Merge tag 'v5.0-rc6' into devel

Linux 5.0-rc6

1 files changed, 8 insertions, 6 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index a4fdad475594..fed298c0cb39 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -856,10 +856,6 @@ static int tun_attach(struct tun_struct *tun, struct file *file,
 		err = 0;
 	}
 
-	rcu_assign_pointer(tfile->tun, tun);
-	rcu_assign_pointer(tun->tfiles[tun->numqueues], tfile);
-	tun->numqueues++;
-
 	if (tfile->detached) {
 		tun_enable_queue(tfile);
 	} else {
@@ -870,12 +866,18 @@ static int tun_attach(struct tun_struct *tun, struct file *file,
 	if (rtnl_dereference(tun->xdp_prog))
 		sock_set_flag(&tfile->sk, SOCK_XDP);
 
-	tun_set_real_num_queues(tun);
-
 	/* device is allowed to go away first, so no need to hold extra
 	 * refcnt.
 	 */
 
+	/* Publish tfile->tun and tun->tfiles only after we've fully
+	 * initialized tfile; otherwise we risk using half-initialized
+	 * object.
+	 */
+	rcu_assign_pointer(tfile->tun, tun);
+	rcu_assign_pointer(tun->tfiles[tun->numqueues], tfile);
+	tun->numqueues++;
+	tun_set_real_num_queues(tun);
 out:
 	return err;
 }