tty: Make get_current_tty use a kref
We now return a kref covered tty reference. That ensures the tty structure
doesn't go away when you have a return from get_current_tty. This is not
enough to protect you from most of the resources being freed behind your
back - yet.
[Updated to include fixes for SELinux problems found by Andrew Morton and
an s390 leak found while debugging the former]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/dquot.c b/fs/dquot.c
index 8ec4d6c..7417a6c 100644
--- a/fs/dquot.c
+++ b/fs/dquot.c
@@ -897,8 +897,9 @@
mutex_lock(&tty_mutex);
tty = get_current_tty();
+ mutex_unlock(&tty_mutex);
if (!tty)
- goto out_lock;
+ return;
tty_write_message(tty, dquot->dq_sb->s_id);
if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN)
tty_write_message(tty, ": warning, ");
@@ -926,8 +927,7 @@
break;
}
tty_write_message(tty, msg);
-out_lock:
- mutex_unlock(&tty_mutex);
+ tty_kref_put(tty);
}
#endif