On Wed, May 29, 2019 at 6:05 PM Roman Gushchin <guro@xxxxxx> wrote:
>
> Socket 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>
> ---
> net/core/bpf_sk_storage.c | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c
> index cc9597a87770..9a8aaf8e235d 100644
> --- a/net/core/bpf_sk_storage.c
> +++ b/net/core/bpf_sk_storage.c
> @@ -626,7 +626,9 @@ static struct bpf_map *bpf_sk_storage_map_alloc(union bpf_attr *attr)
> struct bpf_sk_storage_map *smap;
> unsigned int i;
> u32 nbuckets;
> + u32 pages;
> u64 cost;
> + int ret;
>
> smap = kzalloc(sizeof(*smap), GFP_USER | __GFP_NOWARN);
> if (!smap)
> @@ -635,13 +637,19 @@ static struct bpf_map *bpf_sk_storage_map_alloc(union bpf_attr *attr)
>
> smap->bucket_log = ilog2(roundup_pow_of_two(num_possible_cpus()));
> nbuckets = 1U << smap->bucket_log;
> + cost = sizeof(*smap->buckets) * nbuckets + sizeof(*smap);
> + pages = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT;
> +
> + ret = bpf_map_precharge_memlock(pages);
> + if (ret < 0)
> + return ERR_PTR(ret);
> +
> smap->buckets = kvcalloc(sizeof(*smap->buckets), nbuckets,
> GFP_USER | __GFP_NOWARN);
> if (!smap->buckets) {
> kfree(smap);
> return ERR_PTR(-ENOMEM);
> }
> - cost = sizeof(*smap->buckets) * nbuckets + sizeof(*smap);
>
> for (i = 0; i < nbuckets; i++) {
> INIT_HLIST_HEAD(&smap->buckets[i].list);
> @@ -651,7 +659,7 @@ static struct bpf_map *bpf_sk_storage_map_alloc(union bpf_attr *attr)
> smap->elem_size = sizeof(struct bpf_sk_storage_elem) + attr->value_size;
> smap->cache_idx = (unsigned int)atomic_inc_return(&cache_idx) %
> BPF_SK_STORAGE_CACHE_SIZE;
> - smap->map.pages = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT;
> + smap->map.pages = pages;
>
> return &smap->map;
> }
> --
> 2.20.1
>
