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 24BBDC07545 for ; Wed, 25 Oct 2023 02:37:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232073AbjJYChk (ORCPT ); Tue, 24 Oct 2023 22:37:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51798 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232062AbjJYChi (ORCPT ); Tue, 24 Oct 2023 22:37:38 -0400 Received: from omta040.useast.a.cloudfilter.net (omta040.useast.a.cloudfilter.net [44.202.169.39]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9309A10D9 for ; Tue, 24 Oct 2023 19:37:35 -0700 (PDT) Received: from eig-obgw-6009a.ext.cloudfilter.net ([10.0.30.184]) by cmsmtp with ESMTPS id vLNhqpZkd6nOZvTm2qLpgV; Wed, 25 Oct 2023 02:37:34 +0000 Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with ESMTPS id vTm1qtE9COk5SvTm1q0r5e; Wed, 25 Oct 2023 02:37:33 +0000 X-Authority-Analysis: v=2.4 cv=E+DeGIRl c=1 sm=1 tr=0 ts=65387f6d a=1YbLdUo/zbTtOZ3uB5T3HA==:117 a=WzbPXH4gqzPVN0x6HrNMNA==:17 a=OWjo9vPv0XrRhIrVQ50Ab3nP57M=:19 a=dLZJa+xiwSxG16/P+YVxDGlgEgI=:19 a=_mNlVl-r0hj7kTaC:21 a=IkcTkHD0fZMA:10 a=bhdUkHdE2iEA:10 a=wYkD_t78qR0A:10 a=yiRjFQIvNRT05BO5IWcA:9 a=QEXdDO2ut3YA:10 a=N_l3Vs37sht3-TxgB6J7:22 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=embeddedor.com; s=default; h=Content-Transfer-Encoding:Content-Type: In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=IahuLxENwBvcQu5NawHPQqBuCWpwToxFKhWLnhbPsjA=; b=A6miGOebEelAgGO/y8Xg8CQaJ2 encD8KXpUYQA7Y57ewp1KWNFtAjLh0IdF7vZcMJdKh0a50bWUD68yixEX90aMwNzvTsEmGz3GoxEh AIQcmyyGSlVF/ChA64778Ek8Oht/x9PZG/AMRI4kubCRbkcfQPCunXdX/qM6NeUaqcn5FnyOsiy42 e3ZVgbvPm5QZ9KGnMogaJ125PG3bV3rZSPAF5VbXNGPSX5VayntbfDeCN7dUHAqbwm94mt9MismLX 8MV0Yp01UBJoG34XnWNMIXZrJH2WiJicdU33zSLBTITiJQuEG+fPE6GOzWyOTTbBqN/JZkJAvXSTK EVAt/XJA==; Received: from 187-162-21-192.static.axtel.net ([187.162.21.192]:56754 helo=[192.168.15.10]) by gator4166.hostgator.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.96.2) (envelope-from ) id 1qvTm0-003HJe-2k; Tue, 24 Oct 2023 21:37:32 -0500 Message-ID: <8219c79e-0359-4136-afa4-fba76fde191a@embeddedor.com> Date: Tue, 24 Oct 2023 20:37:31 -0600 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC - is this a bug?] wifi: ath10k: Asking for some light on this, please :) Content-Language: en-US To: Johannes Berg , Kalle Valo , Jeff Johnson Cc: ath10k@lists.infradead.org, linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" , linux-hardening@vger.kernel.org References: <626ae2e7-66f8-423b-b17f-e75c1a6d29b3@embeddedor.com> <26b15f4702cef17fe70b496a62f03735874bd16a.camel@sipsolutions.net> <07e9bb04-f9fc-46d5-bfb9-a00a63a707c0@embeddedor.com> From: "Gustavo A. R. Silva" In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 187.162.21.192 X-Source-L: No X-Exim-ID: 1qvTm0-003HJe-2k X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: 187-162-21-192.static.axtel.net ([192.168.15.10]) [187.162.21.192]:56754 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 3 X-Org: HG=hgshared;ORG=hostgator; X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes X-CMAE-Envelope: MS4xfES+hWMGisRisjUK6MhRPwQzEbQ/VkW2wcMqTeqRa0FP4it/pF9e9OKOizrvu1YySjrSwFq6mdmY7uyI1wrUetej3xj16aKlB99zzlrnlzrYEmoobhrD Ef/lDkeKnL4gu2DlOglB4TgMzuuJcrq9Yagu2RmFllgkXMM7eGJV7WByH+TMfnJBGbpYrxfbSjlLZsgraNlnW9Wy17iJG9zdU1OsK0ovtJG5LngWMjIKbkyV Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/24/23 14:49, Johannes Berg wrote: > On Tue, 2023-10-24 at 14:41 -0600, Gustavo A. R. Silva wrote: >> >> It seems we run into the same issue in the function below, even in the >> case this `memset()` is unnecessary (which it seems it's not): >> >> 8920 memset(skb->data, 0, sizeof(*cmd)); >> >> Notice that if `cap->peer_chan_len == 0` or `cap->peer_chan_len == 1`, >> in the original code, we have `len == sizeof(*cmd) == 128`: > > Right. > >> - /* tdls peer update cmd has place holder for one channel*/ >> - chan_len = cap->peer_chan_len ? (cap->peer_chan_len - 1) : 0; >> - >> - len = sizeof(*cmd) + chan_len * sizeof(*chan); >> + len = struct_size(cmd, peer_capab.peer_chan_list, cap->peer_chan_len); >> >> skb = ath10k_wmi_alloc_skb(ar, len); >> if (!skb) >> >> which makes `round_len == roundup(len, 4) == struct_size(cmd,...,...) == 104` >> when `cap->peer_chan_len == 0` > > And yeah, that's really the issue, it only matters for ==0. For a moment > there I thought that doesn't even make sense, but it looks like it never > even becomes non-zero. > > No idea then, sorry. You'd hope firmware doesn't care about the actual > message size if the inner data says "0 entries", but who knows? And how > many firmware versions are there? :) > > So I guess you'd want to stay compatible, even if it means having a > > chan_len = min(cap->peer_chan_len, 1); > > for the struct_size()? Yeah, that's an alternative. I'll wait for the maintainers to chime in and see if they have a different opinion. Thanks -- Gustavo