From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= Subject: [RFC v3 14/22] bpf/cgroup: Make cgroup_bpf_update() return an error code Date: Wed, 14 Sep 2016 09:24:07 +0200 Message-ID: <20160914072415.26021-15-mic@digikod.net> References: <20160914072415.26021-1-mic@digikod.net> Reply-To: kernel-hardening@lists.openwall.com Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Return-path: List-Post: List-Help: List-Unsubscribe: List-Subscribe: In-Reply-To: <20160914072415.26021-1-mic@digikod.net> To: linux-kernel@vger.kernel.org Cc: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= , Alexei Starovoitov , Andy Lutomirski , Arnd Bergmann , Casey Schaufler , Daniel Borkmann , Daniel Mack , David Drysdale , "David S . Miller" , Elena Reshetova , "Eric W . Biederman" , James Morris , Kees Cook , Paul Moore , Sargun Dhillon , "Serge E . Hallyn" , Tejun Heo , Will Drewry , kernel-hardening@lists.openwall.com, linux-api@vger.kernel.org, linux-security-module@vger. List-Id: linux-api@vger.kernel.org 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 2234042d7f61..6cca7924ee17 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 782878ec4f2d..7b75fa692617 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) @@ -117,6 +117,7 @@ void __cgroup_bpf_update(struct cgroup *cgrp, bpf_prog_put(old_pinned.prog); static_branch_dec(&cgroup_bpf_enabled_key); } + return 0; } /** diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 45a91d511119..c978f2d9a1b3 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 87324ce481b1..48b650a640a9 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -6450,15 +6450,17 @@ 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 */ -- 2.9.3