From: Tao Ning <ningtao@sangfor.com.cn>
Date: Wed, 14 Aug 2019 13:07:46 +0000 (+0800)
Subject: osd/PrimaryLogPG: Avoid accessing destroyed references in finish_degraded_object
X-Git-Tag: v13.2.7~142^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=57f2210dc868f21cddf178c838d8d349c5bf6db1;p=ceph.git

osd/PrimaryLogPG: Avoid accessing destroyed references in finish_degraded_object

As follows:
for (auto i = callbacks_for_degraded_object.begin(); i != callbacks_for_degraded_object.end();) {
    finish_degraded_object((i++)->first);
}

void PrimaryLogPG::finish_degraded_object(const hobject_t oid)
{
  if (callbacks_for_degraded_object.count(oid)) {
    contexts.swap(callbacks_for_degraded_object[oid]);
    callbacks_for_degraded_object.erase(oid);   // Release
  }

  map<hobject_t, snapid_t>::iterator i = objects_blocked_on_degraded_snap.find(
    oid.get_head());  // Access
  ...
}

Fixes: https://tracker.ceph.com/issues/41250
Signed-off-by: Tao Ning <ningtao@sangfor.com.cn>
(cherry picked from commit 86d55c1a0ddb48efc0c1934728d27f22cf49dfa1)

Conflicts: src/osd/PGBackend.h: `PrimaryLogPG` derives from
`PGBackend::Listener` in mimic, and it's `PGBackend::Listener` 's only
derived class. so we need to update `PGBackend::Listener` accordingly.
---

diff --git a/src/osd/PGBackend.h b/src/osd/PGBackend.h
index f8317a9da94a..cb4dcc46471e 100644
--- a/src/osd/PGBackend.h
+++ b/src/osd/PGBackend.h
@@ -106,7 +106,7 @@ typedef ceph::shared_ptr<const OSDMap> OSDMapRef;
        const hobject_t oid) = 0;
 
      virtual void failed_push(const list<pg_shard_t> &from, const hobject_t &soid) = 0;
-     virtual void finish_degraded_object(const hobject_t& oid) = 0;
+     virtual void finish_degraded_object(const hobject_t oid) = 0;
      virtual void primary_failed(const hobject_t &soid) = 0;
      virtual bool primary_error(const hobject_t& soid, eversion_t v) = 0;
      virtual void cancel_pull(const hobject_t &soid) = 0;
diff --git a/src/osd/PrimaryLogPG.cc b/src/osd/PrimaryLogPG.cc
index 0a0c2967fe0b..6c2fe17ff451 100644
--- a/src/osd/PrimaryLogPG.cc
+++ b/src/osd/PrimaryLogPG.cc
@@ -11418,7 +11418,7 @@ void PrimaryLogPG::remove_missing_object(const hobject_t &soid,
   assert(r == 0);
 }
 
-void PrimaryLogPG::finish_degraded_object(const hobject_t& oid)
+void PrimaryLogPG::finish_degraded_object(const hobject_t oid)
 {
   dout(10) << __func__ << " " << oid << dendl;
   if (callbacks_for_degraded_object.count(oid)) {
diff --git a/src/osd/PrimaryLogPG.h b/src/osd/PrimaryLogPG.h
index 24ee09067aca..6c411d407b5e 100644
--- a/src/osd/PrimaryLogPG.h
+++ b/src/osd/PrimaryLogPG.h
@@ -1096,7 +1096,7 @@ protected:
 				  PGBackend::RecoveryHandle *h,
 				  bool *work_started);
 
-  void finish_degraded_object(const hobject_t& oid);
+  void finish_degraded_object(const hobject_t oid);
 
   // Cancels/resets pulls from peer
   void check_recovery_sources(const OSDMapRef& map) override ;