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=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 8F5B8C3A59D for ; Mon, 19 Aug 2019 08:23:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6EB032082C for ; Mon, 19 Aug 2019 08:23:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727126AbfHSIXF (ORCPT ); Mon, 19 Aug 2019 04:23:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40070 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725536AbfHSIXE (ORCPT ); Mon, 19 Aug 2019 04:23:04 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 49A39195C2E8; Mon, 19 Aug 2019 08:23:04 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-120-255.rdu2.redhat.com [10.10.120.255]) by smtp.corp.redhat.com (Postfix) with ESMTP id 24DF8104B4ED; Mon, 19 Aug 2019 08:23:01 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <20190819071101.5796-1-hdanton@sina.com> References: <20190819071101.5796-1-hdanton@sina.com> To: Hillf Danton Cc: dhowells@redhat.com, syzbot , davem@davemloft.net, dvyukov@google.com, ebiggers@kernel.org, linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: kernel BUG at net/rxrpc/local_object.c:LINE! MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <21981.1566202980.1@warthog.procyon.org.uk> Date: Mon, 19 Aug 2019 09:23:00 +0100 Message-ID: <21982.1566202980@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.62]); Mon, 19 Aug 2019 08:23:04 +0000 (UTC) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hi Hillf, There are some commits in net/master that ought to fix this and conflict with your longer patch: 730c5fd42c1e3652a065448fd235cb9fafb2bd10 rxrpc: Fix local endpoint refcounting 68553f1a6f746bf860bce3eb42d78c26a717d9c0 rxrpc: Fix local refcounting b00df840fb4004b7087940ac5f68801562d0d2de rxrpc: Fix local endpoint replacement 06d9532fa6b34f12a6d75711162d47c17c1add72 rxrpc: Fix read-after-free in rxrpc_queue_local() After the first one, you should never see local->usage == 0 in rxrpc_input_packet() as the UDP socket gets closed before the refcount is reduced to 0 (there's now a second "usage" count that counts how many times the local endpoint is in use and local->usage is the refcount for the struct itself). Thanks, David