diff options
Diffstat (limited to 'drivers/tty/tty_ldisc.c')
| -rw-r--r-- | drivers/tty/tty_ldisc.c | 23 |
1 files changed, 15 insertions, 8 deletions
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index 629e3c865072..d9e013dc2c08 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -168,12 +168,11 @@ static struct tty_ldisc *tty_ldisc_get(struct tty_struct *tty, int disc) return ERR_CAST(ldops); } - ld = kmalloc(sizeof(struct tty_ldisc), GFP_KERNEL); - if (ld == NULL) { - put_ldops(ldops); - return ERR_PTR(-ENOMEM); - } - + /* + * There is no way to handle allocation failure of only 16 bytes. + * Let's simplify error handling and save more memory. + */ + ld = kmalloc(sizeof(struct tty_ldisc), GFP_KERNEL | __GFP_NOFAIL); ld->ops = ldops; ld->tty = tty; @@ -417,6 +416,10 @@ EXPORT_SYMBOL_GPL(tty_ldisc_flush); * they are not on hot paths so a little discipline won't do * any harm. * + * The line discipline-related tty_struct fields are reset to + * prevent the ldisc driver from re-using stale information for + * the new ldisc instance. + * * Locking: takes termios_rwsem */ @@ -425,6 +428,9 @@ static void tty_set_termios_ldisc(struct tty_struct *tty, int num) down_write(&tty->termios_rwsem); tty->termios.c_line = num; up_write(&tty->termios_rwsem); + + tty->disc_data = NULL; + tty->receive_room = 0; } /** @@ -797,12 +803,13 @@ void tty_ldisc_release(struct tty_struct *tty) * the tty structure is not completely set up when this call is made. */ -void tty_ldisc_init(struct tty_struct *tty) +int tty_ldisc_init(struct tty_struct *tty) { struct tty_ldisc *ld = tty_ldisc_get(tty, N_TTY); if (IS_ERR(ld)) - panic("n_tty: init_tty"); + return PTR_ERR(ld); tty->ldisc = ld; + return 0; } /** |