On Wed, May 29, 2019 at 6:05 PM Roman Gushchin <guro@xxxxxx> wrote:
>
> Cgroup local storage maps lack the memlock precharge check,
> which is performed before the memory allocation for
> most other bpf map types.
>
> Let's add it in order to unify all map types.
>
> Signed-off-by: Roman Gushchin <guro@xxxxxx>
Acked-by: Song Liu <songliubraving@xxxxxx>
> ---
> kernel/bpf/local_storage.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c
> index 980e8f1f6cb5..e48302ecb389 100644
> --- a/kernel/bpf/local_storage.c
> +++ b/kernel/bpf/local_storage.c
> @@ -272,6 +272,8 @@ static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr)
> {
> int numa_node = bpf_map_attr_numa_node(attr);
> struct bpf_cgroup_storage_map *map;
> + u32 pages;
> + int ret;
>
> if (attr->key_size != sizeof(struct bpf_cgroup_storage_key))
> return ERR_PTR(-EINVAL);
> @@ -290,13 +292,18 @@ static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr)
> /* max_entries is not used and enforced to be 0 */
> return ERR_PTR(-EINVAL);
>
> + pages = round_up(sizeof(struct bpf_cgroup_storage_map), PAGE_SIZE) >>
> + PAGE_SHIFT;
> + ret = bpf_map_precharge_memlock(pages);
> + if (ret < 0)
> + return ERR_PTR(ret);
> +
> map = kmalloc_node(sizeof(struct bpf_cgroup_storage_map),
> __GFP_ZERO | GFP_USER, numa_node);
> if (!map)
> return ERR_PTR(-ENOMEM);
>
> - map->map.pages = round_up(sizeof(struct bpf_cgroup_storage_map),
> - PAGE_SIZE) >> PAGE_SHIFT;
> + map->map.pages = pages;
>
> /* copy mandatory map attributes */
> bpf_map_init_from_attr(&map->map, attr);
> --
> 2.20.1
>
