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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6B12C433FE for ; Mon, 7 Nov 2022 21:41:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233557AbiKGVk7 (ORCPT ); Mon, 7 Nov 2022 16:40:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232308AbiKGVk6 (ORCPT ); Mon, 7 Nov 2022 16:40:58 -0500 Received: from mail-pf1-x42a.google.com (mail-pf1-x42a.google.com [IPv6:2607:f8b0:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8A48827FC5; Mon, 7 Nov 2022 13:40:57 -0800 (PST) Received: by mail-pf1-x42a.google.com with SMTP id i3so11915467pfc.11; Mon, 07 Nov 2022 13:40:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=4MIh6FUPd6bRzAAr4QRjkFihYjlOaa459CYPKztD6ZQ=; b=YGh02CAOhKVH0McFv4KzSvxTahloGGkcfV1/qliu/hfVciOW4jaFYya7tGMyFbLW2W wPUajOOKNfpyEZYJUHD87HLUwEcozLEkRsXYZg0056iAd0VsKBcSwMMdFU7VIdTTmM5+ i4zImocMVX97kEP98dz25qemc09kX97cXCVQLk3ueCvEp+RoPvJZ7SkBKubaKlOV4lrL dOuDPg/T/HNnD1mNZFtnJac/m8JkKhWL2gZCPRjt81M8F7jnJ3fLm11XgdMHRn0pq2hY QxQ5mkJctyh4P/AHlgEMUBRh4TdYq74JG+civx9iE2+lBFdAsTk4gfkVYiq2HMedp+4K MgWw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=4MIh6FUPd6bRzAAr4QRjkFihYjlOaa459CYPKztD6ZQ=; b=gc4TacA+cUJD3ml5afx67NHRZeX+7Z45vjmQA+o43yPW1oyV+2mtMq1egx6BIyYdWG /4x6PiWy4+r2Hcr5kYKlPgiYfXpUZ19H4h6MROl755ikvFVrxfbtWCydjVUQJwmlI/ap F3lNTg1AZlKqEIxLkC9xVbgXwqA0CngQw8arlUysIsdDW11gYc8y69pU+aDuyO+Jebn2 4QUOc/wQhNQx4zHQbbon/XICP1an3UOHTLn6339KJpARivpSdpUfGg8WPR8XQOPQq2rQ WQS06m53/LBiko+UdG0a2F0s1yAMASDWkMQTmv8R21Z6rAifTd6xxg34T7gETTnBxFWE X1tQ== X-Gm-Message-State: ACrzQf2gn53YUHlZy55tGIuN/AOv826hloliOwlOatOZemFiUHzNh0yR WBzPsxV5s9u5oPo0wl7sfSg= X-Google-Smtp-Source: AMsMyM4/jWq5qj2Rf6zWdlQ64H64Row+8w7UrlIqDgvF9mPredfh+BQEfyAK03/hmu0+havnYHED5g== X-Received: by 2002:a63:da4f:0:b0:43f:6af:74ed with SMTP id l15-20020a63da4f000000b0043f06af74edmr45958206pgj.290.1667857256868; Mon, 07 Nov 2022 13:40:56 -0800 (PST) Received: from google.com ([2620:15c:9d:2:fb10:b5b0:232e:4afb]) by smtp.gmail.com with ESMTPSA id q10-20020a170902bd8a00b00186bc66d2cbsm5417969pls.73.2022.11.07.13.40.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Nov 2022 13:40:56 -0800 (PST) Date: Mon, 7 Nov 2022 13:40:53 -0800 From: Dmitry Torokhov To: Andy Shevchenko Cc: Bartosz Golaszewski , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Linus Walleij Subject: Re: [PATCH v1 2/2] gpiolib: of: Integrate of_gpiochip_init_valid_mask() into gpiochip_init_valid_mask() Message-ID: References: <20221107161027.43384-1-andriy.shevchenko@linux.intel.com> <20221107161027.43384-2-andriy.shevchenko@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 07, 2022 at 11:09:19PM +0200, Andy Shevchenko wrote: > On Mon, Nov 07, 2022 at 10:20:37AM -0800, Dmitry Torokhov wrote: > > On Mon, Nov 07, 2022 at 06:10:27PM +0200, Andy Shevchenko wrote: > > > +static unsigned int gpiochip_count_reserved_ranges(struct gpio_chip *gc) > > > +{ > > > + int size; > > > + > > > + size = fwnode_property_count_u32(gc->fwnode, "gpio-reserved-ranges"); > > > > I wonder if a comment why we need even size would not be helpful. > > Was it in the original code? > Anyway, if Bart thinks so as well, I may add it in v2. > > > > + if (size > 0 && size % 2 == 0) > > > + return size; > > > + > > > + return 0; > > > +} > > > + > > > static int gpiochip_alloc_valid_mask(struct gpio_chip *gc) > > > { > > > - if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask)) > > > + if (!(gpiochip_count_reserved_ranges(gc) || gc->init_valid_mask)) > > > return 0; > > > > > > gc->valid_mask = gpiochip_allocate_mask(gc); > > > @@ -457,8 +468,47 @@ static int gpiochip_alloc_valid_mask(struct gpio_chip *gc) > > > return 0; > > > } > > > > > > +static int gpiochip_apply_reserved_ranges(struct gpio_chip *gc, unsigned int sz) > > > +{ > > > + u32 *ranges; > > > + int ret; > > > + > > > + ranges = kmalloc_array(sz, sizeof(*ranges), GFP_KERNEL); > > > + if (!ranges) > > > + return -ENOMEM; > > > + > > > + ret = fwnode_property_read_u32_array(gc->fwnode, "gpio-reserved-ranges", ranges, sz); > > > + if (ret) { > > > + kfree(ranges); > > > + return ret; > > > + } > > > + > > > + while (sz) { > > > + u32 count = ranges[--sz]; > > > + u32 start = ranges[--sz]; > > > > I know we checked sz validity, but I wonder if re-checking it in this > > function would not insulate us from errors creeping in after some other > > code refactoring. > > I'm not sure I understand what you meant. The fwnode_property_read_u32_array() > will fail if the given sz is too big for the real data, so while (sz) would > never even go on the invalid data. I am more worried about sz being odd and the loop ending up trying to dereference ranges[-1]. Thanks. -- Dmitry