From patchwork Wed Dec 9 13:26:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florent Revest X-Patchwork-Id: 11961383 X-Patchwork-Delegate: bpf@iogearbox.net 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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 ECD45C4361B for ; Wed, 9 Dec 2020 13:29:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AE5F023B45 for ; Wed, 9 Dec 2020 13:29:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727156AbgLIN3W (ORCPT ); Wed, 9 Dec 2020 08:29:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55018 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732310AbgLIN1V (ORCPT ); Wed, 9 Dec 2020 08:27:21 -0500 Received: from mail-wm1-x342.google.com (mail-wm1-x342.google.com [IPv6:2a00:1450:4864:20::342]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 94E57C0613D6 for ; Wed, 9 Dec 2020 05:26:40 -0800 (PST) Received: by mail-wm1-x342.google.com with SMTP id a3so1665328wmb.5 for ; Wed, 09 Dec 2020 05:26:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=4DYUQu0RnUP+8Pjc8kSEgv+OIMP/f6lYTVbWVeSCUVU=; b=cUVqsj5LFdc+s2n2frLO3T8S38RQsoBLeYHX17kARTFQTCge3mWtrw2y4Fax8dMg4m xzZldvYLG8rhEQg+Ix+NJOhdwlSXZM/ngCJMgA5oEuWDYfqMW5nZPKFbX9ItrjzeBmpf OHBBK6ogpwYle2XEzAhaKeA3kXmwNkwURGvWw= 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:mime-version :content-transfer-encoding; bh=4DYUQu0RnUP+8Pjc8kSEgv+OIMP/f6lYTVbWVeSCUVU=; b=NFqzTHozy8/ZXTTpkA93dg69UQyN1XuiHlmFhQxttRQMQgeG3QYJtdp1zgjZqly+2T 2fqhZxko1XmQLmmwY4fySjqApq2l71Z8MuEuQcLHghYx33cyrxTftG5TH8cTqXIBOEFm HG0rVnhQLiJ8vhhtH2Co0QaUER9XZerMcnYypf7ODyc04G4SuRHwndcaP32b1A0xJ76H /XTAVwCib4MjCd+uc/KYHa73QwvqeZRvVmNIglJS5ZvSqDBU6DCX9BTyywzElUn/6EDv uBwmbxDGZF4pAn0M8pl8XDic52JB8nzr0x5Umc6HsCxhAJ83bMTWFVb6i8Y6UTpknMTd 7onA== X-Gm-Message-State: AOAM533xX31TgT585NpKd0hy+5bRytWPk1lMlrk0oUOEKXvIby7VgR6o dSwktb+ScCIKAqUeEzXQkg1/e6dUvuIdGg== X-Google-Smtp-Source: ABdhPJwLBziMD/Ljjjw3q8OIMyTD0saGfmpzb1kCQxNpJdFatuw4VS2TS2f98pqGUZQx1/zoYy6KHw== X-Received: by 2002:a7b:c205:: with SMTP id x5mr2903826wmi.115.1607520399095; Wed, 09 Dec 2020 05:26:39 -0800 (PST) Received: from revest.zrh.corp.google.com ([2a00:79e0:42:204:f693:9fff:fef4:a569]) by smtp.gmail.com with ESMTPSA id t16sm3631490wri.42.2020.12.09.05.26.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 09 Dec 2020 05:26:38 -0800 (PST) From: Florent Revest To: bpf@vger.kernel.org Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, kpsingh@chromium.org, kafai@fb.com, linux-kernel@vger.kernel.org, Florent Revest Subject: [PATCH bpf-next v4 1/4] bpf: Be less specific about socket cookies guarantees Date: Wed, 9 Dec 2020 14:26:33 +0100 Message-Id: <20201209132636.1545761-1-revest@chromium.org> X-Mailer: git-send-email 2.29.2.576.ga3fc446d84-goog MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Since "92acdc58ab11 bpf, net: Rework cookie generator as per-cpu one" socket cookies are not guaranteed to be non-decreasing. The bpf_get_socket_cookie helper descriptions are currently specifying that cookies are non-decreasing but we don't want users to rely on that. Reported-by: Daniel Borkmann Signed-off-by: Florent Revest --- include/uapi/linux/bpf.h | 8 ++++---- tools/include/uapi/linux/bpf.h | 8 ++++---- 2 files changed, 8 insertions(+), 8 deletions(-) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 30b477a26482..ba59309f4d18 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1650,22 +1650,22 @@ union bpf_attr { * networking traffic statistics as it provides a global socket * identifier that can be assumed unique. * Return - * A 8-byte long non-decreasing number on success, or 0 if the - * socket field is missing inside *skb*. + * A 8-byte long unique number on success, or 0 if the socket + * field is missing inside *skb*. * * u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx) * Description * Equivalent to bpf_get_socket_cookie() helper that accepts * *skb*, but gets socket from **struct bpf_sock_addr** context. * Return - * A 8-byte long non-decreasing number. + * A 8-byte long unique number. * * u64 bpf_get_socket_cookie(struct bpf_sock_ops *ctx) * Description * Equivalent to **bpf_get_socket_cookie**\ () helper that accepts * *skb*, but gets socket from **struct bpf_sock_ops** context. * Return - * A 8-byte long non-decreasing number. + * A 8-byte long unique number. * * u32 bpf_get_socket_uid(struct sk_buff *skb) * Return diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 30b477a26482..ba59309f4d18 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1650,22 +1650,22 @@ union bpf_attr { * networking traffic statistics as it provides a global socket * identifier that can be assumed unique. * Return - * A 8-byte long non-decreasing number on success, or 0 if the - * socket field is missing inside *skb*. + * A 8-byte long unique number on success, or 0 if the socket + * field is missing inside *skb*. * * u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx) * Description * Equivalent to bpf_get_socket_cookie() helper that accepts * *skb*, but gets socket from **struct bpf_sock_addr** context. * Return - * A 8-byte long non-decreasing number. + * A 8-byte long unique number. * * u64 bpf_get_socket_cookie(struct bpf_sock_ops *ctx) * Description * Equivalent to **bpf_get_socket_cookie**\ () helper that accepts * *skb*, but gets socket from **struct bpf_sock_ops** context. * Return - * A 8-byte long non-decreasing number. + * A 8-byte long unique number. * * u32 bpf_get_socket_uid(struct sk_buff *skb) * Return