net: rework SIOCGSTAMP ioctl handling

The SIOCGSTAMP/SIOCGSTAMPNS ioctl commands are implemented by many
socket protocol handlers, and all of those end up calling the same
sock_get_timestamp()/sock_get_timestampns() helper functions, which
results in a lot of duplicate code.

With the introduction of 64-bit time_t on 32-bit architectures, this
gets worse, as we then need four different ioctl commands in each
socket protocol implementation.

To simplify that, let's add a new .gettstamp() operation in
struct proto_ops, and move ioctl implementation into the common
sock_ioctl()/compat_sock_ioctl_trans() functions that these all go
through.

We can reuse the sock_get_timestamp() implementation, but generalize
it so it can deal with both native and compat mode, as well as
timeval and timespec structures.

Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/lkml/CAK8P3a038aDQQotzua_QtKGhq8O9n+rdiz2=WDCp82ys8eUT+A@mail.gmail.com/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 34 deletions

diff --git a/net/socket.c b/net/socket.c
index 8255f5bda0aa..ab624d42ead5 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -1164,6 +1164,15 @@ static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 
 			err = open_related_ns(&net->ns, get_net_ns);
 			break;
+		case SIOCGSTAMP:
+		case SIOCGSTAMPNS:
+			if (!sock->ops->gettstamp) {
+				err = -ENOIOCTLCMD;
+				break;
+			}
+			err = sock->ops->gettstamp(sock, argp,
+						   cmd == SIOCGSTAMP, false);
+			break;
 		default:
 			err = sock_do_ioctl(net, sock, cmd, arg);
 			break;
@@ -2916,38 +2925,6 @@ void socket_seq_show(struct seq_file *seq)
 #endif				/* CONFIG_PROC_FS */
 
 #ifdef CONFIG_COMPAT
-static int do_siocgstamp(struct net *net, struct socket *sock,
-			 unsigned int cmd, void __user *up)
-{
-	mm_segment_t old_fs = get_fs();
-	struct timeval ktv;
-	int err;
-
-	set_fs(KERNEL_DS);
-	err = sock_do_ioctl(net, sock, cmd, (unsigned long)&ktv);
-	set_fs(old_fs);
-	if (!err)
-		err = compat_put_timeval(&ktv, up);
-
-	return err;
-}
-
-static int do_siocgstampns(struct net *net, struct socket *sock,
-			   unsigned int cmd, void __user *up)
-{
-	mm_segment_t old_fs = get_fs();
-	struct timespec kts;
-	int err;
-
-	set_fs(KERNEL_DS);
-	err = sock_do_ioctl(net, sock, cmd, (unsigned long)&kts);
-	set_fs(old_fs);
-	if (!err)
-		err = compat_put_timespec(&kts, up);
-
-	return err;
-}
-
 static int compat_dev_ifconf(struct net *net, struct compat_ifconf __user *uifc32)
 {
 	struct compat_ifconf ifc32;
@@ -3348,9 +3325,12 @@ static int compat_sock_ioctl_trans(struct file *file, struct socket *sock,
 	case SIOCDELRT:
 		return routing_ioctl(net, sock, cmd, argp);
 	case SIOCGSTAMP:
-		return do_siocgstamp(net, sock, cmd, argp);
 	case SIOCGSTAMPNS:
-		return do_siocgstampns(net, sock, cmd, argp);
+		if (!sock->ops->gettstamp)
+			return -ENOIOCTLCMD;
+		return sock->ops->gettstamp(sock, argp, cmd == SIOCGSTAMP,
+					    !COMPAT_USE_64BIT_TIME);
+
 	case SIOCBONDSLAVEINFOQUERY:
 	case SIOCBONDINFOQUERY:
 	case SIOCSHWTSTAMP: