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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 559EFC43381 for ; Thu, 14 Mar 2019 14:06:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2513621852 for ; Thu, 14 Mar 2019 14:06:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=rasmusvillemoes.dk header.i=@rasmusvillemoes.dk header.b="iiyYDh0h" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727720AbfCNOGq (ORCPT ); Thu, 14 Mar 2019 10:06:46 -0400 Received: from mail-lf1-f65.google.com ([209.85.167.65]:37791 "EHLO mail-lf1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727595AbfCNOGa (ORCPT ); Thu, 14 Mar 2019 10:06:30 -0400 Received: by mail-lf1-f65.google.com with SMTP id u2so4302103lfd.4 for ; Thu, 14 Mar 2019 07:06:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rasmusvillemoes.dk; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=p8EpCtqjAm4J2CBGC1CDK0h+QRPUremQspzB4HLzQkM=; b=iiyYDh0hQqtDSOIY3ADO4E2t/q8s7H2qCJ/oyrbHGCDuy6vRE8qrSHTXgjOmLEegOP IAiloUMw7Ke5+3IjG3KwtFyvr34bq9MQT9Q/g4cdppRoZxBzhnXEl25Rtr0mZ3+ZJX1N DDzkFRpA3uftSDnDot9ocPU/iJoyMj7MVlcWs= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=p8EpCtqjAm4J2CBGC1CDK0h+QRPUremQspzB4HLzQkM=; b=iN9QhKugSF5pgsoPnTrDnskJUORtIHQAYVEhRMhAWKfOumD0CT02tkAhKuITINYY3m bG0ExsmY5R8kM/xJHFWMDIKeKSpOyntsUWmY+6aeimtJ/2IS0bYjUE/Q1zeB+kqXWZIV qYJRnFeSKvsPGOaxYxTIFMbBzjeoOWKQnsT6vzRXjChWjsrDhf3lwnrPnpBCJ6PdUQp8 Q6sAOMysAGzyTSndBW+fFRyYN/8KncVh28TLuAkKYyI1N4kgG9x4410ycoO3c3hV91bN q440qMBkBfD7IEOjYEo6UnfwKyuVVCnD4amsB8fULWYMxTB802OJErqe+PIExlakGGYo Y4/A== X-Gm-Message-State: APjAAAXa7Gz973RjRY0feB1C7yb+3cmmrU35lFtI2uImRYa9HHO+L1Ew ID4eBRwNTKWqBBEDuWvMVbxNdkk9nODtttNE X-Google-Smtp-Source: APXvYqzpk2z3DfJL4S6UzjKZnRyCDk3gmSZ35+QMup0ZVo7OrsOatZUkLGELgXwGaNdDICa1qFhHwA== X-Received: by 2002:ac2:4310:: with SMTP id l16mr25782184lfh.58.1552572388394; Thu, 14 Mar 2019 07:06:28 -0700 (PDT) Received: from prevas-ravi.prevas.se ([81.216.59.226]) by smtp.gmail.com with ESMTPSA id t14sm2733709lfe.51.2019.03.14.07.06.27 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 14 Mar 2019 07:06:28 -0700 (PDT) From: Rasmus Villemoes To: Pavel Machek , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , Jacek Anaszewski Cc: LKML , Rasmus Villemoes , linux-leds@vger.kernel.org Subject: [PATCH v2 4/6] leds: netdev trigger: move name length checking to netdev_trig_set_device Date: Thu, 14 Mar 2019 15:06:17 +0100 Message-Id: <20190314140619.3309-5-linux@rasmusvillemoes.dk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190314140619.3309-1-linux@rasmusvillemoes.dk> References: <20190313202615.22883-1-linux@rasmusvillemoes.dk> <20190314140619.3309-1-linux@rasmusvillemoes.dk> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It's better to check that size is sane in the function that does the memcpy'ing and 0-termination to the IFNAMSIZ-sized buffer instead of relying on callers getting it right. Not rejecting size upfront does mean we would do the cancel_delayed_work_sync(), but that gets fixed up by the set_baseline_state() call. Signed-off-by: Rasmus Villemoes --- drivers/leds/trigger/ledtrig-netdev.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/leds/trigger/ledtrig-netdev.c b/drivers/leds/trigger/ledtrig-netdev.c index c35439291424..e4a76ce4e4c7 100644 --- a/drivers/leds/trigger/ledtrig-netdev.c +++ b/drivers/leds/trigger/ledtrig-netdev.c @@ -104,9 +104,12 @@ static ssize_t device_name_show(struct device *dev, return len; } -static void netdev_trig_set_device(struct led_netdev_data *trigger_data, - const char *buf, size_t size) +static ssize_t netdev_trig_set_device(struct led_netdev_data *trigger_data, + const char *buf, size_t size) { + if (size >= IFNAMSIZ) + return -EINVAL; + if (trigger_data->net_dev) { dev_put(trigger_data->net_dev); trigger_data->net_dev = NULL; @@ -125,6 +128,7 @@ static void netdev_trig_set_device(struct led_netdev_data *trigger_data, set_bit(NETDEV_LED_MODE_LINKUP, &trigger_data->mode); trigger_data->last_activity = 0; + return 0; } static ssize_t device_name_store(struct device *dev, @@ -133,23 +137,22 @@ static ssize_t device_name_store(struct device *dev, { struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev); size_t orig_size = size; + ssize_t ret; /* Ignore trailing newline */ if (size > 0 && buf[size - 1] == '\n') size--; - if (size >= IFNAMSIZ) - return -EINVAL; cancel_delayed_work_sync(&trigger_data->work); spin_lock_bh(&trigger_data->lock); - netdev_trig_set_device(trigger_data, buf, size); + ret = netdev_trig_set_device(trigger_data, buf, size); set_baseline_state(trigger_data); spin_unlock_bh(&trigger_data->lock); - return orig_size; + return ret ? ret : orig_size; } static DEVICE_ATTR_RW(device_name); -- 2.20.1