X-Git-Url: http://git.cascardo.info/?p=cascardo%2Flinux.git;a=blobdiff_plain;f=drivers%2Fnet%2Ftun.c;h=c0df872f5b8c53818ca7b7c130f1fcb0fb972e89;hp=a5cbf67517f09e08e728a44dd9917e2792d37d9d;hb=64bb1b944b554a751b518b09c3d596f6b6c0ce31;hpb=67e2c3883828b39548cee2091b36656787775d95

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index a5cbf67517f0..c0df872f5b8c 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -110,9 +110,11 @@ do {								\
  * overload it to mean fasync when stored there.
  */
 #define TUN_FASYNC	IFF_ATTACH_QUEUE
+/* High bits in flags field are unused. */
+#define TUN_VNET_LE     0x80000000
 
 #define TUN_FEATURES (IFF_NO_PI | IFF_ONE_QUEUE | IFF_VNET_HDR | \
-		      IFF_VNET_LE | IFF_MULTI_QUEUE)
+		      IFF_MULTI_QUEUE)
 #define GOODCOPY_LEN 128
 
 #define FLT_EXACT_COUNT 8
@@ -208,12 +210,12 @@ struct tun_struct {
 
 static inline u16 tun16_to_cpu(struct tun_struct *tun, __virtio16 val)
 {
-	return __virtio16_to_cpu(tun->flags & IFF_VNET_LE, val);
+	return __virtio16_to_cpu(tun->flags & TUN_VNET_LE, val);
 }
 
 static inline __virtio16 cpu_to_tun16(struct tun_struct *tun, u16 val)
 {
-	return __cpu_to_virtio16(tun->flags & IFF_VNET_LE, val);
+	return __cpu_to_virtio16(tun->flags & TUN_VNET_LE, val);
 }
 
 static inline u32 tun_hashfn(u32 rxhash)
@@ -1378,7 +1380,7 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile,
 	skb = __skb_recv_datagram(tfile->socket.sk, noblock ? MSG_DONTWAIT : 0,
 				  &peeked, &off, &err);
 	if (!skb)
-		return 0;
+		return err;
 
 	ret = tun_put_user(tun, tfile, skb, to);
 	if (unlikely(ret < 0))
@@ -1499,7 +1501,7 @@ static int tun_recvmsg(struct kiocb *iocb, struct socket *sock,
 		goto out;
 	}
 	ret = tun_do_read(tun, tfile, &m->msg_iter, flags & MSG_DONTWAIT);
-	if (ret > total_len) {
+	if (ret > (ssize_t)total_len) {
 		m->msg_flags |= MSG_TRUNC;
 		ret = flags & MSG_TRUNC ? ret : total_len;
 	}
@@ -1843,6 +1845,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
 	int sndbuf;
 	int vnet_hdr_sz;
 	unsigned int ifindex;
+	int le;
 	int ret;
 
 	if (cmd == TUNSETIFF || cmd == TUNSETQUEUE || _IOC_TYPE(cmd) == 0x89) {
@@ -2042,6 +2045,23 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
 		tun->vnet_hdr_sz = vnet_hdr_sz;
 		break;
 
+	case TUNGETVNETLE:
+		le = !!(tun->flags & TUN_VNET_LE);
+		if (put_user(le, (int __user *)argp))
+			ret = -EFAULT;
+		break;
+
+	case TUNSETVNETLE:
+		if (get_user(le, (int __user *)argp)) {
+			ret = -EFAULT;
+			break;
+		}
+		if (le)
+			tun->flags |= TUN_VNET_LE;
+		else
+			tun->flags &= ~TUN_VNET_LE;
+		break;
+
 	case TUNATTACHFILTER:
 		/* Can be set only for TAPs */
 		ret = -EINVAL;