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 2A618C4724C for ; Fri, 1 May 2020 13:42:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 08C0A2173E for ; Fri, 1 May 2020 13:42:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588340569; bh=Tgvy8L/qcTQAd0WfpP+tRSfrskJUjHDc5vwMG2Vn+uA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=HxowgD6aQXIGKZFtNHWvpOBVkUYjE/Y9MqVfSGhtgwa+XCI65xdW5Kt3frBMwP1kP P9tkvgCLE7J9YQRnpRmFI+a5Z85go9+uxWTlPmorNw8rVhyTD66CENotGP5I5NIVV8 HjEzH6iW8eLeb0oK4LSHkpQVLk1NGXDMD2R/4qSQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731551AbgEANmr (ORCPT ); Fri, 1 May 2020 09:42:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:43476 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731548AbgEANmo (ORCPT ); Fri, 1 May 2020 09:42:44 -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 36EFC205C9; Fri, 1 May 2020 13:42:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588340563; bh=Tgvy8L/qcTQAd0WfpP+tRSfrskJUjHDc5vwMG2Vn+uA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rPK7shIoIQTI5i22g1QXWjiWimpbDNvNizyDGPcNoTsrPpQJnKDTZBXP+RjAFULiB /msuLjusjpUGHe671avQuSsHkYrcyLi77zlRsgodBBB/B15veVUzsjEO8pAGFC5uNF vKvx7+bSoX5v4KE1xmCsKXuCxbk/tssezbzSCsTg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Howells , "David S. Miller" Subject: [PATCH 5.6 033/106] rxrpc: Fix DATA Tx to disable nofrag for UDP on AF_INET6 socket Date: Fri, 1 May 2020 15:23:06 +0200 Message-Id: <20200501131547.931293506@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200501131543.421333643@linuxfoundation.org> References: <20200501131543.421333643@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: David Howells commit 0e631eee17dcea576ab922fa70e4fdbd596ee452 upstream. Fix the DATA packet transmission to disable nofrag for UDPv4 on an AF_INET6 socket as well as UDPv6 when trying to transmit fragmentably. Without this, packets filled to the normal size used by the kernel AFS client of 1412 bytes be rejected by udp_sendmsg() with EMSGSIZE immediately. The ->sk_error_report() notification hook is called, but rxrpc doesn't generate a trace for it. This is a temporary fix; a more permanent solution needs to involve changing the size of the packets being filled in accordance with the MTU, which isn't currently done in AF_RXRPC. The reason for not doing so was that, barring the last packet in an rx jumbo packet, jumbos can only be assembled out of 1412-byte packets - and the plan was to construct jumbos on the fly at transmission time. Also, there's no point turning on IPV6_MTU_DISCOVER, since IPv6 has to engage in this anyway since fragmentation is only done by the sender. We can then condense the switch-statement in rxrpc_send_data_packet(). Fixes: 75b54cb57ca3 ("rxrpc: Add IPv6 support") Signed-off-by: David Howells Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/rxrpc/local_object.c | 9 --------- net/rxrpc/output.c | 42 +++++++++++------------------------------- 2 files changed, 11 insertions(+), 40 deletions(-) --- a/net/rxrpc/local_object.c +++ b/net/rxrpc/local_object.c @@ -165,15 +165,6 @@ static int rxrpc_open_socket(struct rxrp goto error; } - /* we want to set the don't fragment bit */ - opt = IPV6_PMTUDISC_DO; - ret = kernel_setsockopt(local->socket, SOL_IPV6, IPV6_MTU_DISCOVER, - (char *) &opt, sizeof(opt)); - if (ret < 0) { - _debug("setsockopt failed"); - goto error; - } - /* Fall through and set IPv4 options too otherwise we don't get * errors from IPv4 packets sent through the IPv6 socket. */ --- a/net/rxrpc/output.c +++ b/net/rxrpc/output.c @@ -474,41 +474,21 @@ send_fragmentable: skb->tstamp = ktime_get_real(); switch (conn->params.local->srx.transport.family) { + case AF_INET6: case AF_INET: opt = IP_PMTUDISC_DONT; - ret = kernel_setsockopt(conn->params.local->socket, - SOL_IP, IP_MTU_DISCOVER, - (char *)&opt, sizeof(opt)); - if (ret == 0) { - ret = kernel_sendmsg(conn->params.local->socket, &msg, - iov, 2, len); - conn->params.peer->last_tx_at = ktime_get_seconds(); - - opt = IP_PMTUDISC_DO; - kernel_setsockopt(conn->params.local->socket, SOL_IP, - IP_MTU_DISCOVER, - (char *)&opt, sizeof(opt)); - } - break; - -#ifdef CONFIG_AF_RXRPC_IPV6 - case AF_INET6: - opt = IPV6_PMTUDISC_DONT; - ret = kernel_setsockopt(conn->params.local->socket, - SOL_IPV6, IPV6_MTU_DISCOVER, - (char *)&opt, sizeof(opt)); - if (ret == 0) { - ret = kernel_sendmsg(conn->params.local->socket, &msg, - iov, 2, len); - conn->params.peer->last_tx_at = ktime_get_seconds(); + kernel_setsockopt(conn->params.local->socket, + SOL_IP, IP_MTU_DISCOVER, + (char *)&opt, sizeof(opt)); + ret = kernel_sendmsg(conn->params.local->socket, &msg, + iov, 2, len); + conn->params.peer->last_tx_at = ktime_get_seconds(); - opt = IPV6_PMTUDISC_DO; - kernel_setsockopt(conn->params.local->socket, - SOL_IPV6, IPV6_MTU_DISCOVER, - (char *)&opt, sizeof(opt)); - } + opt = IP_PMTUDISC_DO; + kernel_setsockopt(conn->params.local->socket, + SOL_IP, IP_MTU_DISCOVER, + (char *)&opt, sizeof(opt)); break; -#endif default: BUG();