diff options
| author | Eric W. Biederman <ebiederm@xmission.com> | 2007-02-12 00:52:52 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-02-12 09:48:31 -0800 |
| commit | 680a96710041c3c25464b5e093b80ca43cb94f52 (patch) | |
| tree | b68c26beba44e1e138da1b621b1d48ab153f9199 /drivers | |
| parent | cdc623300841bc8f1625c320d5a6cbc52c43c60d (diff) | |
| download | linux-680a96710041c3c25464b5e093b80ca43cb94f52.tar.bz2 | |
[PATCH] tty: clarify disassociate_ctty
The code to look at tty_old_pgrp and send SIGHUP and SIGCONT when it is
present only executes when disassociate_ctty is called from do_exit. Make
this clear by adding an explict on_exit check, and explicitly setting
tty_old_pgrp to 0.
In addition fix the locking by reading tty_old_pgrp under the siglock.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/char/tty_io.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index b9fce77c8f03..ac937f767f23 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -1508,8 +1508,12 @@ void disassociate_ctty(int on_exit) /* XXX: here we race, there is nothing protecting tty */ if (on_exit && tty->driver->type != TTY_DRIVER_TYPE_PTY) tty_vhangup(tty); - } else { - pid_t old_pgrp = current->signal->tty_old_pgrp; + } else if (on_exit) { + pid_t old_pgrp; + spin_lock_irq(¤t->sighand->siglock); + old_pgrp = current->signal->tty_old_pgrp; + current->signal->tty_old_pgrp = 0; + spin_unlock_irq(¤t->sighand->siglock); if (old_pgrp) { kill_pg(old_pgrp, SIGHUP, on_exit); kill_pg(old_pgrp, SIGCONT, on_exit); |