From: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> commit 17749851eb9ca2298e7c3b81aae4228961b36f28 upstream. In commit "tty: implement write_iter", I left the write_iter conversion of the hung up tty case alone, because I incorrectly thought it didn't matter. Jiri showed me the errors of my ways, and pointed out the problems with that incomplete conversion. Fix it all up. Reported-by: Jiri Slaby <jirislaby@xxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Reviewed-by: Jiri Slaby <jirislaby@xxxxxxxxxx> Link: https://lore.kernel.org/r/CAHk-=wh+-rGsa=xruEWdg_fJViFG8rN9bpLrfLz=_yBYh2tBhA@xxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/tty/tty_io.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -437,8 +437,7 @@ static ssize_t hung_up_tty_read(struct f return 0; } -static ssize_t hung_up_tty_write(struct file *file, const char __user *buf, - size_t count, loff_t *ppos) +static ssize_t hung_up_tty_write(struct kiocb *iocb, struct iov_iter *from) { return -EIO; } @@ -504,7 +503,7 @@ static const struct file_operations cons static const struct file_operations hung_up_tty_fops = { .llseek = no_llseek, .read = hung_up_tty_read, - .write = hung_up_tty_write, + .write_iter = hung_up_tty_write, .poll = hung_up_tty_poll, .unlocked_ioctl = hung_up_tty_ioctl, .compat_ioctl = hung_up_tty_compat_ioctl, @@ -1045,7 +1044,9 @@ static ssize_t tty_write(struct kiocb *i if (tty->ops->write_room == NULL) tty_err(tty, "missing write_room method\n"); ld = tty_ldisc_ref_wait(tty); - if (!ld || !ld->ops->write) + if (!ld) + return hung_up_tty_write(iocb, from); + if (!ld->ops->write) ret = -EIO; else ret = do_tty_write(ld->ops->write, tty, file, from);
