userns: Convert tun/tap to use kuid and kgid where appropriate
Cc: Maxim Krasnyansky <maxk@qualcomm.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 926d4db..a9bd9f3 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -120,8 +120,8 @@
struct tun_struct {
struct tun_file *tfile;
unsigned int flags;
- uid_t owner;
- gid_t group;
+ kuid_t owner;
+ kgid_t group;
struct net_device *dev;
netdev_features_t set_features;
@@ -1032,8 +1032,8 @@
{
struct tun_struct *tun = netdev_priv(dev);
- tun->owner = -1;
- tun->group = -1;
+ tun->owner = INVALID_UID;
+ tun->group = INVALID_GID;
dev->ethtool_ops = &tun_ethtool_ops;
dev->destructor = tun_free_netdev;
@@ -1156,14 +1156,20 @@
char *buf)
{
struct tun_struct *tun = netdev_priv(to_net_dev(dev));
- return sprintf(buf, "%d\n", tun->owner);
+ return uid_valid(tun->owner)?
+ sprintf(buf, "%u\n",
+ from_kuid_munged(current_user_ns(), tun->owner)):
+ sprintf(buf, "-1\n");
}
static ssize_t tun_show_group(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tun_struct *tun = netdev_priv(to_net_dev(dev));
- return sprintf(buf, "%d\n", tun->group);
+ return gid_valid(tun->group) ?
+ sprintf(buf, "%u\n",
+ from_kgid_munged(current_user_ns(), tun->group)):
+ sprintf(buf, "-1\n");
}
static DEVICE_ATTR(tun_flags, 0444, tun_show_flags, NULL);
@@ -1190,8 +1196,8 @@
else
return -EINVAL;
- if (((tun->owner != -1 && cred->euid != tun->owner) ||
- (tun->group != -1 && !in_egroup_p(tun->group))) &&
+ if (((uid_valid(tun->owner) && !uid_eq(cred->euid, tun->owner)) ||
+ (gid_valid(tun->group) && !in_egroup_p(tun->group))) &&
!capable(CAP_NET_ADMIN))
return -EPERM;
err = security_tun_dev_attach(tun->socket.sk);
@@ -1375,6 +1381,8 @@
void __user* argp = (void __user*)arg;
struct sock_fprog fprog;
struct ifreq ifr;
+ kuid_t owner;
+ kgid_t group;
int sndbuf;
int vnet_hdr_sz;
int ret;
@@ -1448,16 +1456,26 @@
case TUNSETOWNER:
/* Set owner of the device */
- tun->owner = (uid_t) arg;
-
- tun_debug(KERN_INFO, tun, "owner set to %d\n", tun->owner);
+ owner = make_kuid(current_user_ns(), arg);
+ if (!uid_valid(owner)) {
+ ret = -EINVAL;
+ break;
+ }
+ tun->owner = owner;
+ tun_debug(KERN_INFO, tun, "owner set to %d\n",
+ from_kuid(&init_user_ns, tun->owner));
break;
case TUNSETGROUP:
/* Set group of the device */
- tun->group= (gid_t) arg;
-
- tun_debug(KERN_INFO, tun, "group set to %d\n", tun->group);
+ group = make_kgid(current_user_ns(), arg);
+ if (!gid_valid(group)) {
+ ret = -EINVAL;
+ break;
+ }
+ tun->group = group;
+ tun_debug(KERN_INFO, tun, "group set to %d\n",
+ from_kgid(&init_user_ns, tun->group));
break;
case TUNSETLINK:
diff --git a/init/Kconfig b/init/Kconfig
index eac23a6f..b445d6f 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1003,7 +1003,6 @@
depends on !UML || HOSTFS = n
# The rare drivers that won't build
- depends on TUN = n
depends on INFINIBAND_QIB = n
depends on BLK_DEV_LOOP = n
depends on ANDROID_BINDER_IPC = n
