diff options
| -rw-r--r-- | drivers/tty/tty_io.c | 14 | ||||
| -rw-r--r-- | drivers/tty/tty_ldisc.c | 4 | ||||
| -rw-r--r-- | drivers/tty/vt/selection.c | 2 |
3 files changed, 18 insertions, 2 deletions
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index 71a9409c8d7e..eb26754b2e5d 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -1068,6 +1068,8 @@ static ssize_t tty_read(struct file *file, char __user *buf, size_t count, /* We want to wait for the line discipline to sort out in this situation */ ld = tty_ldisc_ref_wait(tty); + if (!ld) + return hung_up_tty_read(file, buf, count, ppos); if (ld->ops->read) i = ld->ops->read(tty, file, buf, count); else @@ -1242,6 +1244,8 @@ static ssize_t tty_write(struct file *file, const char __user *buf, if (tty->ops->write_room == NULL) tty_err(tty, "missing write_room method\n"); ld = tty_ldisc_ref_wait(tty); + if (!ld) + return hung_up_tty_write(file, buf, count, ppos); if (!ld->ops->write) ret = -EIO; else @@ -2201,6 +2205,8 @@ static unsigned int tty_poll(struct file *filp, poll_table *wait) return 0; ld = tty_ldisc_ref_wait(tty); + if (!ld) + return hung_up_tty_poll(filp, wait); if (ld->ops->poll) ret = ld->ops->poll(tty, filp, wait); tty_ldisc_deref(ld); @@ -2290,6 +2296,8 @@ static int tiocsti(struct tty_struct *tty, char __user *p) return -EFAULT; tty_audit_tiocsti(tty, ch); ld = tty_ldisc_ref_wait(tty); + if (!ld) + return -EIO; ld->ops->receive_buf(tty, &ch, &mbz, 1); tty_ldisc_deref(ld); return 0; @@ -2682,6 +2690,8 @@ static int tiocgetd(struct tty_struct *tty, int __user *p) int ret; ld = tty_ldisc_ref_wait(tty); + if (!ld) + return -EIO; ret = put_user(ld->ops->num, p); tty_ldisc_deref(ld); return ret; @@ -2979,6 +2989,8 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) return retval; } ld = tty_ldisc_ref_wait(tty); + if (!ld) + return hung_up_tty_ioctl(file, cmd, arg); retval = -EINVAL; if (ld->ops->ioctl) { retval = ld->ops->ioctl(tty, file, cmd, arg); @@ -3007,6 +3019,8 @@ static long tty_compat_ioctl(struct file *file, unsigned int cmd, } ld = tty_ldisc_ref_wait(tty); + if (!ld) + return hung_up_tty_compat_ioctl(file, cmd, arg); if (ld->ops->compat_ioctl) retval = ld->ops->compat_ioctl(tty, file, cmd, arg); else diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index 14d2165ba270..d6805e1aee59 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -262,8 +262,8 @@ const struct file_operations tty_ldiscs_proc_fops = { * against a discipline change, such as an existing ldisc reference * (which we check for) * - * Note: only callable from a file_operations routine (which - * guarantees tty->ldisc != NULL when the lock is acquired). + * Note: a file_operations routine (read/poll/write) should use this + * function to wait for any ldisc lifetime events to finish. */ struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *tty) diff --git a/drivers/tty/vt/selection.c b/drivers/tty/vt/selection.c index 381a2b13682c..4dd9dd2270a0 100644 --- a/drivers/tty/vt/selection.c +++ b/drivers/tty/vt/selection.c @@ -347,6 +347,8 @@ int paste_selection(struct tty_struct *tty) console_unlock(); ld = tty_ldisc_ref_wait(tty); + if (!ld) + return -EIO; /* ldisc was hung up */ tty_buffer_lock_exclusive(&vc->port); add_wait_queue(&vc->paste_wait, &wait); |