Commit 4288ea00 authored Sep 28, 2018 by Roman Gushchin Committed by Daniel Borkmann Sep 28, 2018

bpf: harden flags check in cgroup_storage_update_elem()



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: de9cbbaa ("bpf: introduce cgroup storage maps")
Signed-off-by: Roman Gushchin <guro@fb.com>
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

parent d4ce5808

kernel/bpf/local_storage.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -129,7 +129,7 @@ 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,