From: Daniel Hokka Zakrisson <dhokka@cs.princeton.edu>
Date: Mon, 7 Jul 2008 16:02:42 +0000 (+0000)
Subject: chrooting is not thread-safe. Install the initscript before calling VServer.start... 
X-Git-Tag: NodeManager-1.8-0~28
X-Git-Url: http://git.onelab.eu/?p=nodemanager.git;a=commitdiff_plain;h=fb5967c9d175cf3bfb8e41b805fe60aec20831a8

chrooting is not thread-safe. Install the initscript before calling VServer.start instead, where we know we're the only thread running.
---

diff --git a/sliver_vs.py b/sliver_vs.py
index b889e32..90b2ca7 100644
--- a/sliver_vs.py
+++ b/sliver_vs.py
@@ -166,16 +166,7 @@ class Sliver_VS(accounts.Account, vserver.VServer):
         new_initscript = rec['initscript']
         if new_initscript != self.initscript:
             self.initscript = new_initscript
-            logger.log('%s: installing initscript' % self.name)
-            def install_initscript():
-                flags = os.O_WRONLY | os.O_CREAT | os.O_TRUNC
-                fd = os.open('/etc/rc.vinit', flags, 0755)
-                os.write(fd, new_initscript)
-                os.close(fd)
-            try:
-                self.chroot_call(install_initscript)
-                self.initscriptchanged = True
-            except: logger.log_exc(self.name)
+            self.initscriptchanged = True
 
         accounts.Account.configure(self, rec)  # install ssh keys
 
@@ -185,6 +176,17 @@ class Sliver_VS(accounts.Account, vserver.VServer):
             time.sleep(delay)
             child_pid = os.fork()
             if child_pid == 0:
+                if self.initscriptchanged:
+                    logger.log('%s: installing initscript' % self.name)
+                    def install_initscript():
+                        flags = os.O_WRONLY | os.O_CREAT | os.O_TRUNC
+                        fd = os.open('/etc/rc.vinit', flags, 0755)
+                        os.write(fd, new_initscript)
+                        os.close(fd)
+                    try:
+                        self.chroot_call(install_initscript)
+                        self.initscriptchanged = False
+                    except: logger.log_exc(self.name)
                 # VServer.start calls fork() internally, 
                 # so just close the nonstandard fds and fork once to avoid creating zombies
                 tools.close_nonstandard_fds()
@@ -192,7 +194,6 @@ class Sliver_VS(accounts.Account, vserver.VServer):
                 os._exit(0)
             else: os.waitpid(child_pid, 0)
         else: logger.log('%s: not starting, is not enabled' % self.name)
-        self.initscriptchanged = False
 
     def stop(self):
         logger.log('%s: stopping' % self.name)