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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 855EFC77B75 for ; Wed, 3 May 2023 18:28:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229574AbjECS2w (ORCPT ); Wed, 3 May 2023 14:28:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60870 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229502AbjECS2v (ORCPT ); Wed, 3 May 2023 14:28:51 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 503352680 for ; Wed, 3 May 2023 11:28:50 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id 3f1490d57ef6-b9a7766d1f2so6711049276.3 for ; Wed, 03 May 2023 11:28:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1683138529; x=1685730529; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=EZ/jGuqYbI8If8gOnXaeKTa2gI+Xs7Sbz/cjlu7FfLw=; b=27VimN5M6KTdi+VlALws3NLGjjODWrvWzKyvn61EOf1GwirSbPz05RBpIS2FmqO54p dm3Snoj3kb8mJJfDd8ukVudt+MtJvixRCqNpvNzo7MF8H4yMS0PW7wKuW0M15+5sVgJ2 HCeRI28uC2b4uk9BR6segWUtTXd01VgzNT1HtBlLnMTHedYf4uBXY6TxfcOdcZFlEXj9 vPrMTJQBboj74bBmIdA/YcRIgOEg717AXm1c8j5X+w1b8ufV8/SfiiJWfaZCO8rYssU7 jAYQU12opZTxsOgz2rCXt0J0ocFyHTCMEcz9pI5ZIqiSeIFD0tWG7w8hTB+sudtiVfsV dApA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683138529; x=1685730529; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=EZ/jGuqYbI8If8gOnXaeKTa2gI+Xs7Sbz/cjlu7FfLw=; b=QMVE81EhcUAgbJlclasA3dGNl0fIVzyN12MQ561RCCz9MekXuO+eA+G+pVGagf1L7s X/S3aSnK3eabiYcbBrawDfrbB9izrRoiVVLttIcRwD7oYiWb6SmiHKxLzLU5YFfixlNn 9hHLevJOudSoyXAiR7ZyXEV5e/aXwjVRg2T4LrttsD2dlIE5/0uHtCoon5NVOwF9iOlN 5qcmJg/znAkUSB6bPeGal6Waa1+Cse1apydYJ6bhiaUvfBbXqMTdUTsaTb5gKn1W+L/r HFbkYsJ6ymW3+YE8KSS59SecOBuh47C741lVNNQ7GG+pxv9JVY095HLVc7OuyN4Clxyw xicw== X-Gm-Message-State: AC+VfDy6hCovLPeV0T54jyVFUDZEUz946OOGDf7cAHAUn92Q8URlUjmH zJfT6nDdb9wZ+dn6rf/9oQg32co= X-Google-Smtp-Source: ACHHUZ4Ns2eyWtzTY9XWeLEDabhawS/PJDJT8iiFHxPn1KSJPIByi6lGLXZmO7E/LMIYEi048fDV1Xg= X-Received: from sdf.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5935]) (user=sdf job=sendgmr) by 2002:a25:2d27:0:b0:b9a:696a:770f with SMTP id t39-20020a252d27000000b00b9a696a770fmr13699499ybt.13.1683138529588; Wed, 03 May 2023 11:28:49 -0700 (PDT) Date: Wed, 3 May 2023 11:28:48 -0700 In-Reply-To: <20230502230619.2592406-2-andrii@kernel.org> Mime-Version: 1.0 References: <20230502230619.2592406-1-andrii@kernel.org> <20230502230619.2592406-2-andrii@kernel.org> Message-ID: Subject: Re: [PATCH bpf-next 01/10] bpf: move unprivileged checks into map_create() and bpf_prog_load() From: Stanislav Fomichev To: Andrii Nakryiko Cc: bpf@vger.kernel.org, ast@kernel.org, daniel@iogearbox.net, martin.lau@kernel.org, kernel-team@meta.com Content-Type: text/plain; charset="utf-8" Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On 05/02, Andrii Nakryiko wrote: > Make each bpf() syscall command a bit more self-contained, making it > easier to further enhance it. We move sysctl_unprivileged_bpf_disabled > handling down to map_create() and bpf_prog_load(), two special commands > in this regard. > > Also swap the order of checks, calling bpf_capable() only if > sysctl_unprivileged_bpf_disabled is true, avoiding unnecessary audit > messages. > > Signed-off-by: Andrii Nakryiko > --- > kernel/bpf/syscall.c | 37 ++++++++++++++++++++++--------------- > 1 file changed, 22 insertions(+), 15 deletions(-) > > diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c > index 14f39c1e573e..d5009fafe0f4 100644 > --- a/kernel/bpf/syscall.c > +++ b/kernel/bpf/syscall.c > @@ -1132,6 +1132,17 @@ static int map_create(union bpf_attr *attr) > int f_flags; > int err; [..] > + /* Intent here is for unprivileged_bpf_disabled to block key object > + * creation commands for unprivileged users; other actions depend > + * of fd availability and access to bpffs, so are dependent on > + * object creation success. Capabilities are later verified for > + * operations such as load and map create, so even with unprivileged > + * BPF disabled, capability checks are still carried out for these > + * and other operations. > + */ > + if (sysctl_unprivileged_bpf_disabled && !bpf_capable()) > + return -EPERM; > + Does it make sense to have something like unpriv_bpf_capable() to avoid the copy-paste?