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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 A96CAC4363C for ; Wed, 7 Oct 2020 11:48:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 55A96206F4 for ; Wed, 7 Oct 2020 11:48:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728018AbgJGLsu (ORCPT ); Wed, 7 Oct 2020 07:48:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34980 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726096AbgJGLst (ORCPT ); Wed, 7 Oct 2020 07:48:49 -0400 Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2FFBCC061755; Wed, 7 Oct 2020 04:48:49 -0700 (PDT) Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94) (envelope-from ) id 1kQ7w5-000t7x-Bn; Wed, 07 Oct 2020 13:48:45 +0200 Message-ID: Subject: Re: [PATCH 0/2] net, mac80211: enable KCOV remote coverage collection for 802.11 frame handling From: Johannes Berg To: Aleksandr Nogikh , davem@davemloft.net, kuba@kernel.org Cc: edumazet@google.com, andreyknvl@google.com, dvyukov@google.com, elver@google.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-wireless@vger.kernel.org, nogikh@google.com Date: Wed, 07 Oct 2020 13:48:43 +0200 In-Reply-To: <20201007101726.3149375-1-a.nogikh@gmail.com> (sfid-20201007_121750_390860_16179DAD) References: <20201007101726.3149375-1-a.nogikh@gmail.com> (sfid-20201007_121750_390860_16179DAD) Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.5 (3.36.5-1.fc32) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2020-10-07 at 10:17 +0000, Aleksandr Nogikh wrote: > From: Aleksandr Nogikh > > This patch series enables remote KCOV coverage collection for the > mac80211 code that processes incoming 802.11 frames. These changes > make it possible to perform coverage-guided fuzzing in search of > remotely triggerable bugs. > > > The series consists of two commits. > 1. Remember kcov_handle for each sk_buff. This can later be used to > enable remote coverage for other network subsystems. > 2. Annotate the code that processes incoming 802.11 frames. > > Aleksandr Nogikh (2): > net: store KCOV remote handle in sk_buff Can you explain that a bit better? What is a "remote handle"? What does it do in the SKB? I guess I'd have to know more about "kcov_common_handle()" to understand this bit. > mac80211: add KCOV remote annotations to incoming frame processing This seems fine, but a bit too limited? You tagged only ieee80211_tasklet_handler() which calls ieee80211_rx() or ieee80211_tx_status(), but 1) I'm not even sure ieee80211_tx_status() counts (it's processing locally generated frames after they round-tripped into the driver (although in mesh it could be remote originated but retransmitted frames, so I guess it makes some sense?); and 2) there are many other ways that ieee80211_rx() could get called. It seems to me it'd make more sense to (also) annotate ieee80211_rx() itself? johannes