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=-16.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 24575C433DF for ; Thu, 16 Jul 2020 18:03:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EBF2720578 for ; Thu, 16 Jul 2020 18:03:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594922616; bh=5KwcsaBu7BUQxh20BOcLc3hsF8YKVmjgY6g59//hEzI=; h=Date:From:To:Cc:Subject:List-ID:From; b=1BBuCMtb4jDFpSbyRIq63P1/MSDunxHtakCzrkWq2yEqmbn5CtHBuxOqbe6BaK+o8 yqAZsKX/jX2Qlslj4bHgVjDHR45F8kYN5Rt6U7Ud6l4fimSKfMRuEv7OYrQqksjzY8 Hsbi/aD3TmIjCLahpo1F9N2ltPN145qv2n58m3L8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729066AbgGPSDe (ORCPT ); Thu, 16 Jul 2020 14:03:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:60304 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728257AbgGPSDe (ORCPT ); Thu, 16 Jul 2020 14:03:34 -0400 Received: from embeddedor (unknown [201.162.240.161]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 51F8420578; Thu, 16 Jul 2020 18:03:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594922613; bh=5KwcsaBu7BUQxh20BOcLc3hsF8YKVmjgY6g59//hEzI=; h=Date:From:To:Cc:Subject:From; b=SxptUY5oeRchbMENgLCF+DFzAIl11WhRny/okAoL8iAphdsnJTNiVyvFby67Mj6SO 2B2mem2bKBrHs+MYuuXTuZu2LhRrhAs8+Eae6agJ9lSTiJB7zzHjDa6k/5OsDuG18D Vhtm8A6y3TNGzAVcXfQbVGu4NxU72fAW7fvQWW9s= Date: Thu, 16 Jul 2020 13:08:58 -0500 From: "Gustavo A. R. Silva" To: Greg Kroah-Hartman , Jiri Slaby Cc: linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH][next] tty: Avoid the use of one-element arrays Message-ID: <20200716180858.GA30115@embeddedor> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org One-element arrays are being deprecated[1]. Replace the one-element arrays with simple value types 'char reserved_char' and 'compat_int_t reserved'[2], once it seems these are just placeholders for alignment. Also, while there, use the preferred form for passing a size of a struct. The alternative form where struct name is spelled out hurts readability and introduces an opportunity for a bug when the variable type is changed but the corresponding sizeof that is passed as argument is not. Lastly, fix the checkpatch.pl warnings below: ERROR: code indent should use tabs where possible + char reserved_char;$ WARNING: please, no spaces at the start of a line + char reserved_char;$ ERROR: code indent should use tabs where possible + compat_int_t reserved;$ WARNING: please, no spaces at the start of a line + compat_int_t reserved;$ [1] https://github.com/KSPP/linux/issues/79 [2] https://github.com/KSPP/linux/issues/86 Tested-by: kernel test robot Link: https://github.com/GustavoARSilva/linux-hardening/blob/master/cii/0-day/tty-20200716.md Signed-off-by: Gustavo A. R. Silva --- drivers/tty/tty_io.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index 5a6f36b391d9..505bcba5ee02 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -2683,7 +2683,7 @@ struct serial_struct32 { compat_int_t baud_base; unsigned short close_delay; char io_type; - char reserved_char[1]; + char reserved_char; compat_int_t hub6; unsigned short closing_wait; /* time to wait before closing */ unsigned short closing_wait2; /* no longer used... */ @@ -2691,7 +2691,7 @@ struct serial_struct32 { unsigned short iomem_reg_shift; unsigned int port_high; /* compat_ulong_t iomap_base FIXME */ - compat_int_t reserved[1]; + compat_int_t reserved; }; static int compat_tty_tiocsserial(struct tty_struct *tty, @@ -2705,7 +2705,7 @@ static int compat_tty_tiocsserial(struct tty_struct *tty, struct serial_struct v; int flags; - if (copy_from_user(&v32, ss, sizeof(struct serial_struct32))) + if (copy_from_user(&v32, ss, sizeof(*ss))) return -EFAULT; memcpy(&v, &v32, offsetof(struct serial_struct32, iomem_base)); @@ -2743,7 +2743,7 @@ static int compat_tty_tiocgserial(struct tty_struct *tty, 0xfffffff : ptr_to_compat(v.iomem_base); v32.iomem_reg_shift = v.iomem_reg_shift; v32.port_high = v.port_high; - if (copy_to_user(ss, &v32, sizeof(struct serial_struct32))) + if (copy_to_user(ss, &v32, sizeof(v32))) err = -EFAULT; } return err; -- 2.27.0