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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, 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 D0588C433E0 for ; Wed, 20 May 2020 15:51:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9C2552070A for ; Wed, 20 May 2020 15:51:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=networkplumber-org.20150623.gappssmtp.com header.i=@networkplumber-org.20150623.gappssmtp.com header.b="VBDVFrk6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726812AbgETPvE (ORCPT ); Wed, 20 May 2020 11:51:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40738 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726650AbgETPvE (ORCPT ); Wed, 20 May 2020 11:51:04 -0400 Received: from mail-pj1-x1043.google.com (mail-pj1-x1043.google.com [IPv6:2607:f8b0:4864:20::1043]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3B114C061A0E for ; Wed, 20 May 2020 08:51:04 -0700 (PDT) Received: by mail-pj1-x1043.google.com with SMTP id s69so1477380pjb.4 for ; Wed, 20 May 2020 08:51:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=PGt5BLdFYxU6z1cqTJIqi+js4tZYCy5XiqwrbJue7TA=; b=VBDVFrk6oKnVNDIw8raagKq5a8eJuK45dEaNEJhAanbz91rxFKnrQTllLBUsf1VmYC NoqgnZ2zzAHzxt/ftq82ycjy2pqQDQCGwnNPuNsAedzasPPDynnRSobblUVi2uAjP81x dloti4nJ8TCEoIefrSsNa+yBd5be88qsolNL9eu+S30O7URyhU7bdMrCvhOIgp/x2nh8 VaJJHi5duJo24MpKRBmNnqCLc/OoeNEceeU7MEBsNfXTkm9fRGgI4MpAQZUCvNZfpOjZ aj/YNjC383Z9TeAONWCxS25M+59WYmG0oUtYGird2unKBRZuTIzj3PUiAQJTAtNiMlh/ rSTQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=PGt5BLdFYxU6z1cqTJIqi+js4tZYCy5XiqwrbJue7TA=; b=AHQ6eQ5ojO86n0J4iRw2L/JyW/CanyokwRNXj+gbIHz6yL/nDuKfGvVHi1Yrx08yaV IZevlkOQcsEZ31xC2KdQXJUiIlHsfe8EgIlUaiOx1vVMM68O+LxTJgq7Jy/r6A59uWii ZSUYWwImaN0qsDRblw1l+wkbBrquCcGgh/8YiVT1QuiQ2nb17aZcomBcus2/9yiahbSY 7Bgy6oHHB4VzBaF33/Jl+6cZdAAmBhOExLG+rfwFOO3hFdBXaA1/xx9d1+K51ZafexXd S07+Z017n33V2vcPML+/QLXr8p3K5v9HUhx8BTrhsFK96/UegpUmTozRSXaNgTZNGAAK kE1g== X-Gm-Message-State: AOAM531Pj8B1WVww0OlmDjUh3IKwN6c6iuNS1e0Yw75rRmyYOv0iUQd3 AWx8Kd/vzCmZ16ZiaeK5JXOAzg== X-Google-Smtp-Source: ABdhPJx04CU5osC8N8WwltpLcZT/kJVkSQfwexK2sh11BxrJR6el86m4PMpCODbiTjaQgxTmnH5d/A== X-Received: by 2002:a17:902:9342:: with SMTP id g2mr5279742plp.326.1589989863733; Wed, 20 May 2020 08:51:03 -0700 (PDT) Received: from hermes.lan (204-195-22-127.wavecable.com. [204.195.22.127]) by smtp.gmail.com with ESMTPSA id w19sm2343277pfc.95.2020.05.20.08.51.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 May 2020 08:51:03 -0700 (PDT) Date: Wed, 20 May 2020 08:50:54 -0700 From: Stephen Hemminger To: Nikolay Aleksandrov Cc: netdev@vger.kernel.org, roopa@cumulusnetworks.com, davem@davemloft.net, bridge@lists.linux-foundation.org, syzkaller-bugs@googlegroups.com Subject: Re: [PATCH net v3] net: bridge: fix vlan stats use-after-free on destruction Message-ID: <20200520085054.2031ad8a@hermes.lan> In-Reply-To: <20181116165001.30896-1-nikolay@cumulusnetworks.com> References: <20181114172703.5795-1-nikolay@cumulusnetworks.com> <20181116165001.30896-1-nikolay@cumulusnetworks.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Fri, 16 Nov 2018 18:50:01 +0200 Nikolay Aleksandrov wrote: > + if (v->priv_flags & BR_VLFLAG_PER_PORT_STATS) > free_percpu(v->stats); Why not not v->stats == NULL as a flag instead? Then the fact that free_percpu(NULL) is a Nop would mean less code in the bridge driver.