diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index c225c42e114a..077ed3a19848 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -16,6 +16,8 @@ #include #include +#include "../cgroup/cgroup-internal.h" + DEFINE_STATIC_KEY_FALSE(cgroup_bpf_enabled_key); EXPORT_SYMBOL(cgroup_bpf_enabled_key); @@ -38,6 +40,8 @@ static void cgroup_bpf_release(struct work_struct *work) struct bpf_prog_array *old_array; unsigned int type; + mutex_lock(&cgroup_mutex); + for (type = 0; type < ARRAY_SIZE(cgrp->bpf.progs); type++) { struct list_head *progs = &cgrp->bpf.progs[type]; struct bpf_prog_list *pl, *tmp; @@ -54,10 +58,12 @@ static void cgroup_bpf_release(struct work_struct *work) } old_array = rcu_dereference_protected( cgrp->bpf.effective[type], - percpu_ref_is_dying(&cgrp->bpf.refcnt)); + lockdep_is_held(&cgroup_mutex)); bpf_prog_array_free(old_array); } + mutex_unlock(&cgroup_mutex); + percpu_ref_exit(&cgrp->bpf.refcnt); cgroup_put(cgrp); } @@ -229,6 +235,9 @@ static int update_effective_progs(struct cgroup *cgrp, css_for_each_descendant_pre(css, &cgrp->self) { struct cgroup *desc = container_of(css, struct cgroup, self); + if (percpu_ref_is_zero(&desc->bpf.refcnt)) + continue; + err = compute_effective_progs(desc, type, &desc->bpf.inactive); if (err) goto cleanup; @@ -238,6 +247,14 @@ static int update_effective_progs(struct cgroup *cgrp, css_for_each_descendant_pre(css, &cgrp->self) { struct cgroup *desc = container_of(css, struct cgroup, self); + if (percpu_ref_is_zero(&desc->bpf.refcnt)) { + if (unlikely(desc->bpf.inactive)) { + bpf_prog_array_free(desc->bpf.inactive); + desc->bpf.inactive = NULL; + } + continue; + } + activate_effective_progs(desc, type, desc->bpf.inactive); desc->bpf.inactive = NULL; }