From: Sage Weil <sage@newdream.net>
Date: Wed, 24 Nov 2021 18:22:26 +0000 (-0500)
Subject: mgr: fix locking for MetadataUpdate::finish
X-Git-Tag: v15.2.16~12^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=92a74300fecdd6c99b4ff6ba929477d2e324fd1a;p=ceph.git

mgr: fix locking for MetadataUpdate::finish

We need to hold the DaemonState lock here since we are both reading and
writing its content.

Fixes: https://tracker.ceph.com/issues/53393
Signed-off-by: Sage Weil <sage@newdream.net>
(cherry picked from commit 5096685cd623de71a7c45a667e1dd776357fd997)

Conflicts:
	src/mgr/Mgr.cc

Cherry-pick notes:
- state variable was declared outside of if condition in Octopus
---

diff --git a/src/mgr/Mgr.cc b/src/mgr/Mgr.cc
index 18ea0e98132f5..89afc807dbe7d 100644
--- a/src/mgr/Mgr.cc
+++ b/src/mgr/Mgr.cc
@@ -103,19 +103,21 @@ void MetadataUpdate::finish(int r)
       DaemonStatePtr state;
       if (daemon_state.exists(key)) {
         state = daemon_state.get(key);
-        state->hostname = daemon_meta.at("hostname").get_str();
-
-        if (key.type == "mds" || key.type == "mgr" || key.type == "mon") {
-          daemon_meta.erase("name");
-        } else if (key.type == "osd") {
-          daemon_meta.erase("id");
-        }
-        daemon_meta.erase("hostname");
 	map<string,string> m;
-        for (const auto &i : daemon_meta) {
-          m[i.first] = i.second.get_str();
+	{
+	  std::lock_guard l(state->lock);
+	  state->hostname = daemon_meta.at("hostname").get_str();
+
+	  if (key.type == "mds" || key.type == "mgr" || key.type == "mon") {
+	    daemon_meta.erase("name");
+	  } else if (key.type == "osd") {
+	    daemon_meta.erase("id");
+	  }
+	  daemon_meta.erase("hostname");
+	  for (const auto &[key, val] : daemon_meta) {
+	    m.emplace(key, val.get_str());
+	  }
 	}
-
 	daemon_state.update_metadata(state, m);
       } else {
         state = std::make_shared<DaemonState>(daemon_state.types);