diff options
Diffstat (limited to 'drivers/tty/pty.c')
-rw-r--r-- | drivers/tty/pty.c | 49 |
1 files changed, 24 insertions, 25 deletions
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c index b3110040164a..e16a49b507ef 100644 --- a/drivers/tty/pty.c +++ b/drivers/tty/pty.c @@ -263,8 +263,7 @@ static void pty_set_termios(struct tty_struct *tty, { /* See if packet mode change of state. */ if (tty->link && tty->link->packet) { - int extproc = (old_termios->c_lflag & EXTPROC) | - (tty->termios.c_lflag & EXTPROC); + int extproc = (old_termios->c_lflag & EXTPROC) | L_EXTPROC(tty); int old_flow = ((old_termios->c_iflag & IXON) && (old_termios->c_cc[VSTOP] == '\023') && (old_termios->c_cc[VSTART] == '\021')); @@ -406,13 +405,8 @@ static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty, if (legacy) { /* We always use new tty termios data so we can do this the easy way .. */ - retval = tty_init_termios(tty); - if (retval) - goto err_deinit_tty; - - retval = tty_init_termios(o_tty); - if (retval) - goto err_free_termios; + tty_init_termios(tty); + tty_init_termios(o_tty); driver->other->ttys[idx] = o_tty; driver->ttys[idx] = tty; @@ -444,12 +438,7 @@ static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty, tty->count++; o_tty->count++; return 0; -err_free_termios: - if (legacy) - tty_free_termios(tty); -err_deinit_tty: - deinitialize_tty_struct(o_tty); - free_tty_struct(o_tty); + err_put_module: module_put(driver->other->owner); err: @@ -666,22 +655,22 @@ static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver, return tty; } -/* We have no need to install and remove our tty objects as devpts does all - the work for us */ - static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty) { return pty_common_install(driver, tty, false); } +/* this is called once with whichever end is closed last */ static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty) { -} + struct inode *ptmx_inode; -/* this is called once with whichever end is closed last */ -static void pty_unix98_shutdown(struct tty_struct *tty) -{ - devpts_kill_index(tty->driver_data, tty->index); + if (tty->driver->subtype == PTY_TYPE_MASTER) + ptmx_inode = tty->driver_data; + else + ptmx_inode = tty->link->driver_data; + devpts_kill_index(ptmx_inode, tty->index); + devpts_del_ref(ptmx_inode); } static const struct tty_operations ptm_unix98_ops = { @@ -697,7 +686,6 @@ static const struct tty_operations ptm_unix98_ops = { .unthrottle = pty_unthrottle, .ioctl = pty_unix98_ioctl, .resize = pty_resize, - .shutdown = pty_unix98_shutdown, .cleanup = pty_cleanup }; @@ -715,7 +703,6 @@ static const struct tty_operations pty_unix98_ops = { .set_termios = pty_set_termios, .start = pty_start, .stop = pty_stop, - .shutdown = pty_unix98_shutdown, .cleanup = pty_cleanup, }; @@ -773,6 +760,18 @@ static int ptmx_open(struct inode *inode, struct file *filp) set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */ tty->driver_data = inode; + /* + * In the case where all references to ptmx inode are dropped and we + * still have /dev/tty opened pointing to the master/slave pair (ptmx + * is closed/released before /dev/tty), we must make sure that the inode + * is still valid when we call the final pty_unix98_shutdown, thus we + * hold an additional reference to the ptmx inode. For the same /dev/tty + * last close case, we also need to make sure the super_block isn't + * destroyed (devpts instance unmounted), before /dev/tty is closed and + * on its release devpts_kill_index is called. + */ + devpts_add_ref(inode); + tty_add_file(tty, filp); slave_inode = devpts_pty_new(inode, |