bpf: Do not allow map_freeze in struct_ops map

struct_ops map cannot support map_freeze.  Otherwise, a struct_ops
cannot be unregistered from the subsystem.

Fixes: 85d33df357 ("bpf: Introduce BPF_MAP_TYPE_STRUCT_OPS")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200305013454.535397-1-kafai@fb.com
This commit is contained in:
Martin KaFai Lau 2020-03-04 17:34:54 -08:00 committed by Alexei Starovoitov
parent 8e5290e710
commit 849b4d9458

View File

@ -1510,6 +1510,11 @@ static int map_freeze(const union bpf_attr *attr)
if (IS_ERR(map))
return PTR_ERR(map);
if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
fdput(f);
return -ENOTSUPP;
}
mutex_lock(&map->freeze_mutex);
if (map->writecnt) {