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 7E24BC41535 for ; Tue, 10 May 2022 13:44:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244874AbiEJNrE (ORCPT ); Tue, 10 May 2022 09:47:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56472 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243929AbiEJNcW (ORCPT ); Tue, 10 May 2022 09:32:22 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DC4645FCA; Tue, 10 May 2022 06:23:51 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 667B2B81DA8; Tue, 10 May 2022 13:23:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CD271C385C6; Tue, 10 May 2022 13:23:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1652189029; bh=HoOfi01wBxkhtS/69h0Be3htZAnNoys6Mua3ZN7jUoY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GNjYzHZFjib28irKa5tMGE2YojhgFfMTwwZBiOZX7tDoO3BocNGRz83N58LJTl6jG bZzOCzrRo87JxzAV1fOkZ02/4nfULESKbMPNZWBC2JNoUvr8fiiIyHSZP8UY0ae5LX 8r9nZ1ZWIgFjbsK42hd1uNsiMLVOynY0ZZ8ImZVU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andrei Lalaev , Andy Shevchenko , Linus Walleij , Bartosz Golaszewski Subject: [PATCH 5.4 04/52] gpiolib: of: fix bounds check for gpio-reserved-ranges Date: Tue, 10 May 2022 15:07:33 +0200 Message-Id: <20220510130729.984881193@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220510130729.852544477@linuxfoundation.org> References: <20220510130729.852544477@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andrei Lalaev commit e75f88efac05bf4e107e4171d8db6d8c3937252d upstream. Gpiolib interprets the elements of "gpio-reserved-ranges" as "start,size" because it clears "size" bits starting from the "start" bit in the according bitmap. So it has to use "greater" instead of "greater or equal" when performs bounds check to make sure that GPIOs are in the available range. Previous implementation skipped ranges that include the last GPIO in the range. I wrote the mail to the maintainers (https://lore.kernel.org/linux-gpio/20220412115554.159435-1-andrei.lalaev@emlid.com/T/#u) of the questioned DTSes (because I couldn't understand how the maintainers interpreted this property), but I haven't received a response. Since the questioned DTSes use "gpio-reserved-ranges = <0 4>" (i.e., the beginning of the range), this patch doesn't affect these DTSes at all. TBH this patch doesn't break any existing DTSes because none of them reserve gpios at the end of range. Fixes: 726cb3ba4969 ("gpiolib: Support 'gpio-reserved-ranges' property") Signed-off-by: Andrei Lalaev Reviewed-by: Andy Shevchenko Reviewed-by: Linus Walleij Cc: stable@vger.kernel.org Signed-off-by: Bartosz Golaszewski Signed-off-by: Greg Kroah-Hartman --- drivers/gpio/gpiolib-of.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -783,7 +783,7 @@ static void of_gpiochip_init_valid_mask( i, &start); of_property_read_u32_index(np, "gpio-reserved-ranges", i + 1, &count); - if (start >= chip->ngpio || start + count >= chip->ngpio) + if (start >= chip->ngpio || start + count > chip->ngpio) continue; bitmap_clear(chip->valid_mask, start, count);