---
net/ipv4/af_inet.c | 1 +
net/ipv6/af_inet6.c | 1 +
net/socket.c | 8 +++++---
3 files changed, 7 insertions(+), 3 deletions(-)
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index b7260c8cef2e..c9fd5e7cfd6e 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1052,6 +1052,7 @@ EXPORT_SYMBOL(inet_stream_ops);
const struct proto_ops inet_dgram_ops = {
.family = PF_INET,
+ .flags = PROTO_CMSG_DATA_ONLY,
.owner = THIS_MODULE,
.release = inet_release,
.bind = inet_bind,
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index e648fbebb167..560f45009d06 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -695,6 +695,7 @@ const struct proto_ops inet6_stream_ops = {
const struct proto_ops inet6_dgram_ops = {
.family = PF_INET6,
+ .flags = PROTO_CMSG_DATA_ONLY,
.owner = THIS_MODULE,
.release = inet6_release,
.bind = inet6_bind,
diff --git a/net/socket.c b/net/socket.c
index 6e6cccc2104f..6995835d6355 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -2416,9 +2416,11 @@ static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,
long __sys_sendmsg_sock(struct socket *sock, struct msghdr *msg,
unsigned int flags)
{
- /* disallow ancillary data requests from this path */
- if (msg->msg_control || msg->msg_controllen)
- return -EINVAL;
+ if (msg->msg_control || msg->msg_controllen) {
+ /* disallow ancillary data reqs unless cmsg is plain data */
+ if (!(sock->ops->flags & PROTO_CMSG_DATA_ONLY))
+ return -EINVAL;
+ }
return ____sys_sendmsg(sock, msg, flags, NULL, 0);
}
--
2.26.2
