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/can/raw.c b/net/can/raw.c
index 641e1c8..07d72d8 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -675,8 +675,7 @@
int err;
if (msg->msg_name) {
- struct sockaddr_can *addr =
- (struct sockaddr_can *)msg->msg_name;
+ DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
if (msg->msg_namelen < sizeof(*addr))
return -EINVAL;
@@ -775,6 +774,7 @@
sock_recv_ts_and_drops(msg, sk, skb);
if (msg->msg_name) {
+ __sockaddr_check_size(sizeof(struct sockaddr_can));
msg->msg_namelen = sizeof(struct sockaddr_can);
memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
}