From: Andrii Nakryiko andriin@fb.com
commit 1d8006abaab4cb90f81add86e8d1bf9411add05a upstream.
There is no compensating cgroup_bpf_put() for each ancestor cgroup in cgroup_bpf_inherit(). If compute_effective_progs returns error, those cgroups won't be freed ever. Fix it by putting them in cleanup code path.
Fixes: e10360f815ca ("bpf: cgroup: prevent out-of-order release of cgroup bpf") Signed-off-by: Andrii Nakryiko andriin@fb.com Signed-off-by: Alexei Starovoitov ast@kernel.org Acked-by: Roman Gushchin guro@fb.com Link: https://lore.kernel.org/bpf/20200309224017.1063297-1-andriin@fb.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- kernel/bpf/cgroup.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -228,6 +228,9 @@ cleanup: for (i = 0; i < NR; i++) bpf_prog_array_free(arrays[i]);
+ for (p = cgroup_parent(cgrp); p; p = cgroup_parent(p)) + cgroup_bpf_put(p); + percpu_ref_exit(&cgrp->bpf.refcnt);
return -ENOMEM;