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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 18987C43381 for ; Fri, 22 Mar 2019 12:24:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DAE5B2054F for ; Fri, 22 Mar 2019 12:24:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553257450; bh=rRFDhO6/osI/i2WvAr/Hm1Nvwwi5Ep1TzT5bDvZayPc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=x7FKzpOFIKQYw1JgHtqDMZKf5dBf+8VkoflxmCGTZUpaS/zn1xOwBuzRXVSFxS7EF LduSaM6FfmCPIYeeK4VjFN6QHI07ItyX5DhsEaecZspuqfTDnHUuw1aY5E7nQgbOo7 Y1cRDWwkXVpAmnfWbOkBEpQ/LpardAPRX1CqueyI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391238AbfCVMYJ (ORCPT ); Fri, 22 Mar 2019 08:24:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:35832 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391230AbfCVMYG (ORCPT ); Fri, 22 Mar 2019 08:24:06 -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 2581D218A1; Fri, 22 Mar 2019 12:24:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553257445; bh=rRFDhO6/osI/i2WvAr/Hm1Nvwwi5Ep1TzT5bDvZayPc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JC7cKfIPUqyhq1NEkUL7Qnnn08o4FDK8fYUG1hP/1AbUdHfYVDrGBybuQVkHktFyk DIgNMk/uPd6c+8aCsyyh9SKrvskWNGGRdMmfxiZJzP3BUBuS6GIu9Km/5eYJF+2lZ6 CzxG5OVpaVQLUBY7ufVRtT+//518Zx9djvOwpEAw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, James Pearson , "J. Bruce Fields" Subject: [PATCH 5.0 191/238] svcrpc: fix UDP on servers with lots of threads Date: Fri, 22 Mar 2019 12:16:50 +0100 Message-Id: <20190322111309.483760539@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190322111258.383569278@linuxfoundation.org> References: <20190322111258.383569278@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore 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 5.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: J. Bruce Fields commit b7e5034cbecf5a65b7bfdc2b20a8378039577706 upstream. James Pearson found that an NFS server stopped responding to UDP requests if started with more than 1017 threads. sv_max_mesg is about 2^20, so that is probably where the calculation performed by svc_sock_setbufsize(svsk->sk_sock, (serv->sv_nrthreads+3) * serv->sv_max_mesg, (serv->sv_nrthreads+3) * serv->sv_max_mesg); starts to overflow an int. Reported-by: James Pearson Tested-by: James Pearson Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields Signed-off-by: Greg Kroah-Hartman --- net/sunrpc/svcsock.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -349,12 +349,16 @@ static ssize_t svc_recvfrom(struct svc_r /* * Set socket snd and rcv buffer lengths */ -static void svc_sock_setbufsize(struct socket *sock, unsigned int snd, - unsigned int rcv) +static void svc_sock_setbufsize(struct svc_sock *svsk, unsigned int nreqs) { + unsigned int max_mesg = svsk->sk_xprt.xpt_server->sv_max_mesg; + struct socket *sock = svsk->sk_sock; + + nreqs = min(nreqs, INT_MAX / 2 / max_mesg); + lock_sock(sock->sk); - sock->sk->sk_sndbuf = snd * 2; - sock->sk->sk_rcvbuf = rcv * 2; + sock->sk->sk_sndbuf = nreqs * max_mesg * 2; + sock->sk->sk_rcvbuf = nreqs * max_mesg * 2; sock->sk->sk_write_space(sock->sk); release_sock(sock->sk); } @@ -516,9 +520,7 @@ static int svc_udp_recvfrom(struct svc_r * provides an upper bound on the number of threads * which will access the socket. */ - svc_sock_setbufsize(svsk->sk_sock, - (serv->sv_nrthreads+3) * serv->sv_max_mesg, - (serv->sv_nrthreads+3) * serv->sv_max_mesg); + svc_sock_setbufsize(svsk, serv->sv_nrthreads + 3); clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); skb = NULL; @@ -681,9 +683,7 @@ static void svc_udp_init(struct svc_sock * receive and respond to one request. * svc_udp_recvfrom will re-adjust if necessary */ - svc_sock_setbufsize(svsk->sk_sock, - 3 * svsk->sk_xprt.xpt_server->sv_max_mesg, - 3 * svsk->sk_xprt.xpt_server->sv_max_mesg); + svc_sock_setbufsize(svsk, 3); /* data might have come in before data_ready set up */ set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);