Unverified Commit 3fd5edfe authored by Christian Brauner's avatar Christian Brauner
Browse files

tty: convert ptm_open_peer() to FD_ADD() 

Christian Brauner <brauner@kernel.org> says:

The fix sent in [1] was squashed into this commit.

Fixes: https://lore.kernel.org/37ac7af5-584f-4768-a462-4d1071c43eaf@sirena.org.uk [1]
Reported-by: Mark Brown <broonie@kernel.org> [1]
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> [1]
Link: https://patch.msgid.link/20251123-work-fd-prepare-v4-42-b6efa1706cfd@kernel.org


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent af66279a

drivers/tty/pty.c

+18 −33
Original line number Diff line number Diff line
@@ -589,6 +589,23 @@ static inline void legacy_pty_init(void) { } 
#ifdef CONFIG_UNIX98_PTYS

static struct cdev ptmx_cdev;



static struct file *ptm_open_peer_file(struct file *master,

				       struct tty_struct *tty, int flags)

{

	struct path path;

	struct file *file;



	/* Compute the slave's path */

	path.mnt = devpts_mntget(master, tty->driver_data);

	if (IS_ERR(path.mnt))

		return ERR_CAST(path.mnt);

	path.dentry = tty->link->driver_data;



	file = dentry_open(&path, flags, current_cred());

	mntput(path.mnt);

	return file;

}



/**

 *	ptm_open_peer - open the peer of a pty

 *	@master: the open struct file of the ptmx device node
@@ -601,42 +618,10 @@ static struct cdev ptmx_cdev; 
 */

int ptm_open_peer(struct file *master, struct tty_struct *tty, int flags)

{

	int fd;

	struct file *filp;

	int retval = -EINVAL;

	struct path path;



	if (tty->driver != ptm_driver)

		return -EIO;



	fd = get_unused_fd_flags(flags);

	if (fd < 0) {

		retval = fd;

		goto err;

	}



	/* Compute the slave's path */

	path.mnt = devpts_mntget(master, tty->driver_data);

	if (IS_ERR(path.mnt)) {

		retval = PTR_ERR(path.mnt);

		goto err_put;

	}

	path.dentry = tty->link->driver_data;



	filp = dentry_open(&path, flags, current_cred());

	mntput(path.mnt);

	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;

	return FD_ADD(flags, ptm_open_peer_file(master, tty, flags));

}



static int pty_unix98_ioctl(struct tty_struct *tty,