Qubes/core-admin
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

qmemman: make memory request handling more defensive

Browse Source 
If getting memory for new VM fails for any reason, make sure that global
lock will be released. Otherwise qmemman will stop functioning at all.

QubesOS/qubes-issues#1636
This commit is contained in:
Marek Marczykowski-Górecki 2016-02-22 17:56:43 +01:00
parent 5546d679c0
commit 0121cb2fd4
No known key found for this signature in database
GPG Key ID: 063938BA42CFA724
1 changed files with 32 additions and 28 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

60
qmemman/qmemman_server.py
View File

@ -175,37 +175,41 @@ class QMemmanReqHandler(SocketServer.BaseRequestHandler):
self.log = logging.getLogger('qmemman.daemon.reqhandler')
got_lock = False
# self.request is the TCP socket connected to the client
while True:
self.data = self.request.recv(1024).strip()
self.log.debug('data={!r}'.format(self.data))
if len(self.data) == 0:
self.log.info('EOF')
try:
# self.request is the TCP socket connected to the client
while True:
self.data = self.request.recv(1024).strip()
self.log.debug('data={!r}'.format(self.data))
if len(self.data) == 0:
self.log.info('EOF')
if got_lock:
global force_refresh_domain_list
force_refresh_domain_list = True
return
# XXX something is wrong here: return without release?
if got_lock:
global force_refresh_domain_list
force_refresh_domain_list = True
global_lock.release()
self.log.debug('global_lock released')
return
self.log.warning('Second request over qmemman.sock?')
return
# XXX something is wrong here: return without release?
self.log.debug('acquiring global_lock')
global_lock.acquire()
self.log.debug('global_lock acquired')
got_lock = True
if system_state.do_balloon(int(self.data)):
resp = "OK\n"
else:
resp = "FAIL\n"
self.log.debug('resp={!r}'.format(resp))
self.request.send(resp)
except BaseException as e:
self.log.exception(
"exception while handling request: {!r}".format(e))
finally:
if got_lock:
self.log.warning('Second request over qmemman.sock?')
return
self.log.debug('acquiring global_lock')
global_lock.acquire()
self.log.debug('global_lock acquired')
got_lock = True
if system_state.do_balloon(int(self.data)):
resp = "OK\n"
else:
resp = "FAIL\n"
self.log.debug('resp={!r}'.format(resp))
self.request.send(resp)
# XXX no release of lock?
global_lock.release()
self.log.debug('global_lock released')
def start_server(server):