[PATCH 145/150] rtnetlink: Mask the rta_type when range checking

[Luis Henriques]

3.5.7.9 -stable review patch.  If anyone has any objections, please let me know.

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

From: Vlad Yasevich <vyasevic at redhat.com>

commit a5b8db91442fce9c9713fcd656c3698f1adde1d6 upstream.

Range/validity checks on rta_type in rtnetlink_rcv_msg() do
not account for flags that may be set.  This causes the function
to return -EINVAL when flags are set on the type (for example
NLA_F_NESTED).

Signed-off-by: Vlad Yasevich <vyasevic at redhat.com>
Acked-by: Thomas Graf <tgraf at suug.ch>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 net/core/rtnetlink.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 8f37bec..844ccc6 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -2317,7 +2317,7 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		struct rtattr *attr = (void *)nlh + NLMSG_ALIGN(min_len);
 
 		while (RTA_OK(attr, attrlen)) {
-			unsigned int flavor = attr->rta_type;
+			unsigned int flavor = attr->rta_type & NLA_TYPE_MASK;
 			if (flavor) {
 				if (flavor > rta_max[sz_idx])
 					return -EINVAL;
-- 
1.8.1.2