n_tty: Fix EOF push index when termios changes

Commit 40d5e0905a03601d40cd4e46b8690093c2355d03,
'n_tty: Fix EOF push handling' introduced a subtle state
change error wrt EOF push handling when the termios is
changed from non-canonical to canonical mode.

Reset line_start to the current read_tail index, not 0.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index c9a9ddd1d0bc2aa5091d7e1678920df2d9292429..01bf5eb4f2384a66999157ddd855162c8e966f7a 100644 (file)
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -1758,8 +1758,7 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
                canon_change = (old->c_lflag ^ tty->termios.c_lflag) & ICANON;
        if (canon_change) {
                bitmap_zero(ldata->read_flags, N_TTY_BUF_SIZE);
-               ldata->line_start = 0;
-               ldata->canon_head = ldata->read_tail;
+               ldata->line_start = ldata->canon_head = ldata->read_tail;
                ldata->erasing = 0;
                ldata->lnext = 0;
        }