import setns
import os
+import sys
-from optparse import OptionParser
+#from optparse import OptionParser
-drop_capabilities='cap_sys_admin,cap_net_admin,cap_sys_boot,cap_sys_module'.split(',')
+drop_capabilities='cap_sys_admin,cap_sys_boot,cap_sys_module'
+def umount(fs_dir):
+ output = os.popen('/bin/umount %s 2>&1'%fs_dir).read()
+ return ('device is busy' not in fs_dir)
+
+
+"""
parser = OptionParser()
parser.add_option("-n", "--net",
action="store_true", dest="netns", default=False,
help="Enter pid namespace")
(options, args) = parser.parse_args()
+"""
+args = sys.argv[1:]
try:
slice_name = args[0]
print "Not started: %s"%slice_name
exit(1)
-r1 = setns.chcontext('/proc/%s/ns/utc'%pid)
+# Enter cgroups
+try:
+ for subsystem in ['cpuset','memory','blkio']:
+ open('/sys/fs/cgroup/%s/libvirt/lxc/%s/tasks'%(subsystem,slice_name),'w').write(str(os.getpid()))
+
+except:
+ print "Error assigning resources: %s"%slice_name
+ exit(1)
+
+try:
+ open('/sys/fs/cgroup/cpuacct/system/libvirtd.service/libvirt/lxc/%s/tasks'%slice_name,'w').write(str(os.getpid()))
+except:
+ print "Error assigning cpuacct: %s" % slice_name
+ exit(1)
+
+# If the slice is frozen, then we'll get an EBUSY when trying to write to the task
+# list for the freezer cgroup. Since the user couldn't do anything anyway, it's best
+# in this case to error out the shell. (an alternative would be to un-freeze it,
+# add the task, and re-freeze it)
+try:
+ f=open('/sys/fs/cgroup/freezer/libvirt/lxc/%s/tasks'%(slice_name),'w')
+ f.write(str(os.getpid()))
+ # note: we need to call f.close() explicitly, or we'll get an exception in
+ # the object destructor, which will not be caught
+ f.close()
+except:
+ print "Error adding task to freezer cgroup. Slice is probably frozen: %s" % slice_name
+ exit(1)
+
+r1 = setns.chcontext('/proc/%s/ns/uts'%pid)
r2 = setns.chcontext('/proc/%s/ns/ipc'%pid)
-path = '/proc/%s/ns/net'%pid
-r3 = setns.chcontext(path)
+r3 = setns.chcontext('/proc/%s/ns/net'%pid)
open('/proc/lxcsu','w').write(pid)
open('/proc/pidsu','w').write(pid)
+# cgroups is not yet LXC-safe, so we need to use the course grained access control
+# strategy of unmounting the filesystem
+
+umount_result = True
+for subsystem in ['cpuset','cpu,cpuacct','memory','devices','freezer','net_cls','blkio','perf_event']:
+ fs_path = '/sys/fs/cgroup/%s'%subsystem
+ if (not umount(fs_path)):
+ print "Error disabling cgroup access"
+ exit(1)
+
+if (not umount('/sys/fs/cgroup')):
+ print "Error disabling cgroup access"
+ exit(1)
+
pid = os.fork()
-cap_args = map(lambda c:'--drop='+c, drop_capabilities)
-
if (pid == 0):
- os.execv('/usr/sbin/capsh',cap_args+['--'])
+ cap_arg = '--drop='+drop_capabilities
+ exec_args = ['/usr/sbin/capsh',cap_arg,'--','--login']+args[1:]
+
+ os.environ['SHELL'] = '/bin/sh'
+ os.execv('/usr/sbin/capsh',exec_args)
else:
- os.waitpid(pid,0)
+ (r_pid,combined)=os.waitpid(pid,0)
+ retcod=combined/256
+ sys.exit(retcod)
+