2 files changed, 15 insertions, 2 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index a2c6caaaae93..62b2b3005019 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -432,6 +432,7 @@ static void tun_setup(struct net_device *dev)
         init_waitqueue_head(&tun->read_wait);
 
         tun->owner = -1;
+        tun->group = -1;
 
         SET_MODULE_OWNER(dev);
         dev->open = tun_net_open;
@@ -467,8 +468,11 @@ static int tun_set_iff(struct file *file, struct ifreq *ifr)
                         return -EBUSY;
 
                 /* Check permissions */
-                if (tun->owner != -1 &&
-                    current->euid != tun->owner && !capable(CAP_NET_ADMIN))
+                if (((tun->owner != -1 &&
+                      current->euid != tun->owner) ||
+                     (tun->group != -1 &&
+                      current->egid != tun->group)) &&
+                     !capable(CAP_NET_ADMIN))
                         return -EPERM;
         }
         else if (__dev_get_by_name(ifr->ifr_name))
@@ -610,6 +614,13 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file,
                 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
                 break;
 
+        case TUNSETGROUP:
+                /* Set group of the device */
+                tun->group= (gid_t) arg;
+
+                DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
+                break;
+
         case TUNSETLINK:
                 /* Only allow setting the type when the interface is down */
                 if (tun->dev->flags & IFF_UP) {
diff --git a/include/linux/if_tun.h b/include/linux/if_tun.h
index 88aef7b86ef4..42eb6945b93e 100644
--- a/include/linux/if_tun.h
+++ b/include/linux/if_tun.h
@@ -36,6 +36,7 @@ struct tun_struct {
         unsigned long           flags;
         int                     attached;
         uid_t                   owner;
+        gid_t                   group;
 
         wait_queue_head_t       read_wait;
         struct sk_buff_head     readq;
@@ -78,6 +79,7 @@ struct tun_struct {
 #define TUNSETPERSIST _IOW('T', 203, int) 
 #define TUNSETOWNER   _IOW('T', 204, int)
 #define TUNSETLINK    _IOW('T', 205, int)
+#define TUNSETGROUP   _IOW('T', 206, int)
 
 /* TUNSETIFF ifr flags */
 #define IFF_TUN         0x0001