diff mbox series

[bpf-next,v6,1/5] bpf: Add bpf_link support for sk_msg and sk_skb progs

Message ID 20240408152431.4161022-1-yonghong.song@linux.dev (mailing list archive)
State Superseded
Delegated to: BPF
Headers show
Series bpf: Add bpf_link support for sk_msg and sk_skb progs | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR success PR summary
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next, async
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 7516 this patch: 7516
netdev/build_tools success Errors and warnings before: 1 this patch: 1
netdev/cc_maintainers warning 11 maintainers not CCed: pabeni@redhat.com kuba@kernel.org edumazet@google.com netdev@vger.kernel.org jolsa@kernel.org kpsingh@kernel.org sdf@google.com martin.lau@linux.dev haoluo@google.com eddyz87@gmail.com song@kernel.org
netdev/build_clang success Errors and warnings before: 1228 this patch: 1228
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 7898 this patch: 7898
netdev/checkpatch warning WARNING: line length of 81 exceeds 80 columns WARNING: line length of 82 exceeds 80 columns WARNING: line length of 83 exceeds 80 columns WARNING: line length of 84 exceeds 80 columns WARNING: line length of 85 exceeds 80 columns WARNING: line length of 86 exceeds 80 columns WARNING: line length of 87 exceeds 80 columns WARNING: line length of 89 exceeds 80 columns WARNING: line length of 90 exceeds 80 columns WARNING: line length of 92 exceeds 80 columns WARNING: line length of 94 exceeds 80 columns WARNING: line length of 96 exceeds 80 columns
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 6 this patch: 6
netdev/source_inline success Was 0 now: 0
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Commit Message

Yonghong Song April 8, 2024, 3:24 p.m. UTC 
Add bpf_link support for sk_msg and sk_skb programs. We have an
internal request to support bpf_link for sk_msg programs so user
space can have a uniform handling with bpf_link based libbpf
APIs. Using bpf_link based libbpf API also has a benefit which
makes system robust by decoupling prog life cycle and
attachment life cycle.

Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
---
 include/linux/bpf.h            |   6 +
 include/linux/skmsg.h          |   4 +
 include/uapi/linux/bpf.h       |   5 +
 kernel/bpf/syscall.c           |   4 +
 net/core/sock_map.c            | 261 +++++++++++++++++++++++++++++++--
 tools/include/uapi/linux/bpf.h |   5 +
 6 files changed, 269 insertions(+), 16 deletions(-)

Comments

Eduard Zingerman April 9, 2024, 9:52 a.m. UTC | #1 
On Mon, 2024-04-08 at 08:24 -0700, Yonghong Song wrote:

[...]


> +/* Handle the following two cases:
> + * case 1: link != NULL, prog != NULL, old != NULL
> + * case 2: link != NULL, prog != NULL, old == NULL
> + */
> +static int sock_map_link_update_prog(struct bpf_link *link,
> +				     struct bpf_prog *prog,
> +				     struct bpf_prog *old)
> +{
> +	const struct sockmap_link *sockmap_link = container_of(link, struct sockmap_link, link);
> +	struct bpf_prog **pprog, *old_link_prog;
> +	struct bpf_link **plink;
> +	int ret = 0;
> +
> +	mutex_lock(&sockmap_mutex);
> +
> +	/* If old prog is not NULL, ensure old prog is the same as link->prog. */
> +	if (old && link->prog != old) {
> +		ret = -EPERM;
> +		goto out;
> +	}
> +	/* Ensure link->prog has the same type/attach_type as the new prog. */
> +	if (link->prog->type != prog->type ||
> +	    link->prog->expected_attach_type != prog->expected_attach_type) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +
> +	ret = sock_map_prog_link_lookup(sockmap_link->map, &pprog, &plink,
> +					sockmap_link->attach_type);
> +	if (ret)
> +		goto out;
> +
> +	/* return error if the stored bpf_link does not match the incoming bpf_link. */
> +	if (link != *plink)
> +		return -EBUSY;

Hi Yonghong,

Sorry, this was a mistake on my side,
this needs a 'goto out' in order to unlock the mutex.

Thanks,
Eduard

> +
> +	if (old) {
> +		ret = psock_replace_prog(pprog, prog, old);
> +		if (ret)
> +			goto out;
> +	} else {
> +		psock_set_prog(pprog, prog);
> +	}
> +
> +	bpf_prog_inc(prog);
> +	old_link_prog = xchg(&link->prog, prog);
> +	bpf_prog_put(old_link_prog);
> +
> +out:
> +	mutex_unlock(&sockmap_mutex);
> +	return ret;
> +}
Yonghong Song April 9, 2024, 3:28 p.m. UTC | #2 
On 4/9/24 2:52 AM, Eduard Zingerman wrote:
> On Mon, 2024-04-08 at 08:24 -0700, Yonghong Song wrote:
>
> [...]
>
>
>> +/* Handle the following two cases:
>> + * case 1: link != NULL, prog != NULL, old != NULL
>> + * case 2: link != NULL, prog != NULL, old == NULL
>> + */
>> +static int sock_map_link_update_prog(struct bpf_link *link,
>> +				     struct bpf_prog *prog,
>> +				     struct bpf_prog *old)
>> +{
>> +	const struct sockmap_link *sockmap_link = container_of(link, struct sockmap_link, link);
>> +	struct bpf_prog **pprog, *old_link_prog;
>> +	struct bpf_link **plink;
>> +	int ret = 0;
>> +
>> +	mutex_lock(&sockmap_mutex);
>> +
>> +	/* If old prog is not NULL, ensure old prog is the same as link->prog. */
>> +	if (old && link->prog != old) {
>> +		ret = -EPERM;
>> +		goto out;
>> +	}
>> +	/* Ensure link->prog has the same type/attach_type as the new prog. */
>> +	if (link->prog->type != prog->type ||
>> +	    link->prog->expected_attach_type != prog->expected_attach_type) {
>> +		ret = -EINVAL;
>> +		goto out;
>> +	}
>> +
>> +	ret = sock_map_prog_link_lookup(sockmap_link->map, &pprog, &plink,
>> +					sockmap_link->attach_type);
>> +	if (ret)
>> +		goto out;
>> +
>> +	/* return error if the stored bpf_link does not match the incoming bpf_link. */
>> +	if (link != *plink)
>> +		return -EBUSY;
> Hi Yonghong,
>
> Sorry, this was a mistake on my side,
> this needs a 'goto out' in order to unlock the mutex.

It is my fault as well since I missed it too. Will send a revision later today
just in case there are more comments.

>
> Thanks,
> Eduard
>
>> +
>> +	if (old) {
>> +		ret = psock_replace_prog(pprog, prog, old);
>> +		if (ret)
>> +			goto out;
>> +	} else {
>> +		psock_set_prog(pprog, prog);
>> +	}
>> +
>> +	bpf_prog_inc(prog);
>> +	old_link_prog = xchg(&link->prog, prog);
>> +	bpf_prog_put(old_link_prog);
>> +
>> +out:
>> +	mutex_unlock(&sockmap_mutex);
>> +	return ret;
>> +}
diff mbox series

Patch

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 62762390c93d..5034c1b4ded7 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -2996,6 +2996,7 @@  int sock_map_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype);
 int sock_map_update_elem_sys(struct bpf_map *map, void *key, void *value, u64 flags);
 int sock_map_bpf_prog_query(const union bpf_attr *attr,
 			    union bpf_attr __user *uattr);
+int sock_map_link_create(const union bpf_attr *attr, struct bpf_prog *prog);
 
 void sock_map_unhash(struct sock *sk);
 void sock_map_destroy(struct sock *sk);
@@ -3094,6 +3095,11 @@  static inline int sock_map_bpf_prog_query(const union bpf_attr *attr,
 {
 	return -EINVAL;
 }
+
+static inline int sock_map_link_create(const union bpf_attr *attr, struct bpf_prog *prog)
+{
+	return -EOPNOTSUPP;
+}
 #endif /* CONFIG_BPF_SYSCALL */
 #endif /* CONFIG_NET && CONFIG_BPF_SYSCALL */
 
diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h
index e65ec3fd2799..9c8dd4c01412 100644
--- a/include/linux/skmsg.h
+++ b/include/linux/skmsg.h
@@ -58,6 +58,10 @@  struct sk_psock_progs {
 	struct bpf_prog			*stream_parser;
 	struct bpf_prog			*stream_verdict;
 	struct bpf_prog			*skb_verdict;
+	struct bpf_link			*msg_parser_link;
+	struct bpf_link			*stream_parser_link;
+	struct bpf_link			*stream_verdict_link;
+	struct bpf_link			*skb_verdict_link;
 };
 
 enum sk_psock_state_bits {
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 6fe9f11c8abe..cee0a7915c08 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1135,6 +1135,7 @@  enum bpf_link_type {
 	BPF_LINK_TYPE_TCX = 11,
 	BPF_LINK_TYPE_UPROBE_MULTI = 12,
 	BPF_LINK_TYPE_NETKIT = 13,
+	BPF_LINK_TYPE_SOCKMAP = 14,
 	__MAX_BPF_LINK_TYPE,
 };
 
@@ -6724,6 +6725,10 @@  struct bpf_link_info {
 			__u32 ifindex;
 			__u32 attach_type;
 		} netkit;
+		struct {
+			__u32 map_id;
+			__u32 attach_type;
+		} sockmap;
 	};
 } __attribute__((aligned(8)));
 
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index e44c276e8617..7d392ec83655 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -5213,6 +5213,10 @@  static int link_create(union bpf_attr *attr, bpfptr_t uattr)
 	case BPF_PROG_TYPE_SK_LOOKUP:
 		ret = netns_bpf_link_create(attr, prog);
 		break;
+	case BPF_PROG_TYPE_SK_MSG:
+	case BPF_PROG_TYPE_SK_SKB:
+		ret = sock_map_link_create(attr, prog);
+		break;
 #ifdef CONFIG_NET
 	case BPF_PROG_TYPE_XDP:
 		ret = bpf_xdp_link_attach(attr, prog);
diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index 27d733c0f65e..2deda1637752 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -24,8 +24,16 @@  struct bpf_stab {
 #define SOCK_CREATE_FLAG_MASK				\
 	(BPF_F_NUMA_NODE | BPF_F_RDONLY | BPF_F_WRONLY)
 
+/* This mutex is used to
+ *  - protect race between prog/link attach/detach and link prog update, and
+ *  - protect race between releasing and accessing map in bpf_link.
+ * A single global mutex lock is used since it is expected contention is low.
+ */
+static DEFINE_MUTEX(sockmap_mutex);
+
 static int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog,
-				struct bpf_prog *old, u32 which);
+				struct bpf_prog *old, struct bpf_link *link,
+				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)
@@ -71,7 +79,9 @@  int sock_map_get_from_fd(const union bpf_attr *attr, struct bpf_prog *prog)
 	map = __bpf_map_get(f);
 	if (IS_ERR(map))
 		return PTR_ERR(map);
-	ret = sock_map_prog_update(map, prog, NULL, attr->attach_type);
+	mutex_lock(&sockmap_mutex);
+	ret = sock_map_prog_update(map, prog, NULL, NULL, attr->attach_type);
+	mutex_unlock(&sockmap_mutex);
 	fdput(f);
 	return ret;
 }
@@ -103,7 +113,9 @@  int sock_map_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype)
 		goto put_prog;
 	}
 
-	ret = sock_map_prog_update(map, NULL, prog, attr->attach_type);
+	mutex_lock(&sockmap_mutex);
+	ret = sock_map_prog_update(map, NULL, prog, NULL, attr->attach_type);
+	mutex_unlock(&sockmap_mutex);
 put_prog:
 	bpf_prog_put(prog);
 put_map:
@@ -1454,55 +1466,84 @@  static struct sk_psock_progs *sock_map_progs(struct bpf_map *map)
 	return NULL;
 }
 
-static int sock_map_prog_lookup(struct bpf_map *map, struct bpf_prog ***pprog,
-				u32 which)
+static int sock_map_prog_link_lookup(struct bpf_map *map, struct bpf_prog ***pprog,
+				     struct bpf_link ***plink, u32 which)
 {
 	struct sk_psock_progs *progs = sock_map_progs(map);
+	struct bpf_prog **cur_pprog;
+	struct bpf_link **cur_plink;
 
 	if (!progs)
 		return -EOPNOTSUPP;
 
 	switch (which) {
 	case BPF_SK_MSG_VERDICT:
-		*pprog = &progs->msg_parser;
+		cur_pprog = &progs->msg_parser;
+		cur_plink = &progs->msg_parser_link;
 		break;
 #if IS_ENABLED(CONFIG_BPF_STREAM_PARSER)
 	case BPF_SK_SKB_STREAM_PARSER:
-		*pprog = &progs->stream_parser;
+		cur_pprog = &progs->stream_parser;
+		cur_plink = &progs->stream_parser_link;
 		break;
 #endif
 	case BPF_SK_SKB_STREAM_VERDICT:
 		if (progs->skb_verdict)
 			return -EBUSY;
-		*pprog = &progs->stream_verdict;
+		cur_pprog = &progs->stream_verdict;
+		cur_plink = &progs->stream_verdict_link;
 		break;
 	case BPF_SK_SKB_VERDICT:
 		if (progs->stream_verdict)
 			return -EBUSY;
-		*pprog = &progs->skb_verdict;
+		cur_pprog = &progs->skb_verdict;
+		cur_plink = &progs->skb_verdict_link;
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}
 
+	*pprog = cur_pprog;
+	if (plink)
+		*plink = cur_plink;
 	return 0;
 }
 
+/* Handle the following four cases:
+ * prog_attach: prog != NULL, old == NULL, link == NULL
+ * prog_detach: prog == NULL, old != NULL, link == NULL
+ * link_attach: prog != NULL, old == NULL, link != NULL
+ * link_detach: prog == NULL, old != NULL, link != NULL
+ */
 static int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog,
-				struct bpf_prog *old, u32 which)
+				struct bpf_prog *old, struct bpf_link *link,
+				u32 which)
 {
 	struct bpf_prog **pprog;
+	struct bpf_link **plink;
 	int ret;
 
-	ret = sock_map_prog_lookup(map, &pprog, which);
+	ret = sock_map_prog_link_lookup(map, &pprog, &plink, which);
 	if (ret)
 		return ret;
 
-	if (old)
-		return psock_replace_prog(pprog, prog, old);
+	/* for prog_attach/prog_detach/link_attach, return error if a bpf_link
+	 * exists for that prog.
+	 */
+	if ((!link || prog) && *plink)
+		return -EBUSY;
 
-	psock_set_prog(pprog, prog);
-	return 0;
+	if (old) {
+		ret = psock_replace_prog(pprog, prog, old);
+		if (!ret)
+			*plink = NULL;
+	} else {
+		psock_set_prog(pprog, prog);
+		if (link)
+			*plink = link;
+	}
+
+	return ret;
 }
 
 int sock_map_bpf_prog_query(const union bpf_attr *attr,
@@ -1527,7 +1568,7 @@  int sock_map_bpf_prog_query(const union bpf_attr *attr,
 
 	rcu_read_lock();
 
-	ret = sock_map_prog_lookup(map, &pprog, attr->query.attach_type);
+	ret = sock_map_prog_link_lookup(map, &pprog, NULL, attr->query.attach_type);
 	if (ret)
 		goto end;
 
@@ -1657,6 +1698,194 @@  void sock_map_close(struct sock *sk, long timeout)
 }
 EXPORT_SYMBOL_GPL(sock_map_close);
 
+struct sockmap_link {
+	struct bpf_link link;
+	struct bpf_map *map;
+	enum bpf_attach_type attach_type;
+};
+
+static void sock_map_link_release(struct bpf_link *link)
+{
+	struct sockmap_link *sockmap_link = container_of(link, struct sockmap_link, link);
+
+	mutex_lock(&sockmap_mutex);
+	if (!sockmap_link->map)
+		goto out;
+
+	WARN_ON_ONCE(sock_map_prog_update(sockmap_link->map, NULL, link->prog, link,
+					  sockmap_link->attach_type));
+
+	bpf_map_put_with_uref(sockmap_link->map);
+	sockmap_link->map = NULL;
+out:
+	mutex_unlock(&sockmap_mutex);
+}
+
+static int sock_map_link_detach(struct bpf_link *link)
+{
+	sock_map_link_release(link);
+	return 0;
+}
+
+static void sock_map_link_dealloc(struct bpf_link *link)
+{
+	kfree(link);
+}
+
+/* Handle the following two cases:
+ * case 1: link != NULL, prog != NULL, old != NULL
+ * case 2: link != NULL, prog != NULL, old == NULL
+ */
+static int sock_map_link_update_prog(struct bpf_link *link,
+				     struct bpf_prog *prog,
+				     struct bpf_prog *old)
+{
+	const struct sockmap_link *sockmap_link = container_of(link, struct sockmap_link, link);
+	struct bpf_prog **pprog, *old_link_prog;
+	struct bpf_link **plink;
+	int ret = 0;
+
+	mutex_lock(&sockmap_mutex);
+
+	/* If old prog is not NULL, ensure old prog is the same as link->prog. */
+	if (old && link->prog != old) {
+		ret = -EPERM;
+		goto out;
+	}
+	/* Ensure link->prog has the same type/attach_type as the new prog. */
+	if (link->prog->type != prog->type ||
+	    link->prog->expected_attach_type != prog->expected_attach_type) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = sock_map_prog_link_lookup(sockmap_link->map, &pprog, &plink,
+					sockmap_link->attach_type);
+	if (ret)
+		goto out;
+
+	/* return error if the stored bpf_link does not match the incoming bpf_link. */
+	if (link != *plink)
+		return -EBUSY;
+
+	if (old) {
+		ret = psock_replace_prog(pprog, prog, old);
+		if (ret)
+			goto out;
+	} else {
+		psock_set_prog(pprog, prog);
+	}
+
+	bpf_prog_inc(prog);
+	old_link_prog = xchg(&link->prog, prog);
+	bpf_prog_put(old_link_prog);
+
+out:
+	mutex_unlock(&sockmap_mutex);
+	return ret;
+}
+
+static u32 sock_map_link_get_map_id(const struct sockmap_link *sockmap_link)
+{
+	u32 map_id = 0;
+
+	mutex_lock(&sockmap_mutex);
+	if (sockmap_link->map)
+		map_id = sockmap_link->map->id;
+	mutex_unlock(&sockmap_mutex);
+	return map_id;
+}
+
+static int sock_map_link_fill_info(const struct bpf_link *link,
+				   struct bpf_link_info *info)
+{
+	const struct sockmap_link *sockmap_link = container_of(link, struct sockmap_link, link);
+	u32 map_id = sock_map_link_get_map_id(sockmap_link);
+
+	info->sockmap.map_id = map_id;
+	info->sockmap.attach_type = sockmap_link->attach_type;
+	return 0;
+}
+
+static void sock_map_link_show_fdinfo(const struct bpf_link *link,
+				      struct seq_file *seq)
+{
+	const struct sockmap_link *sockmap_link = container_of(link, struct sockmap_link, link);
+	u32 map_id = sock_map_link_get_map_id(sockmap_link);
+
+	seq_printf(seq, "map_id:\t%u\n", map_id);
+	seq_printf(seq, "attach_type:\t%u\n", sockmap_link->attach_type);
+}
+
+static const struct bpf_link_ops sock_map_link_ops = {
+	.release = sock_map_link_release,
+	.dealloc = sock_map_link_dealloc,
+	.detach = sock_map_link_detach,
+	.update_prog = sock_map_link_update_prog,
+	.fill_link_info = sock_map_link_fill_info,
+	.show_fdinfo = sock_map_link_show_fdinfo,
+};
+
+int sock_map_link_create(const union bpf_attr *attr, struct bpf_prog *prog)
+{
+	struct bpf_link_primer link_primer;
+	struct sockmap_link *sockmap_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);
+	if (map->map_type != BPF_MAP_TYPE_SOCKMAP && map->map_type != BPF_MAP_TYPE_SOCKHASH) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	sockmap_link = kzalloc(sizeof(*sockmap_link), GFP_USER);
+	if (!sockmap_link) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	attach_type = attr->link_create.attach_type;
+	bpf_link_init(&sockmap_link->link, BPF_LINK_TYPE_SOCKMAP, &sock_map_link_ops, prog);
+	sockmap_link->map = map;
+	sockmap_link->attach_type = attach_type;
+
+	ret = bpf_link_prime(&sockmap_link->link, &link_primer);
+	if (ret) {
+		kfree(sockmap_link);
+		goto out;
+	}
+
+	mutex_lock(&sockmap_mutex);
+	ret = sock_map_prog_update(map, prog, NULL, &sockmap_link->link, attach_type);
+	mutex_unlock(&sockmap_mutex);
+	if (ret) {
+		bpf_link_cleanup(&link_primer);
+		goto out;
+	}
+
+	/* Increase refcnt for the prog since when old prog is replaced with
+	 * psock_replace_prog() and psock_set_prog() its refcnt will be decreased.
+	 *
+	 * Actually, we do not need to increase refcnt for the prog since bpf_link
+	 * will hold a reference. But in order to have less complexity w.r.t.
+	 * replacing/setting prog, let us increase the refcnt to make things simpler.
+	 */
+	bpf_prog_inc(prog);
+
+	return bpf_link_settle(&link_primer);
+
+out:
+	bpf_map_put_with_uref(map);
+	return ret;
+}
+
 static int sock_map_iter_attach_target(struct bpf_prog *prog,
 				       union bpf_iter_link_info *linfo,
 				       struct bpf_iter_aux_info *aux)
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 6fe9f11c8abe..cee0a7915c08 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -1135,6 +1135,7 @@  enum bpf_link_type {
 	BPF_LINK_TYPE_TCX = 11,
 	BPF_LINK_TYPE_UPROBE_MULTI = 12,
 	BPF_LINK_TYPE_NETKIT = 13,
+	BPF_LINK_TYPE_SOCKMAP = 14,
 	__MAX_BPF_LINK_TYPE,
 };
 
@@ -6724,6 +6725,10 @@  struct bpf_link_info {
 			__u32 ifindex;
 			__u32 attach_type;
 		} netkit;
+		struct {
+			__u32 map_id;
+			__u32 attach_type;
+		} sockmap;
 	};
 } __attribute__((aligned(8)));