From cbbb456d6f40eb025e2458463228236bdd9fe0a5 Mon Sep 17 00:00:00 2001
Message-Id: <cbbb456d6f40eb025e2458463228236bdd9fe0a5.1386348947.git.jdenemar@redhat.com>
From: Michal Privoznik <mprivozn@redhat.com>
Date: Tue, 3 Dec 2013 15:31:39 +0100
Subject: [PATCH] daemon: Run virStateCleanup conditionally
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https://bugzilla.redhat.com/show_bug.cgi?id=1033061

Currently, initialization of drivers is done in a separate thread. This
is done for several reasons: a driver that is initialized may require
running event loop, it may take ages to initialize driver (e.g. due to
autostarting domains). While the thread is spawn and run, the main()
continues its execution. However, if something goes bad, or the event
loop is just exited (e.g. due to a --timeout or SIGINT) we try to
cleanup all the drivers. So we have two threads running Initialize() and
Cleanup() concurrently. This may result in accessing stale pointers -
e.g. netcf driver will free() itself in stateCleanup callback, while the
init thread may come, open a dummy connection in order to autostart some
domains and voilà: do_open() iterates over interface drivers and
accesses stale netcf driver.

The fix consists in not running stateCleanup if the init thread is still
running.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
(cherry picked from commit a602e90bc1e0743d7e801b730e303674d24fa89f)
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
---
 daemon/libvirtd.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/daemon/libvirtd.c b/daemon/libvirtd.c
index 808bd4b..8576bfe 100644
--- a/daemon/libvirtd.c
+++ b/daemon/libvirtd.c
@@ -108,6 +108,8 @@ virNetServerProgramPtr remoteProgram = NULL;
 virNetServerProgramPtr qemuProgram = NULL;
 virNetServerProgramPtr lxcProgram = NULL;
 
+volatile bool driversInitialized = false;
+
 enum {
     VIR_DAEMON_ERR_NONE = 0,
     VIR_DAEMON_ERR_PIDFILE,
@@ -912,6 +914,8 @@ static void daemonRunStateInit(void *opaque)
         goto cleanup;
     }
 
+    driversInitialized = true;
+
 #ifdef HAVE_DBUS
     /* Tie the non-priviledged libvirtd to the session/shutdown lifecycle */
     if (!virNetServerIsPrivileged(srv)) {
@@ -1546,7 +1550,8 @@ cleanup:
 
     daemonConfigFree(config);
 
-    virStateCleanup();
+    if (driversInitialized)
+        virStateCleanup();
 
     return ret;
 }
-- 
1.8.4.5