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 7F513C433FE for ; Wed, 16 Nov 2022 07:37:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230417AbiKPHhC (ORCPT ); Wed, 16 Nov 2022 02:37:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49064 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233075AbiKPHg2 (ORCPT ); Wed, 16 Nov 2022 02:36:28 -0500 Received: from mail-pl1-x62b.google.com (mail-pl1-x62b.google.com [IPv6:2607:f8b0:4864:20::62b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E294013D3E; Tue, 15 Nov 2022 23:35:42 -0800 (PST) Received: by mail-pl1-x62b.google.com with SMTP id y4so15676061plb.2; Tue, 15 Nov 2022 23:35:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=dfcUfIC+n8vuBd2oNUY05LgFgo0EmYT0jFwMTSVR4p4=; b=jU9TyiKsLljpWLipGvQPKjltF9dl6uz2tKBKMP0EZqI8MRukRZfldprZ7TQj4sepBX XSLKQOybHbmbb4OWFF65GrLHvSL82VNzSdkYuM78SKF7L313mc0G66PtOGq/o2Co227j 5gpXx6L1GykdEIDX6zYDOlXYALjP7x9IBb1OYG3iRT8cEJHWYVUC7ryvqX9Y/c6yI1aa 0Rtx34JrRm7BzGLVeibdLdVOSspiwA42YmTBuisdxyMPA5G7/5DKLYAcnj6RDoiZdPpe Ws9mZcLhve1PGCbC7xuo3UPWsb+VH0EquX52Fez/ERaImJ1v0Bm8pju3cmA8M1UXbRBV Jz3g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=dfcUfIC+n8vuBd2oNUY05LgFgo0EmYT0jFwMTSVR4p4=; b=fdq1owFT0ekD0Eeu0fEbi1xnBC6aal0lHKLOEVMKr6YWGscnkLrkyU9UCI3QpFVNB9 uPSTzq+i3VL0J48dXR2fHuTf0GVzcKzNsXRq1z2sOgQss/VA8IKZjx3r7uf38ZNyVKXG /aZksCIbS2ZjfVb1XBQyAV4ZpJRNFru42yL8t4P/PAdKyW2LauAjfbgu7VSZ0AEvz2Jz Id7MLBNR7++6NkelT4RVh7ytDTRdoLNZse3oR6cNtwHbsz6KaHRe7uwZItw1f951+6V4 pJ5u9QHHYN45QZt6ayEHper64+xJiu8SZeX8LZeZQeGxgX8kbe4ZpaPDyzFo9nEP9tn+ e96A== X-Gm-Message-State: ANoB5pmbGvPSfMVuLQid66iz81iV3DUxDkaqkwsNZpd95uXLYq00F5Ps Ag//qWXfo5cWnzJ5PR0FxB8= X-Google-Smtp-Source: AA0mqf53kLI+++l/bYl0r6Ko0vXF2UDZRvG2xG3dkGQtk+URH2a9moMmEGZxLXjCKz+vV0ZLwcBumA== X-Received: by 2002:a17:902:7404:b0:186:75f0:331c with SMTP id g4-20020a170902740400b0018675f0331cmr7917459pll.161.1668584142340; Tue, 15 Nov 2022 23:35:42 -0800 (PST) Received: from localhost ([114.254.0.245]) by smtp.gmail.com with ESMTPSA id i65-20020a628744000000b0056b6c7a17c6sm10487264pfe.12.2022.11.15.23.35.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Nov 2022 23:35:41 -0800 (PST) From: Hawkins Jiawei To: kuba@kernel.org Cc: 18801353760@163.com, cong.wang@bytedance.com, davem@davemloft.net, edumazet@google.com, jhs@mojatatu.com, jiri@resnulli.us, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, syzbot+232ebdbd36706c965ebf@syzkaller.appspotmail.com, syzkaller-bugs@googlegroups.com, xiyou.wangcong@gmail.com, yin31149@gmail.com Subject: Re: [PATCH v2] net: sched: fix memory leak in tcindex_set_parms Date: Wed, 16 Nov 2022 15:35:22 +0800 Message-Id: <20221116073522.80304-1-yin31149@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221115090237.5d5988bb@kernel.org> References: <20221115090237.5d5988bb@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Wed, 16 Nov 2022 at 01:02, Jakub Kicinski wrote: > > On Mon, 14 Nov 2022 01:05:08 +0800 Hawkins Jiawei wrote: > > diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c > > index 1c9eeb98d826..d2fac9559d3e 100644 > > --- a/net/sched/cls_tcindex.c > > +++ b/net/sched/cls_tcindex.c > > @@ -338,6 +338,7 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base, > >       struct tcf_result cr = {}; > >       int err, balloc = 0; > >       struct tcf_exts e; > > +     struct tcf_exts old_e = {}; > > This is not a valid way of initializing a structure. > tcf_exts_init() is supposed to be called. > If we add a list member to that structure this code will break, again. Yes, you are right. But the `old_e` variable here is used only for freeing old_r->exts resource, `old_e` will be overwritten by old_r->exts content as follows: struct tcf_exts old_e = {}; ... if (old_r && old_r != r) {         old_e = old_r->exts; ... } ... synchronize_rcu(); tcf_exts_destroy(&old_e); So this patch uses `struct tcf_exts old_e = {}` here just for a cleared space.