From: Jason Dillaman <dillaman@redhat.com>
Date: Tue, 25 Sep 2018 18:18:00 +0000 (-0400)
Subject: osdc/Objecter: possible race condition with connection reset
X-Git-Tag: v13.2.3~101^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=refs%2Fpull%2F24600%2Fhead;p=ceph.git

osdc/Objecter: possible race condition with connection reset

If the connection quickly fails before the private session reference
can be associated with the connection, the connection will remain
closed and any OSD ops against the session will remain stuck.

Fixes: http://tracker.ceph.com/issues/36183
Signed-off-by: Jason Dillaman <dillaman@redhat.com>
(cherry picked from commit 74ca33cb49d2c258324447b1ca366ed4e604202a)
---

diff --git a/src/osdc/Objecter.cc b/src/osdc/Objecter.cc
index 98bd84eb6cf6..3ad0bc516e9f 100644
--- a/src/osdc/Objecter.cc
+++ b/src/osdc/Objecter.cc
@@ -1834,6 +1834,7 @@ void Objecter::get_session(Objecter::OSDSession *s)
 
 void Objecter::_reopen_session(OSDSession *s)
 {
+  // rwlock is locked unique
   // s->lock is locked
 
   entity_inst_t inst = osdmap->get_inst(s->osd);
@@ -4417,12 +4418,13 @@ bool Objecter::ms_handle_reset(Connection *con)
   if (!initialized)
     return false;
   if (con->get_peer_type() == CEPH_ENTITY_TYPE_OSD) {
+    unique_lock wl(rwlock);
+
     auto priv = con->get_priv();
     auto session = static_cast<OSDSession*>(priv.get());
     if (session) {
       ldout(cct, 1) << "ms_handle_reset " << con << " session " << session
 		    << " osd." << session->osd << dendl;
-      unique_lock wl(rwlock);
       if (!initialized) {
 	wl.unlock();
 	return false;