1 files changed, 5 insertions, 63 deletions

diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index d8653ab6f498..39afd045f8ef 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -21,7 +21,6 @@
 #include <linux/major.h>
 #include <linux/mm.h>
 #include <linux/init.h>
-#include <linux/sysctl.h>
 #include <linux/device.h>
 #include <linux/uaccess.h>
 #include <linux/bitops.h>
@@ -55,11 +54,8 @@ static void pty_close(struct tty_struct *tty, struct file *filp)
         wake_up_interruptible(&tty->link->write_wait);
         if (tty->driver->subtype == PTY_TYPE_MASTER) {
                 set_bit(TTY_OTHER_CLOSED, &tty->flags);
-#ifdef CONFIG_UNIX98_PTYS
-                if (tty->driver == ptm_driver)
-                        devpts_pty_kill(tty->link);
-#endif
                 tty_unlock();
+                devpts_pty_kill(tty->link);
                 tty_vhangup(tty->link);
                 tty_lock();
         }
@@ -439,55 +435,9 @@ static inline void legacy_pty_init(void) { }
 
 /* Unix98 devices */
 #ifdef CONFIG_UNIX98_PTYS
-/*
- * sysctl support for setting limits on the number of Unix98 ptys allocated.
- * Otherwise one can eat up all kernel memory by opening /dev/ptmx repeatedly.
- */
-int pty_limit = NR_UNIX98_PTY_DEFAULT;
-static int pty_limit_min;
-static int pty_limit_max = NR_UNIX98_PTY_MAX;
-static int pty_count;
 
 static struct cdev ptmx_cdev;
 
-static struct ctl_table pty_table[] = {
-        {
-                .procname       = "max",
-                .maxlen         = sizeof(int),
-                .mode           = 0644,
-                .data           = &pty_limit,
-                .proc_handler   = proc_dointvec_minmax,
-                .extra1         = &pty_limit_min,
-                .extra2         = &pty_limit_max,
-        }, {
-                .procname       = "nr",
-                .maxlen         = sizeof(int),
-                .mode           = 0444,
-                .data           = &pty_count,
-                .proc_handler   = proc_dointvec,
-        }, 
-        {}
-};
-
-static struct ctl_table pty_kern_table[] = {
-        {
-                .procname       = "pty",
-                .mode           = 0555,
-                .child          = pty_table,
-        },
-        {}
-};
-
-static struct ctl_table pty_root_table[] = {
-        {
-                .procname       = "kernel",
-                .mode           = 0555,
-                .child          = pty_kern_table,
-        },
-        {}
-};
-
-
 static int pty_unix98_ioctl(struct tty_struct *tty,
                             unsigned int cmd, unsigned long arg)
 {
@@ -515,10 +465,8 @@ static int pty_unix98_ioctl(struct tty_struct *tty,
 static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver,
                 struct inode *ptm_inode, int idx)
 {
-        struct tty_struct *tty = devpts_get_tty(ptm_inode, idx);
-        if (tty)
-                tty = tty->link;
-        return tty;
+        /* Master must be open via /dev/ptmx */
+        return ERR_PTR(-EIO);
 }
 
 /**
@@ -589,7 +537,6 @@ static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
          */
         tty_driver_kref_get(driver);
         tty->count++;
-        pty_count++;
         return 0;
 err_free_mem:
         deinitialize_tty_struct(o_tty);
@@ -603,7 +550,6 @@ err_free_tty:
 
 static void ptm_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
 {
-        pty_count--;
 }
 
 static void pts_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
@@ -667,9 +613,7 @@ static int ptmx_open(struct inode *inode, struct file *filp)
                 return retval;
 
         /* find a device that is not in use. */
-        tty_lock();
         index = devpts_new_index(inode);
-        tty_unlock();
         if (index < 0) {
                 retval = index;
                 goto err_file;
@@ -677,7 +621,7 @@ static int ptmx_open(struct inode *inode, struct file *filp)
 
         mutex_lock(&tty_mutex);
         tty_lock();
-        tty = tty_init_dev(ptm_driver, index, 1);
+        tty = tty_init_dev(ptm_driver, index);
         mutex_unlock(&tty_mutex);
 
         if (IS_ERR(tty)) {
@@ -704,8 +648,8 @@ err_release:
         tty_release(inode, filp);
         return retval;
 out:
-        devpts_kill_index(inode, index);
         tty_unlock();
+        devpts_kill_index(inode, index);
 err_file:
         tty_free_file(filp);
         return retval;
@@ -762,8 +706,6 @@ static void __init unix98_pty_init(void)
         if (tty_register_driver(pts_driver))
                 panic("Couldn't register Unix98 pts driver");
 
-        register_sysctl_table(pty_root_table);
-
         /* Now create the /dev/ptmx special device */
         tty_default_fops(&ptmx_fops);
         ptmx_fops.open = ptmx_open;