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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 989B5C43214 for ; Wed, 18 Aug 2021 07:09:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8443B60462 for ; Wed, 18 Aug 2021 07:09:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238908AbhHRHJp (ORCPT ); Wed, 18 Aug 2021 03:09:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58874 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238745AbhHRHJj (ORCPT ); Wed, 18 Aug 2021 03:09:39 -0400 Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AFD82C061764; Wed, 18 Aug 2021 00:09:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sipsolutions.net; s=mail; h=Content-Transfer-Encoding:MIME-Version: Content-Type:References:In-Reply-To:Date:Cc:To:From:Subject:Message-ID:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To: Resent-Cc:Resent-Message-ID; bh=ym1uD8O5zOub+cpikC9nk8w/uDg8kA95v0fuB8biuWo=; t=1629270544; x=1630480144; b=p1Ld4iQXUw+HDTOMXfbZh8MdkvWZs01KD6dhfc0MHu3ANOJ kjikpASrlMR5ErUwflDXgeN/ePfPdk6uHK5YkYndKFme44SGe7PFapUGhCkd4wr+hgDtuxxi1Rkpn WvMjnMdJMhWMkyETqbRbmGHaQg7QVhzW15MAkXgIMhgfH6px5KEsTbRnJlHYePY3dmbZwub+3EJFn VoTMq7pLiGeW5+Ytg3N/GchGICPxmp+mn2SzwyDGShHa3UdD/h5wGj+yNYTQRsh2X/isgBAOfRWYa QpDGlH4bQR6Vtjrozmt0lhENfx+Evj2JqLHbf2Idbo/xkNnblGpg3bdy8ycEpkKg==; Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94.2) (envelope-from ) id 1mGFgz-00CbW0-CL; Wed, 18 Aug 2021 09:08:53 +0200 Message-ID: <11db2cdc5316b51f3fa2f34e813a458e455c763d.camel@sipsolutions.net> Subject: Re: [PATCH v2 44/63] mac80211: Use memset_after() to clear tx status From: Johannes Berg To: Kees Cook , linux-kernel@vger.kernel.org Cc: "David S. Miller" , Jakub Kicinski , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, "Gustavo A. R. Silva" , Greg Kroah-Hartman , Andrew Morton , dri-devel@lists.freedesktop.org, linux-staging@lists.linux.dev, linux-block@vger.kernel.org, linux-kbuild@vger.kernel.org, clang-built-linux@googlegroups.com, Rasmus Villemoes , linux-hardening@vger.kernel.org Date: Wed, 18 Aug 2021 09:08:52 +0200 In-Reply-To: <20210818060533.3569517-45-keescook@chromium.org> References: <20210818060533.3569517-1-keescook@chromium.org> <20210818060533.3569517-45-keescook@chromium.org> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.38.4 (3.38.4-1.fc33) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-malware-bazaar: not-scanned Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2021-08-17 at 23:05 -0700, Kees Cook wrote: > > @@ -275,12 +275,11 @@ static void carl9170_tx_release(struct kref *ref) >   if (WARN_ON_ONCE(!ar)) >   return; >   > > > > - BUILD_BUG_ON( > - offsetof(struct ieee80211_tx_info, status.ack_signal) != 20); > - > - memset(&txinfo->status.ack_signal, 0, > - sizeof(struct ieee80211_tx_info) - > - offsetof(struct ieee80211_tx_info, status.ack_signal)); > + /* > + * Should this call ieee80211_tx_info_clear_status() instead of clearing > + * manually? txinfo->status.rates do not seem to be used here. > + */ Since you insist, I went digging :) It should not, carl9170_tx_fill_rateinfo() has filled the rate information before we get to this point. johannes