1 files changed, 17 insertions, 0 deletions
diff --git a/kernel/exit.c b/kernel/exit.c
index b194febf5799..676149a4ac5f 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -96,6 +96,14 @@ static void __exit_signal(struct task_struct *tsk)
 		sig->tty = NULL;
 	} else {
 		/*
+		 * This can only happen if the caller is de_thread().
+		 * FIXME: this is the temporary hack, we should teach
+		 * posix-cpu-timers to handle this case correctly.
+		 */
+		if (unlikely(has_group_leader_pid(tsk)))
+			posix_cpu_timers_exit_group(tsk);
+
+		/*
 		 * If there is any task waiting for the group exit
 		 * then notify it:
 		 */
@@ -906,6 +914,15 @@ NORET_TYPE void do_exit(long code)
 	if (unlikely(!tsk->pid))
 		panic("Attempted to kill the idle task!");
 
+	/*
+	 * If do_exit is called because this processes oopsed, it's possible
+	 * that get_fs() was left as KERNEL_DS, so reset it to USER_DS before
+	 * continuing. Amongst other possible reasons, this is to prevent
+	 * mm_release()->clear_child_tid() from writing to a user-controlled
+	 * kernel address.
+	 */
+	set_fs(USER_DS);
+
 	tracehook_report_exit(&code);
 
 	validate_creds_for_do_exit(tsk);