diff options
| author | Peter Hurley <peter@hurleysoftware.com> | 2015-10-11 02:28:44 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-10-18 06:30:49 +0200 |
| commit | 4b41b9539a1e9531f942ededfcdcff372317d2e7 (patch) | |
| tree | c32d3b6fd91a8a8af7d498400c6ef3fcd73c7496 /drivers/tty | |
| parent | tty: core: Use correct spinlock flavor in tiocspgrp() (diff) | |
| download | linux-4b41b9539a1e9531f942ededfcdcff372317d2e7.tar.xz linux-4b41b9539a1e9531f942ededfcdcff372317d2e7.zip | |
tty: Prevent tty teardown during tty_write_message()
tty_write_message() allows the caller to directly write to a specific
tty. Since the line discipline is bypassed for the direct write,
nothing prevents the tty from being torn down after the tty count is
checked.
Hold the tty lock for the duration of the direct write.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/tty_io.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index 071671a8674f..173fdeba0987 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -1200,11 +1200,9 @@ void tty_write_message(struct tty_struct *tty, char *msg) if (tty) { mutex_lock(&tty->atomic_write_lock); tty_lock(tty); - if (tty->ops->write && tty->count > 0) { - tty_unlock(tty); + if (tty->ops->write && tty->count > 0) tty->ops->write(tty, msg, strlen(msg)); - } else - tty_unlock(tty); + tty_unlock(tty); tty_write_unlock(tty); } return; |