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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 36E33C43331 for ; Wed, 1 Apr 2020 16:24:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0110E20857 for ; Wed, 1 Apr 2020 16:24:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585758246; bh=6kmzOfKlvodBmbyU6T7UJ/bnCnSCfu18QH7zz18a3lI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=bw3Sc9CpLyD78Zgl9lTPYD+9BryqQpaGtUlCt0NdSJEGL7vVfckLbX60BYEuuMdYP uEPji/o47ZFtcJL35XbxIpZ4xClPGZMEXPLkBSDSBKlf7RAYAHW2sITCTHimja2XA/ gc6pvDKr4161KgHffXtyq1Ibm3ACUJ1vBS3pmdjg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733280AbgDAQYE (ORCPT ); Wed, 1 Apr 2020 12:24:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:47550 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732286AbgDAQYC (ORCPT ); Wed, 1 Apr 2020 12:24:02 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 169DF21744; Wed, 1 Apr 2020 16:24:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585758241; bh=6kmzOfKlvodBmbyU6T7UJ/bnCnSCfu18QH7zz18a3lI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pROjNTrtHmQKr4pYkSRcmcbvElPteWfl+N9lnN9L7L8K/2I0mIKOWftnZUSIunqQa gttcJBBoAlUBA9ZUfkNI7zdD9MYKtbMz4lJAHRdNP53wxYxDH92yWpT6O/WaJ3dXX5 rwSzPriZ1kl6WMWXDDyXGym8qsOi05vboDvgmHsM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , syzbot , "David S. Miller" Subject: [PATCH 4.19 028/116] tcp: repair: fix TCP_QUEUE_SEQ implementation Date: Wed, 1 Apr 2020 18:16:44 +0200 Message-Id: <20200401161545.988970668@linuxfoundation.org> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200401161542.669484650@linuxfoundation.org> References: <20200401161542.669484650@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Dumazet [ Upstream commit 6cd6cbf593bfa3ae6fc3ed34ac21da4d35045425 ] When application uses TCP_QUEUE_SEQ socket option to change tp->rcv_next, we must also update tp->copied_seq. Otherwise, stuff relying on tcp_inq() being precise can eventually be confused. For example, tcp_zerocopy_receive() might crash because it does not expect tcp_recv_skb() to return NULL. We could add tests in various places to fix the issue, or simply make sure tcp_inq() wont return a random value, and leave fast path as it is. Note that this fixes ioctl(fd, SIOCINQ, &val) at the same time. Fixes: ee9952831cfd ("tcp: Initial repair mode") Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/tcp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2870,8 +2870,10 @@ static int do_tcp_setsockopt(struct sock err = -EPERM; else if (tp->repair_queue == TCP_SEND_QUEUE) tp->write_seq = val; - else if (tp->repair_queue == TCP_RECV_QUEUE) + else if (tp->repair_queue == TCP_RECV_QUEUE) { WRITE_ONCE(tp->rcv_nxt, val); + WRITE_ONCE(tp->copied_seq, val); + } else err = -EINVAL; break;