From 3017b78225e4e0f74f81218107ed2770ab203fff Mon Sep 17 00:00:00 2001
From: Yanhu Cao <gmayyyha@gmail.com>
Date: Wed, 7 Apr 2021 10:13:07 +0800
Subject: [PATCH] mds: ensure export_pin rank < max_mds

Signed-off-by: Yanhu Cao <gmayyyha@gmail.com>
---
 src/mds/Server.cc | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/mds/Server.cc b/src/mds/Server.cc
index 4869ff2472c..67b5c0db934 100644
--- a/src/mds/Server.cc
+++ b/src/mds/Server.cc
@@ -5704,6 +5704,10 @@ void Server::handle_set_vxattr(MDRequestRef& mdr, CInode *cur)
     try {
       rank = boost::lexical_cast<mds_rank_t>(value);
       if (rank < 0) rank = MDS_RANK_NONE;
+      else if (rank >= MAX_MDS) {
+        respond_to_request(mdr, -CEPHFS_EDOM);
+        return;
+      }
     } catch (boost::bad_lexical_cast const&) {
       dout(10) << "bad vxattr value, unable to parse int for " << name << dendl;
       respond_to_request(mdr, -CEPHFS_EINVAL);
-- 
2.39.5