From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roman Gushchin Subject: [PATCH bpf] bpf: harden flags check in cgroup_storage_update_elem() Date: Fri, 28 Sep 2018 14:33:21 +0100 Message-ID: <20180928133321.31121-1-guro@fb.com> Mime-Version: 1.0 Content-Type: text/plain Cc: , , Roman Gushchin , Alexei Starovoitov , Daniel Borkmann To: Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org cgroup_storage_update_elem() shouldn't accept any flags argument values except BPF_ANY and BPF_EXIST to guarantee the backward compatibility, had a new flag value been added. Fixes: de9cbbaadba5 ("bpf: introduce cgroup storage maps") Signed-off-by: Roman Gushchin Cc: Alexei Starovoitov Cc: Daniel Borkmann --- kernel/bpf/local_storage.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c index f8746e6a9a35..2a7680106320 100644 --- a/kernel/bpf/local_storage.c +++ b/kernel/bpf/local_storage.c @@ -130,7 +130,7 @@ static int cgroup_storage_update_elem(struct bpf_map *map, void *_key, struct bpf_cgroup_storage *storage; struct bpf_storage_buffer *new; - if (flags & BPF_NOEXIST) + if (flags != BPF_ANY && flags != BPF_EXIST) return -EINVAL; storage = cgroup_storage_lookup((struct bpf_cgroup_storage_map *)map, -- 2.17.1