From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELvhoPDm1tzbGck+K+RgiA3F8JQ8JD9ygQFnekndrK6nhfBIQl5CGrMUEAEafhsDVypePrC/ ARC-Seal: i=1; a=rsa-sha256; t=1520949020; cv=none; d=google.com; s=arc-20160816; b=rDC5zAJPiSDFsEAdjsn4ZkPKcssRLvcS+vS1/m8Isf7bpyXZ4JMqfyfhIgmaJhP+St 2AYlCSazf4DOw3A4Pcwsyk8fT7ifeCLoSeN7cpJdN8p8EG2Kzl4nKUEmLWRQ4Abegwu/ Hbnzg1OFr02fYq928eszL3FFDzfwIj1t5zrlb/zNLZVimoq9Wlj9WGQqyfsForw9af0s AFZFmHTeW4+JSQ/hbMdMegFvK9qPDMvKnM03NizmQ9GaXRViy3PA6BWLsYYpFBlbRmcJ KhxM4GuAzRFC4PBZ0fwmSyyqZ/BPtM5LkR5Qt/LB0NA88aioFTSKEUJmI8dWrqTQiDqr /0zg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:content-language:in-reply-to:mime-version :user-agent:date:message-id:from:references:cc:to:subject :delivered-to:delivered-to:list-id:list-subscribe:list-unsubscribe :list-help:list-post:precedence:mailing-list :arc-authentication-results; bh=Bv/113MeNLFNpaFVC4KkCndAsSuDbTyF7Vq83n6Bod8=; b=dOT076KDiV8QMSUR+bfms+mBVmtQrxZRK8wnUIyIk9KybiE6bH+cB9tBSyuRQfFx4e cT/5zVPDnMiYkeKccjjJwSj3acEUD7Fg54HCzhvz+Kqe1AV4g+g1/lp/x1MzmnE7mw/c K6XJKvEt945fX/pAqLxYbYKDlf100/NAx6ZZmA3Lce8txbnYoUDnQHz3S7DOgmPgEy+X M63TQrVnEVwSD+VR2rKo4pmNLKU3oSzBqEnW3nV4EWUjZx9a8Gxp1uTq5a+8iVxwY/cU +DmFiDvBXpA+ePVnhbuoHTMSx5AOr3DVxtU3Q1Vwa6uJlpcZYoIdnZHvh/87PidLcx8+ IPGA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of kernel-hardening-return-12505-gregkh=linuxfoundation.org@lists.openwall.com designates 195.42.179.200 as permitted sender) smtp.mailfrom=kernel-hardening-return-12505-gregkh=linuxfoundation.org@lists.openwall.com Authentication-Results: mx.google.com; spf=pass (google.com: domain of kernel-hardening-return-12505-gregkh=linuxfoundation.org@lists.openwall.com designates 195.42.179.200 as permitted sender) smtp.mailfrom=kernel-hardening-return-12505-gregkh=linuxfoundation.org@lists.openwall.com Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm List-Post: List-Help: List-Unsubscribe: List-Subscribe: Subject: Re: [PATCH 4/4] gpio: Remove VLA from stmpe driver To: Laura Abbott , Linus Walleij , Kees Cook , Patrice Chotard Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com References: <20180310001021.6437-1-labbott@redhat.com> <20180310001021.6437-5-labbott@redhat.com> From: Phil Reid Message-ID: <9175611d-049d-ec28-0716-e45fccfd579f@electromag.com.au> Date: Tue, 13 Mar 2018 17:13:06 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180310001021.6437-5-labbott@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-AU Content-Transfer-Encoding: 7bit X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1594507326034109383?= X-GMAIL-MSGID: =?utf-8?q?1594830640132788495?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On 10/03/2018 08:10, Laura Abbott wrote: > The new challenge is to remove VLAs from the kernel > (see https://lkml.org/lkml/2018/3/7/621) > > This patch replaces a VLA with an appropriate call to kmalloc_array. > > Signed-off-by: Laura Abbott > --- > drivers/gpio/gpio-stmpe.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpio/gpio-stmpe.c b/drivers/gpio/gpio-stmpe.c > index f8d7d1cd8488..b7854850bcdb 100644 > --- a/drivers/gpio/gpio-stmpe.c > +++ b/drivers/gpio/gpio-stmpe.c > @@ -369,10 +369,14 @@ static irqreturn_t stmpe_gpio_irq(int irq, void *dev) > struct stmpe *stmpe = stmpe_gpio->stmpe; > u8 statmsbreg; > int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8); > - u8 status[num_banks]; > + u8 *status; > int ret; > int i; > > + status = kmalloc_array(num_banks, sizeof(*status), GFP_ATOMIC); > + if (!status) > + return IRQ_NONE; > + > /* > * the stmpe_block_read() call below, imposes to set statmsbreg > * with the register located at the lowest address. As STMPE1600 > @@ -424,6 +428,7 @@ static irqreturn_t stmpe_gpio_irq(int irq, void *dev) > } > } > > + kfree(status); > return IRQ_HANDLED; > } > > Doing this in an irq handler seems wrong. Perhaps better if a buffer is pre-allocated in stmpe_gpio -- Regards Phil Reid