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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 57A6BC10F03 for ; Tue, 23 Apr 2019 16:55:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1568921738 for ; Tue, 23 Apr 2019 16:55:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729026AbfDWQzd convert rfc822-to-8bit (ORCPT ); Tue, 23 Apr 2019 12:55:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52310 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728526AbfDWQzc (ORCPT ); Tue, 23 Apr 2019 12:55:32 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B20F25277B; Tue, 23 Apr 2019 16:55:32 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-121-98.rdu2.redhat.com [10.10.121.98]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9A4E0608A4; Tue, 23 Apr 2019 16:55:29 +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: <20190423155020.164082-1-edumazet@google.com> References: <20190423155020.164082-1-edumazet@google.com> To: Eric Dumazet Cc: dhowells@redhat.com, "David S . Miller" , netdev , Eric Dumazet , syzbot Subject: Re: [PATCH net] rxrpc: fix race condition in rxrpc_input_packet() MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <21267.1556038528.1@warthog.procyon.org.uk> Content-Transfer-Encoding: 8BIT Date: Tue, 23 Apr 2019 17:55:28 +0100 Message-ID: <21268.1556038528@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Tue, 23 Apr 2019 16:55:32 +0000 (UTC) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Eric Dumazet wrote: > @@ -1181,6 +1177,9 @@ int rxrpc_input_packet(struct sock *udp_sk, struct sk_buff *skb) > > _enter("%p", udp_sk); > > + if (!local) > + return -ENOENT; > + > This looks wrong. Did you mean "return -AF_INET"? The comment in net/ipv6/udp.c says: /* * This is an encapsulation socket so pass the skb to * the socket's udp_encap_rcv() hook. Otherwise, just * fall through and pass this up the UDP socket. * up->encap_rcv() returns the following value: * =0 if skb was successfully passed to the encap * handler or was discarded by it. * >0 if skb should be passed on to UDP. * <0 if skb should be resubmitted as proto -N */ This suggests that -ENOENT is not a valid return. Should you "goto discard" instead - or just discard the packet and return 0? David