From patchwork Mon Mar 23 16:44:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: KP Singh X-Patchwork-Id: 11453497 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A6B8A17D4 for ; Mon, 23 Mar 2020 16:44:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 841F42072D for ; Mon, 23 Mar 2020 16:44:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="eqUEy4dB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727725AbgCWQoi (ORCPT ); Mon, 23 Mar 2020 12:44:38 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:33466 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727590AbgCWQoi (ORCPT ); Mon, 23 Mar 2020 12:44:38 -0400 Received: by mail-wr1-f65.google.com with SMTP id a25so17987971wrd.0 for ; Mon, 23 Mar 2020 09:44:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=zSkW27zNSTC4Fc8TCI5UW+0DrKRV7Bu83mzAYD1k77Q=; b=eqUEy4dBM9mRAZt0PUr5927OFcXnR7WrVJyYuAyLEwz7/Oz+EeSXeU03igSPYZE5pj zco57O5wqYcErl/jIG/o8G3dmrPl+Xz2M+dKj0Kwx3IjrzQrax9uPqGbywBsiv7h09Gt Uu7uHZRasHOIfhuzXsfyCtXoB5fy5t2e/dp58= 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=zSkW27zNSTC4Fc8TCI5UW+0DrKRV7Bu83mzAYD1k77Q=; b=c4+95csG/A2dwpYUqGmvf2nKWGymJ7SyfovqBGah/HNDLS9fyQyEQgMCIx0mO75Q2T Wp3peF0kEzfDyTxoMT9ge5cBvL6DNlZL6+H8wRwhKoUgcdoRhqXBJo1g3/OSbGqZJJJR sQd37COxCsp2cwdykn4ntLidXhBQRP6csdhwHGCe4fdZDoEh2/hoEVzILHvO665LyuFk 2e71o7d4sazCgFnTyrpJRG5mnDHIUAAeVEQle+fa6Xz+G7AulBiGW1sXEwOsk3OD9ilt UoBE8otWeB5duywaIYOqfjqvrXsxS1XueDSFweXKSolc5nKiMhi9IDYtJUUWSykTTZQB DrfQ== X-Gm-Message-State: ANhLgQ1fbWf6Da0gBgjdmlvpxKYES2TsDCsAmVd7Dmo7Rp+xnE+bflwL Y/T2TPdczt/RRxRHeDqj2PluwQ== X-Google-Smtp-Source: ADFU+vuaOEVixoBFIafSkJToy3DhcTsnaZY/ka6brQHMO25rWVX1mKJKlzZLribRBVB0JfJ8a5Rpgw== X-Received: by 2002:adf:db41:: with SMTP id f1mr32595515wrj.247.1584981874952; Mon, 23 Mar 2020 09:44:34 -0700 (PDT) Received: from kpsingh-kernel.localdomain (77-56-209-237.dclient.hispeed.ch. [77.56.209.237]) by smtp.gmail.com with ESMTPSA id l8sm199874wmj.2.2020.03.23.09.44.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Mar 2020 09:44:34 -0700 (PDT) From: KP Singh To: linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-security-module@vger.kernel.org Cc: Brendan Jackman , Florent Revest , Alexei Starovoitov , Daniel Borkmann , James Morris , Kees Cook , Paul Turner , Jann Horn , Florent Revest , Brendan Jackman , Greg Kroah-Hartman Subject: [PATCH bpf-next v5 5/7] bpf: lsm: Initialize the BPF LSM hooks Date: Mon, 23 Mar 2020 17:44:13 +0100 Message-Id: <20200323164415.12943-6-kpsingh@chromium.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200323164415.12943-1-kpsingh@chromium.org> References: <20200323164415.12943-1-kpsingh@chromium.org> MIME-Version: 1.0 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: From: KP Singh The bpf_lsm_ nops are initialized into the LSM framework like any other LSM. Some LSM hooks do not have 0 as their default return value. The __weak symbol for these hooks is overridden by a corresponding definition in security/bpf/hooks.c The LSM can be enabled / disabled with CONFIG_LSM. Signed-off-by: KP Singh Reviewed-by: Brendan Jackman Reviewed-by: Florent Revest --- security/Kconfig | 10 ++++---- security/Makefile | 2 ++ security/bpf/Makefile | 5 ++++ security/bpf/hooks.c | 55 +++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 67 insertions(+), 5 deletions(-) create mode 100644 security/bpf/Makefile create mode 100644 security/bpf/hooks.c diff --git a/security/Kconfig b/security/Kconfig index 2a1a2d396228..cd3cc7da3a55 100644 --- a/security/Kconfig +++ b/security/Kconfig @@ -277,11 +277,11 @@ endchoice config LSM string "Ordered list of enabled LSMs" - default "lockdown,yama,loadpin,safesetid,integrity,smack,selinux,tomoyo,apparmor" if DEFAULT_SECURITY_SMACK - default "lockdown,yama,loadpin,safesetid,integrity,apparmor,selinux,smack,tomoyo" if DEFAULT_SECURITY_APPARMOR - default "lockdown,yama,loadpin,safesetid,integrity,tomoyo" if DEFAULT_SECURITY_TOMOYO - default "lockdown,yama,loadpin,safesetid,integrity" if DEFAULT_SECURITY_DAC - default "lockdown,yama,loadpin,safesetid,integrity,selinux,smack,tomoyo,apparmor" + default "lockdown,yama,loadpin,safesetid,integrity,smack,selinux,tomoyo,apparmor,bpf" if DEFAULT_SECURITY_SMACK + default "lockdown,yama,loadpin,safesetid,integrity,apparmor,selinux,smack,tomoyo,bpf" if DEFAULT_SECURITY_APPARMOR + default "lockdown,yama,loadpin,safesetid,integrity,tomoyo,bpf" if DEFAULT_SECURITY_TOMOYO + default "lockdown,yama,loadpin,safesetid,integrity,bpf" if DEFAULT_SECURITY_DAC + default "lockdown,yama,loadpin,safesetid,integrity,selinux,smack,tomoyo,apparmor,bpf" help A comma-separated list of LSMs, in initialization order. Any LSMs left off this list will be ignored. This can be diff --git a/security/Makefile b/security/Makefile index 746438499029..22e73a3482bd 100644 --- a/security/Makefile +++ b/security/Makefile @@ -12,6 +12,7 @@ subdir-$(CONFIG_SECURITY_YAMA) += yama subdir-$(CONFIG_SECURITY_LOADPIN) += loadpin subdir-$(CONFIG_SECURITY_SAFESETID) += safesetid subdir-$(CONFIG_SECURITY_LOCKDOWN_LSM) += lockdown +subdir-$(CONFIG_BPF_LSM) += bpf # always enable default capabilities obj-y += commoncap.o @@ -30,6 +31,7 @@ obj-$(CONFIG_SECURITY_LOADPIN) += loadpin/ obj-$(CONFIG_SECURITY_SAFESETID) += safesetid/ obj-$(CONFIG_SECURITY_LOCKDOWN_LSM) += lockdown/ obj-$(CONFIG_CGROUP_DEVICE) += device_cgroup.o +obj-$(CONFIG_BPF_LSM) += bpf/ # Object integrity file lists subdir-$(CONFIG_INTEGRITY) += integrity diff --git a/security/bpf/Makefile b/security/bpf/Makefile new file mode 100644 index 000000000000..c7a89a962084 --- /dev/null +++ b/security/bpf/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Copyright (C) 2020 Google LLC. + +obj-$(CONFIG_BPF_LSM) := hooks.o diff --git a/security/bpf/hooks.c b/security/bpf/hooks.c new file mode 100644 index 000000000000..68e5824868f9 --- /dev/null +++ b/security/bpf/hooks.c @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Copyright (C) 2020 Google LLC. + */ +#include +#include + +/* Some LSM hooks do not have 0 as their default return values. Override the + * __weak definitons generated by default for these hooks + */ +noinline int bpf_lsm_inode_getsecurity(struct inode *inode, const char *name, + void **buffer, bool alloc) +{ + return -EOPNOTSUPP; +} + +noinline int bpf_lsm_inode_setsecurity(struct inode *inode, const char *name, + const void *value, size_t size, + int flags) +{ + return -EOPNOTSUPP; +} + +noinline int bpf_lsm_task_prctl(int option, unsigned long arg2, + unsigned long arg3, unsigned long arg4, + unsigned long arg5) +{ + return -ENOSYS; +} + +noinline int bpf_lsm_xfrm_state_pol_flow_match(struct xfrm_state *x, + struct xfrm_policy *xp, + const struct flowi *fl) +{ + return 1; +} + +static struct security_hook_list bpf_lsm_hooks[] __lsm_ro_after_init = { + #define LSM_HOOK(RET, NAME, ...) LSM_HOOK_INIT(NAME, bpf_lsm_##NAME), + #include + #undef LSM_HOOK +}; + +static int __init bpf_lsm_init(void) +{ + security_add_hooks(bpf_lsm_hooks, ARRAY_SIZE(bpf_lsm_hooks), "bpf"); + pr_info("LSM support for eBPF active\n"); + return 0; +} + +DEFINE_LSM(bpf) = { + .name = "bpf", + .init = bpf_lsm_init, +};