From patchwork Wed May 12 01:31:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Sanger X-Patchwork-Id: 436166 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 AAEE2C433B4 for ; Wed, 12 May 2021 01:32:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E90F6191D for ; Wed, 12 May 2021 01:32:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230019AbhELBde (ORCPT ); Tue, 11 May 2021 21:33:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57908 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229934AbhELBdd (ORCPT ); Tue, 11 May 2021 21:33:33 -0400 Received: from warlock.wand.net.nz (warlock.cms.waikato.ac.nz [IPv6:2001:df0:4:4000::250:15]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C61AFC061574 for ; Tue, 11 May 2021 18:32:24 -0700 (PDT) Received: from [2001:df0:4:4000:4db9:d736:1d15:94f4] (helo=mantra.wand.net.nz) by warlock.wand.net.nz with esmtpsa (TLS1.2:RSA_AES_128_CBC_SHA256:128) (Exim 4.84_2) (envelope-from ) id 1lgdja-0002Sb-76; Wed, 12 May 2021 13:32:22 +1200 From: Richard Sanger To: netdev@vger.kernel.org Cc: Richard Sanger , Daniel Borkmann , Willem de Bruijn Subject: [PATCH v2] net: packetmmap: fix only tx timestamp on request Date: Wed, 12 May 2021 13:31:22 +1200 Message-Id: <1620783082-28906-1-git-send-email-rsanger@wand.net.nz> X-Mailer: git-send-email 2.7.4 Received-SPF: pass client-ip=2001:df0:4:4000:4db9:d736:1d15:94f4; envelope-from=rsanger@wand.net.nz; helo=mantra.wand.net.nz Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The packetmmap tx ring should only return timestamps if requested via setsockopt PACKET_TIMESTAMP, as documented. This allows compatibility with non-timestamp aware user-space code which checks tp_status == TP_STATUS_AVAILABLE; not expecting additional timestamp flags to be set in tp_status. Fixes: b9c32fb27170 ("packet: if hw/sw ts enabled in rx/tx ring, report which ts we got") Cc: Daniel Borkmann Cc: Willem de Bruijn Signed-off-by: Richard Sanger --- net/packet/af_packet.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index ba96db1..ae906eb 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -422,7 +422,8 @@ static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec64 *ts, ktime_to_timespec64_cond(shhwtstamps->hwtstamp, ts)) return TP_STATUS_TS_RAW_HARDWARE; - if (ktime_to_timespec64_cond(skb->tstamp, ts)) + if ((flags & SOF_TIMESTAMPING_SOFTWARE) && + ktime_to_timespec64_cond(skb->tstamp, ts)) return TP_STATUS_TS_SOFTWARE; return 0; @@ -2340,7 +2341,12 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, skb_copy_bits(skb, 0, h.raw + macoff, snaplen); - if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp))) + /* Always timestamp; prefer an existing software timestamp taken + * closer to the time of capture. + */ + ts_status = tpacket_get_timestamp(skb, &ts, + po->tp_tstamp | SOF_TIMESTAMPING_SOFTWARE); + if (!ts_status) ktime_get_real_ts64(&ts); status |= ts_status;