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=-0.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 74128FA372A for ; Wed, 16 Oct 2019 10:34:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 572BF2168B for ; Wed, 16 Oct 2019 10:34:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392476AbfJPKet (ORCPT ); Wed, 16 Oct 2019 06:34:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41398 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392462AbfJPKet (ORCPT ); Wed, 16 Oct 2019 06:34:49 -0400 Received: from mail-lf1-f71.google.com (mail-lf1-f71.google.com [209.85.167.71]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BD53C81F0D for ; Wed, 16 Oct 2019 10:34:48 +0000 (UTC) Received: by mail-lf1-f71.google.com with SMTP id m16so4660153lfb.1 for ; Wed, 16 Oct 2019 03:34:48 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=SgWpfY5Xz4zDxp0MpMcVzJx2JBdy4PlhQXGqbdLqW1c=; b=cVz+kpyM9HHIUfT0r1LHMnzDSlZbmSdCsSTfzHYZG/0E4Oar2DFMd4kDb7rvc6ZC+C XPYvVtOL8qjcGsjQxqQiPTZ3wLtD+vw9ONKRBnZBH+iJtEJ/wbEuv732TXDnQEUk4FJX vliQNX6uIt2RJZDef3LG3CbkyUF8LAgoIatmIRw9RIe+9HP8gnrmT2cHV0QqCcOGhJgZ 1c/O4y26oIHnjjq9NErcNC6TpeoBCL/TFyWti1pbSUI3wEBKdXrCGp5ZayqxU2WPgCnk kAeLvEv8cJTW3/kLX/aEvB2D1/5z3W/O5Oga+nycYkQhhLpA9SXS+vEjJZyTdcSadgiN UhhA== X-Gm-Message-State: APjAAAWt6FTEXut3JllJ9SnSpbnrFaXXkz7qWcC8hwbJh4ydSgynr9L3 7Q2jBbI22OQJwTnR2c5he3u27YJGkEcUkL5kJhTCbBez0oTETbUuA72i+rUM5v16wTEATtqnK2C cGkIGOsqtTAxZWELB731zu4Sb X-Received: by 2002:a2e:8908:: with SMTP id d8mr25165972lji.197.1571222087232; Wed, 16 Oct 2019 03:34:47 -0700 (PDT) X-Google-Smtp-Source: APXvYqx4XYHDPAfrBOTyCsdEH7wCjKz6XyRUDaC+zt/SS3g8SNH7/oIXHGkUSk//39pfT1paBIYsMQ== X-Received: by 2002:a2e:8908:: with SMTP id d8mr25165952lji.197.1571222086968; Wed, 16 Oct 2019 03:34:46 -0700 (PDT) Received: from alrua-x1.borgediget.toke.dk (borgediget.toke.dk. [85.204.121.218]) by smtp.gmail.com with ESMTPSA id v1sm6234517lfq.89.2019.10.16.03.34.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Oct 2019 03:34:45 -0700 (PDT) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id 174401800F4; Wed, 16 Oct 2019 12:34:45 +0200 (CEST) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Alexei Starovoitov , Tetsuo Handa , Jesper Dangaard Brouer Cc: Alexei Starovoitov , Daniel Borkmann , syzbot , ddstreet@ieee.org, Dmitry Vyukov , LKML , Network Development , syzkaller-bugs , bpf Subject: Re: unregister_netdevice: waiting for DEV to become free (2) In-Reply-To: References: <00000000000056268e05737dcb95@google.com> <0000000000007d22100573d66078@google.com> <063a57ba-7723-6513-043e-ee99c5797271@I-love.SAKURA.ne.jp> X-Clacks-Overhead: GNU Terry Pratchett Date: Wed, 16 Oct 2019 12:34:45 +0200 Message-ID: <87imopgere.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Alexei Starovoitov writes: > On Fri, Oct 11, 2019 at 3:15 AM Tetsuo Handa > wrote: >> >> Hello. >> >> I noticed that syzbot is reporting that refcount incremented by bpf(BPF_MAP_UPDATE_ELEM) >> syscall is not decremented when unregister_netdevice() is called. Is this a BPF bug? > > Jesper, Toke, > please take a look. Yeah, that unregister notification handler definitely looks broken for hashmaps; I'll send a patch :) -Toke