On Tue, Mar 05, 2024 at 12:22:00PM -0800, Yonghong Song wrote:
SNIP
> +
> +int bpf_skmsg_link_create(const union bpf_attr *attr, struct bpf_prog *prog)
> +{
> + struct bpf_link_primer link_primer;
> + struct bpf_skmsg_link *skmsg_link;
> + enum bpf_attach_type attach_type;
> + struct bpf_map *map;
> + int ret;
> +
> + if (attr->link_create.flags)
> + return -EINVAL;
> +
> + map = bpf_map_get_with_uref(attr->link_create.target_fd);
> + if (IS_ERR(map))
> + return PTR_ERR(map);
> +
> + skmsg_link = kzalloc(sizeof(*skmsg_link), GFP_USER);
> + if (!skmsg_link) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + attach_type = attr->link_create.attach_type;
> + bpf_link_init(&skmsg_link->link, BPF_LINK_TYPE_SK_MSG, &bpf_skmsg_link_ops, prog);
> + skmsg_link->map = map;
> + skmsg_link->attach_type = attach_type;
> +
> + ret = bpf_link_prime(&skmsg_link->link, &link_primer);
> + if (ret) {
> + kfree(skmsg_link);
> + goto out;
> + }
> +
> + ret = sock_map_prog_update(map, prog, NULL, attach_type);
> + if (ret) {
> + bpf_link_cleanup(&link_primer);
> + goto out;
> + }
> +
> + bpf_prog_inc(prog);
there's already prog ref taken in link_create, is this needed?
also I might be missing some skmsg logic, but I can't see thi
being released
jirka
> +
> + return bpf_link_settle(&link_primer);
> +
> +out:
> + bpf_map_put_with_uref(map);
> + return ret;
> +}
> diff --git a/net/core/sock_map.c b/net/core/sock_map.c
> index 27d733c0f65e..63372bc368f1 100644
> --- a/net/core/sock_map.c
> +++ b/net/core/sock_map.c
> @@ -24,8 +24,6 @@ struct bpf_stab {
> #define SOCK_CREATE_FLAG_MASK \
> (BPF_F_NUMA_NODE | BPF_F_RDONLY | BPF_F_WRONLY)
>
> -static int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog,
> - struct bpf_prog *old, u32 which);
> static struct sk_psock_progs *sock_map_progs(struct bpf_map *map);
>
> static struct bpf_map *sock_map_alloc(union bpf_attr *attr)
> @@ -1488,8 +1486,8 @@ static int sock_map_prog_lookup(struct bpf_map *map, struct bpf_prog ***pprog,
> return 0;
> }
>
> -static int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog,
> - struct bpf_prog *old, u32 which)
> +int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog,
> + struct bpf_prog *old, u32 which)
> {
> struct bpf_prog **pprog;
> int ret;
> diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
> index a241f407c234..c7d2a5fcf37a 100644
> --- a/tools/include/uapi/linux/bpf.h
> +++ b/tools/include/uapi/linux/bpf.h
> @@ -1129,6 +1129,7 @@ enum bpf_link_type {
> BPF_LINK_TYPE_TCX = 11,
> BPF_LINK_TYPE_UPROBE_MULTI = 12,
> BPF_LINK_TYPE_NETKIT = 13,
> + BPF_LINK_TYPE_SK_MSG = 14,
> __MAX_BPF_LINK_TYPE,
> };
>
> @@ -6699,6 +6700,10 @@ struct bpf_link_info {
> __u32 ifindex;
> __u32 attach_type;
> } netkit;
> + struct {
> + __u32 map_id;
> + __u32 attach_type;
> + } skmsg;
> };
> } __attribute__((aligned(8)));
>
> --
> 2.43.0
>
>
