audit: use spin_lock_irqsave/restore in audit tty code

Some of the callers of the audit tty function use spin_lock_irqsave/restore.
We were using the forced always enable version, which seems really bad.
Since I don't know every one of these code paths well enough, it makes
sense to just switch everything to the safe version.  Maybe it's a
little overzealous, but it's a lot better than an unlucky deadlock when
we return to a caller with irq enabled and they expect it to be
disabled.

Signed-off-by: Eric Paris <eparis@redhat.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/kernel/audit.c b/kernel/audit.c
index 44803f25b236..241aa8593fa8 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -804,10 +804,11 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
         case AUDIT_TTY_GET: {
                 struct audit_tty_status s;
                 struct task_struct *tsk = current;
+                unsigned long flags;
 
-                spin_lock_irq(&tsk->sighand->siglock);
+                spin_lock_irqsave(&tsk->sighand->siglock, flags);
                 s.enabled = tsk->signal->audit_tty != 0;
-                spin_unlock_irq(&tsk->sighand->siglock);
+                spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
 
                 audit_send_reply(NETLINK_CB(skb).portid, seq,
                                  AUDIT_TTY_GET, 0, 0, &s, sizeof(s));
@@ -816,6 +817,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
         case AUDIT_TTY_SET: {
                 struct audit_tty_status *s;
                 struct task_struct *tsk = current;
+                unsigned long flags;
 
                 if (nlh->nlmsg_len < sizeof(struct audit_tty_status))
                         return -EINVAL;
@@ -823,9 +825,9 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
                 if (s->enabled != 0 && s->enabled != 1)
                         return -EINVAL;
 
-                spin_lock_irq(&tsk->sighand->siglock);
+                spin_lock_irqsave(&tsk->sighand->siglock, flags);
                 tsk->signal->audit_tty = s->enabled != 0;
-                spin_unlock_irq(&tsk->sighand->siglock);
+                spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
                 break;
         }
         default: