Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next

Steffen Klassert says:

====================
1) Refactor selftests to use an array of structs in xfrm_fill_key().
   From Gautam Menghani.

2) Drop an unused argument from xfrm_policy_match.
   From Hongbin Wang.

3) Support collect metadata mode for xfrm interfaces.
   From Eyal Birger.

4) Add netlink extack support to xfrm.
   From Sabrina Dubroca.

Please note, there is a merge conflict in:

include/net/dst_metadata.h

between commit:

0a28bfd4 ("net/macsec: Add MACsec skb_metadata_dst Tx Data path support")

from the net-next tree and commit:

5182a5d4 ("net: allow storing xfrm interface metadata in metadata_dst")

from the ipsec-next tree.

Can be solved as done in linux-next.

Please pull or let me know if there are problems.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/dst_metadata.h

@@ -11,6 +11,7 @@ enum metadata_type {
 	METADATA_IP_TUNNEL,
 	METADATA_HW_PORT_MUX,
 	METADATA_MACSEC,
+	METADATA_XFRM,
 };
 
 struct hw_port_info {
@@ -22,6 +23,11 @@ struct macsec_info {
 	sci_t sci;
 };
 
+struct xfrm_md_info {
+	u32 if_id;
+	int link;
+};
+
 struct metadata_dst {
 	struct dst_entry		dst;
 	enum metadata_type		type;
@@ -29,6 +35,7 @@ struct metadata_dst {
 		struct ip_tunnel_info	tun_info;
 		struct hw_port_info	port_info;
 		struct macsec_info	macsec_info;
+		struct xfrm_md_info	xfrm_info;
 	} u;
 };
 
@@ -60,6 +67,27 @@ skb_tunnel_info(const struct sk_buff *skb)
 	return NULL;
 }
 
+static inline struct xfrm_md_info *lwt_xfrm_info(struct lwtunnel_state *lwt)
+{
+	return (struct xfrm_md_info *)lwt->data;
+}
+
+static inline struct xfrm_md_info *skb_xfrm_md_info(const struct sk_buff *skb)
+{
+	struct metadata_dst *md_dst = skb_metadata_dst(skb);
+	struct dst_entry *dst;
+
+	if (md_dst && md_dst->type == METADATA_XFRM)
+		return &md_dst->u.xfrm_info;
+
+	dst = skb_dst(skb);
+	if (dst && dst->lwtstate &&
+	    dst->lwtstate->type == LWTUNNEL_ENCAP_XFRM)
+		return lwt_xfrm_info(dst->lwtstate);
+
+	return NULL;
+}
+
 static inline bool skb_valid_dst(const struct sk_buff *skb)
 {
 	struct dst_entry *dst = skb_dst(skb);
@@ -92,6 +120,9 @@ static inline int skb_metadata_dst_cmp(const struct sk_buff *skb_a,
 	case METADATA_MACSEC:
 		return memcmp(&a->u.macsec_info, &b->u.macsec_info,
 			      sizeof(a->u.macsec_info));
+	case METADATA_XFRM:
+		return memcmp(&a->u.xfrm_info, &b->u.xfrm_info,
+			      sizeof(a->u.xfrm_info));
 	default:
 		return 1;
 	}

include/net/ipcomp.h

@@ -22,7 +22,7 @@ struct xfrm_state;
 int ipcomp_input(struct xfrm_state *x, struct sk_buff *skb);
 int ipcomp_output(struct xfrm_state *x, struct sk_buff *skb);
 void ipcomp_destroy(struct xfrm_state *x);
-int ipcomp_init_state(struct xfrm_state *x);
+int ipcomp_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack);
 
 static inline struct ip_comp_hdr *ip_comp_hdr(const struct sk_buff *skb)
 {

include/net/xfrm.h

@@ -312,9 +312,15 @@ struct km_event {
 	struct net *net;
 };
 
+struct xfrm_if_decode_session_result {
+	struct net *net;
+	u32 if_id;
+};
+
 struct xfrm_if_cb {
-	struct xfrm_if	*(*decode_session)(struct sk_buff *skb,
-					   unsigned short family);
+	bool (*decode_session)(struct sk_buff *skb,
+			       unsigned short family,
+			       struct xfrm_if_decode_session_result *res);
 };
 
 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb);
@@ -399,7 +405,8 @@ struct xfrm_type {
 #define XFRM_TYPE_LOCAL_COADDR	4
 #define XFRM_TYPE_REMOTE_COADDR	8
 
-	int			(*init_state)(struct xfrm_state *x);
+	int			(*init_state)(struct xfrm_state *x,
+					      struct netlink_ext_ack *extack);
 	void			(*destructor)(struct xfrm_state *);
 	int			(*input)(struct xfrm_state *, struct sk_buff *skb);
 	int			(*output)(struct xfrm_state *, struct sk_buff *pskb);
@@ -985,6 +992,7 @@ void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev);
 struct xfrm_if_parms {
 	int link;		/* ifindex of underlying L2 interface */
 	u32 if_id;		/* interface identifyer */
+	bool collect_md;
 };
 
 struct xfrm_if {
@@ -1573,9 +1581,10 @@ int xfrm_dev_state_flush(struct net *net, struct net_device *dev, bool task_vali
 void xfrm_sad_getinfo(struct net *net, struct xfrmk_sadinfo *si);
 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si);
 u32 xfrm_replay_seqhi(struct xfrm_state *x, __be32 net_seq);
-int xfrm_init_replay(struct xfrm_state *x);
+int xfrm_init_replay(struct xfrm_state *x, struct netlink_ext_ack *extack);
 u32 xfrm_state_mtu(struct xfrm_state *x, int mtu);
-int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload);
+int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload,
+		      struct netlink_ext_ack *extack);
 int xfrm_init_state(struct xfrm_state *x);
 int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type);
 int xfrm_input_resume(struct sk_buff *skb, int nexthdr);
@@ -1879,7 +1888,8 @@ void xfrm_dev_resume(struct sk_buff *skb);
 void xfrm_dev_backlog(struct softnet_data *sd);
 struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t features, bool *again);
 int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
-		       struct xfrm_user_offload *xuo);
+		       struct xfrm_user_offload *xuo,
+		       struct netlink_ext_ack *extack);
 bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x);
 
 static inline void xfrm_dev_state_advance_esn(struct xfrm_state *x)
@@ -1942,7 +1952,7 @@ static inline struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_fea
 	return skb;
 }
 
-static inline int xfrm_dev_state_add(struct net *net, struct xfrm_state *x, struct xfrm_user_offload *xuo)
+static inline int xfrm_dev_state_add(struct net *net, struct xfrm_state *x, struct xfrm_user_offload *xuo, struct netlink_ext_ack *extack)
 {
 	return 0;
 }

include/uapi/linux/if_link.h

@@ -695,6 +695,7 @@ enum {
 	IFLA_XFRM_UNSPEC,
 	IFLA_XFRM_LINK,
 	IFLA_XFRM_IF_ID,
+	IFLA_XFRM_COLLECT_METADATA,
 	__IFLA_XFRM_MAX
 };
 

include/uapi/linux/lwtunnel.h

@@ -15,6 +15,7 @@ enum lwtunnel_encap_types {
 	LWTUNNEL_ENCAP_SEG6_LOCAL,
 	LWTUNNEL_ENCAP_RPL,
 	LWTUNNEL_ENCAP_IOAM6,
+	LWTUNNEL_ENCAP_XFRM,
 	__LWTUNNEL_ENCAP_MAX,
 };
 
@@ -111,4 +112,13 @@ enum {
 
 #define LWT_BPF_MAX_HEADROOM 256
 
+enum {
+	LWT_XFRM_UNSPEC,
+	LWT_XFRM_IF_ID,
+	LWT_XFRM_LINK,
+	__LWT_XFRM_MAX,
+};
+
+#define LWT_XFRM_MAX (__LWT_XFRM_MAX - 1)
+
 #endif /* _UAPI_LWTUNNEL_H_ */

net/core/lwtunnel.c

@@ -50,6 +50,7 @@ static const char *lwtunnel_encap_str(enum lwtunnel_encap_types encap_type)
 		return "IOAM6";
 	case LWTUNNEL_ENCAP_IP6:
 	case LWTUNNEL_ENCAP_IP:
+	case LWTUNNEL_ENCAP_XFRM:
 	case LWTUNNEL_ENCAP_NONE:
 	case __LWTUNNEL_ENCAP_MAX:
 		/* should not have got here */

net/ipv4/ah4.c

@@ -471,30 +471,38 @@ static int ah4_err(struct sk_buff *skb, u32 info)
 	return 0;
 }
 
-static int ah_init_state(struct xfrm_state *x)
+static int ah_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	struct ah_data *ahp = NULL;
 	struct xfrm_algo_desc *aalg_desc;
 	struct crypto_ahash *ahash;
 
-	if (!x->aalg)
+	if (!x->aalg) {
+		NL_SET_ERR_MSG(extack, "AH requires a state with an AUTH algorithm");
 		goto error;
+	}
 
-	if (x->encap)
+	if (x->encap) {
+		NL_SET_ERR_MSG(extack, "AH is not compatible with encapsulation");
 		goto error;
+	}
 
 	ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
 	if (!ahp)
 		return -ENOMEM;
 
 	ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0);
-	if (IS_ERR(ahash))
+	if (IS_ERR(ahash)) {
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
+	}
 
 	ahp->ahash = ahash;
 	if (crypto_ahash_setkey(ahash, x->aalg->alg_key,
-				(x->aalg->alg_key_len + 7) / 8))
+				(x->aalg->alg_key_len + 7) / 8)) {
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
+	}
 
 	/*
 	 * Lookup the algorithm description maintained by xfrm_algo,
@@ -507,10 +515,7 @@ static int ah_init_state(struct xfrm_state *x)
 
 	if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
 	    crypto_ahash_digestsize(ahash)) {
-		pr_info("%s: %s digestsize %u != %u\n",
-			__func__, x->aalg->alg_name,
-			crypto_ahash_digestsize(ahash),
-			aalg_desc->uinfo.auth.icv_fullbits / 8);
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
 	}
 

net/ipv4/esp4.c

@@ -1008,16 +1008,17 @@ static void esp_destroy(struct xfrm_state *x)
 	crypto_free_aead(aead);
 }
 
-static int esp_init_aead(struct xfrm_state *x)
+static int esp_init_aead(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	char aead_name[CRYPTO_MAX_ALG_NAME];
 	struct crypto_aead *aead;
 	int err;
 
-	err = -ENAMETOOLONG;
 	if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
-		     x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME)
-		goto error;
+		     x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) {
+		NL_SET_ERR_MSG(extack, "Algorithm name is too long");
+		return -ENAMETOOLONG;
+	}
 
 	aead = crypto_alloc_aead(aead_name, 0, 0);
 	err = PTR_ERR(aead);
@@ -1035,11 +1036,15 @@ static int esp_init_aead(struct xfrm_state *x)
 	if (err)
 		goto error;
 
+	return 0;
+
 error:
+	NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 	return err;
 }
 
-static int esp_init_authenc(struct xfrm_state *x)
+static int esp_init_authenc(struct xfrm_state *x,
+			    struct netlink_ext_ack *extack)
 {
 	struct crypto_aead *aead;
 	struct crypto_authenc_key_param *param;
@@ -1050,10 +1055,6 @@ static int esp_init_authenc(struct xfrm_state *x)
 	unsigned int keylen;
 	int err;
 
-	err = -EINVAL;
-	if (!x->ealg)
-		goto error;
-
 	err = -ENAMETOOLONG;
 
 	if ((x->props.flags & XFRM_STATE_ESN)) {
@@ -1062,22 +1063,28 @@ static int esp_init_authenc(struct xfrm_state *x)
 			     x->geniv ?: "", x->geniv ? "(" : "",
 			     x->aalg ? x->aalg->alg_name : "digest_null",
 			     x->ealg->alg_name,
-			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
+			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) {
+			NL_SET_ERR_MSG(extack, "Algorithm name is too long");
 			goto error;
+		}
 	} else {
 		if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
 			     "%s%sauthenc(%s,%s)%s",
 			     x->geniv ?: "", x->geniv ? "(" : "",
 			     x->aalg ? x->aalg->alg_name : "digest_null",
 			     x->ealg->alg_name,
-			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
+			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) {
+			NL_SET_ERR_MSG(extack, "Algorithm name is too long");
 			goto error;
+		}
 	}
 
 	aead = crypto_alloc_aead(authenc_name, 0, 0);
 	err = PTR_ERR(aead);
-	if (IS_ERR(aead))
+	if (IS_ERR(aead)) {
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
+	}
 
 	x->data = aead;
 
@@ -1107,17 +1114,16 @@ static int esp_init_authenc(struct xfrm_state *x)
 		err = -EINVAL;
 		if (aalg_desc->uinfo.auth.icv_fullbits / 8 !=
 		    crypto_aead_authsize(aead)) {
-			pr_info("ESP: %s digestsize %u != %u\n",
-				x->aalg->alg_name,
-				crypto_aead_authsize(aead),
-				aalg_desc->uinfo.auth.icv_fullbits / 8);
+			NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 			goto free_key;
 		}
 
 		err = crypto_aead_setauthsize(
 			aead, x->aalg->alg_trunc_len / 8);
-		if (err)
+		if (err) {
+			NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 			goto free_key;
+		}
 	}
 
 	param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8);
@@ -1132,7 +1138,7 @@ static int esp_init_authenc(struct xfrm_state *x)
 	return err;
 }
 
-static int esp_init_state(struct xfrm_state *x)
+static int esp_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	struct crypto_aead *aead;
 	u32 align;
@@ -1140,10 +1146,14 @@ static int esp_init_state(struct xfrm_state *x)
 
 	x->data = NULL;
 
-	if (x->aead)
-		err = esp_init_aead(x);
-	else
-		err = esp_init_authenc(x);
+	if (x->aead) {
+		err = esp_init_aead(x, extack);
+	} else if (x->ealg) {
+		err = esp_init_authenc(x, extack);
+	} else {
+		NL_SET_ERR_MSG(extack, "ESP: AEAD or CRYPT must be provided");
+		err = -EINVAL;
+	}
 
 	if (err)
 		goto error;
@@ -1161,6 +1171,7 @@ static int esp_init_state(struct xfrm_state *x)
 
 		switch (encap->encap_type) {
 		default:
+			NL_SET_ERR_MSG(extack, "Unsupported encapsulation type for ESP");
 			err = -EINVAL;
 			goto error;
 		case UDP_ENCAP_ESPINUDP:

net/ipv4/ipcomp.c

@@ -117,7 +117,8 @@ static int ipcomp_tunnel_attach(struct xfrm_state *x)
 	return err;
 }
 
-static int ipcomp4_init_state(struct xfrm_state *x)
+static int ipcomp4_init_state(struct xfrm_state *x,
+			      struct netlink_ext_ack *extack)
 {
 	int err = -EINVAL;
 
@@ -129,17 +130,20 @@ static int ipcomp4_init_state(struct xfrm_state *x)
 		x->props.header_len += sizeof(struct iphdr);
 		break;
 	default:
+		NL_SET_ERR_MSG(extack, "Unsupported XFRM mode for IPcomp");
 		goto out;
 	}
 
-	err = ipcomp_init_state(x);
+	err = ipcomp_init_state(x, extack);
 	if (err)
 		goto out;
 
 	if (x->props.mode == XFRM_MODE_TUNNEL) {
 		err = ipcomp_tunnel_attach(x);
-		if (err)
+		if (err) {
+			NL_SET_ERR_MSG(extack, "Kernel error: failed to initialize the associated state");
 			goto out;
+		}
 	}
 
 	err = 0;

net/ipv4/xfrm4_tunnel.c

@@ -22,13 +22,17 @@ static int ipip_xfrm_rcv(struct xfrm_state *x, struct sk_buff *skb)
 	return ip_hdr(skb)->protocol;
 }
 
-static int ipip_init_state(struct xfrm_state *x)
+static int ipip_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
-	if (x->props.mode != XFRM_MODE_TUNNEL)
+	if (x->props.mode != XFRM_MODE_TUNNEL) {
+		NL_SET_ERR_MSG(extack, "IPv4 tunnel can only be used with tunnel mode");
 		return -EINVAL;
+	}
 
-	if (x->encap)
+	if (x->encap) {
+		NL_SET_ERR_MSG(extack, "IPv4 tunnel is not compatible with encapsulation");
 		return -EINVAL;
+	}
 
 	x->props.header_len = sizeof(struct iphdr);
 

net/ipv6/ah6.c

@@ -666,30 +666,38 @@ static int ah6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 	return 0;
 }
 
-static int ah6_init_state(struct xfrm_state *x)
+static int ah6_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	struct ah_data *ahp = NULL;
 	struct xfrm_algo_desc *aalg_desc;
 	struct crypto_ahash *ahash;
 
-	if (!x->aalg)
+	if (!x->aalg) {
+		NL_SET_ERR_MSG(extack, "AH requires a state with an AUTH algorithm");
 		goto error;
+	}
 
-	if (x->encap)
+	if (x->encap) {
+		NL_SET_ERR_MSG(extack, "AH is not compatible with encapsulation");
 		goto error;
+	}
 
 	ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
 	if (!ahp)
 		return -ENOMEM;
 
 	ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0);
-	if (IS_ERR(ahash))
+	if (IS_ERR(ahash)) {
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
+	}
 
 	ahp->ahash = ahash;
 	if (crypto_ahash_setkey(ahash, x->aalg->alg_key,
-			       (x->aalg->alg_key_len + 7) / 8))
+			       (x->aalg->alg_key_len + 7) / 8)) {
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
+	}
 
 	/*
 	 * Lookup the algorithm description maintained by xfrm_algo,
@@ -702,9 +710,7 @@ static int ah6_init_state(struct xfrm_state *x)
 
 	if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
 	    crypto_ahash_digestsize(ahash)) {
-		pr_info("AH: %s digestsize %u != %u\n",
-			x->aalg->alg_name, crypto_ahash_digestsize(ahash),
-			aalg_desc->uinfo.auth.icv_fullbits/8);
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
 	}
 
@@ -721,6 +727,7 @@ static int ah6_init_state(struct xfrm_state *x)
 		x->props.header_len += sizeof(struct ipv6hdr);
 		break;
 	default:
+		NL_SET_ERR_MSG(extack, "Invalid mode requested for AH, must be one of TRANSPORT, TUNNEL, BEET");
 		goto error;
 	}
 	x->data = ahp;

net/ipv6/esp6.c

@@ -1051,16 +1051,17 @@ static void esp6_destroy(struct xfrm_state *x)
 	crypto_free_aead(aead);
 }
 
-static int esp_init_aead(struct xfrm_state *x)
+static int esp_init_aead(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	char aead_name[CRYPTO_MAX_ALG_NAME];
 	struct crypto_aead *aead;
 	int err;
 
-	err = -ENAMETOOLONG;
 	if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
-		     x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME)
-		goto error;
+		     x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) {
+		NL_SET_ERR_MSG(extack, "Algorithm name is too long");
+		return -ENAMETOOLONG;
+	}
 
 	aead = crypto_alloc_aead(aead_name, 0, 0);
 	err = PTR_ERR(aead);
@@ -1078,11 +1079,15 @@ static int esp_init_aead(struct xfrm_state *x)
 	if (err)
 		goto error;
 
+	return 0;
+
 error:
+	NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 	return err;
 }
 
-static int esp_init_authenc(struct xfrm_state *x)
+static int esp_init_authenc(struct xfrm_state *x,
+			    struct netlink_ext_ack *extack)
 {
 	struct crypto_aead *aead;
 	struct crypto_authenc_key_param *param;
@@ -1093,10 +1098,6 @@ static int esp_init_authenc(struct xfrm_state *x)
 	unsigned int keylen;
 	int err;
 
-	err = -EINVAL;
-	if (!x->ealg)
-		goto error;
-
 	err = -ENAMETOOLONG;
 
 	if ((x->props.flags & XFRM_STATE_ESN)) {
@@ -1105,22 +1106,28 @@ static int esp_init_authenc(struct xfrm_state *x)
 			     x->geniv ?: "", x->geniv ? "(" : "",
 			     x->aalg ? x->aalg->alg_name : "digest_null",
 			     x->ealg->alg_name,
-			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
+			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) {
+			NL_SET_ERR_MSG(extack, "Algorithm name is too long");
 			goto error;
+		}
 	} else {
 		if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
 			     "%s%sauthenc(%s,%s)%s",
 			     x->geniv ?: "", x->geniv ? "(" : "",
 			     x->aalg ? x->aalg->alg_name : "digest_null",
 			     x->ealg->alg_name,
-			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
+			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) {
+			NL_SET_ERR_MSG(extack, "Algorithm name is too long");
 			goto error;
+		}
 	}
 
 	aead = crypto_alloc_aead(authenc_name, 0, 0);
 	err = PTR_ERR(aead);
-	if (IS_ERR(aead))
+	if (IS_ERR(aead)) {
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
+	}
 
 	x->data = aead;
 
@@ -1150,17 +1157,16 @@ static int esp_init_authenc(struct xfrm_state *x)
 		err = -EINVAL;
 		if (aalg_desc->uinfo.auth.icv_fullbits / 8 !=
 		    crypto_aead_authsize(aead)) {
-			pr_info("ESP: %s digestsize %u != %u\n",
-				x->aalg->alg_name,
-				crypto_aead_authsize(aead),
-				aalg_desc->uinfo.auth.icv_fullbits / 8);
+			NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 			goto free_key;
 		}
 
 		err = crypto_aead_setauthsize(
 			aead, x->aalg->alg_trunc_len / 8);
-		if (err)
+		if (err) {
+			NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 			goto free_key;
+		}
 	}
 
 	param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8);
@@ -1175,7 +1181,7 @@ static int esp_init_authenc(struct xfrm_state *x)
 	return err;
 }
 
-static int esp6_init_state(struct xfrm_state *x)
+static int esp6_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	struct crypto_aead *aead;
 	u32 align;
@@ -1183,10 +1189,14 @@ static int esp6_init_state(struct xfrm_state *x)
 
 	x->data = NULL;
 
-	if (x->aead)
-		err = esp_init_aead(x);
-	else
-		err = esp_init_authenc(x);
+	if (x->aead) {
+		err = esp_init_aead(x, extack);
+	} else if (x->ealg) {
+		err = esp_init_authenc(x, extack);
+	} else {
+		NL_SET_ERR_MSG(extack, "ESP: AEAD or CRYPT must be provided");
+		err = -EINVAL;
+	}
 
 	if (err)
 		goto error;
@@ -1214,6 +1224,7 @@ static int esp6_init_state(struct xfrm_state *x)
 
 		switch (encap->encap_type) {
 		default:
+			NL_SET_ERR_MSG(extack, "Unsupported encapsulation type for ESP");
 			err = -EINVAL;
 			goto error;
 		case UDP_ENCAP_ESPINUDP:

net/ipv6/ipcomp6.c

@@ -136,7 +136,8 @@ static int ipcomp6_tunnel_attach(struct xfrm_state *x)
 	return err;
 }
 
-static int ipcomp6_init_state(struct xfrm_state *x)
+static int ipcomp6_init_state(struct xfrm_state *x,
+			      struct netlink_ext_ack *extack)
 {
 	int err = -EINVAL;
 
@@ -148,17 +149,20 @@ static int ipcomp6_init_state(struct xfrm_state *x)
 		x->props.header_len += sizeof(struct ipv6hdr);
 		break;
 	default:
+		NL_SET_ERR_MSG(extack, "Unsupported XFRM mode for IPcomp");
 		goto out;
 	}
 
-	err = ipcomp_init_state(x);
+	err = ipcomp_init_state(x, extack);
 	if (err)
 		goto out;
 
 	if (x->props.mode == XFRM_MODE_TUNNEL) {
 		err = ipcomp6_tunnel_attach(x);
-		if (err)
+		if (err) {
+			NL_SET_ERR_MSG(extack, "Kernel error: failed to initialize the associated state");
 			goto out;
+		}
 	}
 
 	err = 0;

net/ipv6/mip6.c

@@ -247,15 +247,14 @@ static int mip6_destopt_reject(struct xfrm_state *x, struct sk_buff *skb,
 	return err;
 }
 
-static int mip6_destopt_init_state(struct xfrm_state *x)
+static int mip6_destopt_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	if (x->id.spi) {
-		pr_info("%s: spi is not 0: %u\n", __func__, x->id.spi);
+		NL_SET_ERR_MSG(extack, "SPI must be 0");
 		return -EINVAL;
 	}
 	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
-		pr_info("%s: state's mode is not %u: %u\n",
-			__func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
+		NL_SET_ERR_MSG(extack, "XFRM mode must be XFRM_MODE_ROUTEOPTIMIZATION");
 		return -EINVAL;
 	}
 
@@ -333,15 +332,14 @@ static int mip6_rthdr_output(struct xfrm_state *x, struct sk_buff *skb)
 	return 0;
 }
 
-static int mip6_rthdr_init_state(struct xfrm_state *x)
+static int mip6_rthdr_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	if (x->id.spi) {
-		pr_info("%s: spi is not 0: %u\n", __func__, x->id.spi);
+		NL_SET_ERR_MSG(extack, "SPI must be 0");
 		return -EINVAL;
 	}
 	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
-		pr_info("%s: state's mode is not %u: %u\n",
-			__func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
+		NL_SET_ERR_MSG(extack, "XFRM mode must be XFRM_MODE_ROUTEOPTIMIZATION");
 		return -EINVAL;
 	}
 

net/ipv6/xfrm6_tunnel.c

@@ -270,13 +270,17 @@ static int xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 	return 0;
 }
 
-static int xfrm6_tunnel_init_state(struct xfrm_state *x)
+static int xfrm6_tunnel_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
-	if (x->props.mode != XFRM_MODE_TUNNEL)
+	if (x->props.mode != XFRM_MODE_TUNNEL) {
+		NL_SET_ERR_MSG(extack, "IPv6 tunnel can only be used with tunnel mode");
 		return -EINVAL;
+	}
 
-	if (x->encap)
+	if (x->encap) {
+		NL_SET_ERR_MSG(extack, "IPv6 tunnel is not compatible with encapsulation");
 		return -EINVAL;
+	}
 
 	x->props.header_len = sizeof(struct ipv6hdr);
 

net/xfrm/xfrm_device.c

@@ -207,7 +207,8 @@ struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t featur
 EXPORT_SYMBOL_GPL(validate_xmit_xfrm);
 
 int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
-		       struct xfrm_user_offload *xuo)
+		       struct xfrm_user_offload *xuo,
+		       struct netlink_ext_ack *extack)
 {
 	int err;
 	struct dst_entry *dst;
@@ -216,15 +217,21 @@ int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
 	xfrm_address_t *saddr;
 	xfrm_address_t *daddr;
 
-	if (!x->type_offload)
+	if (!x->type_offload) {
+		NL_SET_ERR_MSG(extack, "Type doesn't support offload");
 		return -EINVAL;
+	}
 
 	/* We don't yet support UDP encapsulation and TFC padding. */
-	if (x->encap || x->tfcpad)
+	if (x->encap || x->tfcpad) {
+		NL_SET_ERR_MSG(extack, "Encapsulation and TFC padding can't be offloaded");
 		return -EINVAL;
+	}
 
-	if (xuo->flags & ~(XFRM_OFFLOAD_IPV6 | XFRM_OFFLOAD_INBOUND))
+	if (xuo->flags & ~(XFRM_OFFLOAD_IPV6 | XFRM_OFFLOAD_INBOUND)) {
+		NL_SET_ERR_MSG(extack, "Unrecognized flags in offload request");
 		return -EINVAL;
+	}
 
 	dev = dev_get_by_index(net, xuo->ifindex);
 	if (!dev) {
@@ -256,6 +263,7 @@ int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
 
 	if (x->props.flags & XFRM_STATE_ESN &&
 	    !dev->xfrmdev_ops->xdo_dev_state_advance_esn) {
+		NL_SET_ERR_MSG(extack, "Device doesn't support offload with ESN");
 		xso->dev = NULL;
 		dev_put(dev);
 		return -EINVAL;
@@ -277,8 +285,10 @@ int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
 		xso->real_dev = NULL;
 		netdev_put(dev, &xso->dev_tracker);
 
-		if (err != -EOPNOTSUPP)
+		if (err != -EOPNOTSUPP) {
+			NL_SET_ERR_MSG(extack, "Device failed to offload this state");
 			return err;
+		}
 	}
 
 	return 0;

net/xfrm/xfrm_input.c

@@ -20,6 +20,7 @@
 #include <net/xfrm.h>
 #include <net/ip_tunnels.h>
 #include <net/ip6_tunnel.h>
+#include <net/dst_metadata.h>
 
 #include "xfrm_inout.h"
 
@@ -719,7 +720,8 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 		sp = skb_sec_path(skb);
 		if (sp)
 			sp->olen = 0;
-		skb_dst_drop(skb);
+		if (skb_valid_dst(skb))
+			skb_dst_drop(skb);
 		gro_cells_receive(&gro_cells, skb);
 		return 0;
 	} else {
@@ -737,7 +739,8 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 			sp = skb_sec_path(skb);
 			if (sp)
 				sp->olen = 0;
-			skb_dst_drop(skb);
+			if (skb_valid_dst(skb))
+				skb_dst_drop(skb);
 			gro_cells_receive(&gro_cells, skb);
 			return err;
 		}

net/xfrm/xfrm_interface.c

@@ -41,6 +41,7 @@
 #include <net/addrconf.h>
 #include <net/xfrm.h>
 #include <net/net_namespace.h>
+#include <net/dst_metadata.h>
 #include <net/netns/generic.h>
 #include <linux/etherdevice.h>
 
@@ -56,6 +57,89 @@ static const struct net_device_ops xfrmi_netdev_ops;
 struct xfrmi_net {
 	/* lists for storing interfaces in use */
 	struct xfrm_if __rcu *xfrmi[XFRMI_HASH_SIZE];
+	struct xfrm_if __rcu *collect_md_xfrmi;
+};
+
+static const struct nla_policy xfrm_lwt_policy[LWT_XFRM_MAX + 1] = {
+	[LWT_XFRM_IF_ID]	= NLA_POLICY_MIN(NLA_U32, 1),
+	[LWT_XFRM_LINK]		= NLA_POLICY_MIN(NLA_U32, 1),
+};
+
+static void xfrmi_destroy_state(struct lwtunnel_state *lwt)
+{
+}
+
+static int xfrmi_build_state(struct net *net, struct nlattr *nla,
+			     unsigned int family, const void *cfg,
+			     struct lwtunnel_state **ts,
+			     struct netlink_ext_ack *extack)
+{
+	struct nlattr *tb[LWT_XFRM_MAX + 1];
+	struct lwtunnel_state *new_state;
+	struct xfrm_md_info *info;
+	int ret;
+
+	ret = nla_parse_nested(tb, LWT_XFRM_MAX, nla, xfrm_lwt_policy, extack);
+	if (ret < 0)
+		return ret;
+
+	if (!tb[LWT_XFRM_IF_ID]) {
+		NL_SET_ERR_MSG(extack, "if_id must be set");
+		return -EINVAL;
+	}
+
+	new_state = lwtunnel_state_alloc(sizeof(*info));
+	if (!new_state) {
+		NL_SET_ERR_MSG(extack, "failed to create encap info");
+		return -ENOMEM;
+	}
+
+	new_state->type = LWTUNNEL_ENCAP_XFRM;
+
+	info = lwt_xfrm_info(new_state);
+
+	info->if_id = nla_get_u32(tb[LWT_XFRM_IF_ID]);
+
+	if (tb[LWT_XFRM_LINK])
+		info->link = nla_get_u32(tb[LWT_XFRM_LINK]);
+
+	*ts = new_state;
+	return 0;
+}
+
+static int xfrmi_fill_encap_info(struct sk_buff *skb,
+				 struct lwtunnel_state *lwt)
+{
+	struct xfrm_md_info *info = lwt_xfrm_info(lwt);
+
+	if (nla_put_u32(skb, LWT_XFRM_IF_ID, info->if_id) ||
+	    (info->link && nla_put_u32(skb, LWT_XFRM_LINK, info->link)))
+		return -EMSGSIZE;
+
+	return 0;
+}
+
+static int xfrmi_encap_nlsize(struct lwtunnel_state *lwtstate)
+{
+	return nla_total_size(sizeof(u32)) + /* LWT_XFRM_IF_ID */
+		nla_total_size(sizeof(u32)); /* LWT_XFRM_LINK */
+}
+
+static int xfrmi_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b)
+{
+	struct xfrm_md_info *a_info = lwt_xfrm_info(a);
+	struct xfrm_md_info *b_info = lwt_xfrm_info(b);
+
+	return memcmp(a_info, b_info, sizeof(*a_info));
+}
+
+static const struct lwtunnel_encap_ops xfrmi_encap_ops = {
+	.build_state	= xfrmi_build_state,
+	.destroy_state	= xfrmi_destroy_state,
+	.fill_encap	= xfrmi_fill_encap_info,
+	.get_encap_size = xfrmi_encap_nlsize,
+	.cmp_encap	= xfrmi_encap_cmp,
+	.owner		= THIS_MODULE,
 };
 
 #define for_each_xfrmi_rcu(start, xi) \
@@ -77,17 +161,23 @@ static struct xfrm_if *xfrmi_lookup(struct net *net, struct xfrm_state *x)
 			return xi;
 	}
 
+	xi = rcu_dereference(xfrmn->collect_md_xfrmi);
+	if (xi && (xi->dev->flags & IFF_UP))
+		return xi;
+
 	return NULL;
 }
 
-static struct xfrm_if *xfrmi_decode_session(struct sk_buff *skb,
-					    unsigned short family)
+static bool xfrmi_decode_session(struct sk_buff *skb,
+				 unsigned short family,
+				 struct xfrm_if_decode_session_result *res)
 {
 	struct net_device *dev;
+	struct xfrm_if *xi;
 	int ifindex = 0;
 
 	if (!secpath_exists(skb) || !skb->dev)
-		return NULL;
+		return false;
 
 	switch (family) {
 	case AF_INET6:
@@ -107,11 +197,18 @@ static struct xfrm_if *xfrmi_decode_session(struct sk_buff *skb,
 	}
 
 	if (!dev || !(dev->flags & IFF_UP))
-		return NULL;
+		return false;
 	if (dev->netdev_ops != &xfrmi_netdev_ops)
-		return NULL;
+		return false;
 
-	return netdev_priv(dev);
+	xi = netdev_priv(dev);
+	res->net = xi->net;
+
+	if (xi->p.collect_md)
+		res->if_id = xfrm_input_state(skb)->if_id;
+	else
+		res->if_id = xi->p.if_id;
+	return true;
 }
 
 static void xfrmi_link(struct xfrmi_net *xfrmn, struct xfrm_if *xi)
@@ -157,7 +254,10 @@ static int xfrmi_create(struct net_device *dev)
 	if (err < 0)
 		goto out;
 
-	xfrmi_link(xfrmn, xi);
+	if (xi->p.collect_md)
+		rcu_assign_pointer(xfrmn->collect_md_xfrmi, xi);
+	else
+		xfrmi_link(xfrmn, xi);
 
 	return 0;
 
@@ -185,7 +285,10 @@ static void xfrmi_dev_uninit(struct net_device *dev)
 	struct xfrm_if *xi = netdev_priv(dev);
 	struct xfrmi_net *xfrmn = net_generic(xi->net, xfrmi_net_id);
 
-	xfrmi_unlink(xfrmn, xi);
+	if (xi->p.collect_md)
+		RCU_INIT_POINTER(xfrmn->collect_md_xfrmi, NULL);
+	else
+		xfrmi_unlink(xfrmn, xi);
 }
 
 static void xfrmi_scrub_packet(struct sk_buff *skb, bool xnet)
@@ -214,6 +317,7 @@ static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
 	struct xfrm_state *x;
 	struct xfrm_if *xi;
 	bool xnet;
+	int link;
 
 	if (err && !secpath_exists(skb))
 		return 0;
@@ -224,6 +328,7 @@ static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
 	if (!xi)
 		return 1;
 
+	link = skb->dev->ifindex;
 	dev = xi->dev;
 	skb->dev = dev;
 
@@ -254,6 +359,17 @@ static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
 	}
 
 	xfrmi_scrub_packet(skb, xnet);
+	if (xi->p.collect_md) {
+		struct metadata_dst *md_dst;
+
+		md_dst = metadata_dst_alloc(0, METADATA_XFRM, GFP_ATOMIC);
+		if (!md_dst)
+			return -ENOMEM;
+
+		md_dst->u.xfrm_info.if_id = x->if_id;
+		md_dst->u.xfrm_info.link = link;
+		skb_dst_set(skb, (struct dst_entry *)md_dst);
+	}
 	dev_sw_netstats_rx_add(dev, skb->len);
 
 	return 0;
@@ -269,10 +385,23 @@ xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
 	struct net_device *tdev;
 	struct xfrm_state *x;
 	int err = -1;
+	u32 if_id;
 	int mtu;
 
+	if (xi->p.collect_md) {
+		struct xfrm_md_info *md_info = skb_xfrm_md_info(skb);
+
+		if (unlikely(!md_info))
+			return -EINVAL;
+
+		if_id = md_info->if_id;
+		fl->flowi_oif = md_info->link;
+	} else {
+		if_id = xi->p.if_id;
+	}
+
 	dst_hold(dst);
-	dst = xfrm_lookup_with_ifid(xi->net, dst, fl, NULL, 0, xi->p.if_id);
+	dst = xfrm_lookup_with_ifid(xi->net, dst, fl, NULL, 0, if_id);
 	if (IS_ERR(dst)) {
 		err = PTR_ERR(dst);
 		dst = NULL;
@@ -283,7 +412,7 @@ xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
 	if (!x)
 		goto tx_err_link_failure;
 
-	if (x->if_id != xi->p.if_id)
+	if (x->if_id != if_id)
 		goto tx_err_link_failure;
 
 	tdev = dst->dev;
@@ -633,6 +762,9 @@ static void xfrmi_netlink_parms(struct nlattr *data[],
 
 	if (data[IFLA_XFRM_IF_ID])
 		parms->if_id = nla_get_u32(data[IFLA_XFRM_IF_ID]);
+
+	if (data[IFLA_XFRM_COLLECT_METADATA])
+		parms->collect_md = true;
 }
 
 static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
@@ -645,14 +777,27 @@ static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
 	int err;
 
 	xfrmi_netlink_parms(data, &p);
-	if (!p.if_id) {
-		NL_SET_ERR_MSG(extack, "if_id must be non zero");
-		return -EINVAL;
-	}
+	if (p.collect_md) {
+		struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
 
-	xi = xfrmi_locate(net, &p);
-	if (xi)
-		return -EEXIST;
+		if (p.link || p.if_id) {
+			NL_SET_ERR_MSG(extack, "link and if_id must be zero");
+			return -EINVAL;
+		}
+
+		if (rtnl_dereference(xfrmn->collect_md_xfrmi))
+			return -EEXIST;
+
+	} else {
+		if (!p.if_id) {
+			NL_SET_ERR_MSG(extack, "if_id must be non zero");
+			return -EINVAL;
+		}
+
+		xi = xfrmi_locate(net, &p);
+		if (xi)
+			return -EEXIST;
+	}
 
 	xi = netdev_priv(dev);
 	xi->p = p;
@@ -682,12 +827,22 @@ static int xfrmi_changelink(struct net_device *dev, struct nlattr *tb[],
 		return -EINVAL;
 	}
 
+	if (p.collect_md) {
+		NL_SET_ERR_MSG(extack, "collect_md can't be changed");
+		return -EINVAL;
+	}
+
 	xi = xfrmi_locate(net, &p);
 	if (!xi) {
 		xi = netdev_priv(dev);
 	} else {
 		if (xi->dev != dev)
 			return -EEXIST;
+		if (xi->p.collect_md) {
+			NL_SET_ERR_MSG(extack,
+				       "device can't be changed to collect_md");
+			return -EINVAL;
+		}
 	}
 
 	return xfrmi_update(xi, &p);
@@ -700,6 +855,8 @@ static size_t xfrmi_get_size(const struct net_device *dev)
 		nla_total_size(4) +
 		/* IFLA_XFRM_IF_ID */
 		nla_total_size(4) +
+		/* IFLA_XFRM_COLLECT_METADATA */
+		nla_total_size(0) +
 		0;
 }
 
@@ -709,7 +866,8 @@ static int xfrmi_fill_info(struct sk_buff *skb, const struct net_device *dev)
 	struct xfrm_if_parms *parm = &xi->p;
 
 	if (nla_put_u32(skb, IFLA_XFRM_LINK, parm->link) ||
-	    nla_put_u32(skb, IFLA_XFRM_IF_ID, parm->if_id))
+	    nla_put_u32(skb, IFLA_XFRM_IF_ID, parm->if_id) ||
+	    (xi->p.collect_md && nla_put_flag(skb, IFLA_XFRM_COLLECT_METADATA)))
 		goto nla_put_failure;
 	return 0;
 
@@ -725,8 +883,10 @@ static struct net *xfrmi_get_link_net(const struct net_device *dev)
 }
 
 static const struct nla_policy xfrmi_policy[IFLA_XFRM_MAX + 1] = {
-	[IFLA_XFRM_LINK]	= { .type = NLA_U32 },
-	[IFLA_XFRM_IF_ID]	= { .type = NLA_U32 },
+	[IFLA_XFRM_UNSPEC]		= { .strict_start_type = IFLA_XFRM_COLLECT_METADATA },
+	[IFLA_XFRM_LINK]		= { .type = NLA_U32 },
+	[IFLA_XFRM_IF_ID]		= { .type = NLA_U32 },
+	[IFLA_XFRM_COLLECT_METADATA]	= { .type = NLA_FLAG },
 };
 
 static struct rtnl_link_ops xfrmi_link_ops __read_mostly = {
@@ -762,6 +922,9 @@ static void __net_exit xfrmi_exit_batch_net(struct list_head *net_exit_list)
 			     xip = &xi->next)
 				unregister_netdevice_queue(xi->dev, &list);
 		}
+		xi = rtnl_dereference(xfrmn->collect_md_xfrmi);
+		if (xi)
+			unregister_netdevice_queue(xi->dev, &list);
 	}
 	unregister_netdevice_many(&list);
 	rtnl_unlock();
@@ -999,6 +1162,8 @@ static int __init xfrmi_init(void)
 	if (err < 0)
 		goto rtnl_link_failed;
 
+	lwtunnel_encap_add_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM);
+
 	xfrm_if_register_cb(&xfrm_if_cb);
 
 	return err;
@@ -1017,6 +1182,7 @@ static int __init xfrmi_init(void)
 static void __exit xfrmi_fini(void)
 {
 	xfrm_if_unregister_cb();
+	lwtunnel_encap_del_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM);
 	rtnl_link_unregister(&xfrmi_link_ops);
 	xfrmi4_fini();
 	xfrmi6_fini();

net/xfrm/xfrm_ipcomp.c

@@ -325,18 +325,22 @@ void ipcomp_destroy(struct xfrm_state *x)
 }
 EXPORT_SYMBOL_GPL(ipcomp_destroy);
 
-int ipcomp_init_state(struct xfrm_state *x)
+int ipcomp_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	int err;
 	struct ipcomp_data *ipcd;
 	struct xfrm_algo_desc *calg_desc;
 
 	err = -EINVAL;
-	if (!x->calg)
+	if (!x->calg) {
+		NL_SET_ERR_MSG(extack, "Missing required compression algorithm");
 		goto out;
+	}
 
-	if (x->encap)
+	if (x->encap) {
+		NL_SET_ERR_MSG(extack, "IPComp is not compatible with encapsulation");
 		goto out;
+	}
 
 	err = -ENOMEM;
 	ipcd = kzalloc(sizeof(*ipcd), GFP_KERNEL);

net/xfrm/xfrm_policy.c

@@ -1889,7 +1889,7 @@ EXPORT_SYMBOL(xfrm_policy_walk_done);
  */
 static int xfrm_policy_match(const struct xfrm_policy *pol,
 			     const struct flowi *fl,
-			     u8 type, u16 family, int dir, u32 if_id)
+			     u8 type, u16 family, u32 if_id)
 {
 	const struct xfrm_selector *sel = &pol->selector;
 	int ret = -ESRCH;
@@ -2014,7 +2014,7 @@ static struct xfrm_policy *
 __xfrm_policy_eval_candidates(struct hlist_head *chain,
 			      struct xfrm_policy *prefer,
 			      const struct flowi *fl,
-			      u8 type, u16 family, int dir, u32 if_id)
+			      u8 type, u16 family, u32 if_id)
 {
 	u32 priority = prefer ? prefer->priority : ~0u;
 	struct xfrm_policy *pol;
@@ -2028,7 +2028,7 @@ __xfrm_policy_eval_candidates(struct hlist_head *chain,
 		if (pol->priority > priority)
 			break;
 
-		err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
+		err = xfrm_policy_match(pol, fl, type, family, if_id);
 		if (err) {
 			if (err != -ESRCH)
 				return ERR_PTR(err);
@@ -2053,7 +2053,7 @@ static struct xfrm_policy *
 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
 			    struct xfrm_policy *prefer,
 			    const struct flowi *fl,
-			    u8 type, u16 family, int dir, u32 if_id)
+			    u8 type, u16 family, u32 if_id)
 {
 	struct xfrm_policy *tmp;
 	int i;
@@ -2061,8 +2061,7 @@ xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
 	for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
 		tmp = __xfrm_policy_eval_candidates(cand->res[i],
 						    prefer,
-						    fl, type, family, dir,
-						    if_id);
+						    fl, type, family, if_id);
 		if (!tmp)
 			continue;
 
@@ -2101,7 +2100,7 @@ static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
 
 	ret = NULL;
 	hlist_for_each_entry_rcu(pol, chain, bydst) {
-		err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
+		err = xfrm_policy_match(pol, fl, type, family, if_id);
 		if (err) {
 			if (err == -ESRCH)
 				continue;
@@ -2120,7 +2119,7 @@ static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
 		goto skip_inexact;
 
 	pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
-					  family, dir, if_id);
+					  family, if_id);
 	if (pol) {
 		ret = pol;
 		if (IS_ERR(pol))
@@ -3516,17 +3515,17 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
 	int xerr_idx = -1;
 	const struct xfrm_if_cb *ifcb;
 	struct sec_path *sp;
-	struct xfrm_if *xi;
 	u32 if_id = 0;
 
 	rcu_read_lock();
 	ifcb = xfrm_if_get_cb();
 
 	if (ifcb) {
-		xi = ifcb->decode_session(skb, family);
-		if (xi) {
-			if_id = xi->p.if_id;
-			net = xi->net;
+		struct xfrm_if_decode_session_result r;
+
+		if (ifcb->decode_session(skb, family, &r)) {
+			if_id = r.if_id;
+			net = r.net;
 		}
 	}
 	rcu_read_unlock();

net/xfrm/xfrm_replay.c

@@ -766,18 +766,22 @@ int xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb)
 }
 #endif
 
-int xfrm_init_replay(struct xfrm_state *x)
+int xfrm_init_replay(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
 
 	if (replay_esn) {
 		if (replay_esn->replay_window >
-		    replay_esn->bmp_len * sizeof(__u32) * 8)
+		    replay_esn->bmp_len * sizeof(__u32) * 8) {
+			NL_SET_ERR_MSG(extack, "ESN replay window is too large for the chosen bitmap size");
 			return -EINVAL;
+		}
 
 		if (x->props.flags & XFRM_STATE_ESN) {
-			if (replay_esn->replay_window == 0)
+			if (replay_esn->replay_window == 0) {
+				NL_SET_ERR_MSG(extack, "ESN replay window must be > 0");
 				return -EINVAL;
+			}
 			x->repl_mode = XFRM_REPLAY_MODE_ESN;
 		} else {
 			x->repl_mode = XFRM_REPLAY_MODE_BMP;

net/xfrm/xfrm_state.c

@@ -2611,7 +2611,8 @@ u32 xfrm_state_mtu(struct xfrm_state *x, int mtu)
 }
 EXPORT_SYMBOL_GPL(xfrm_state_mtu);
 
-int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
+int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload,
+		      struct netlink_ext_ack *extack)
 {
 	const struct xfrm_mode *inner_mode;
 	const struct xfrm_mode *outer_mode;
@@ -2626,12 +2627,16 @@ int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
 
 	if (x->sel.family != AF_UNSPEC) {
 		inner_mode = xfrm_get_mode(x->props.mode, x->sel.family);
-		if (inner_mode == NULL)
+		if (inner_mode == NULL) {
+			NL_SET_ERR_MSG(extack, "Requested mode not found");
 			goto error;
+		}
 
 		if (!(inner_mode->flags & XFRM_MODE_FLAG_TUNNEL) &&
-		    family != x->sel.family)
+		    family != x->sel.family) {
+			NL_SET_ERR_MSG(extack, "Only tunnel modes can accommodate a change of family");
 			goto error;
+		}
 
 		x->inner_mode = *inner_mode;
 	} else {
@@ -2639,11 +2644,15 @@ int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
 		int iafamily = AF_INET;
 
 		inner_mode = xfrm_get_mode(x->props.mode, x->props.family);
-		if (inner_mode == NULL)
+		if (inner_mode == NULL) {
+			NL_SET_ERR_MSG(extack, "Requested mode not found");
 			goto error;
+		}
 
-		if (!(inner_mode->flags & XFRM_MODE_FLAG_TUNNEL))
+		if (!(inner_mode->flags & XFRM_MODE_FLAG_TUNNEL)) {
+			NL_SET_ERR_MSG(extack, "Only tunnel modes can accommodate an AF_UNSPEC selector");
 			goto error;
+		}
 
 		x->inner_mode = *inner_mode;
 
@@ -2658,24 +2667,27 @@ int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
 	}
 
 	x->type = xfrm_get_type(x->id.proto, family);
-	if (x->type == NULL)
+	if (x->type == NULL) {
+		NL_SET_ERR_MSG(extack, "Requested type not found");
 		goto error;
+	}
 
 	x->type_offload = xfrm_get_type_offload(x->id.proto, family, offload);
 
-	err = x->type->init_state(x);
+	err = x->type->init_state(x, extack);
 	if (err)
 		goto error;
 
 	outer_mode = xfrm_get_mode(x->props.mode, family);
 	if (!outer_mode) {
+		NL_SET_ERR_MSG(extack, "Requested mode not found");
 		err = -EPROTONOSUPPORT;
 		goto error;
 	}
 
 	x->outer_mode = *outer_mode;
 	if (init_replay) {
-		err = xfrm_init_replay(x);
+		err = xfrm_init_replay(x, extack);
 		if (err)
 			goto error;
 	}
@@ -2690,7 +2702,7 @@ int xfrm_init_state(struct xfrm_state *x)
 {
 	int err;
 
-	err = __xfrm_init_state(x, true, false);
+	err = __xfrm_init_state(x, true, false, NULL);
 	if (!err)
 		x->km.state = XFRM_STATE_VALID;
 

net/xfrm/xfrm_user.c

@@ -35,7 +35,8 @@
 #endif
 #include <asm/unaligned.h>
 
-static int verify_one_alg(struct nlattr **attrs, enum xfrm_attr_type_t type)
+static int verify_one_alg(struct nlattr **attrs, enum xfrm_attr_type_t type,
+			  struct netlink_ext_ack *extack)
 {
 	struct nlattr *rt = attrs[type];
 	struct xfrm_algo *algp;
@@ -44,8 +45,10 @@ static int verify_one_alg(struct nlattr **attrs, enum xfrm_attr_type_t type)
 		return 0;
 
 	algp = nla_data(rt);
-	if (nla_len(rt) < (int)xfrm_alg_len(algp))
+	if (nla_len(rt) < (int)xfrm_alg_len(algp)) {
+		NL_SET_ERR_MSG(extack, "Invalid AUTH/CRYPT/COMP attribute length");
 		return -EINVAL;
+	}
 
 	switch (type) {
 	case XFRMA_ALG_AUTH:
@@ -54,6 +57,7 @@ static int verify_one_alg(struct nlattr **attrs, enum xfrm_attr_type_t type)
 		break;
 
 	default:
+		NL_SET_ERR_MSG(extack, "Invalid algorithm attribute type");
 		return -EINVAL;
 	}
 
@@ -61,7 +65,8 @@ static int verify_one_alg(struct nlattr **attrs, enum xfrm_attr_type_t type)
 	return 0;
 }
 
-static int verify_auth_trunc(struct nlattr **attrs)
+static int verify_auth_trunc(struct nlattr **attrs,
+			     struct netlink_ext_ack *extack)
 {
 	struct nlattr *rt = attrs[XFRMA_ALG_AUTH_TRUNC];
 	struct xfrm_algo_auth *algp;
@@ -70,14 +75,16 @@ static int verify_auth_trunc(struct nlattr **attrs)
 		return 0;
 
 	algp = nla_data(rt);
-	if (nla_len(rt) < (int)xfrm_alg_auth_len(algp))
+	if (nla_len(rt) < (int)xfrm_alg_auth_len(algp)) {
+		NL_SET_ERR_MSG(extack, "Invalid AUTH_TRUNC attribute length");
 		return -EINVAL;
+	}
 
 	algp->alg_name[sizeof(algp->alg_name) - 1] = '\0';
 	return 0;
 }
 
-static int verify_aead(struct nlattr **attrs)
+static int verify_aead(struct nlattr **attrs, struct netlink_ext_ack *extack)
 {
 	struct nlattr *rt = attrs[XFRMA_ALG_AEAD];
 	struct xfrm_algo_aead *algp;
@@ -86,8 +93,10 @@ static int verify_aead(struct nlattr **attrs)
 		return 0;
 
 	algp = nla_data(rt);
-	if (nla_len(rt) < (int)aead_len(algp))
+	if (nla_len(rt) < (int)aead_len(algp)) {
+		NL_SET_ERR_MSG(extack, "Invalid AEAD attribute length");
 		return -EINVAL;
+	}
 
 	algp->alg_name[sizeof(algp->alg_name) - 1] = '\0';
 	return 0;
@@ -102,7 +111,7 @@ static void verify_one_addr(struct nlattr **attrs, enum xfrm_attr_type_t type,
 		*addrp = nla_data(rt);
 }
 
-static inline int verify_sec_ctx_len(struct nlattr **attrs)
+static inline int verify_sec_ctx_len(struct nlattr **attrs, struct netlink_ext_ack *extack)
 {
 	struct nlattr *rt = attrs[XFRMA_SEC_CTX];
 	struct xfrm_user_sec_ctx *uctx;
@@ -112,42 +121,59 @@ static inline int verify_sec_ctx_len(struct nlattr **attrs)
 
 	uctx = nla_data(rt);
 	if (uctx->len > nla_len(rt) ||
-	    uctx->len != (sizeof(struct xfrm_user_sec_ctx) + uctx->ctx_len))
+	    uctx->len != (sizeof(struct xfrm_user_sec_ctx) + uctx->ctx_len)) {
+		NL_SET_ERR_MSG(extack, "Invalid security context length");
 		return -EINVAL;
+	}
 
 	return 0;
 }
 
 static inline int verify_replay(struct xfrm_usersa_info *p,
-				struct nlattr **attrs)
+				struct nlattr **attrs,
+				struct netlink_ext_ack *extack)
 {
 	struct nlattr *rt = attrs[XFRMA_REPLAY_ESN_VAL];
 	struct xfrm_replay_state_esn *rs;
 
-	if (!rt)
-		return (p->flags & XFRM_STATE_ESN) ? -EINVAL : 0;
+	if (!rt) {
+		if (p->flags & XFRM_STATE_ESN) {
+			NL_SET_ERR_MSG(extack, "Missing required attribute for ESN");
+			return -EINVAL;
+		}
+		return 0;
+	}
 
 	rs = nla_data(rt);
 
-	if (rs->bmp_len > XFRMA_REPLAY_ESN_MAX / sizeof(rs->bmp[0]) / 8)
+	if (rs->bmp_len > XFRMA_REPLAY_ESN_MAX / sizeof(rs->bmp[0]) / 8) {
+		NL_SET_ERR_MSG(extack, "ESN bitmap length must be <= 128");
 		return -EINVAL;
+	}
 
 	if (nla_len(rt) < (int)xfrm_replay_state_esn_len(rs) &&
-	    nla_len(rt) != sizeof(*rs))
+	    nla_len(rt) != sizeof(*rs)) {
+		NL_SET_ERR_MSG(extack, "ESN attribute is too short to fit the full bitmap length");
 		return -EINVAL;
+	}
 
 	/* As only ESP and AH support ESN feature. */
-	if ((p->id.proto != IPPROTO_ESP) && (p->id.proto != IPPROTO_AH))
+	if ((p->id.proto != IPPROTO_ESP) && (p->id.proto != IPPROTO_AH)) {
+		NL_SET_ERR_MSG(extack, "ESN only supported for ESP and AH");
 		return -EINVAL;
+	}
 
-	if (p->replay_window != 0)
+	if (p->replay_window != 0) {
+		NL_SET_ERR_MSG(extack, "ESN not compatible with legacy replay_window");
 		return -EINVAL;
+	}
 
 	return 0;
 }
 
 static int verify_newsa_info(struct xfrm_usersa_info *p,
-			     struct nlattr **attrs)
+			     struct nlattr **attrs,
+			     struct netlink_ext_ack *extack)
 {
 	int err;
 
@@ -161,10 +187,12 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
 		break;
 #else
 		err = -EAFNOSUPPORT;
+		NL_SET_ERR_MSG(extack, "IPv6 support disabled");
 		goto out;
 #endif
 
 	default:
+		NL_SET_ERR_MSG(extack, "Invalid address family");
 		goto out;
 	}
 
@@ -173,65 +201,98 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
 		break;
 
 	case AF_INET:
-		if (p->sel.prefixlen_d > 32 || p->sel.prefixlen_s > 32)
+		if (p->sel.prefixlen_d > 32 || p->sel.prefixlen_s > 32) {
+			NL_SET_ERR_MSG(extack, "Invalid prefix length in selector (must be <= 32 for IPv4)");
 			goto out;
+		}
 
 		break;
 
 	case AF_INET6:
 #if IS_ENABLED(CONFIG_IPV6)
-		if (p->sel.prefixlen_d > 128 || p->sel.prefixlen_s > 128)
+		if (p->sel.prefixlen_d > 128 || p->sel.prefixlen_s > 128) {
+			NL_SET_ERR_MSG(extack, "Invalid prefix length in selector (must be <= 128 for IPv6)");
 			goto out;
+		}
 
 		break;
 #else
+		NL_SET_ERR_MSG(extack, "IPv6 support disabled");
 		err = -EAFNOSUPPORT;
 		goto out;
 #endif
 
 	default:
+		NL_SET_ERR_MSG(extack, "Invalid address family in selector");
 		goto out;
 	}
 
 	err = -EINVAL;
 	switch (p->id.proto) {
 	case IPPROTO_AH:
-		if ((!attrs[XFRMA_ALG_AUTH]	&&
-		     !attrs[XFRMA_ALG_AUTH_TRUNC]) ||
-		    attrs[XFRMA_ALG_AEAD]	||
+		if (!attrs[XFRMA_ALG_AUTH]	&&
+		    !attrs[XFRMA_ALG_AUTH_TRUNC]) {
+			NL_SET_ERR_MSG(extack, "Missing required attribute for AH: AUTH_TRUNC or AUTH");
+			goto out;
+		}
+
+		if (attrs[XFRMA_ALG_AEAD]	||
 		    attrs[XFRMA_ALG_CRYPT]	||
 		    attrs[XFRMA_ALG_COMP]	||
-		    attrs[XFRMA_TFCPAD])
+		    attrs[XFRMA_TFCPAD]) {
+			NL_SET_ERR_MSG(extack, "Invalid attributes for AH: AEAD, CRYPT, COMP, TFCPAD");
 			goto out;
+		}
 		break;
 
 	case IPPROTO_ESP:
-		if (attrs[XFRMA_ALG_COMP])
+		if (attrs[XFRMA_ALG_COMP]) {
+			NL_SET_ERR_MSG(extack, "Invalid attribute for ESP: COMP");
 			goto out;
+		}
+
 		if (!attrs[XFRMA_ALG_AUTH] &&
 		    !attrs[XFRMA_ALG_AUTH_TRUNC] &&
 		    !attrs[XFRMA_ALG_CRYPT] &&
-		    !attrs[XFRMA_ALG_AEAD])
+		    !attrs[XFRMA_ALG_AEAD]) {
+			NL_SET_ERR_MSG(extack, "Missing required attribute for ESP: at least one of AUTH, AUTH_TRUNC, CRYPT, AEAD");
 			goto out;
+		}
+
 		if ((attrs[XFRMA_ALG_AUTH] ||
 		     attrs[XFRMA_ALG_AUTH_TRUNC] ||
 		     attrs[XFRMA_ALG_CRYPT]) &&
-		    attrs[XFRMA_ALG_AEAD])
+		    attrs[XFRMA_ALG_AEAD]) {
+			NL_SET_ERR_MSG(extack, "Invalid attribute combination for ESP: AEAD can't be used with AUTH, AUTH_TRUNC, CRYPT");
 			goto out;
+		}
+
 		if (attrs[XFRMA_TFCPAD] &&
-		    p->mode != XFRM_MODE_TUNNEL)
+		    p->mode != XFRM_MODE_TUNNEL) {
+			NL_SET_ERR_MSG(extack, "TFC padding can only be used in tunnel mode");
 			goto out;
+		}
 		break;
 
 	case IPPROTO_COMP:
-		if (!attrs[XFRMA_ALG_COMP]	||
-		    attrs[XFRMA_ALG_AEAD]	||
+		if (!attrs[XFRMA_ALG_COMP]) {
+			NL_SET_ERR_MSG(extack, "Missing required attribute for COMP: COMP");
+			goto out;
+		}
+
+		if (attrs[XFRMA_ALG_AEAD]	||
 		    attrs[XFRMA_ALG_AUTH]	||
 		    attrs[XFRMA_ALG_AUTH_TRUNC]	||
 		    attrs[XFRMA_ALG_CRYPT]	||
-		    attrs[XFRMA_TFCPAD]		||
-		    (ntohl(p->id.spi) >= 0x10000))
+		    attrs[XFRMA_TFCPAD]) {
+			NL_SET_ERR_MSG(extack, "Invalid attributes for COMP: AEAD, AUTH, AUTH_TRUNC, CRYPT, TFCPAD");
 			goto out;
+		}
+
+		if (ntohl(p->id.spi) >= 0x10000) {
+			NL_SET_ERR_MSG(extack, "SPI is too large for COMP (must be < 0x10000)");
+			goto out;
+		}
 		break;
 
 #if IS_ENABLED(CONFIG_IPV6)
@@ -244,29 +305,36 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
 		    attrs[XFRMA_ALG_CRYPT]	||
 		    attrs[XFRMA_ENCAP]		||
 		    attrs[XFRMA_SEC_CTX]	||
-		    attrs[XFRMA_TFCPAD]		||
-		    !attrs[XFRMA_COADDR])
+		    attrs[XFRMA_TFCPAD]) {
+			NL_SET_ERR_MSG(extack, "Invalid attributes for DSTOPTS/ROUTING");
 			goto out;
+		}
+
+		if (!attrs[XFRMA_COADDR]) {
+			NL_SET_ERR_MSG(extack, "Missing required COADDR attribute for DSTOPTS/ROUTING");
+			goto out;
+		}
 		break;
 #endif
 
 	default:
+		NL_SET_ERR_MSG(extack, "Unsupported protocol");
 		goto out;
 	}
 
-	if ((err = verify_aead(attrs)))
+	if ((err = verify_aead(attrs, extack)))
 		goto out;
-	if ((err = verify_auth_trunc(attrs)))
+	if ((err = verify_auth_trunc(attrs, extack)))
 		goto out;
-	if ((err = verify_one_alg(attrs, XFRMA_ALG_AUTH)))
+	if ((err = verify_one_alg(attrs, XFRMA_ALG_AUTH, extack)))
 		goto out;
-	if ((err = verify_one_alg(attrs, XFRMA_ALG_CRYPT)))
+	if ((err = verify_one_alg(attrs, XFRMA_ALG_CRYPT, extack)))
 		goto out;
-	if ((err = verify_one_alg(attrs, XFRMA_ALG_COMP)))
+	if ((err = verify_one_alg(attrs, XFRMA_ALG_COMP, extack)))
 		goto out;
-	if ((err = verify_sec_ctx_len(attrs)))
+	if ((err = verify_sec_ctx_len(attrs, extack)))
 		goto out;
-	if ((err = verify_replay(p, attrs)))
+	if ((err = verify_replay(p, attrs, extack)))
 		goto out;
 
 	err = -EINVAL;
@@ -278,14 +346,19 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
 		break;
 
 	default:
+		NL_SET_ERR_MSG(extack, "Unsupported mode");
 		goto out;
 	}
 
 	err = 0;
 
-	if (attrs[XFRMA_MTIMER_THRESH])
-		if (!attrs[XFRMA_ENCAP])
+	if (attrs[XFRMA_MTIMER_THRESH]) {
+		if (!attrs[XFRMA_ENCAP]) {
+			NL_SET_ERR_MSG(extack, "MTIMER_THRESH attribute can only be set on ENCAP states");
 			err = -EINVAL;
+			goto out;
+		}
+	}
 
 out:
 	return err;
@@ -293,7 +366,7 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
 
 static int attach_one_algo(struct xfrm_algo **algpp, u8 *props,
 			   struct xfrm_algo_desc *(*get_byname)(const char *, int),
-			   struct nlattr *rta)
+			   struct nlattr *rta, struct netlink_ext_ack *extack)
 {
 	struct xfrm_algo *p, *ualg;
 	struct xfrm_algo_desc *algo;
@@ -304,8 +377,10 @@ static int attach_one_algo(struct xfrm_algo **algpp, u8 *props,
 	ualg = nla_data(rta);
 
 	algo = get_byname(ualg->alg_name, 1);
-	if (!algo)
+	if (!algo) {
+		NL_SET_ERR_MSG(extack, "Requested COMP algorithm not found");
 		return -ENOSYS;
+	}
 	*props = algo->desc.sadb_alg_id;
 
 	p = kmemdup(ualg, xfrm_alg_len(ualg), GFP_KERNEL);
@@ -317,7 +392,8 @@ static int attach_one_algo(struct xfrm_algo **algpp, u8 *props,
 	return 0;
 }
 
-static int attach_crypt(struct xfrm_state *x, struct nlattr *rta)
+static int attach_crypt(struct xfrm_state *x, struct nlattr *rta,
+			struct netlink_ext_ack *extack)
 {
 	struct xfrm_algo *p, *ualg;
 	struct xfrm_algo_desc *algo;
@@ -328,8 +404,10 @@ static int attach_crypt(struct xfrm_state *x, struct nlattr *rta)
 	ualg = nla_data(rta);
 
 	algo = xfrm_ealg_get_byname(ualg->alg_name, 1);
-	if (!algo)
+	if (!algo) {
+		NL_SET_ERR_MSG(extack, "Requested CRYPT algorithm not found");
 		return -ENOSYS;
+	}
 	x->props.ealgo = algo->desc.sadb_alg_id;
 
 	p = kmemdup(ualg, xfrm_alg_len(ualg), GFP_KERNEL);
@@ -343,7 +421,7 @@ static int attach_crypt(struct xfrm_state *x, struct nlattr *rta)
 }
 
 static int attach_auth(struct xfrm_algo_auth **algpp, u8 *props,
-		       struct nlattr *rta)
+		       struct nlattr *rta, struct netlink_ext_ack *extack)
 {
 	struct xfrm_algo *ualg;
 	struct xfrm_algo_auth *p;
@@ -355,8 +433,10 @@ static int attach_auth(struct xfrm_algo_auth **algpp, u8 *props,
 	ualg = nla_data(rta);
 
 	algo = xfrm_aalg_get_byname(ualg->alg_name, 1);
-	if (!algo)
+	if (!algo) {
+		NL_SET_ERR_MSG(extack, "Requested AUTH algorithm not found");
 		return -ENOSYS;
+	}
 	*props = algo->desc.sadb_alg_id;
 
 	p = kmalloc(sizeof(*p) + (ualg->alg_key_len + 7) / 8, GFP_KERNEL);
@@ -373,7 +453,7 @@ static int attach_auth(struct xfrm_algo_auth **algpp, u8 *props,
 }
 
 static int attach_auth_trunc(struct xfrm_algo_auth **algpp, u8 *props,
-			     struct nlattr *rta)
+			     struct nlattr *rta, struct netlink_ext_ack *extack)
 {
 	struct xfrm_algo_auth *p, *ualg;
 	struct xfrm_algo_desc *algo;
@@ -384,10 +464,14 @@ static int attach_auth_trunc(struct xfrm_algo_auth **algpp, u8 *props,
 	ualg = nla_data(rta);
 
 	algo = xfrm_aalg_get_byname(ualg->alg_name, 1);
-	if (!algo)
+	if (!algo) {
+		NL_SET_ERR_MSG(extack, "Requested AUTH_TRUNC algorithm not found");
 		return -ENOSYS;
-	if (ualg->alg_trunc_len > algo->uinfo.auth.icv_fullbits)
+	}
+	if (ualg->alg_trunc_len > algo->uinfo.auth.icv_fullbits) {
+		NL_SET_ERR_MSG(extack, "Invalid length requested for truncated ICV");
 		return -EINVAL;
+	}
 	*props = algo->desc.sadb_alg_id;
 
 	p = kmemdup(ualg, xfrm_alg_auth_len(ualg), GFP_KERNEL);
@@ -402,7 +486,8 @@ static int attach_auth_trunc(struct xfrm_algo_auth **algpp, u8 *props,
 	return 0;
 }
 
-static int attach_aead(struct xfrm_state *x, struct nlattr *rta)
+static int attach_aead(struct xfrm_state *x, struct nlattr *rta,
+		       struct netlink_ext_ack *extack)
 {
 	struct xfrm_algo_aead *p, *ualg;
 	struct xfrm_algo_desc *algo;
@@ -413,8 +498,10 @@ static int attach_aead(struct xfrm_state *x, struct nlattr *rta)
 	ualg = nla_data(rta);
 
 	algo = xfrm_aead_get_byname(ualg->alg_name, ualg->alg_icv_len, 1);
-	if (!algo)
+	if (!algo) {
+		NL_SET_ERR_MSG(extack, "Requested AEAD algorithm not found");
 		return -ENOSYS;
+	}
 	x->props.ealgo = algo->desc.sadb_alg_id;
 
 	p = kmemdup(ualg, aead_len(ualg), GFP_KERNEL);
@@ -579,7 +666,8 @@ static void xfrm_smark_init(struct nlattr **attrs, struct xfrm_mark *m)
 static struct xfrm_state *xfrm_state_construct(struct net *net,
 					       struct xfrm_usersa_info *p,
 					       struct nlattr **attrs,
-					       int *errp)
+					       int *errp,
+					       struct netlink_ext_ack *extack)
 {
 	struct xfrm_state *x = xfrm_state_alloc(net);
 	int err = -ENOMEM;
@@ -606,21 +694,21 @@ static struct xfrm_state *xfrm_state_construct(struct net *net,
 	if (attrs[XFRMA_SA_EXTRA_FLAGS])
 		x->props.extra_flags = nla_get_u32(attrs[XFRMA_SA_EXTRA_FLAGS]);
 
-	if ((err = attach_aead(x, attrs[XFRMA_ALG_AEAD])))
+	if ((err = attach_aead(x, attrs[XFRMA_ALG_AEAD], extack)))
 		goto error;
 	if ((err = attach_auth_trunc(&x->aalg, &x->props.aalgo,
-				     attrs[XFRMA_ALG_AUTH_TRUNC])))
+				     attrs[XFRMA_ALG_AUTH_TRUNC], extack)))
 		goto error;
 	if (!x->props.aalgo) {
 		if ((err = attach_auth(&x->aalg, &x->props.aalgo,
-				       attrs[XFRMA_ALG_AUTH])))
+				       attrs[XFRMA_ALG_AUTH], extack)))
 			goto error;
 	}
-	if ((err = attach_crypt(x, attrs[XFRMA_ALG_CRYPT])))
+	if ((err = attach_crypt(x, attrs[XFRMA_ALG_CRYPT], extack)))
 		goto error;
 	if ((err = attach_one_algo(&x->calg, &x->props.calgo,
 				   xfrm_calg_get_byname,
-				   attrs[XFRMA_ALG_COMP])))
+				   attrs[XFRMA_ALG_COMP], extack)))
 		goto error;
 
 	if (attrs[XFRMA_TFCPAD])
@@ -633,7 +721,7 @@ static struct xfrm_state *xfrm_state_construct(struct net *net,
 	if (attrs[XFRMA_IF_ID])
 		x->if_id = nla_get_u32(attrs[XFRMA_IF_ID]);
 
-	err = __xfrm_init_state(x, false, attrs[XFRMA_OFFLOAD_DEV]);
+	err = __xfrm_init_state(x, false, attrs[XFRMA_OFFLOAD_DEV], extack);
 	if (err)
 		goto error;
 
@@ -653,7 +741,7 @@ static struct xfrm_state *xfrm_state_construct(struct net *net,
 	/* sysctl_xfrm_aevent_etime is in 100ms units */
 	x->replay_maxage = (net->xfrm.sysctl_aevent_etime*HZ)/XFRM_AE_ETH_M;
 
-	if ((err = xfrm_init_replay(x)))
+	if ((err = xfrm_init_replay(x, extack)))
 		goto error;
 
 	/* override default values from above */
@@ -662,7 +750,8 @@ static struct xfrm_state *xfrm_state_construct(struct net *net,
 	/* configure the hardware if offload is requested */
 	if (attrs[XFRMA_OFFLOAD_DEV]) {
 		err = xfrm_dev_state_add(net, x,
-					 nla_data(attrs[XFRMA_OFFLOAD_DEV]));
+					 nla_data(attrs[XFRMA_OFFLOAD_DEV]),
+					 extack);
 		if (err)
 			goto error;
 	}
@@ -678,7 +767,7 @@ static struct xfrm_state *xfrm_state_construct(struct net *net,
 }
 
 static int xfrm_add_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+		       struct nlattr **attrs, struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_usersa_info *p = nlmsg_data(nlh);
@@ -686,11 +775,11 @@ static int xfrm_add_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
 	int err;
 	struct km_event c;
 
-	err = verify_newsa_info(p, attrs);
+	err = verify_newsa_info(p, attrs, extack);
 	if (err)
 		return err;
 
-	x = xfrm_state_construct(net, p, attrs, &err);
+	x = xfrm_state_construct(net, p, attrs, &err, extack);
 	if (!x)
 		return err;
 
@@ -757,7 +846,7 @@ static struct xfrm_state *xfrm_user_state_lookup(struct net *net,
 }
 
 static int xfrm_del_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+		       struct nlattr **attrs, struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_state *x;
@@ -1254,7 +1343,8 @@ static int build_spdinfo(struct sk_buff *skb, struct net *net,
 }
 
 static int xfrm_set_spdinfo(struct sk_buff *skb, struct nlmsghdr *nlh,
-			    struct nlattr **attrs)
+			    struct nlattr **attrs,
+			    struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrmu_spdhthresh *thresh4 = NULL;
@@ -1299,7 +1389,8 @@ static int xfrm_set_spdinfo(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 
 static int xfrm_get_spdinfo(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+			    struct nlattr **attrs,
+			    struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct sk_buff *r_skb;
@@ -1358,7 +1449,8 @@ static int build_sadinfo(struct sk_buff *skb, struct net *net,
 }
 
 static int xfrm_get_sadinfo(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+			    struct nlattr **attrs,
+			    struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct sk_buff *r_skb;
@@ -1378,7 +1470,7 @@ static int xfrm_get_sadinfo(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 
 static int xfrm_get_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+		       struct nlattr **attrs, struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_usersa_id *p = nlmsg_data(nlh);
@@ -1402,7 +1494,8 @@ static int xfrm_get_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 
 static int xfrm_alloc_userspi(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+			      struct nlattr **attrs,
+			      struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_state *x;
@@ -1477,7 +1570,7 @@ static int xfrm_alloc_userspi(struct sk_buff *skb, struct nlmsghdr *nlh,
 	return err;
 }
 
-static int verify_policy_dir(u8 dir)
+static int verify_policy_dir(u8 dir, struct netlink_ext_ack *extack)
 {
 	switch (dir) {
 	case XFRM_POLICY_IN:
@@ -1486,13 +1579,14 @@ static int verify_policy_dir(u8 dir)
 		break;
 
 	default:
+		NL_SET_ERR_MSG(extack, "Invalid policy direction");
 		return -EINVAL;
 	}
 
 	return 0;
 }
 
-static int verify_policy_type(u8 type)
+static int verify_policy_type(u8 type, struct netlink_ext_ack *extack)
 {
 	switch (type) {
 	case XFRM_POLICY_TYPE_MAIN:
@@ -1502,13 +1596,15 @@ static int verify_policy_type(u8 type)
 		break;
 
 	default:
+		NL_SET_ERR_MSG(extack, "Invalid policy type");
 		return -EINVAL;
 	}
 
 	return 0;
 }
 
-static int verify_newpolicy_info(struct xfrm_userpolicy_info *p)
+static int verify_newpolicy_info(struct xfrm_userpolicy_info *p,
+				 struct netlink_ext_ack *extack)
 {
 	int ret;
 
@@ -1520,6 +1616,7 @@ static int verify_newpolicy_info(struct xfrm_userpolicy_info *p)
 		break;
 
 	default:
+		NL_SET_ERR_MSG(extack, "Invalid policy share");
 		return -EINVAL;
 	}
 
@@ -1529,35 +1626,44 @@ static int verify_newpolicy_info(struct xfrm_userpolicy_info *p)
 		break;
 
 	default:
+		NL_SET_ERR_MSG(extack, "Invalid policy action");
 		return -EINVAL;
 	}
 
 	switch (p->sel.family) {
 	case AF_INET:
-		if (p->sel.prefixlen_d > 32 || p->sel.prefixlen_s > 32)
+		if (p->sel.prefixlen_d > 32 || p->sel.prefixlen_s > 32) {
+			NL_SET_ERR_MSG(extack, "Invalid prefix length in selector (must be <= 32 for IPv4)");
 			return -EINVAL;
+		}
 
 		break;
 
 	case AF_INET6:
 #if IS_ENABLED(CONFIG_IPV6)
-		if (p->sel.prefixlen_d > 128 || p->sel.prefixlen_s > 128)
+		if (p->sel.prefixlen_d > 128 || p->sel.prefixlen_s > 128) {
+			NL_SET_ERR_MSG(extack, "Invalid prefix length in selector (must be <= 128 for IPv6)");
 			return -EINVAL;
+		}
 
 		break;
 #else
+		NL_SET_ERR_MSG(extack, "IPv6 support disabled");
 		return  -EAFNOSUPPORT;
 #endif
 
 	default:
+		NL_SET_ERR_MSG(extack, "Invalid selector family");
 		return -EINVAL;
 	}
 
-	ret = verify_policy_dir(p->dir);
+	ret = verify_policy_dir(p->dir, extack);
 	if (ret)
 		return ret;
-	if (p->index && (xfrm_policy_id2dir(p->index) != p->dir))
+	if (p->index && (xfrm_policy_id2dir(p->index) != p->dir)) {
+		NL_SET_ERR_MSG(extack, "Policy index doesn't match direction");
 		return -EINVAL;
+	}
 
 	return 0;
 }
@@ -1599,13 +1705,16 @@ static void copy_templates(struct xfrm_policy *xp, struct xfrm_user_tmpl *ut,
 	}
 }
 
-static int validate_tmpl(int nr, struct xfrm_user_tmpl *ut, u16 family)
+static int validate_tmpl(int nr, struct xfrm_user_tmpl *ut, u16 family,
+			 struct netlink_ext_ack *extack)
 {
 	u16 prev_family;
 	int i;
 
-	if (nr > XFRM_MAX_DEPTH)
+	if (nr > XFRM_MAX_DEPTH) {
+		NL_SET_ERR_MSG(extack, "Template count must be <= XFRM_MAX_DEPTH (" __stringify(XFRM_MAX_DEPTH) ")");
 		return -EINVAL;
+	}
 
 	prev_family = family;
 
@@ -1625,12 +1734,16 @@ static int validate_tmpl(int nr, struct xfrm_user_tmpl *ut, u16 family)
 		case XFRM_MODE_BEET:
 			break;
 		default:
-			if (ut[i].family != prev_family)
+			if (ut[i].family != prev_family) {
+				NL_SET_ERR_MSG(extack, "Mode in template doesn't support a family change");
 				return -EINVAL;
+			}
 			break;
 		}
-		if (ut[i].mode >= XFRM_MODE_MAX)
+		if (ut[i].mode >= XFRM_MODE_MAX) {
+			NL_SET_ERR_MSG(extack, "Mode in template must be < XFRM_MODE_MAX (" __stringify(XFRM_MODE_MAX) ")");
 			return -EINVAL;
+		}
 
 		prev_family = ut[i].family;
 
@@ -1642,17 +1755,21 @@ static int validate_tmpl(int nr, struct xfrm_user_tmpl *ut, u16 family)
 			break;
 #endif
 		default:
+			NL_SET_ERR_MSG(extack, "Invalid family in template");
 			return -EINVAL;
 		}
 
-		if (!xfrm_id_proto_valid(ut[i].id.proto))
+		if (!xfrm_id_proto_valid(ut[i].id.proto)) {
+			NL_SET_ERR_MSG(extack, "Invalid XFRM protocol in template");
 			return -EINVAL;
+		}
 	}
 
 	return 0;
 }
 
-static int copy_from_user_tmpl(struct xfrm_policy *pol, struct nlattr **attrs)
+static int copy_from_user_tmpl(struct xfrm_policy *pol, struct nlattr **attrs,
+			       struct netlink_ext_ack *extack)
 {
 	struct nlattr *rt = attrs[XFRMA_TMPL];
 
@@ -1663,7 +1780,7 @@ static int copy_from_user_tmpl(struct xfrm_policy *pol, struct nlattr **attrs)
 		int nr = nla_len(rt) / sizeof(*utmpl);
 		int err;
 
-		err = validate_tmpl(nr, utmpl, pol->family);
+		err = validate_tmpl(nr, utmpl, pol->family, extack);
 		if (err)
 			return err;
 
@@ -1672,7 +1789,8 @@ static int copy_from_user_tmpl(struct xfrm_policy *pol, struct nlattr **attrs)
 	return 0;
 }
 
-static int copy_from_user_policy_type(u8 *tp, struct nlattr **attrs)
+static int copy_from_user_policy_type(u8 *tp, struct nlattr **attrs,
+				      struct netlink_ext_ack *extack)
 {
 	struct nlattr *rt = attrs[XFRMA_POLICY_TYPE];
 	struct xfrm_userpolicy_type *upt;
@@ -1684,7 +1802,7 @@ static int copy_from_user_policy_type(u8 *tp, struct nlattr **attrs)
 		type = upt->type;
 	}
 
-	err = verify_policy_type(type);
+	err = verify_policy_type(type, extack);
 	if (err)
 		return err;
 
@@ -1719,7 +1837,11 @@ static void copy_to_user_policy(struct xfrm_policy *xp, struct xfrm_userpolicy_i
 	p->share = XFRM_SHARE_ANY; /* XXX xp->share */
 }
 
-static struct xfrm_policy *xfrm_policy_construct(struct net *net, struct xfrm_userpolicy_info *p, struct nlattr **attrs, int *errp)
+static struct xfrm_policy *xfrm_policy_construct(struct net *net,
+						 struct xfrm_userpolicy_info *p,
+						 struct nlattr **attrs,
+						 int *errp,
+						 struct netlink_ext_ack *extack)
 {
 	struct xfrm_policy *xp = xfrm_policy_alloc(net, GFP_KERNEL);
 	int err;
@@ -1731,11 +1853,11 @@ static struct xfrm_policy *xfrm_policy_construct(struct net *net, struct xfrm_us
 
 	copy_from_user_policy(xp, p);
 
-	err = copy_from_user_policy_type(&xp->type, attrs);
+	err = copy_from_user_policy_type(&xp->type, attrs, extack);
 	if (err)
 		goto error;
 
-	if (!(err = copy_from_user_tmpl(xp, attrs)))
+	if (!(err = copy_from_user_tmpl(xp, attrs, extack)))
 		err = copy_from_user_sec_ctx(xp, attrs);
 	if (err)
 		goto error;
@@ -1754,7 +1876,8 @@ static struct xfrm_policy *xfrm_policy_construct(struct net *net, struct xfrm_us
 }
 
 static int xfrm_add_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+			   struct nlattr **attrs,
+			   struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_userpolicy_info *p = nlmsg_data(nlh);
@@ -1763,14 +1886,14 @@ static int xfrm_add_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
 	int err;
 	int excl;
 
-	err = verify_newpolicy_info(p);
+	err = verify_newpolicy_info(p, extack);
 	if (err)
 		return err;
-	err = verify_sec_ctx_len(attrs);
+	err = verify_sec_ctx_len(attrs, extack);
 	if (err)
 		return err;
 
-	xp = xfrm_policy_construct(net, p, attrs, &err);
+	xp = xfrm_policy_construct(net, p, attrs, &err, extack);
 	if (!xp)
 		return err;
 
@@ -2015,7 +2138,7 @@ static bool xfrm_userpolicy_is_valid(__u8 policy)
 }
 
 static int xfrm_set_default(struct sk_buff *skb, struct nlmsghdr *nlh,
-			    struct nlattr **attrs)
+			    struct nlattr **attrs, struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_userpolicy_default *up = nlmsg_data(nlh);
@@ -2036,7 +2159,7 @@ static int xfrm_set_default(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 
 static int xfrm_get_default(struct sk_buff *skb, struct nlmsghdr *nlh,
-			    struct nlattr **attrs)
+			    struct nlattr **attrs, struct netlink_ext_ack *extack)
 {
 	struct sk_buff *r_skb;
 	struct nlmsghdr *r_nlh;
@@ -2066,7 +2189,8 @@ static int xfrm_get_default(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 
 static int xfrm_get_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+			   struct nlattr **attrs,
+			   struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_policy *xp;
@@ -2081,11 +2205,11 @@ static int xfrm_get_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
 	p = nlmsg_data(nlh);
 	delete = nlh->nlmsg_type == XFRM_MSG_DELPOLICY;
 
-	err = copy_from_user_policy_type(&type, attrs);
+	err = copy_from_user_policy_type(&type, attrs, extack);
 	if (err)
 		return err;
 
-	err = verify_policy_dir(p->dir);
+	err = verify_policy_dir(p->dir, extack);
 	if (err)
 		return err;
 
@@ -2101,7 +2225,7 @@ static int xfrm_get_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
 		struct nlattr *rt = attrs[XFRMA_SEC_CTX];
 		struct xfrm_sec_ctx *ctx;
 
-		err = verify_sec_ctx_len(attrs);
+		err = verify_sec_ctx_len(attrs, extack);
 		if (err)
 			return err;
 
@@ -2149,7 +2273,8 @@ static int xfrm_get_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 
 static int xfrm_flush_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+			 struct nlattr **attrs,
+			 struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct km_event c;
@@ -2249,7 +2374,7 @@ static int build_aevent(struct sk_buff *skb, struct xfrm_state *x, const struct
 }
 
 static int xfrm_get_ae(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+		       struct nlattr **attrs, struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_state *x;
@@ -2293,7 +2418,7 @@ static int xfrm_get_ae(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 
 static int xfrm_new_ae(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+		       struct nlattr **attrs, struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_state *x;
@@ -2344,14 +2469,15 @@ static int xfrm_new_ae(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 
 static int xfrm_flush_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+			     struct nlattr **attrs,
+			     struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct km_event c;
 	u8 type = XFRM_POLICY_TYPE_MAIN;
 	int err;
 
-	err = copy_from_user_policy_type(&type, attrs);
+	err = copy_from_user_policy_type(&type, attrs, extack);
 	if (err)
 		return err;
 
@@ -2372,7 +2498,8 @@ static int xfrm_flush_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 
 static int xfrm_add_pol_expire(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+			       struct nlattr **attrs,
+			       struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_policy *xp;
@@ -2383,11 +2510,11 @@ static int xfrm_add_pol_expire(struct sk_buff *skb, struct nlmsghdr *nlh,
 	struct xfrm_mark m;
 	u32 if_id = 0;
 
-	err = copy_from_user_policy_type(&type, attrs);
+	err = copy_from_user_policy_type(&type, attrs, extack);
 	if (err)
 		return err;
 
-	err = verify_policy_dir(p->dir);
+	err = verify_policy_dir(p->dir, extack);
 	if (err)
 		return err;
 
@@ -2403,7 +2530,7 @@ static int xfrm_add_pol_expire(struct sk_buff *skb, struct nlmsghdr *nlh,
 		struct nlattr *rt = attrs[XFRMA_SEC_CTX];
 		struct xfrm_sec_ctx *ctx;
 
-		err = verify_sec_ctx_len(attrs);
+		err = verify_sec_ctx_len(attrs, extack);
 		if (err)
 			return err;
 
@@ -2438,7 +2565,8 @@ static int xfrm_add_pol_expire(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 
 static int xfrm_add_sa_expire(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+			      struct nlattr **attrs,
+			      struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_state *x;
@@ -2472,7 +2600,8 @@ static int xfrm_add_sa_expire(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 
 static int xfrm_add_acquire(struct sk_buff *skb, struct nlmsghdr *nlh,
-		struct nlattr **attrs)
+			    struct nlattr **attrs,
+			    struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_policy *xp;
@@ -2490,15 +2619,15 @@ static int xfrm_add_acquire(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	xfrm_mark_get(attrs, &mark);
 
-	err = verify_newpolicy_info(&ua->policy);
+	err = verify_newpolicy_info(&ua->policy, extack);
 	if (err)
 		goto free_state;
-	err = verify_sec_ctx_len(attrs);
+	err = verify_sec_ctx_len(attrs, extack);
 	if (err)
 		goto free_state;
 
 	/*   build an XP */
-	xp = xfrm_policy_construct(net, &ua->policy, attrs, &err);
+	xp = xfrm_policy_construct(net, &ua->policy, attrs, &err, extack);
 	if (!xp)
 		goto free_state;
 
@@ -2577,7 +2706,7 @@ static int copy_from_user_migrate(struct xfrm_migrate *ma,
 }
 
 static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
-			   struct nlattr **attrs)
+			   struct nlattr **attrs, struct netlink_ext_ack *extack)
 {
 	struct xfrm_userpolicy_id *pi = nlmsg_data(nlh);
 	struct xfrm_migrate m[XFRM_MAX_DEPTH];
@@ -2594,7 +2723,7 @@ static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	kmp = attrs[XFRMA_KMADDRESS] ? &km : NULL;
 
-	err = copy_from_user_policy_type(&type, attrs);
+	err = copy_from_user_policy_type(&type, attrs, extack);
 	if (err)
 		return err;
 
@@ -2623,7 +2752,7 @@ static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 #else
 static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
-			   struct nlattr **attrs)
+			   struct nlattr **attrs, struct netlink_ext_ack *extack)
 {
 	return -ENOPROTOOPT;
 }
@@ -2819,7 +2948,8 @@ static const struct nla_policy xfrma_spd_policy[XFRMA_SPD_MAX+1] = {
 };
 
 static const struct xfrm_link {
-	int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **);
+	int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **,
+		    struct netlink_ext_ack *);
 	int (*start)(struct netlink_callback *);
 	int (*dump)(struct sk_buff *, struct netlink_callback *);
 	int (*done)(struct netlink_callback *);
@@ -2921,7 +3051,7 @@ static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
 		goto err;
 	}
 
-	err = link->doit(skb, nlh, attrs);
+	err = link->doit(skb, nlh, attrs, extack);
 
 	/* We need to free skb allocated in xfrm_alloc_compat() before
 	 * returning from this function, because consume_skb() won't take
@@ -3272,11 +3402,11 @@ static struct xfrm_policy *xfrm_compile_policy(struct sock *sk, int opt,
 	*dir = -EINVAL;
 
 	if (len < sizeof(*p) ||
-	    verify_newpolicy_info(p))
+	    verify_newpolicy_info(p, NULL))
 		return NULL;
 
 	nr = ((len - sizeof(*p)) / sizeof(*ut));
-	if (validate_tmpl(nr, ut, p->sel.family))
+	if (validate_tmpl(nr, ut, p->sel.family, NULL))
 		return NULL;
 
 	if (p->dir > XFRM_POLICY_OUT)

tools/testing/selftests/net/ipsec.c

@@ -58,6 +58,8 @@
 #define VETH_FMT	"ktst-%d"
 #define VETH_LEN	12
 
+#define XFRM_ALGO_NR_KEYS 29
+
 static int nsfd_parent	= -1;
 static int nsfd_childa	= -1;
 static int nsfd_childb	= -1;
@@ -75,6 +77,43 @@ const unsigned int ping_timeout		= 300;
 const unsigned int ping_count		= 100;
 const unsigned int ping_success		= 80;
 
+struct xfrm_key_entry {
+	char algo_name[35];
+	int key_len;
+};
+
+struct xfrm_key_entry xfrm_key_entries[] = {
+	{"digest_null", 0},
+	{"ecb(cipher_null)", 0},
+	{"cbc(des)", 64},
+	{"hmac(md5)", 128},
+	{"cmac(aes)", 128},
+	{"xcbc(aes)", 128},
+	{"cbc(cast5)", 128},
+	{"cbc(serpent)", 128},
+	{"hmac(sha1)", 160},
+	{"hmac(rmd160)", 160},
+	{"cbc(des3_ede)", 192},
+	{"hmac(sha256)", 256},
+	{"cbc(aes)", 256},
+	{"cbc(camellia)", 256},
+	{"cbc(twofish)", 256},
+	{"rfc3686(ctr(aes))", 288},
+	{"hmac(sha384)", 384},
+	{"cbc(blowfish)", 448},
+	{"hmac(sha512)", 512},
+	{"rfc4106(gcm(aes))-128", 160},
+	{"rfc4543(gcm(aes))-128", 160},
+	{"rfc4309(ccm(aes))-128", 152},
+	{"rfc4106(gcm(aes))-192", 224},
+	{"rfc4543(gcm(aes))-192", 224},
+	{"rfc4309(ccm(aes))-192", 216},
+	{"rfc4106(gcm(aes))-256", 288},
+	{"rfc4543(gcm(aes))-256", 288},
+	{"rfc4309(ccm(aes))-256", 280},
+	{"rfc7539(chacha20,poly1305)-128", 0}
+};
+
 static void randomize_buffer(void *buf, size_t buflen)
 {
 	int *p = (int *)buf;
@@ -767,65 +806,12 @@ static int do_ping(int cmd_fd, char *buf, size_t buf_len, struct in_addr from,
 static int xfrm_fill_key(char *name, char *buf,
 		size_t buf_len, unsigned int *key_len)
 {
-	/* TODO: use set/map instead */
-	if (strncmp(name, "digest_null", ALGO_LEN) == 0)
-		*key_len = 0;
-	else if (strncmp(name, "ecb(cipher_null)", ALGO_LEN) == 0)
-		*key_len = 0;
-	else if (strncmp(name, "cbc(des)", ALGO_LEN) == 0)
-		*key_len = 64;
-	else if (strncmp(name, "hmac(md5)", ALGO_LEN) == 0)
-		*key_len = 128;
-	else if (strncmp(name, "cmac(aes)", ALGO_LEN) == 0)
-		*key_len = 128;
-	else if (strncmp(name, "xcbc(aes)", ALGO_LEN) == 0)
-		*key_len = 128;
-	else if (strncmp(name, "cbc(cast5)", ALGO_LEN) == 0)
-		*key_len = 128;
-	else if (strncmp(name, "cbc(serpent)", ALGO_LEN) == 0)
-		*key_len = 128;
-	else if (strncmp(name, "hmac(sha1)", ALGO_LEN) == 0)
-		*key_len = 160;
-	else if (strncmp(name, "hmac(rmd160)", ALGO_LEN) == 0)
-		*key_len = 160;
-	else if (strncmp(name, "cbc(des3_ede)", ALGO_LEN) == 0)
-		*key_len = 192;
-	else if (strncmp(name, "hmac(sha256)", ALGO_LEN) == 0)
-		*key_len = 256;
-	else if (strncmp(name, "cbc(aes)", ALGO_LEN) == 0)
-		*key_len = 256;
-	else if (strncmp(name, "cbc(camellia)", ALGO_LEN) == 0)
-		*key_len = 256;
-	else if (strncmp(name, "cbc(twofish)", ALGO_LEN) == 0)
-		*key_len = 256;
-	else if (strncmp(name, "rfc3686(ctr(aes))", ALGO_LEN) == 0)
-		*key_len = 288;
-	else if (strncmp(name, "hmac(sha384)", ALGO_LEN) == 0)
-		*key_len = 384;
-	else if (strncmp(name, "cbc(blowfish)", ALGO_LEN) == 0)
-		*key_len = 448;
-	else if (strncmp(name, "hmac(sha512)", ALGO_LEN) == 0)
-		*key_len = 512;
-	else if (strncmp(name, "rfc4106(gcm(aes))-128", ALGO_LEN) == 0)
-		*key_len = 160;
-	else if (strncmp(name, "rfc4543(gcm(aes))-128", ALGO_LEN) == 0)
-		*key_len = 160;
-	else if (strncmp(name, "rfc4309(ccm(aes))-128", ALGO_LEN) == 0)
-		*key_len = 152;
-	else if (strncmp(name, "rfc4106(gcm(aes))-192", ALGO_LEN) == 0)
-		*key_len = 224;
-	else if (strncmp(name, "rfc4543(gcm(aes))-192", ALGO_LEN) == 0)
-		*key_len = 224;
-	else if (strncmp(name, "rfc4309(ccm(aes))-192", ALGO_LEN) == 0)
-		*key_len = 216;
-	else if (strncmp(name, "rfc4106(gcm(aes))-256", ALGO_LEN) == 0)
-		*key_len = 288;
-	else if (strncmp(name, "rfc4543(gcm(aes))-256", ALGO_LEN) == 0)
-		*key_len = 288;
-	else if (strncmp(name, "rfc4309(ccm(aes))-256", ALGO_LEN) == 0)
-		*key_len = 280;
-	else if (strncmp(name, "rfc7539(chacha20,poly1305)-128", ALGO_LEN) == 0)
-		*key_len = 0;
+	int i;
+
+	for (i = 0; i < XFRM_ALGO_NR_KEYS; i++) {
+		if (strncmp(name, xfrm_key_entries[i].algo_name, ALGO_LEN) == 0)
+			*key_len = xfrm_key_entries[i].key_len;
+	}
 
 	if (*key_len > buf_len) {
 		printk("Can't pack a key - too big for buffer");