From patchwork Wed Oct 7 11:42:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Magnus Karlsson X-Patchwork-Id: 11820465 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=-12.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 46F04C4363D for ; Wed, 7 Oct 2020 11:42:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DE79C2064E for ; Wed, 7 Oct 2020 11:42:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="OsHUIYjt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727958AbgJGLmk (ORCPT ); Wed, 7 Oct 2020 07:42:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34046 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726096AbgJGLmk (ORCPT ); Wed, 7 Oct 2020 07:42:40 -0400 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 01E51C061755; Wed, 7 Oct 2020 04:42:40 -0700 (PDT) Received: by mail-pf1-x443.google.com with SMTP id 144so1188411pfb.4; Wed, 07 Oct 2020 04:42:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=xAQFlFHy7kWTivT3gKpMF/fe7kfqKwykruPRIM+JP+w=; b=OsHUIYjtaje0JVubDFXPk/qDcZ4BUmqedfX1JkvGYUzXo0yKFOMIOpgZUdvqquK2Hs Mbux//Fs5gLRjA9dJdrdrMmy++Q1p7y0cCLY8VO4vG87bTc+UDJbd8++boFzncLZxJOs /sCwzSuqqSlx/5UmYdMb6Att0cDUvesBJjIlsTPGAdJMU1q3WC6/G0Ddqo8gGcahvvFa aU01jStDpTQfAWZIUqQ2lfP2wihabr81FsOMO4o1qfxbqzK+zjXetp0CYrJSmgIYo43a +oAN8tzH2V/rRdiKzrQvb66PuOJbSeqIZqawZ8l2sALr1zvd41fBdrRAdjBtyHRMif+m OIog== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=xAQFlFHy7kWTivT3gKpMF/fe7kfqKwykruPRIM+JP+w=; b=jZm03tlvzBLdXYUXUDp4tV9c5J4Y1sLTsyA/iztFCBRfFhbISFN30CraSgrQN12eMz oaYpb7MXwiopfeEyLk6Q+FgsL2aN+/dOqTXrqfsA0pbvnpcVjb4JmG0WlcFOCiZmBJwM tijzbijUWbCZ+VW/0Qh1EfZNip0U8jB8Jn7sYKmEYKwTKayRw6PpZk6mHdggn+ZCobSp 2m4AqXg+Vzmd1IAY8APheoGdSNrgf/4tE7sqSChAH4fx4j5sf+AyEzLbJ/q1Nwigfg/+ v4UXczaXQQtvSVxswM+zmtz9jIGfmEWJWhW2wNRjUOubGCVEcq8MWuhqBf7moOWF/xmC goAw== X-Gm-Message-State: AOAM5332IHXzvQhNEAriUL+GbYzhXzkFCsGrCN20BsJ0UK6w9oc8u2iK HInH/365yeuDWvbmFouU38k= X-Google-Smtp-Source: ABdhPJxKR1guD5qhOYd+sluidkIvw5ziHY9+v25uIh2JYZ2bt8OHTxPJvSoq4kl9WFY8R5OwjEe5LQ== X-Received: by 2002:a65:4885:: with SMTP id n5mr2781224pgs.63.1602070959551; Wed, 07 Oct 2020 04:42:39 -0700 (PDT) Received: from VM.ger.corp.intel.com (fmdmzpr03-ext.fm.intel.com. [192.55.54.38]) by smtp.gmail.com with ESMTPSA id x10sm2812259pfc.88.2020.10.07.04.42.36 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 07 Oct 2020 04:42:38 -0700 (PDT) From: Magnus Karlsson To: magnus.karlsson@intel.com, bjorn.topel@intel.com, ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org, jonathan.lemon@gmail.com Cc: bpf@vger.kernel.org, ciara.loftus@intel.com Subject: [PATCH bpf-next v2] libbpf: fix compatibility problem in xsk_socket__create Date: Wed, 7 Oct 2020 13:42:26 +0200 Message-Id: <1602070946-11154-1-git-send-email-magnus.karlsson@gmail.com> X-Mailer: git-send-email 2.7.4 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org From: Magnus Karlsson Fix a compatibility problem when the old XDP_SHARED_UMEM mode is used together with the xsk_socket__create() call. In the old XDP_SHARED_UMEM mode, only sharing of the same device and queue id was allowed, and in this mode, the fill ring and completion ring were shared between the AF_XDP sockets. Therefore, it was perfectly fine to call the xsk_socket__create() API for each socket and not use the new xsk_socket__create_shared() API. This behavior was ruined by the commit introducing XDP_SHARED_UMEM support between different devices and/or queue ids. This patch restores the ability to use xsk_socket__create in these circumstances so that backward compatibility is not broken. Fixes: 2f6324a3937f ("libbpf: Support shared umems between queues and devices") Signed-off-by: Magnus Karlsson --- v1->v2: * Removed the check for different fill or completion rings entered in xsk_umem__create and xsk_socket__create_shared. The current behavior, that the ones entered in xsk_socket__create_shared supersedes the ones in xsk_umem__create, should be kept. Will document this in a separate patch and show how it can make the application code path easier. --- tools/lib/bpf/xsk.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c index 30b4ca5..e3c98c0 100644 --- a/tools/lib/bpf/xsk.c +++ b/tools/lib/bpf/xsk.c @@ -705,7 +705,7 @@ int xsk_socket__create_shared(struct xsk_socket **xsk_ptr, struct xsk_ctx *ctx; int err, ifindex; - if (!umem || !xsk_ptr || !(rx || tx) || !fill || !comp) + if (!umem || !xsk_ptr || !(rx || tx)) return -EFAULT; xsk = calloc(1, sizeof(*xsk)); @@ -735,6 +735,11 @@ int xsk_socket__create_shared(struct xsk_socket **xsk_ptr, ctx = xsk_get_ctx(umem, ifindex, queue_id); if (!ctx) { + if (!fill || !comp) { + err = -EFAULT; + goto out_socket; + } + ctx = xsk_create_ctx(xsk, umem, ifindex, ifname, queue_id, fill, comp); if (!ctx) {