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=-2.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 0C95FC433DB for ; Tue, 30 Mar 2021 23:17:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C29B6619D3 for ; Tue, 30 Mar 2021 23:17:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233302AbhC3XRC (ORCPT ); Tue, 30 Mar 2021 19:17:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46748 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233286AbhC3XQ5 (ORCPT ); Tue, 30 Mar 2021 19:16:57 -0400 Received: from mail-lj1-x230.google.com (mail-lj1-x230.google.com [IPv6:2a00:1450:4864:20::230]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C47AC061574; Tue, 30 Mar 2021 16:16:57 -0700 (PDT) Received: by mail-lj1-x230.google.com with SMTP id r20so21700998ljk.4; Tue, 30 Mar 2021 16:16:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=EWsgIY/KITNt+W2mkHu5D1R/oQVu42eT5oqQDwOADXc=; b=tBSG5Wgi9/tBMW9beWfY+aRlBjJplJr7iUTD5jTJMnfJEj7kGyHp9amEnNyujCAbRr vLmvAVyt23FvuHZvZbtv8O+ND0wE1MT4EDZrRHg+bOjAToRFkX9pQRjmotQUCm8wmpB7 wtUiJIS542ias7HYx38wHPJ7cgp7rP40SD3rpAKN4Hle6IgykMHf0OKU9RqdqwLQHbyJ wBW1dDoQ/qpbUe6YV/lY7fv+5ANQ2FrH824WzSoOn1MyxnNvEBVtYPgCTKsJzOkdDNKb 8Z+wz9QeGwrKR145Fs2H0eANh+uFERMXydsGg4n0rP19AuvXWci3QgE+K43ByiukVri2 w1sQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=EWsgIY/KITNt+W2mkHu5D1R/oQVu42eT5oqQDwOADXc=; b=eh0Lknn/FfSGRbGaRmooMOXwIAZVb6khEdDoXHwX/FsnKOT5OrayzhquG1tsZy2uot o8nKYd9hHFLWbsZrVecWBDJRy3Zn4BapY4LYqtY2ob5ONfWTxDo8T1NlBHO953u3/Zx8 Rd4Ysa5kkCyUt3IBLpPFGyF9YmxpdZsZMsIphxwn7+uS0fd2a60PdwIU3t//tQPOn/nn 2mDdQPTlCndWT1MD90gLuHKBuISqDJSoqIqFmPWFSEAl3tVDgEmwNlHo7VP9+ozSjOtF 5HMvAvOpZtJboy5gvoJbEVnR5k03CPv+Na9S8xzhIF0kO7AzV1ry751JEw0wdjFoToMV IjHA== X-Gm-Message-State: AOAM5339mBCp6Dqjkh3jHV5ku2VTsfvaIroKovxhSXO4tNuMYK3duo6E 6KDFrwBTMyKYmMAB5eh7Q4h4bQG35mbuYdBxWrk= X-Google-Smtp-Source: ABdhPJwR/ZiW/Ib8se1El1ywPeNU/uY0j6KlzbDaUWk8s1HXzKWJg38nH35PepRkwR6tApzoIOlUOKH5CD9Zp4fTyls= X-Received: by 2002:a2e:900b:: with SMTP id h11mr259742ljg.258.1617146215959; Tue, 30 Mar 2021 16:16:55 -0700 (PDT) MIME-Version: 1.0 References: <20210330223748.399563-1-pctammela@mojatatu.com> In-Reply-To: <20210330223748.399563-1-pctammela@mojatatu.com> From: Alexei Starovoitov Date: Tue, 30 Mar 2021 16:16:44 -0700 Message-ID: Subject: Re: [PATCH bpf-next v2] bpf: check flags in 'bpf_ringbuf_discard()' and 'bpf_ringbuf_submit()' To: Pedro Tammela Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Joe Stringer , Quentin Monnet , "open list:BPF (Safe dynamic programs and tools)" , "open list:BPF (Safe dynamic programs and tools)" , open list , Pedro Tammela Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, Mar 30, 2021 at 3:54 PM Pedro Tammela wrote: > > BPF_CALL_2(bpf_ringbuf_submit, void *, sample, u64, flags) > { > + if (unlikely(flags & ~(BPF_RB_NO_WAKEUP | BPF_RB_FORCE_WAKEUP))) > + return -EINVAL; > + > bpf_ringbuf_commit(sample, flags, false /* discard */); > + > return 0; I think ringbuf design was meant for bpf_ringbuf_submit to never fail. If we do flag validation it probably should be done at the verifier time.