diff options
Diffstat (limited to 'kernel/bpf/map_in_map.c')
| -rw-r--r-- | kernel/bpf/map_in_map.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/kernel/bpf/map_in_map.c b/kernel/bpf/map_in_map.c index d2cbab4bdf64..0fa3f2ac0f99 100644 --- a/kernel/bpf/map_in_map.c +++ b/kernel/bpf/map_in_map.c @@ -25,6 +25,10 @@ struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd) if (!inner_map->ops->map_meta_equal) return ERR_PTR(-ENOTSUPP); + /* An inner map has no used_maps reference to hold it under a queued callback. */ + if (btf_record_has_field(inner_map->record, BPF_RCU_HEAD)) + return ERR_PTR(-EOPNOTSUPP); + inner_map_meta_size = sizeof(*inner_map_meta); /* In some cases verifier needs to access beyond just base map. */ if (inner_map->ops == &array_map_ops || inner_map->ops == &percpu_array_map_ops) @@ -106,10 +110,13 @@ void *bpf_map_fd_get_ptr(struct bpf_map *map, return ERR_PTR(-ENOTSUPP); inner_map_meta = map->inner_map_meta; - if (inner_map_meta->ops->map_meta_equal(inner_map_meta, inner_map)) + if (inner_map_meta->ops->map_meta_equal(inner_map_meta, inner_map)) { bpf_map_inc(inner_map); - else + /* Its users are those of the outer maps from now on */ + WRITE_ONCE(inner_map->was_inner_map, true); + } else { inner_map = ERR_PTR(-EINVAL); + } return inner_map; } |