Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (58 commits)
  tty: split the lock up a bit further
  tty: Move the leader test in disassociate
  tty: Push the bkl down a bit in the hangup code
  tty: Push the lock down further into the ldisc code
  tty: push the BKL down into the handlers a bit
  tty: moxa: split open lock
  tty: moxa: Kill the use of lock_kernel
  tty: moxa: Fix modem op locking
  tty: moxa: Kill off the throttle method
  tty: moxa: Locking clean up
  tty: moxa: rework the locking a bit
  tty: moxa: Use more tty_port ops
  tty: isicom: fix deadlock on shutdown
  tty: mxser: Use the new locking rules to fix setserial properly
  tty: mxser: use the tty_port_open method
  tty: isicom: sort out the board init logic
  tty: isicom: switch to the new tty_port_open helper
  tty: tty_port: Add a kref object to the tty port
  tty: istallion: tty port open/close methods
  tty: stallion: Convert to the tty_port_open/close methods
  ...

1 files changed, 14 insertions, 2 deletions

diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index d5f8c96964be..8882ecc0f1bf 100644
--- a/fs/devpts/inode.c
+++ b/fs/devpts/inode.c
@@ -517,11 +517,23 @@ int devpts_pty_new(struct inode *ptmx_inode, struct tty_struct *tty)
 
 struct tty_struct *devpts_get_tty(struct inode *pts_inode, int number)
 {
+	struct dentry *dentry;
+	struct tty_struct *tty;
+
 	BUG_ON(pts_inode->i_rdev == MKDEV(TTYAUX_MAJOR, PTMX_MINOR));
 
+	/* Ensure dentry has not been deleted by devpts_pty_kill() */
+	dentry = d_find_alias(pts_inode);
+	if (!dentry)
+		return NULL;
+
+	tty = NULL;
 	if (pts_inode->i_sb->s_magic == DEVPTS_SUPER_MAGIC)
-		return (struct tty_struct *)pts_inode->i_private;
-	return NULL;
+		tty = (struct tty_struct *)pts_inode->i_private;
+
+	dput(dentry);
+
+	return tty;
 }
 
 void devpts_pty_kill(struct tty_struct *tty)