1 files changed, 49 insertions, 1 deletions

diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c
index f86c6555a539..e9653c42cdd1 100644
--- a/net/tipc/netlink_compat.c
+++ b/net/tipc/netlink_compat.c
@@ -87,6 +87,11 @@ static int tipc_skb_tailroom(struct sk_buff *skb)
 	return limit;
 }
 
+static inline int TLV_GET_DATA_LEN(struct tlv_desc *tlv)
+{
+	return TLV_GET_LEN(tlv) - TLV_SPACE(0);
+}
+
 static int tipc_add_tlv(struct sk_buff *skb, u16 type, void *data, u16 len)
 {
 	struct tlv_desc *tlv = (struct tlv_desc *)skb_tail_pointer(skb);
@@ -166,6 +171,11 @@ static struct sk_buff *tipc_get_err_tlv(char *str)
 	return buf;
 }
 
+static inline bool string_is_valid(char *s, int len)
+{
+	return memchr(s, '\0', len) ? true : false;
+}
+
 static int __tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd,
 				   struct tipc_nl_compat_msg *msg,
 				   struct sk_buff *arg)
@@ -364,6 +374,7 @@ static int tipc_nl_compat_bearer_enable(struct tipc_nl_compat_cmd_doit *cmd,
 	struct nlattr *prop;
 	struct nlattr *bearer;
 	struct tipc_bearer_config *b;
+	int len;
 
 	b = (struct tipc_bearer_config *)TLV_DATA(msg->req);
 
@@ -371,6 +382,10 @@ static int tipc_nl_compat_bearer_enable(struct tipc_nl_compat_cmd_doit *cmd,
 	if (!bearer)
 		return -EMSGSIZE;
 
+	len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_BEARER_NAME);
+	if (!string_is_valid(b->name, len))
+		return -EINVAL;
+
 	if (nla_put_string(skb, TIPC_NLA_BEARER_NAME, b->name))
 		return -EMSGSIZE;
 
@@ -396,6 +411,7 @@ static int tipc_nl_compat_bearer_disable(struct tipc_nl_compat_cmd_doit *cmd,
 {
 	char *name;
 	struct nlattr *bearer;
+	int len;
 
 	name = (char *)TLV_DATA(msg->req);
 
@@ -403,6 +419,10 @@ static int tipc_nl_compat_bearer_disable(struct tipc_nl_compat_cmd_doit *cmd,
 	if (!bearer)
 		return -EMSGSIZE;
 
+	len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_BEARER_NAME);
+	if (!string_is_valid(name, len))
+		return -EINVAL;
+
 	if (nla_put_string(skb, TIPC_NLA_BEARER_NAME, name))
 		return -EMSGSIZE;
 
@@ -462,6 +482,7 @@ static int tipc_nl_compat_link_stat_dump(struct tipc_nl_compat_msg *msg,
 	struct nlattr *link[TIPC_NLA_LINK_MAX + 1];
 	struct nlattr *prop[TIPC_NLA_PROP_MAX + 1];
 	struct nlattr *stats[TIPC_NLA_STATS_MAX + 1];
+	int len;
 
 	nla_parse_nested(link, TIPC_NLA_LINK_MAX, attrs[TIPC_NLA_LINK], NULL);
 
@@ -472,6 +493,11 @@ static int tipc_nl_compat_link_stat_dump(struct tipc_nl_compat_msg *msg,
 			 NULL);
 
 	name = (char *)TLV_DATA(msg->req);
+
+	len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_LINK_NAME);
+	if (!string_is_valid(name, len))
+		return -EINVAL;
+
 	if (strcmp(name, nla_data(link[TIPC_NLA_LINK_NAME])) != 0)
 		return 0;
 
@@ -605,6 +631,7 @@ static int tipc_nl_compat_media_set(struct sk_buff *skb,
 	struct nlattr *prop;
 	struct nlattr *media;
 	struct tipc_link_config *lc;
+	int len;
 
 	lc = (struct tipc_link_config *)TLV_DATA(msg->req);
 
@@ -612,6 +639,10 @@ static int tipc_nl_compat_media_set(struct sk_buff *skb,
 	if (!media)
 		return -EMSGSIZE;
 
+	len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_MEDIA_NAME);
+	if (!string_is_valid(lc->name, len))
+		return -EINVAL;
+
 	if (nla_put_string(skb, TIPC_NLA_MEDIA_NAME, lc->name))
 		return -EMSGSIZE;
 
@@ -632,6 +663,7 @@ static int tipc_nl_compat_bearer_set(struct sk_buff *skb,
 	struct nlattr *prop;
 	struct nlattr *bearer;
 	struct tipc_link_config *lc;
+	int len;
 
 	lc = (struct tipc_link_config *)TLV_DATA(msg->req);
 
@@ -639,6 +671,10 @@ static int tipc_nl_compat_bearer_set(struct sk_buff *skb,
 	if (!bearer)
 		return -EMSGSIZE;
 
+	len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_MEDIA_NAME);
+	if (!string_is_valid(lc->name, len))
+		return -EINVAL;
+
 	if (nla_put_string(skb, TIPC_NLA_BEARER_NAME, lc->name))
 		return -EMSGSIZE;
 
@@ -687,9 +723,14 @@ static int tipc_nl_compat_link_set(struct tipc_nl_compat_cmd_doit *cmd,
 	struct tipc_link_config *lc;
 	struct tipc_bearer *bearer;
 	struct tipc_media *media;
+	int len;
 
 	lc = (struct tipc_link_config *)TLV_DATA(msg->req);
 
+	len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_LINK_NAME);
+	if (!string_is_valid(lc->name, len))
+		return -EINVAL;
+
 	media = tipc_media_find(lc->name);
 	if (media) {
 		cmd->doit = &tipc_nl_media_set;
@@ -711,6 +752,7 @@ static int tipc_nl_compat_link_reset_stats(struct tipc_nl_compat_cmd_doit *cmd,
 {
 	char *name;
 	struct nlattr *link;
+	int len;
 
 	name = (char *)TLV_DATA(msg->req);
 
@@ -718,6 +760,10 @@ static int tipc_nl_compat_link_reset_stats(struct tipc_nl_compat_cmd_doit *cmd,
 	if (!link)
 		return -EMSGSIZE;
 
+	len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_LINK_NAME);
+	if (!string_is_valid(name, len))
+		return -EINVAL;
+
 	if (nla_put_string(skb, TIPC_NLA_LINK_NAME, name))
 		return -EMSGSIZE;
 
@@ -739,6 +785,8 @@ static int tipc_nl_compat_name_table_dump_header(struct tipc_nl_compat_msg *msg)
 	};
 
 	ntq = (struct tipc_name_table_query *)TLV_DATA(msg->req);
+	if (TLV_GET_DATA_LEN(msg->req) < sizeof(struct tipc_name_table_query))
+		return -EINVAL;
 
 	depth = ntohl(ntq->depth);
 
@@ -1117,7 +1165,7 @@ static int tipc_nl_compat_recv(struct sk_buff *skb, struct genl_info *info)
 	}
 
 	len = nlmsg_attrlen(req_nlh, GENL_HDRLEN + TIPC_GENL_HDRLEN);
-	if (len && !TLV_OK(msg.req, len)) {
+	if (!len || !TLV_OK(msg.req, len)) {
 		msg.rep = tipc_get_err_tlv(TIPC_CFG_NOT_SUPPORTED);
 		err = -EOPNOTSUPP;
 		goto send;