@@ -69,9 +69,13 @@ struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd)
/* Misc members not needed in bpf_map_meta_equal() check. */
inner_map_meta->ops = inner_map->ops;
if (inner_map->ops == &array_map_ops) {
+ struct bpf_array *inner_array_meta =
+ container_of(inner_map_meta, struct bpf_array, map);
+ struct bpf_array *inner_array = container_of(inner_map, struct bpf_array, map);
+
+ inner_array_meta->index_mask = inner_array->index_mask;
+ inner_array_meta->elem_size = inner_array->elem_size;
inner_map_meta->bypass_spec_v1 = inner_map->bypass_spec_v1;
- container_of(inner_map_meta, struct bpf_array, map)->index_mask =
- container_of(inner_map, struct bpf_array, map)->index_mask;
}
fdput(f);
Commit d937bc3449fa ("bpf: make uniform use of array->elem_size everywhere in arraymap.c") changed array_map_gen_lookup to use array->elem_size instead of round_up(map->value_size, 8) as the element size when generating code to access a value in an array map. array->elem_size, however, is not set by bpf_map_meta_alloc when initializing an BPF_MAP_TYPE_ARRAY_OF_MAPS or BPF_MAP_TYPE_HASH_OF_MAPS. This results in array_map_gen_lookup incorrectly outputting code that always accesses index 0 in the array (as the index will be calculated via a multiplication with the element size, which is incorrectly set to 0). Set elem_size on the bpf_array object when allocating an array or hash of maps to fix this. Fixes: d937bc3449fa ("bpf: make uniform use of array->elem_size everywhere in arraymap.c") Signed-off-by: Rhys Rustad-Elliott <me@rhysre.net> --- kernel/bpf/map_in_map.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)