[PATCH 3.17 33/47] net-timestamp: make tcp_recvmsg call ipv6_recv_error for AF_INET6 socks

Greg Kroah-Hartman
2014-12-14T20:29:17Z

From: Willem de Bruijn <willemb@google.com>

[ Upstream commit f4713a3dfad045d46afcb9c2a7d0bba288920ed4 ]

TCP timestamping introduced MSG_ERRQUEUE handling for TCP sockets.
If the socket is of family AF_INET6, call ipv6_recv_error instead
of ip_recv_error.

This change is more complex than a single branch due to the loadable
ipv6 module. It reuses a pre-existing indirect function call from
ping. The ping code is safe to call, because it is part of the core
ipv6 module and always present when AF_INET6 sockets are active.

Fixes: 4ed2d765 (net-timestamp: TCP timestamping)
Signed-off-by: Willem de Bruijn <willemb@google.com>

----

It may also be worthwhile to add WARN_ON_ONCE(sk->family == AF_INET6)
to ip_recv_error.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/net/inet_common.h | 2 ++
net/ipv4/af_inet.c | 11 +++++++++++
net/ipv4/ping.c | 12 ++----------
net/ipv4/tcp.c | 2 +-
4 files changed, 16 insertions(+), 11 deletions(-)

--- a/include/net/inet_common.h
+++ b/include/net/inet_common.h
@@ -37,6 +37,8 @@ int inet_ioctl(struct socket *sock, unsi
int inet_ctl_sock_create(struct sock **sk, unsigned short family,
unsigned short type, unsigned char protocol,
struct net *net);
+int inet_recv_error(struct sock *sk, struct msghdr *msg, int len,
+ int *addr_len);

static inline void inet_ctl_sock_destroy(struct sock *sk)
{
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1421,6 +1421,17 @@ out:
return pp;
}

+int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
+{
+ if (sk->sk_family == AF_INET)
+ return ip_recv_error(sk, msg, len, addr_len);
+#if IS_ENABLED(CONFIG_IPV6)
+ if (sk->sk_family == AF_INET6)
+ return pingv6_ops.ipv6_recv_error(sk, msg, len, addr_len);
+#endif
+ return -EINVAL;
+}
+
static int inet_gro_complete(struct sk_buff *skb, int nhoff)
{
__be16 newlen = htons(skb->len - nhoff);
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -855,16 +855,8 @@ int ping_recvmsg(struct kiocb *iocb, str
if (flags & MSG_OOB)
goto out;

- if (flags & MSG_ERRQUEUE) {
- if (family == AF_INET) {
- return ip_recv_error(sk, msg, len, addr_len);
-#if IS_ENABLED(CONFIG_IPV6)
- } else if (family == AF_INET6) {
- return pingv6_ops.ipv6_recv_error(sk, msg, len,
- addr_len);
-#endif
- }
- }
+ if (flags & MSG_ERRQUEUE)
+ return inet_recv_error(sk, msg, len, addr_len);

skb = skb_recv_datagram(sk, flags, noblock, &err);
if (!skb)
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1633,7 +1633,7 @@ int tcp_recvmsg(struct kiocb *iocb, stru
u32 urg_hole = 0;

if (unlikely(flags & MSG_ERRQUEUE))
- return ip_recv_error(sk, msg, len, addr_len);
+ return inet_recv_error(sk, msg, len, addr_len);

if (sk_can_busy_loop(sk) && skb_queue_empty(&sk->sk_receive_queue) &&
(sk->sk_state == TCP_ESTABLISHED))