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[net] tipc: fix potential null-ptr dereference bugs in netlink compat functions

Message ID b7fad332-e8b0-0a49-464f-7dd8bf0c8228@gmail.com
State Changes Requested, archived
Delegated to: David Miller
Headers show

Commit Message

Baozeng Ding May 22, 2016, 5:24 a.m. UTC 
Before calling the nla_parse_nested function, its third argument should be
checked to make sure it is not null. This patch fixes several potential
null pointer dereference vulnerabilities in the tipc netlink functions.

Signed-off-by: Baozeng Ding <sploving1@gmail.com>
---
 net/tipc/netlink_compat.c | 111 ++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 93 insertions(+), 18 deletions(-)
diff mbox

Patch

diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c
index 4dfc5c1..1e18b78 100644
--- a/net/tipc/netlink_compat.c
+++ b/net/tipc/netlink_compat.c
@@ -345,10 +345,16 @@  static int tipc_nl_compat_doit(struct tipc_nl_compat_cmd_doit *cmd,
 static int tipc_nl_compat_bearer_dump(struct tipc_nl_compat_msg *msg,
 				      struct nlattr **attrs)
 {
+	int err;
 	struct nlattr *bearer[TIPC_NLA_BEARER_MAX + 1];
 
-	nla_parse_nested(bearer, TIPC_NLA_BEARER_MAX, attrs[TIPC_NLA_BEARER],
-			 NULL);
+	if (!attrs[TIPC_NLA_BEARER])
+		return -EINVAL;
+
+	err = nla_parse_nested(bearer, TIPC_NLA_BEARER_MAX,
+			       attrs[TIPC_NLA_BEARER], NULL);
+	if (err)
+		return err;
 
 	return tipc_add_tlv(msg->rep, TIPC_TLV_BEARER_NAME,
 			    nla_data(bearer[TIPC_NLA_BEARER_NAME]),
@@ -456,18 +462,35 @@  static void __fill_bc_link_stat(struct tipc_nl_compat_msg *msg,
 static int tipc_nl_compat_link_stat_dump(struct tipc_nl_compat_msg *msg,
 					 struct nlattr **attrs)
 {
+	int err;
 	char *name;
 	struct nlattr *link[TIPC_NLA_LINK_MAX + 1];
 	struct nlattr *prop[TIPC_NLA_PROP_MAX + 1];
 	struct nlattr *stats[TIPC_NLA_STATS_MAX + 1];
 
-	nla_parse_nested(link, TIPC_NLA_LINK_MAX, attrs[TIPC_NLA_LINK], NULL);
+	if (!attrs[TIPC_NLA_LINK])
+		return -EINVAL;
 
-	nla_parse_nested(prop, TIPC_NLA_PROP_MAX, link[TIPC_NLA_LINK_PROP],
-			 NULL);
+	err = nla_parse_nested(link, TIPC_NLA_LINK_MAX,
+			       attrs[TIPC_NLA_LINK], NULL);
+	if (err)
+		return err;
+
+	if (!link[TIPC_NLA_LINK_PROP])
+		return -EINVAL;
 
-	nla_parse_nested(stats, TIPC_NLA_STATS_MAX, link[TIPC_NLA_LINK_STATS],
-			 NULL);
+	err = nla_parse_nested(prop, TIPC_NLA_PROP_MAX,
+			       link[TIPC_NLA_LINK_PROP], NULL);
+	if (err)
+		return err;
+
+	if (!link[TIPC_NLA_LINK_STATS])
+		return -EINVAL;
+
+	err = nla_parse_nested(stats, TIPC_NLA_STATS_MAX,
+			       link[TIPC_NLA_LINK_STATS], NULL);
+	if (err)
+		return err;
 
 	name = (char *)TLV_DATA(msg->req);
 	if (strcmp(name, nla_data(link[TIPC_NLA_LINK_NAME])) != 0)
@@ -567,10 +590,17 @@  static int tipc_nl_compat_link_stat_dump(struct tipc_nl_compat_msg *msg,
 static int tipc_nl_compat_link_dump(struct tipc_nl_compat_msg *msg,
 				    struct nlattr **attrs)
 {
+	int err;
 	struct nlattr *link[TIPC_NLA_LINK_MAX + 1];
 	struct tipc_link_info link_info;
 
-	nla_parse_nested(link, TIPC_NLA_LINK_MAX, attrs[TIPC_NLA_LINK], NULL);
+	if (!attrs[TIPC_NLA_LINK])
+		return -EINVAL;
+
+	err = nla_parse_nested(link, TIPC_NLA_LINK_MAX,
+			       attrs[TIPC_NLA_LINK], NULL);
+	if (err)
+		return err;
 
 	link_info.dest = nla_get_flag(link[TIPC_NLA_LINK_DEST]);
 	link_info.up = htonl(nla_get_flag(link[TIPC_NLA_LINK_UP]));
@@ -751,6 +781,7 @@  static int tipc_nl_compat_name_table_dump_header(struct tipc_nl_compat_msg *msg)
 static int tipc_nl_compat_name_table_dump(struct tipc_nl_compat_msg *msg,
 					  struct nlattr **attrs)
 {
+	int err;
 	char port_str[27];
 	struct tipc_name_table_query *ntq;
 	struct nlattr *nt[TIPC_NLA_NAME_TABLE_MAX + 1];
@@ -759,11 +790,21 @@  static int tipc_nl_compat_name_table_dump(struct tipc_nl_compat_msg *msg,
 	static const char * const scope_str[] = {"", " zone", " cluster",
 						 " node"};
 
-	nla_parse_nested(nt, TIPC_NLA_NAME_TABLE_MAX,
-			 attrs[TIPC_NLA_NAME_TABLE], NULL);
+	if (!attrs[TIPC_NLA_NAME_TABLE])
+		return -EINVAL;
 
-	nla_parse_nested(publ, TIPC_NLA_PUBL_MAX, nt[TIPC_NLA_NAME_TABLE_PUBL],
-			 NULL);
+	err = nla_parse_nested(nt, TIPC_NLA_NAME_TABLE_MAX,
+			       attrs[TIPC_NLA_NAME_TABLE], NULL);
+	if (err)
+		return err;
+
+	if (!nt[TIPC_NLA_NAME_TABLE_PUBL])
+		return -EINVAL;
+
+	err = nla_parse_nested(publ, TIPC_NLA_PUBL_MAX,
+			       nt[TIPC_NLA_NAME_TABLE_PUBL], NULL);
+	if (err)
+		return err;
 
 	ntq = (struct tipc_name_table_query *)TLV_DATA(msg->req);
 
@@ -813,10 +854,17 @@  out:
 static int __tipc_nl_compat_publ_dump(struct tipc_nl_compat_msg *msg,
 				      struct nlattr **attrs)
 {
+	int err;
 	u32 type, lower, upper;
 	struct nlattr *publ[TIPC_NLA_PUBL_MAX + 1];
 
-	nla_parse_nested(publ, TIPC_NLA_PUBL_MAX, attrs[TIPC_NLA_PUBL], NULL);
+	if (!attrs[TIPC_NLA_PUBL])
+		return -EINVAL;
+
+	err = nla_parse_nested(publ, TIPC_NLA_PUBL_MAX,
+			       attrs[TIPC_NLA_PUBL], NULL);
+	if (err)
+		return err;
 
 	type = nla_get_u32(publ[TIPC_NLA_PUBL_TYPE]);
 	lower = nla_get_u32(publ[TIPC_NLA_PUBL_LOWER]);
@@ -876,7 +924,13 @@  static int tipc_nl_compat_sk_dump(struct tipc_nl_compat_msg *msg,
 	u32 sock_ref;
 	struct nlattr *sock[TIPC_NLA_SOCK_MAX + 1];
 
-	nla_parse_nested(sock, TIPC_NLA_SOCK_MAX, attrs[TIPC_NLA_SOCK], NULL);
+	if (!attrs[TIPC_NLA_SOCK])
+		return -EINVAL;
+
+	err = nla_parse_nested(sock, TIPC_NLA_SOCK_MAX,
+			       attrs[TIPC_NLA_SOCK], NULL);
+	if (err)
+		return err;
 
 	sock_ref = nla_get_u32(sock[TIPC_NLA_SOCK_REF]);
 	tipc_tlv_sprintf(msg->rep, "%u:", sock_ref);
@@ -916,10 +970,16 @@  static int tipc_nl_compat_sk_dump(struct tipc_nl_compat_msg *msg,
 static int tipc_nl_compat_media_dump(struct tipc_nl_compat_msg *msg,
 				     struct nlattr **attrs)
 {
+	int err;
 	struct nlattr *media[TIPC_NLA_MEDIA_MAX + 1];
 
-	nla_parse_nested(media, TIPC_NLA_MEDIA_MAX, attrs[TIPC_NLA_MEDIA],
-			 NULL);
+	if (!attrs[TIPC_NLA_MEDIA])
+		return -EINVAL;
+
+	err = nla_parse_nested(media, TIPC_NLA_MEDIA_MAX, attrs[TIPC_NLA_MEDIA],
+			       NULL);
+	if (err)
+		return err;
 
 	return tipc_add_tlv(msg->rep, TIPC_TLV_MEDIA_NAME,
 			    nla_data(media[TIPC_NLA_MEDIA_NAME]),
@@ -929,10 +989,17 @@  static int tipc_nl_compat_media_dump(struct tipc_nl_compat_msg *msg,
 static int tipc_nl_compat_node_dump(struct tipc_nl_compat_msg *msg,
 				    struct nlattr **attrs)
 {
+	int err;
 	struct tipc_node_info node_info;
 	struct nlattr *node[TIPC_NLA_NODE_MAX + 1];
 
-	nla_parse_nested(node, TIPC_NLA_NODE_MAX, attrs[TIPC_NLA_NODE], NULL);
+	if (!attrs[TIPC_NLA_NODE])
+		return -EINVAL;
+
+	err = nla_parse_nested(node, TIPC_NLA_NODE_MAX,
+			       attrs[TIPC_NLA_NODE], NULL);
+	if (err)
+		return err;
 
 	node_info.addr = htonl(nla_get_u32(node[TIPC_NLA_NODE_ADDR]));
 	node_info.up = htonl(nla_get_flag(node[TIPC_NLA_NODE_UP]));
@@ -969,10 +1036,18 @@  static int tipc_nl_compat_net_set(struct tipc_nl_compat_cmd_doit *cmd,
 static int tipc_nl_compat_net_dump(struct tipc_nl_compat_msg *msg,
 				   struct nlattr **attrs)
 {
+	int err;
 	__be32 id;
 	struct nlattr *net[TIPC_NLA_NET_MAX + 1];
 
-	nla_parse_nested(net, TIPC_NLA_NET_MAX, attrs[TIPC_NLA_NET], NULL);
+	if (!attrs[TIPC_NLA_NET])
+		return -EINVAL;
+
+	err = nla_parse_nested(net, TIPC_NLA_NET_MAX,
+			       attrs[TIPC_NLA_NET], NULL);
+	if (err)
+		return err;
+
 	id = htonl(nla_get_u32(net[TIPC_NLA_NET_ID]));
 
 	return tipc_add_tlv(msg->rep, TIPC_TLV_UNSIGNED, &id, sizeof(id));