From 10e603b1e3024c760cd5567dbbc73fbb3c1281f3 Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Wed, 21 Sep 2016 21:57:25 +0800
Subject: [PATCH] client: fix segment fault in
 Client::_invalidate_kernel_dcache().

when umounting, root can be NULL

Fixes: http://tracker.ceph.com/issues/17253
Signed-off-by: Yan, Zheng <zyan@redhat.com>
(cherry picked from commit ddea9a5b78151c0abe834e4a9872f7cf5f918ebc)
---
 src/client/Client.cc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/client/Client.cc b/src/client/Client.cc
index b465cadec55f..189fc265bb0d 100644
--- a/src/client/Client.cc
+++ b/src/client/Client.cc
@@ -3923,6 +3923,8 @@ public:
 
 void Client::_invalidate_kernel_dcache()
 {
+  if (unmounting)
+    return;
   if (can_invalidate_dentries && dentry_invalidate_cb && root->dir) {
     for (ceph::unordered_map<string, Dentry*>::iterator p = root->dir->dentries.begin();
 	 p != root->dir->dentries.end();
-- 
2.47.3