diff --git a/kernel/fork.c b/kernel/fork.c
index dfeadf4..b258020 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1116,6 +1116,9 @@
 			__get_cpu_var(process_counts)++;
 	}
 
+	if (!current->signal->tty && p->signal->tty)
+		p->signal->tty = NULL;
+
 	nr_threads++;
 	total_forks++;
 	write_unlock_irq(&tasklist_lock);