sl, DS2438_ADC_INPUT_VDD, &voltage) == 0) { - c -= snprintf(buf + PAGE_SIZE - c, c, "%d\n", voltage); - ret = PAGE_SIZE - c; + ret = snprintf(buf, count, "%u\n", voltage); } else ret = -EIO; return ret; } -static BIN_ATTR(iad, S_IRUGO | S_IWUSR | S_IWGRP, NULL, iad_write, 1); +static BIN_ATTR(iad, S_IRUGO | S_IWUSR | S_IWGRP, iad_read, iad_write, 0); static BIN_ATTR_RO(page0, DS2438_PAGE_SIZE); static BIN_ATTR_RO(temperature, 0/* real length varies */); static BIN_ATTR_RO(vad, 0/* real length varies */); -- 2.20.1