Commit 6509f309 authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Greg Kroah-Hartman
Browse files

tty: hide unused pty_get_peer function 



TIOCGPTPEER is only used for unix98 PTYs, and we get a warning
when those are disabled:

drivers/tty/pty.c:466:12: error: 'pty_get_peer' defined but not used [-Werror=unused-function]

This moves the respective functions inside of the existing #ifdef.

Fixes: 54ebbfb1 ("tty: add TIOCGPTPEER ioctl")
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Acked-by: default avatarAleksa Sarai <asarai@suse.de>
Reviewed-by: default avatarKees Cook <keescook@chromium.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 3ee5447e

drivers/tty/pty.c

+42 −43
Original line number Diff line number Diff line
@@ -448,48 +448,6 @@ err: 
	return retval;

}



/**

 *	pty_open_peer - open the peer of a pty

 *	@tty: the peer of the pty being opened

 *

 *	Open the cached dentry in tty->link, providing a safe way for userspace

 *	to get the slave end of a pty (where they have the master fd and cannot

 *	access or trust the mount namespace /dev/pts was mounted inside).

 */

static struct file *pty_open_peer(struct tty_struct *tty, int flags)

{

	if (tty->driver->subtype != PTY_TYPE_MASTER)

		return ERR_PTR(-EIO);

	return dentry_open(tty->link->driver_data, flags, current_cred());

}



static int pty_get_peer(struct tty_struct *tty, int flags)

{

	int fd = -1;

	struct file *filp = NULL;

	int retval = -EINVAL;



	fd = get_unused_fd_flags(0);

	if (fd < 0) {

		retval = fd;

		goto err;

	}



	filp = pty_open_peer(tty, flags);

	if (IS_ERR(filp)) {

		retval = PTR_ERR(filp);

		goto err_put;

	}



	fd_install(fd, filp);

	return fd;



err_put:

	put_unused_fd(fd);

err:

	return retval;

}



static void pty_cleanup(struct tty_struct *tty)

{

	tty_port_put(tty->port);
@@ -646,9 +604,50 @@ static inline void legacy_pty_init(void) { } 


/* Unix98 devices */

#ifdef CONFIG_UNIX98_PTYS



static struct cdev ptmx_cdev;



/**

 *	pty_open_peer - open the peer of a pty

 *	@tty: the peer of the pty being opened

 *

 *	Open the cached dentry in tty->link, providing a safe way for userspace

 *	to get the slave end of a pty (where they have the master fd and cannot

 *	access or trust the mount namespace /dev/pts was mounted inside).

 */

static struct file *pty_open_peer(struct tty_struct *tty, int flags)

{

	if (tty->driver->subtype != PTY_TYPE_MASTER)

		return ERR_PTR(-EIO);

	return dentry_open(tty->link->driver_data, flags, current_cred());

}



static int pty_get_peer(struct tty_struct *tty, int flags)

{

	int fd = -1;

	struct file *filp = NULL;

	int retval = -EINVAL;



	fd = get_unused_fd_flags(0);

	if (fd < 0) {

		retval = fd;

		goto err;

	}



	filp = pty_open_peer(tty, flags);

	if (IS_ERR(filp)) {

		retval = PTR_ERR(filp);

		goto err_put;

	}



	fd_install(fd, filp);

	return fd;



err_put:

	put_unused_fd(fd);

err:

	return retval;

}



static int pty_unix98_ioctl(struct tty_struct *tty,

			    unsigned int cmd, unsigned long arg)

{

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