net: add build-time checks for msg->msg_name size
This is a follow-up patch to f3d3342602f8bc ("net: rework recvmsg
handler msg_name and msg_namelen logic").
DECLARE_SOCKADDR validates that the structure we use for writing the
name information to is not larger than the buffer which is reserved
for msg->msg_name (which is 128 bytes). Also use DECLARE_SOCKADDR
consistently in sendmsg code paths.
Signed-off-by: Steffen Hurrle <steffen@hurrle.net>
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c
index 29487a8..aab5f74 100644
--- a/net/l2tp/l2tp_ip6.c
+++ b/net/l2tp/l2tp_ip6.c
@@ -481,8 +481,7 @@
struct msghdr *msg, size_t len)
{
struct ipv6_txoptions opt_space;
- struct sockaddr_l2tpip6 *lsa =
- (struct sockaddr_l2tpip6 *) msg->msg_name;
+ DECLARE_SOCKADDR(struct sockaddr_l2tpip6 *, lsa, msg->msg_name);
struct in6_addr *daddr, *final_p, final;
struct ipv6_pinfo *np = inet6_sk(sk);
struct ipv6_txoptions *opt = NULL;
@@ -652,7 +651,7 @@
int flags, int *addr_len)
{
struct ipv6_pinfo *np = inet6_sk(sk);
- struct sockaddr_l2tpip6 *lsa = (struct sockaddr_l2tpip6 *)msg->msg_name;
+ DECLARE_SOCKADDR(struct sockaddr_l2tpip6 *, lsa, msg->msg_name);
size_t copied = 0;
int err = -EOPNOTSUPP;
struct sk_buff *skb;