1 files changed, 17 insertions, 0 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index b9d3bc6c21ec..ad7e51488291 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -97,6 +97,14 @@ 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:
                  */
@@ -905,6 +913,15 @@ 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);