From patchwork Wed Oct 26 06:56:50 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Micka=C3=ABl_Sala=C3=BCn?= X-Patchwork-Id: 9396069 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id B546160236 for ; Wed, 26 Oct 2016 07:01:18 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7EB2529885 for ; Wed, 26 Oct 2016 07:01:18 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 732FB2988D; Wed, 26 Oct 2016 07:01:18 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id 5006E29885 for ; Wed, 26 Oct 2016 07:01:14 +0000 (UTC) Received: (qmail 11671 invoked by uid 550); 26 Oct 2016 06:58:22 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Reply-To: kernel-hardening@lists.openwall.com Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 11415 invoked from network); 26 Oct 2016 06:58:15 -0000 From: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= To: linux-kernel@vger.kernel.org Cc: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= , Alexei Starovoitov , Andy Lutomirski , Daniel Borkmann , Daniel Mack , David Drysdale , "David S . Miller" , "Eric W . Biederman" , James Morris , Jann Horn , Kees Cook , Paul Moore , Sargun Dhillon , "Serge E . Hallyn" , Tejun Heo , Thomas Graf , Will Drewry , kernel-hardening@lists.openwall.com, linux-api@vger.kernel.org, linux-security-module@vger.kernel.org, netdev@vger.kernel.org, cgroups@vger.kernel.org Date: Wed, 26 Oct 2016 08:56:50 +0200 Message-Id: <20161026065654.19166-15-mic@digikod.net> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20161026065654.19166-1-mic@digikod.net> References: <20161026065654.19166-1-mic@digikod.net> MIME-Version: 1.0 X-Antivirus: Dr.Web (R) for Unix mail servers drweb plugin ver.6.0.2.8 X-Antivirus-Code: 0x100000 Subject: [kernel-hardening] [RFC v4 14/18] bpf/cgroup: Make cgroup_bpf_update() return an error code X-Virus-Scanned: ClamAV using ClamSMTP This will be useful to support Landlock for the next commits. Signed-off-by: Mickaël Salaün Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Daniel Mack Cc: David S. Miller Cc: Tejun Heo --- include/linux/bpf-cgroup.h | 4 ++-- kernel/bpf/cgroup.c | 3 ++- kernel/bpf/syscall.c | 10 ++++++---- kernel/cgroup.c | 6 ++++-- 4 files changed, 14 insertions(+), 9 deletions(-) diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h index 2f608e5d94e9..aab1aa91c064 100644 --- a/include/linux/bpf-cgroup.h +++ b/include/linux/bpf-cgroup.h @@ -31,13 +31,13 @@ struct cgroup_bpf { void cgroup_bpf_put(struct cgroup *cgrp); void cgroup_bpf_inherit(struct cgroup *cgrp, struct cgroup *parent); -void __cgroup_bpf_update(struct cgroup *cgrp, +int __cgroup_bpf_update(struct cgroup *cgrp, struct cgroup *parent, struct bpf_prog *prog, enum bpf_attach_type type); /* Wrapper for __cgroup_bpf_update() protected by cgroup_mutex */ -void cgroup_bpf_update(struct cgroup *cgrp, +int cgroup_bpf_update(struct cgroup *cgrp, struct bpf_prog *prog, enum bpf_attach_type type); diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 75482cd92d56..269b410d890c 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -83,7 +83,7 @@ void cgroup_bpf_inherit(struct cgroup *cgrp, struct cgroup *parent) * * Must be called with cgroup_mutex held. */ -void __cgroup_bpf_update(struct cgroup *cgrp, +int __cgroup_bpf_update(struct cgroup *cgrp, struct cgroup *parent, struct bpf_prog *prog, enum bpf_attach_type type) @@ -116,6 +116,7 @@ void __cgroup_bpf_update(struct cgroup *cgrp, bpf_prog_put(old_prog); static_branch_dec(&cgroup_bpf_enabled_key); } + return 0; } /** diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index ac4cbb98596d..e62123aeb202 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -831,6 +831,7 @@ static int bpf_prog_attach(const union bpf_attr *attr) { struct bpf_prog *prog; struct cgroup *cgrp; + int result; if (!capable(CAP_NET_ADMIN)) return -EPERM; @@ -858,10 +859,10 @@ static int bpf_prog_attach(const union bpf_attr *attr) return PTR_ERR(cgrp); } - cgroup_bpf_update(cgrp, prog, attr->attach_type); + result = cgroup_bpf_update(cgrp, prog, attr->attach_type); cgroup_put(cgrp); - return 0; + return result; } #define BPF_PROG_DETACH_LAST_FIELD attach_type @@ -869,6 +870,7 @@ static int bpf_prog_attach(const union bpf_attr *attr) static int bpf_prog_detach(const union bpf_attr *attr) { struct cgroup *cgrp; + int result = 0; if (!capable(CAP_NET_ADMIN)) return -EPERM; @@ -883,7 +885,7 @@ static int bpf_prog_detach(const union bpf_attr *attr) if (IS_ERR(cgrp)) return PTR_ERR(cgrp); - cgroup_bpf_update(cgrp, NULL, attr->attach_type); + result = cgroup_bpf_update(cgrp, NULL, attr->attach_type); cgroup_put(cgrp); break; @@ -891,7 +893,7 @@ static int bpf_prog_detach(const union bpf_attr *attr) return -EINVAL; } - return 0; + return result; } #endif /* CONFIG_CGROUP_BPF */ diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 2ee9ec3051b2..f77a974eb960 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -6501,15 +6501,17 @@ static __init int cgroup_namespaces_init(void) subsys_initcall(cgroup_namespaces_init); #ifdef CONFIG_CGROUP_BPF -void cgroup_bpf_update(struct cgroup *cgrp, +int cgroup_bpf_update(struct cgroup *cgrp, struct bpf_prog *prog, enum bpf_attach_type type) { struct cgroup *parent = cgroup_parent(cgrp); + int result; mutex_lock(&cgroup_mutex); - __cgroup_bpf_update(cgrp, parent, prog, type); + result = __cgroup_bpf_update(cgrp, parent, prog, type); mutex_unlock(&cgroup_mutex); + return result; } #endif /* CONFIG_CGROUP_BPF */