diff options
Diffstat (limited to 'drivers/char/tty_io.c')
| -rw-r--r-- | drivers/char/tty_io.c | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index abfe24d28c51..95f3596189cf 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -2990,7 +2990,8 @@ static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) { - pid_t pgrp; + struct pid *pgrp; + pid_t pgrp_nr; int retval = tty_check_change(real_tty); if (retval == -EIO) @@ -3001,14 +3002,23 @@ static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t (current->signal->tty != real_tty) || (real_tty->session != process_session(current))) return -ENOTTY; - if (get_user(pgrp, p)) + if (get_user(pgrp_nr, p)) return -EFAULT; - if (pgrp < 0) + if (pgrp_nr < 0) return -EINVAL; - if (session_of_pgrp(pgrp) != process_session(current)) - return -EPERM; - real_tty->pgrp = pgrp; - return 0; + rcu_read_lock(); + pgrp = find_pid(pgrp_nr); + retval = -ESRCH; + if (!pgrp) + goto out_unlock; + retval = -EPERM; + if (session_of_pgrp(pgrp) != task_session(current)) + goto out_unlock; + retval = 0; + real_tty->pgrp = pgrp_nr; +out_unlock: + rcu_read_unlock(); + return retval; } /** |