| Message ID | 20160914072415.26021-15-mic@digikod.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Sep 14, 2016 at 09:24:07AM +0200, Mickaël Salaün wrote: > This will be useful to support Landlock for the next commits. > > Signed-off-by: Mickaël Salaün <mic@digikod.net> > Cc: Alexei Starovoitov <ast@kernel.org> > Cc: Daniel Borkmann <daniel@iogearbox.net> > Cc: Daniel Mack <daniel@zonque.org> > Cc: David S. Miller <davem@davemloft.net> > Cc: Tejun Heo <tj@kernel.org> I think this is good to do regardless. Sooner or later cgroup_bpf_update will start rejecting the prog attach. Like we discussed to have a flag that would dissallow processeses lower in the cgroup hierarchy to install their own bpf programs. It will be minimal change to bpf_prog_attach() error handling, but will greatly help Mickael to build stuff on top. DanielM can you refactor your patch to do that from the start ? Thanks! > --- > 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 > -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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 */
This will be useful to support Landlock for the next commits. Signed-off-by: Mickaël Salaün <mic@digikod.net> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Daniel Mack <daniel@zonque.org> Cc: David S. Miller <davem@davemloft.net> Cc: Tejun Heo <tj@kernel.org> --- 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(-)