1 files changed, 34 insertions, 7 deletions

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 750131010af0..047a17339f83 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -2665,7 +2665,7 @@ static void release_dev(struct file *filp)
  *               ->siglock protects ->signal/->sighand
  */
 
-static int tty_open(struct inode *inode, struct file *filp)
+static int __tty_open(struct inode *inode, struct file *filp)
 {
         struct tty_struct *tty;
         int noctty, retval;
@@ -2779,6 +2779,19 @@ got_driver:
         return 0;
 }
 
+/* BKL pushdown: scary code avoidance wrapper */
+static int tty_open(struct inode *inode, struct file *filp)
+{
+        int ret;
+
+        lock_kernel();
+        ret = __tty_open(inode, filp);
+        unlock_kernel();
+        return ret;
+}
+
+
+
 #ifdef CONFIG_UNIX98_PTYS
 /**
  *      ptmx_open               -       open a unix 98 pty master
@@ -2792,7 +2805,7 @@ got_driver:
  *              allocated_ptys_lock handles the list of free pty numbers
  */
 
-static int ptmx_open(struct inode *inode, struct file *filp)
+static int __ptmx_open(struct inode *inode, struct file *filp)
 {
         struct tty_struct *tty;
         int retval;
@@ -2831,6 +2844,16 @@ out:
         devpts_kill_index(index);
         return retval;
 }
+
+static int ptmx_open(struct inode *inode, struct file *filp)
+{
+        int ret;
+
+        lock_kernel();
+        ret = __ptmx_open(inode, filp);
+        unlock_kernel();
+        return ret;
+}
 #endif
 
 /**
@@ -2886,15 +2909,16 @@ static int tty_fasync(int fd, struct file *filp, int on)
 {
         struct tty_struct *tty;
         unsigned long flags;
-        int retval;
+        int retval = 0;
 
+        lock_kernel();
         tty = (struct tty_struct *)filp->private_data;
         if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "tty_fasync"))
-                return 0;
+                goto out;
 
         retval = fasync_helper(fd, filp, on, &tty->fasync);
         if (retval <= 0)
-                return retval;
+                goto out;
 
         if (on) {
                 enum pid_type type;
@@ -2912,12 +2936,15 @@ static int tty_fasync(int fd, struct file *filp, int on)
                 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
                 retval = __f_setown(filp, pid, type, 0);
                 if (retval)
-                        return retval;
+                        goto out;
         } else {
                 if (!tty->fasync && !waitqueue_active(&tty->read_wait))
                         tty->minimum_to_wake = N_TTY_BUF_SIZE;
         }
-        return 0;
+        retval = 0;
+out:
+        unlock_kernel();
+        return retval;
 }
 
 /**