From patchwork Thu Sep 10 12:56:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenz Bauer X-Patchwork-Id: 1361556 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=reject dis=none) header.from=cloudflare.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=cloudflare.com header.i=@cloudflare.com header.a=rsa-sha256 header.s=google header.b=q67DdXRU; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4BnJyF4nswz9sTd for ; Thu, 10 Sep 2020 23:04:53 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730203AbgIJNEu (ORCPT ); Thu, 10 Sep 2020 09:04:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41836 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730859AbgIJM7o (ORCPT ); Thu, 10 Sep 2020 08:59:44 -0400 Received: from mail-wr1-x442.google.com (mail-wr1-x442.google.com [IPv6:2a00:1450:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2F8A2C06179A for ; Thu, 10 Sep 2020 05:57:32 -0700 (PDT) Received: by mail-wr1-x442.google.com with SMTP id a17so6593426wrn.6 for ; Thu, 10 Sep 2020 05:57:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cloudflare.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=DtvnCyDwB1lVP2vStSoy+HHWl1PndciwI2/ThH4w12I=; b=q67DdXRUPM1GjQDapEXoRDXdv5hZ+amW+US5cr1BCK9tGcjjskT3ZxdxxrzIp1mQvw GfGM8gge+oUevFu2ylKdM1D6rs0GQk86Zghb9C9ow3GqDXM4HQ+VT6WkpxNlQebMmedW f4hKvgFlxp2Wg9BviVeGvuCIjV0lEwdk4GlhA= 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=DtvnCyDwB1lVP2vStSoy+HHWl1PndciwI2/ThH4w12I=; b=D3IOVWPK4uI+yBLp2jtc71aHtLEulDaUzIPx1llhgZS3d+3ArWzY24vSFN4S6O4FUg ppg8xJhyBK04jrKmJSaDfqqdkP46IHJ3d1AgGFxKi4U3Mk54U/AoHwHxBBii7NnjN265 rcBWusZR/TnaNEquY7t7KodaNBob4GCSRGhcziuaUdYCE6plRZ5SfCA5KrGeh7AdJkei gYcpjPB23aPKhlxPTYhXqnfgkjLtn1FBtBKrDmrMcswOrJ4L9AYVVEi6pUSsz9er6dt9 Q1r9v2ud1GnUg3C+r6tGSdKT5gkeJMzU3cqRAuody3pUjH0Zw32Gbv95UofTsyGhg6EL ARzw== X-Gm-Message-State: AOAM530MS8vAjgkMhRRoYaVImo2zp+4uh4l1ROTEbdupl1spGfRg2BXu O5ln9zWtF9mBxm57MyPJdPkNoFC7gqyN4Q== X-Google-Smtp-Source: ABdhPJxm49Zb2Ubd32h4AwythwrOW/KDOP5McHI2/s1XdolBJoaiyXg67tdcnPgZiIqr/hhAlDHGTQ== X-Received: by 2002:adf:e481:: with SMTP id i1mr8750630wrm.391.1599742650823; Thu, 10 Sep 2020 05:57:30 -0700 (PDT) Received: from antares.lan (6.9.9.0.0.d.a.3.9.b.d.2.8.1.d.7.f.f.6.2.a.5.a.7.0.b.8.0.1.0.0.2.ip6.arpa. [2001:8b0:7a5a:26ff:7d18:2db9:3ad0:996]) by smtp.gmail.com with ESMTPSA id v6sm8737400wrt.90.2020.09.10.05.57.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Sep 2020 05:57:30 -0700 (PDT) From: Lorenz Bauer To: ast@kernel.org, yhs@fb.com, daniel@iogearbox.net, kafai@fb.com, andriin@fb.com Cc: bpf@vger.kernel.org, kernel-team@cloudflare.com, Lorenz Bauer Subject: [PATCH bpf-next v3 07/11] bpf: make context access check generic Date: Thu, 10 Sep 2020 13:56:27 +0100 Message-Id: <20200910125631.225188-8-lmb@cloudflare.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200910125631.225188-1-lmb@cloudflare.com> References: <20200910125631.225188-1-lmb@cloudflare.com> MIME-Version: 1.0 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Always check context access if the register we're operating on is PTR_TO_CTX, rather than relying on ARG_PTR_TO_CTX. This allows simplifying the arg_type checking section of the function. Signed-off-by: Lorenz Bauer Acked-by: Martin KaFai Lau --- kernel/bpf/verifier.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index dc68690fb5f4..b11f1ec31078 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3974,9 +3974,6 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg, arg_type == ARG_PTR_TO_CTX_OR_NULL)) { if (type != expected_type) goto err_type; - err = check_ctx_reg(env, reg, regno); - if (err < 0) - return err; } } else if (arg_type == ARG_PTR_TO_SOCK_COMMON) { expected_type = PTR_TO_SOCK_COMMON; @@ -4060,6 +4057,10 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg, regno); return -EACCES; } + } else if (type == PTR_TO_CTX) { + err = check_ctx_reg(env, reg, regno); + if (err < 0) + return err; } if (reg->ref_obj_id) {