[PATCH 25/33] ipv6: add ip6_sock_set_v6only

Christoph Hellwig
2020-05-20T19:56:58Z

Add a helper to directly set the IPV6_V6ONLY sockopt from kernel space
without going through a fake uaccess.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
include/net/ipv6.h | 11 +++++++++++
net/ipv6/ip6_udp_tunnel.c | 5 +----
net/sunrpc/svcsock.c | 6 +-----
3 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 5fc3a9d7b053e..7d1cb9f0f5388 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -1176,4 +1176,15 @@ int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
const struct in6_addr *addr, unsigned int mode);
int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
const struct in6_addr *addr);
+
+static inline int ip6_sock_set_v6only(struct sock *sk)
+{
+ if (inet_sk(sk)->inet_num)
+ return -EINVAL;
+ lock_sock(sk);
+ sk->sk_ipv6only = true;
+ release_sock(sk);
+ return 0;
+}
+
#endif /* _NET_IPV6_H */
diff --git a/net/ipv6/ip6_udp_tunnel.c b/net/ipv6/ip6_udp_tunnel.c
index 6523609516d25..2e0ad1bc84a83 100644
--- a/net/ipv6/ip6_udp_tunnel.c
+++ b/net/ipv6/ip6_udp_tunnel.c
@@ -25,10 +25,7 @@ int udp_sock_create6(struct net *net, struct udp_port_cfg *cfg,
goto error;

if (cfg->ipv6_v6only) {
- int val = 1;
-
- err = kernel_setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY,
- (char *) &val, sizeof(val));
+ err = ip6_sock_set_v6only(sock->sk);
if (err < 0)
goto error;
}
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 7a805d165689c..a391892977cd2 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -1328,7 +1328,6 @@ static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
struct sockaddr *newsin = (struct sockaddr *)&addr;
int newlen;
int family;
- int val;
RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);

dprintk("svc: svc_create_socket(%s, %d, %s)\n",
@@ -1364,11 +1363,8 @@ static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
* getting requests from IPv4 remotes. Those should
* be shunted to a PF_INET listener via rpcbind.
*/
- val = 1;
if (family == PF_INET6)
- kernel_setsockopt(sock, SOL_IPV6, IPV6_V6ONLY,
- (char *)&val, sizeof(val));
-
+ ip6_sock_set_v6only(sock->sk);
if (type == SOCK_STREAM)
sock->sk->sk_reuse = SK_CAN_REUSE; /* allow address reuse */
error = kernel_bind(sock, sin, len);
--
2.26.2