From patchwork Tue Nov 27 17:05:04 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicholas Mc Guire X-Patchwork-Id: 10701083 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CBF4214BD for ; Tue, 27 Nov 2018 17:10:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B0A5E2C54D for ; Tue, 27 Nov 2018 17:10:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A45E82C589; Tue, 27 Nov 2018 17:10:54 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI,SUBJ_OBFU_PUNCT_FEW autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E2E472C54B for ; Tue, 27 Nov 2018 17:10:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726492AbeK1EJ0 (ORCPT ); Tue, 27 Nov 2018 23:09:26 -0500 Received: from www.osadl.org ([62.245.132.105]:48621 "EHLO www.osadl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726338AbeK1EJ0 (ORCPT ); Tue, 27 Nov 2018 23:09:26 -0500 Received: from debian01.hofrr.at (178.115.242.59.static.drei.at [178.115.242.59]) by www.osadl.org (8.13.8/8.13.8/OSADL-2007092901) with ESMTP id wARH81Zj008298; Tue, 27 Nov 2018 18:08:01 +0100 From: Nicholas Mc Guire To: Lars-Peter Clausen Cc: Michael Hennerich , Jonathan Cameron , Hartmut Knaack , Peter Meerwald-Stadler , Greg Kroah-Hartman , Dan Carpenter , Joe Perches , linux-iio@vger.kernel.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, Nicholas Mc Guire Subject: [PATCH V2] staging: iio: adc: ad7280a: check for devm_kasprint() failure Date: Tue, 27 Nov 2018 18:05:04 +0100 Message-Id: <1543338304-892-1-git-send-email-hofrat@osadl.org> X-Mailer: git-send-email 2.1.4 Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP devm_kasprintf() may return NULL on failure of internal allocation thus the assignments to attr.name are not safe if not checked. On error ad7280_attr_init() returns a negative return so -ENOMEM should be OK here (passed on as return value of the probe function). To make the error case more readable a temporary iio_attr is introduced and the code refactored. Signed-off-by: Nicholas Mc Guire Fixes: 2051f25d2a26 ("iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System2") --- V2: use a tmp pointer to iio_attr to make the error check more readable as proposed by Dan Carpenter Problem located with an experimental coccinelle script Patch was compile tested with: x86_64_defconfig + STAGING=y SPI=y, IIO=y, AD7280=m Patch is against 4.20-rc4 (localversion-next is next-20181127) drivers/staging/iio/adc/ad7280a.c | 43 +++++++++++++++++++-------------------- 1 file changed, 21 insertions(+), 22 deletions(-) diff --git a/drivers/staging/iio/adc/ad7280a.c b/drivers/staging/iio/adc/ad7280a.c index 0bb9ab1..7a0ba26 100644 --- a/drivers/staging/iio/adc/ad7280a.c +++ b/drivers/staging/iio/adc/ad7280a.c @@ -561,6 +561,7 @@ static int ad7280_attr_init(struct ad7280_state *st) { int dev, ch, cnt; unsigned int index; + struct iio_dev_attr *iio_attr; st->iio_attr = devm_kcalloc(&st->spi->dev, 2, sizeof(*st->iio_attr) * (st->slave_num + 1) * AD7280A_CELLS_PER_DEV, @@ -571,37 +572,35 @@ static int ad7280_attr_init(struct ad7280_state *st) for (dev = 0, cnt = 0; dev <= st->slave_num; dev++) for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_CELL_VOLTAGE_6; ch++, cnt++) { + iio_attr = &st->iio_attr[cnt]; index = dev * AD7280A_CELLS_PER_DEV + ch; - st->iio_attr[cnt].address = - ad7280a_devaddr(dev) << 8 | ch; - st->iio_attr[cnt].dev_attr.attr.mode = - 0644; - st->iio_attr[cnt].dev_attr.show = - ad7280_show_balance_sw; - st->iio_attr[cnt].dev_attr.store = - ad7280_store_balance_sw; - st->iio_attr[cnt].dev_attr.attr.name = + iio_attr->address = ad7280a_devaddr(dev) << 8 | ch; + iio_attr->dev_attr.attr.mode = 0644; + iio_attr->dev_attr.show = ad7280_show_balance_sw; + iio_attr->dev_attr.store = ad7280_store_balance_sw; + iio_attr->dev_attr.attr.name = devm_kasprintf(&st->spi->dev, GFP_KERNEL, "in%d-in%d_balance_switch_en", index, index + 1); - ad7280_attributes[cnt] = - &st->iio_attr[cnt].dev_attr.attr; + if (!iio_attr->dev_attr.attr.name) + return -ENOMEM; + + ad7280_attributes[cnt] = &iio_attr->dev_attr.attr; cnt++; - st->iio_attr[cnt].address = - ad7280a_devaddr(dev) << 8 | + iio_attr = &st->iio_attr[cnt]; + iio_attr->address = ad7280a_devaddr(dev) << 8 | (AD7280A_CB1_TIMER + ch); - st->iio_attr[cnt].dev_attr.attr.mode = - 0644; - st->iio_attr[cnt].dev_attr.show = - ad7280_show_balance_timer; - st->iio_attr[cnt].dev_attr.store = - ad7280_store_balance_timer; - st->iio_attr[cnt].dev_attr.attr.name = + iio_attr->dev_attr.attr.mode = 0644; + iio_attr->dev_attr.show = ad7280_show_balance_timer; + iio_attr->dev_attr.store = ad7280_store_balance_timer; + iio_attr->dev_attr.attr.name = devm_kasprintf(&st->spi->dev, GFP_KERNEL, "in%d-in%d_balance_timer", index, index + 1); - ad7280_attributes[cnt] = - &st->iio_attr[cnt].dev_attr.attr; + if (!iio_attr->dev_attr.attr.name) + return -ENOMEM; + + ad7280_attributes[cnt] = &iio_attr->dev_attr.attr; } ad7280_attributes[cnt] = NULL;