tipc: add extack messages for bearer/media failure

stable inclusion
from stable-5.10.43
commit e31ae45ed1d323b4409c3575299f6c203f0b3d2a
bugzilla: 109284
CVE: NA

--------------------------------

[ Upstream commit b83e214b ]

Add extack error messages for -EINVAL errors when enabling bearer,
getting/setting properties for a media/bearer
Acked-by: NJon Maloy <jmaloy@redhat.com>
Signed-off-by: NHoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

net/tipc/bearer.c

@@ -234,7 +234,8 @@ void tipc_bearer_remove_dest(struct net *net, u32 bearer_id, u32 dest)
  */
 static int tipc_enable_bearer(struct net *net, const char *name,
 			      u32 disc_domain, u32 prio,
-			      struct nlattr *attr[])
+			      struct nlattr *attr[],
+			      struct netlink_ext_ack *extack)
 {
 	struct tipc_net *tn = tipc_net(net);
 	struct tipc_bearer_names b_names;
@@ -248,17 +249,20 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 
 	if (!bearer_name_validate(name, &b_names)) {
 		errstr = "illegal name";
+		NL_SET_ERR_MSG(extack, "Illegal name");
 		goto rejected;
 	}
 
 	if (prio > TIPC_MAX_LINK_PRI && prio != TIPC_MEDIA_LINK_PRI) {
 		errstr = "illegal priority";
+		NL_SET_ERR_MSG(extack, "Illegal priority");
 		goto rejected;
 	}
 
 	m = tipc_media_find(b_names.media_name);
 	if (!m) {
 		errstr = "media not registered";
+		NL_SET_ERR_MSG(extack, "Media not registered");
 		goto rejected;
 	}
 
@@ -272,6 +276,7 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 			break;
 		if (!strcmp(name, b->name)) {
 			errstr = "already enabled";
+			NL_SET_ERR_MSG(extack, "Already enabled");
 			goto rejected;
 		}
 		bearer_id++;
@@ -283,6 +288,7 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 			name, prio);
 		if (prio == TIPC_MIN_LINK_PRI) {
 			errstr = "cannot adjust to lower";
+			NL_SET_ERR_MSG(extack, "Cannot adjust to lower");
 			goto rejected;
 		}
 		pr_warn("Bearer <%s>: trying with adjusted priority\n", name);
@@ -293,6 +299,7 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 
 	if (bearer_id >= MAX_BEARERS) {
 		errstr = "max 3 bearers permitted";
+		NL_SET_ERR_MSG(extack, "Max 3 bearers permitted");
 		goto rejected;
 	}
 
@@ -306,6 +313,7 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 	if (res) {
 		kfree(b);
 		errstr = "failed to enable media";
+		NL_SET_ERR_MSG(extack, "Failed to enable media");
 		goto rejected;
 	}
 
@@ -322,6 +330,7 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 	if (res) {
 		bearer_disable(net, b);
 		errstr = "failed to create discoverer";
+		NL_SET_ERR_MSG(extack, "Failed to create discoverer");
 		goto rejected;
 	}
 
@@ -894,6 +903,7 @@ int tipc_nl_bearer_get(struct sk_buff *skb, struct genl_info *info)
 	bearer = tipc_bearer_find(net, name);
 	if (!bearer) {
 		err = -EINVAL;
+		NL_SET_ERR_MSG(info->extack, "Bearer not found");
 		goto err_out;
 	}
 
@@ -933,8 +943,10 @@ int __tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info)
 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
 
 	bearer = tipc_bearer_find(net, name);
-	if (!bearer)
+	if (!bearer) {
+		NL_SET_ERR_MSG(info->extack, "Bearer not found");
 		return -EINVAL;
+	}
 
 	bearer_disable(net, bearer);
 
@@ -992,7 +1004,8 @@ int __tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
 	}
 
-	return tipc_enable_bearer(net, bearer, domain, prio, attrs);
+	return tipc_enable_bearer(net, bearer, domain, prio, attrs,
+				  info->extack);
 }
 
 int tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
@@ -1031,6 +1044,7 @@ int tipc_nl_bearer_add(struct sk_buff *skb, struct genl_info *info)
 	b = tipc_bearer_find(net, name);
 	if (!b) {
 		rtnl_unlock();
+		NL_SET_ERR_MSG(info->extack, "Bearer not found");
 		return -EINVAL;
 	}
 
@@ -1071,8 +1085,10 @@ int __tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
 
 	b = tipc_bearer_find(net, name);
-	if (!b)
+	if (!b) {
+		NL_SET_ERR_MSG(info->extack, "Bearer not found");
 		return -EINVAL;
+	}
 
 	if (attrs[TIPC_NLA_BEARER_PROP]) {
 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
@@ -1091,12 +1107,18 @@ int __tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
 		if (props[TIPC_NLA_PROP_WIN])
 			b->max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
 		if (props[TIPC_NLA_PROP_MTU]) {
-			if (b->media->type_id != TIPC_MEDIA_TYPE_UDP)
+			if (b->media->type_id != TIPC_MEDIA_TYPE_UDP) {
+				NL_SET_ERR_MSG(info->extack,
+					       "MTU property is unsupported");
 				return -EINVAL;
+			}
 #ifdef CONFIG_TIPC_MEDIA_UDP
 			if (tipc_udp_mtu_bad(nla_get_u32
-					     (props[TIPC_NLA_PROP_MTU])))
+					     (props[TIPC_NLA_PROP_MTU]))) {
+				NL_SET_ERR_MSG(info->extack,
+					       "MTU value is out-of-range");
 				return -EINVAL;
+			}
 			b->mtu = nla_get_u32(props[TIPC_NLA_PROP_MTU]);
 			tipc_node_apply_property(net, b, TIPC_NLA_PROP_MTU);
 #endif
@@ -1224,6 +1246,7 @@ int tipc_nl_media_get(struct sk_buff *skb, struct genl_info *info)
 	rtnl_lock();
 	media = tipc_media_find(name);
 	if (!media) {
+		NL_SET_ERR_MSG(info->extack, "Media not found");
 		err = -EINVAL;
 		goto err_out;
 	}
@@ -1260,9 +1283,10 @@ int __tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
 	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);
 
 	m = tipc_media_find(name);
-	if (!m)
+	if (!m) {
+		NL_SET_ERR_MSG(info->extack, "Media not found");
 		return -EINVAL;
-
+	}
 	if (attrs[TIPC_NLA_MEDIA_PROP]) {
 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
 
@@ -1278,12 +1302,18 @@ int __tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
 		if (props[TIPC_NLA_PROP_WIN])
 			m->max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
 		if (props[TIPC_NLA_PROP_MTU]) {
-			if (m->type_id != TIPC_MEDIA_TYPE_UDP)
+			if (m->type_id != TIPC_MEDIA_TYPE_UDP) {
+				NL_SET_ERR_MSG(info->extack,
+					       "MTU property is unsupported");
 				return -EINVAL;
+			}
 #ifdef CONFIG_TIPC_MEDIA_UDP
 			if (tipc_udp_mtu_bad(nla_get_u32
-					     (props[TIPC_NLA_PROP_MTU])))
+					     (props[TIPC_NLA_PROP_MTU]))) {
+				NL_SET_ERR_MSG(info->extack,
+					       "MTU value is out-of-range");
 				return -EINVAL;
+			}
 			m->mtu = nla_get_u32(props[TIPC_NLA_PROP_MTU]);
 #endif
 		}