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, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 A2512C2BB1D for ; Mon, 16 Mar 2020 16:25:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7A6D12051A for ; Mon, 16 Mar 2020 16:25:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="gEZGx5bM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732113AbgCPQZb (ORCPT ); Mon, 16 Mar 2020 12:25:31 -0400 Received: from mail-vs1-f66.google.com ([209.85.217.66]:34549 "EHLO mail-vs1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731998AbgCPQZa (ORCPT ); Mon, 16 Mar 2020 12:25:30 -0400 Received: by mail-vs1-f66.google.com with SMTP id t10so11709325vsp.1; Mon, 16 Mar 2020 09:25:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=pnwZXZ1du5ptGIP0RI92ZrcWO3bFITyegjW7Cfo9dTs=; b=gEZGx5bMMtb5FZgdhnZhL6el3Q/sHueQ8j+MOyNe7o3aqNKRTQ4WD1/MPqW0QS6pW7 fIGtAVtkMRZZjD9BNSzW7lvrbYZh5binYY/cmUVrTIRmvRqKrzEr34njU9PsRbpDVb6V P7gox4FnHBdgp14Vojg4c0X6va7mB1nrbIzei3L5AGQeo0SAUwfbA/zIF+/OEWZ2H026 RwZFc6aNkGSnw0PmK+ulffrt+D6iqYzSt5veA7NzKKP+DTkJsZJCZZsF8G0mcrUUggtu fgc/vxcWsmu+MczxD+5IvQJ/eLA/VjtuJHuqF+8Uw5m0cqsDl9IbJD5QNI//6Ia//OTC TzSg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=pnwZXZ1du5ptGIP0RI92ZrcWO3bFITyegjW7Cfo9dTs=; b=EclGDFKpbMXYLvnvEFF1XTLgQb9Xh/3akPZfBO5HBZyusCeVS+fJQtSMa9tRWOwfPb zBL9yvSlsYdDV0+x5McpsJ2mm/ZP39Kd9mgDpyA+OMGNJUaQSukk1o3CadiHrhb3I88A fMRyS9MOvcZBJfMb6pzIIZrsJhrYY5fHFRkem1hsDWEzYKUDnbCSVkihI8gFP9umJm/6 cABY+fhzEX74aWM4USYzZc5Lg3NQ+uyG1e/LOveSZ7a9vAymbor/Lj6XnCPJz3Q3TeIy 0oLpUkOHN5e8SlCHgFzXImwBlXIcUADzIMGxCwi4DIYBCKWKTW8qJ5whgi309Cg6ktfk yUFQ== X-Gm-Message-State: ANhLgQ1Sp1IiOWQyDuRbRKmRv/X6h+K7hCup4uFHl+Bz7++u2Jxv8vJb E/LwaFp0lwSrCbvsAvFwPPTjf0JS72iLmehDmXw= X-Google-Smtp-Source: ADFU+vuShf577fz3GdMt08NSgjX9+ul39fkPKoJ1CyYXIzbNjuHgQaTE+keZ0kQzIysq+q5PgR2DhLHmZyonKHmccAA= X-Received: by 2002:a67:3201:: with SMTP id y1mr439544vsy.54.1584375927711; Mon, 16 Mar 2020 09:25:27 -0700 (PDT) MIME-Version: 1.0 References: <00000000000088452f05a07621d2@google.com> <000000000000cc985b05a07ce36f@google.com> <202003100900.1E2E399@keescook> <20200316155119.GB13004@willie-the-truck> In-Reply-To: <20200316155119.GB13004@willie-the-truck> From: Qiujun Huang Date: Tue, 17 Mar 2020 00:25:16 +0800 Message-ID: Subject: Re: WARNING: refcount bug in sctp_wfree To: Will Deacon Cc: Kees Cook , syzbot , ardb@kernel.org, davem@davemloft.net, guohanjun@huawei.com, kuba@kernel.org, linux-kernel@vger.kernel.org, linux-sctp@vger.kernel.org, marcelo.leitner@gmail.com, mingo@kernel.org, netdev@vger.kernel.org, nhorman@tuxdriver.com, syzkaller-bugs@googlegroups.com, vyasevich@gmail.com Content-Type: text/plain; charset="UTF-8" Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, Mar 16, 2020 at 11:52 PM Will Deacon wrote: > > On Tue, Mar 10, 2020 at 09:01:18AM -0700, Kees Cook wrote: > > On Tue, Mar 10, 2020 at 02:39:01AM -0700, syzbot wrote: > > > syzbot has bisected this bug to: > > > > > > commit fb041bb7c0a918b95c6889fc965cdc4a75b4c0ca > > > Author: Will Deacon > > > Date: Thu Nov 21 11:59:00 2019 +0000 > > > > > > locking/refcount: Consolidate implementations of refcount_t > > > > I suspect this is just bisecting to here because it made the refcount > > checks more strict? > > Yes, this is the commit that enables full refcount checking for all > architectures unconditionally, so it's the canary in the coalmine rather > than the source of the problem. Yes, I tracked it down. And sent out a fix: https://lore.kernel.org/netdev/1584330804-18477-1-git-send-email-hqjagain@gmail.com > > Will