From patchwork Tue Apr 2 20:19:54 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Ignatov X-Patchwork-Id: 1074904 Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=fb.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=fb.com header.i=@fb.com header.b="QcYcaRES"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44YgZC6TSwz9sNt for ; Wed, 3 Apr 2019 07:20:35 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726399AbfDBUUe (ORCPT ); Tue, 2 Apr 2019 16:20:34 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:56394 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725812AbfDBUUd (ORCPT ); Tue, 2 Apr 2019 16:20:33 -0400 Received: from pps.filterd (m0109332.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x32KIfbl017277 for ; Tue, 2 Apr 2019 13:20:32 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : mime-version : content-type; s=facebook; bh=uhW+bAUjPmSrox+KQQfEo3bpGiR2thw/Ro6lQvfuc5s=; b=QcYcaRESS+OiWG/YasYfsRXwsyAuzkj7m7BsJCMoU37HnLbG14/KNLgGzh28bMhVuXOR +DEVdUnbv4NPDDTI5JNlZPx8ybykqcZ29m80unjn8EI3oFFwhROnFaNE5Omk6oSOCf3n x4nqAgWxJBQR5cvhgWIXiO6AY30t/+MjtQY= Received: from mail.thefacebook.com ([199.201.64.23]) by mx0a-00082601.pphosted.com with ESMTP id 2rmdq6g79c-3 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT) for ; Tue, 02 Apr 2019 13:20:32 -0700 Received: from mx-out.facebook.com (2620:10d:c081:10::13) by mail.thefacebook.com (2620:10d:c081:35::126) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA) id 15.1.1713.5; Tue, 2 Apr 2019 13:20:30 -0700 Received: by dev082.prn2.facebook.com (Postfix, from userid 572249) id 3A7623701A4F; Tue, 2 Apr 2019 13:20:30 -0700 (PDT) Smtp-Origin-Hostprefix: dev From: Andrey Ignatov Smtp-Origin-Hostname: dev082.prn2.facebook.com To: CC: Andrey Ignatov , , , Smtp-Origin-Cluster: prn2c23 Subject: [PATCH bpf-next 0/5] bpf: Fix indirect var_off stack access support Date: Tue, 2 Apr 2019 13:19:54 -0700 Message-ID: X-Mailer: git-send-email 2.17.1 X-FB-Internal: Safe MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-04-02_08:, , signatures=0 X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patch set is a follow-up for discussion [1]. It fixes variable offset stack access handling for raw and unprivileged mode, rejecting both of them. Patch 1 handles raw (uninitialized) mode. Patch 2 adds test for raw mode. Patch 3 handles unprivileged mode. Patch 4 adds test for unprivileged mode. Patch 5 is a minor fix in verbose log. Unprivileged mode is an interesting case since one (and only?) way to come up with variable offset is to use pointer arithmetics. Though pointer arithmetics is already prohibited for unprivileged mode. I'm not sure if it's enough though and it seems like a good idea to still reject variable offset for unpriv in check_stack_boundary(). Please see patches 3 and 4 for more details on this. [1] https://marc.info/?l=linux-netdev&m=155419526427742&w=2 Andrey Ignatov (5): bpf: Reject indirect var_off stack access in raw mode selftests/bpf: Test indirect var_off stack access in raw mode bpf: Reject indirect var_off stack access in unpriv mode selftests/bpf: Test indirect var_off stack access in unpriv mode bpf: Add missed newline in verifier verbose log kernel/bpf/verifier.c | 43 ++++++++++++--- .../testing/selftests/bpf/verifier/var_off.c | 54 +++++++++++++++++++ 2 files changed, 90 insertions(+), 7 deletions(-)