1 files changed, 34 insertions, 13 deletions

diff --git a/drivers/char/pty.c b/drivers/char/pty.c
index d83a43130df4..ad46eae1f9bb 100644
--- a/drivers/char/pty.c
+++ b/drivers/char/pty.c
@@ -62,7 +62,9 @@ static void pty_close(struct tty_struct *tty, struct file *filp)
                 if (tty->driver == ptm_driver)
                         devpts_pty_kill(tty->link);
 #endif
+                tty_unlock();
                 tty_vhangup(tty->link);
+                tty_lock();
         }
 }
 
@@ -171,6 +173,23 @@ static int pty_set_lock(struct tty_struct *tty, int __user *arg)
         return 0;
 }
 
+/* Send a signal to the slave */
+static int pty_signal(struct tty_struct *tty, int sig)
+{
+        unsigned long flags;
+        struct pid *pgrp;
+
+        if (tty->link) {
+                spin_lock_irqsave(&tty->link->ctrl_lock, flags);
+                pgrp = get_pid(tty->link->pgrp);
+                spin_unlock_irqrestore(&tty->link->ctrl_lock, flags);
+
+                kill_pgrp(pgrp, sig, 1);
+                put_pid(pgrp);
+        }
+        return 0;
+}
+
 static void pty_flush_buffer(struct tty_struct *tty)
 {
         struct tty_struct *to = tty->link;
@@ -321,6 +340,8 @@ static int pty_bsd_ioctl(struct tty_struct *tty, struct file *file,
         switch (cmd) {
         case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
                 return pty_set_lock(tty, (int __user *) arg);
+        case TIOCSIG:    /* Send signal to other side of pty */
+                return pty_signal(tty, (int) arg);
         }
         return -ENOIOCTLCMD;
 }
@@ -476,6 +497,8 @@ static int pty_unix98_ioctl(struct tty_struct *tty, struct file *file,
                 return pty_set_lock(tty, (int __user *)arg);
         case TIOCGPTN: /* Get PT Number */
                 return put_user(tty->index, (unsigned int __user *)arg);
+        case TIOCSIG:    /* Send signal to other side of pty */
+                return pty_signal(tty, (int) arg);
         }
 
         return -ENOIOCTLCMD;
@@ -626,7 +649,7 @@ static const struct tty_operations pty_unix98_ops = {
  *              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;
@@ -635,11 +658,14 @@ static int __ptmx_open(struct inode *inode, struct file *filp)
         nonseekable_open(inode, filp);
 
         /* find a device that is not in use. */
+        tty_lock();
         index = devpts_new_index(inode);
+        tty_unlock();
         if (index < 0)
                 return index;
 
         mutex_lock(&tty_mutex);
+        tty_lock();
         tty = tty_init_dev(ptm_driver, index, 1);
         mutex_unlock(&tty_mutex);
 
@@ -657,26 +683,21 @@ static int __ptmx_open(struct inode *inode, struct file *filp)
                 goto out1;
 
         retval = ptm_driver->ops->open(tty, filp);
-        if (!retval)
-                return 0;
+        if (retval)
+                goto out2;
 out1:
+        tty_unlock();
+        return retval;
+out2:
+        tty_unlock();
         tty_release(inode, filp);
         return retval;
 out:
         devpts_kill_index(inode, index);
+        tty_unlock();
         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;
-}
-
 static struct file_operations ptmx_fops;
 
 static void __init unix98_pty_init(void)