import sys
import os
import setns
+import pdb
from argparse import ArgumentParser
else:
raise Exception('Could not determine architecture')
+def get_cgroup_subdirs_for_pid(pid):
+ cgroup_info_file = '/proc/%s/cgroup'%pid
+ cgroup_lines = open(cgroup_info_file).read().splitlines()
+
+ subdirs = {}
+ for line in cgroup_lines:
+ try:
+ _, cgroup_name, subdir = line.split(':')
+ subdirs[cgroup_name] = subdir
+ except Exception, e:
+ print "Error reading cgroup info: %s"%str(e)
+ pass
+
+ return subdirs
+
+
def umount(fs_dir, opts=''):
output = os.popen('/bin/umount %s %s 2>&1'%(opts, fs_dir)).read()
return ('device is busy' not in output)
def main ():
parser = ArgumentParser()
parser.add_argument("-n", "--nonet",
- action="store_true", dest="netns", default=False,
- help="Don't enter network namespace")
+ action="store_true", dest="no_netns", default=False,
+ help="Don't enter network namespace")
parser.add_argument("-m", "--nomnt",
- action="store_true", dest="mntns", default=False,
- help="Don't enter mount namespace")
+ action="store_true", dest="no_mntns", default=False,
+ help="Don't enter mount namespace")
parser.add_argument("-p", "--nopid",
- action="store_true", dest="pidns", default=False,
- help="Don't enter pid namespace")
+ action="store_true", dest="no_pidns", default=False,
+ help="Don't enter pid namespace")
parser.add_argument("-r", "--root",
- action="store_true", dest="root", default=False,
- help="Enter as root: be careful")
+ action="store_true", dest="root", default=False,
+ help="Enter as root: be careful")
parser.add_argument("-i","--internal",
- action="store_true", dest="internal", default=False,
- help="does *not* prepend '-- -c' to arguments - or invoke lxcsu-internal")
+ action="store_true", dest="internal", default=False,
+ help="does *not* prepend '-- -c' to arguments - or invoke lxcsu-internal")
parser.add_argument("-d","--debug",
- action='store_true', dest='debug', default=False,
- help="debug option")
+ action='store_true', dest='debug', default=False,
+ help="debug option")
parser.add_argument("-s","--nosliceuid",
- action='store_true', dest="nosliceuid", default=False,
- help="do not change to slice uid inside of slice")
+ action='store_true', dest="nosliceuid", default=False,
+ help="do not change to slice uid inside of slice")
parser.add_argument("-o","--noslicehome",
- action='store_true', dest="noslicehome", default=False,
- help="do not change to slice home directory inside of slice")
+ action='store_true', dest="noslicehome", default=False,
+ help="do not change to slice home directory inside of slice")
if os.path.exists("/etc/lxcsu_default"):
defaults = parser.parse_args(file("/etc/lxcsu_default","r").read().split())
# plain lxcsu
if not args.internal:
- # no command given: enter interactive shell
- if not args.command_to_run: args.command_to_run=['/bin/sh']
- args.command_to_run = [ '-c' ] + [" ".join(args.command_to_run)]
+ # no command given: enter interactive shell
+ if not args.command_to_run: args.command_to_run=['/bin/sh']
+ args.command_to_run = [ '-c' ] + [" ".join(args.command_to_run)]
# support for either setting debug at the top of this file, or on the command-line
if args.debug:
global debug
- debug=True
+ debug=True
try:
cmd = '/usr/bin/virsh --connect lxc:/// domid %s'%slice_name
- pidnum = int(os.popen(cmd).read().rstrip())
- except:
- print "Error finding slice %s"%slice_name
- exit(1)
+ # convert to int as a minimal raincheck
+ driver_pid = int(os.popen(cmd).read().strip())
+ # locate the pid for the - expected - single child, that would be the init for that VM
+ #init_pid = int(open("/proc/%s/task/%s/children"%(driver_pid,driver_pid)).read().strip())
+ init_pid = int(os.popen('pgrep -P %s'%driver_pid).readlines()[0].strip())
+ # Thierry: I am changing the code below to use child_pid instead of driver_pid
+ # for the namespace handling features, that I was able to check
+ # I've left the other ones as they were, i.e. using driver_pid, but I suspect
+ # they chould be changed as well
- pid = '%s'%pidnum
- if debug: print "Found pidnum",pidnum
- cmdline = open('/proc/%s/cmdline'%pidnum).read().rstrip('\n\x00')
- arch = getarch('/proc/%s/exe'%pid)
+ except:
+ print "Domain %s not found"%slice_name
+ exit(1)
- if (not pid):
- print "Not started: %s"%slice_name
- exit(1)
+ if not driver_pid or not init_pid:
+ print "Domain %s not started"%slice_name
+ exit(1)
- if arch is None:
- arch = 'x86_64'
+ if debug: print "Found driver_pid",driver_pid,'and init_pid=',init_pid
+ # xxx probably init_pid here too
+ arch = getarch('/proc/%s/exe'%driver_pid)
# Set sysctls specific to slice
sysctls = []
sysctl_dir = '/etc/planetlab/vsys-attributes/%s'%slice_name
if (os.access(sysctl_dir,0)):
entries = os.listdir(sysctl_dir)
- for e in entries:
+ for e in entries:
prefix = 'vsys_sysctl.'
- if (e.startswith(prefix)):
- sysctl_file = '/'.join([sysctl_dir,e])
- sysctl_name = e[len(prefix):]
- sysctl_val = open(sysctl_file).read()
- sysctls.append((sysctl_file, sysctl_name, sysctl_val))
+ if (e.startswith(prefix)):
+ sysctl_file = '/'.join([sysctl_dir,e])
+ sysctl_name = e[len(prefix):]
+ sysctl_val = open(sysctl_file).read()
+ sysctls.append((sysctl_file, sysctl_name, sysctl_val))
- # 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 Exception,e:
- if debug: print e
- 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 Exception,e:
- if debug: print e
- print "Error assigning cpuacct: %s" % slice_name
- exit(1)
+ # xxx probably init_pid here too
+ subdirs = get_cgroup_subdirs_for_pid(driver_pid)
+ sysfs_root = '/sys/fs/cgroup'
# 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 Exception,e:
- if debug: print e
- print "Error adding task to freezer cgroup. Slice is probably frozen: %s" % slice_name
- exit(1)
-
- setns.chcontext('/proc/%s/ns/uts'%pid)
- setns.chcontext('/proc/%s/ns/ipc'%pid)
-
- if (not args.pidns):
- setns.chcontext('/proc/%s/ns/pid'%pid)
-
- if (not args.netns):
- setns.chcontext('/proc/%s/ns/net'%pid)
-
- if (not args.mntns):
- setns.chcontext('/proc/%s/ns/mnt'%pid)
+ # Enter cgroups
+ current_cgroup = ''
+ for subsystem in ['cpuset','memory','blkio','cpuacct','cpuacct,cpu','freezer']:
+ try:
+ current_cgroup = subsystem
+
+ # There seems to be a bug in the cgroup schema: cpuacct,cpu can become cpu,cpuacct
+ # We need to handle both
+ task_path_alt = None
+ try:
+ subsystem_comps = subsystem.split(',')
+ subsystem_comps.reverse()
+ subsystem_alt = ','.join(subsystem_comps)
+ tasks_path_alt = [sysfs_root, subsystem_alt, subdirs[subsystem], 'tasks']
+ except Exception,e:
+ pass
+
+ tasks_path = [sysfs_root,subsystem,subdirs[subsystem],'tasks']
+ tasks_path_str = '/'.join(tasks_path)
+
+ try:
+ f = open(tasks_path_str, 'w')
+ except:
+ tasks_path_alt_str = '/'.join(tasks_path_alt)
+ f = open(tasks_path_alt_str, 'w')
+
+ f.write(str(os.getpid()))
+ if (subsystem=='freezer'):
+ f.close()
+
+ except Exception,e:
+ if (not subdirs.has_key(subsystem)):
+ pass
+ else:
+ if debug: print e
+ print "Error assigning cgroup %s (pid=%s) for slice %s"%(current_cgroup,driver_pid, slice_name)
+ exit(1)
+
+
+ def chcontext (path):
+ retcod = setns.chcontext (path)
+ if retcod != 0:
+ print 'WARNING - setns(%s)=>%s (ignored)'%(path,retcod)
+ return retcod
+
+ # Use init_pid and not driver_pid to locate reference namespaces
+ ref_ns = "/proc/%s/ns/"%init_pid
+
+ if True: chcontext(ref_ns+'uts')
+ if True: chcontext(ref_ns+'ipc')
+
+ if (not args.no_pidns): chcontext(ref_ns+'pid')
+ if (not args.no_netns): chcontext(ref_ns+'net')
+ if (not args.no_mntns): chcontext(ref_ns+'mnt')
proc_mounted = False
if (not os.access('/proc/self',0)):
- proc_mounted = True
- setns.proc_mount()
+ proc_mounted = True
+ setns.proc_mount()
for (sysctl_file, sysctl_name, sysctl_val) in sysctls:
- for fn in ["/sbin/sysctl", "/usr/sbin/sysctl", "/bin/sysctl", "/usr/bin/sysctl"]:
- if os.path.exists(fn):
- os.system('%s -w %s=%s >/dev/null 2>&1'%(fn, sysctl_name,sysctl_val))
- break
- else:
- print "Error: image does not have a sysctl binary"
+ for fn in ["/sbin/sysctl", "/usr/sbin/sysctl", "/bin/sysctl", "/usr/bin/sysctl"]:
+ if os.path.exists(fn):
+ os.system('%s -w %s=%s >/dev/null 2>&1'%(fn, sysctl_name,sysctl_val))
+ break
+ else:
+ print "Error: image does not have a sysctl binary"
# cgroups is not yet LXC-safe, so we need to use the coarse 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','systemd']:
- fs_path = '/sys/fs/cgroup/%s'%subsystem
- if (not umount(fs_path,'-l')):
- pass
- # Leaving these comments for historical reference
- #print "Error disabling cgroup access"
- #exit(1) - Don't need this because failure here implies failure in the call to umount /sys/fs/cgroup
+ fs_path = '/sys/fs/cgroup/%s'%subsystem
+ if (not umount(fs_path,'-l')):
+ print 'WARNING - umount failed (ignored) with path=',fs_path
+ pass
+ # Leaving these comments for historical reference
+ #print "Error disabling cgroup access"
+ #exit(1) - Don't need this because failure here implies failure in the call to umount /sys/fs/cgroup
if (not umount('/sys/fs/cgroup')):
print "Error disabling cgroup access"
exit(1)
- pid = os.fork()
+ fork_pid = os.fork()
# capsh has a --user option starting with f14
# so if only for f12 we need to fake this one
#
# capsh.c does essentially the following when invoked with --user:
- # pwd = getpwnam(user); ...
- # ngroups = MAX_GROUPS;
- # status = getgrouplist(user, pwd->pw_gid, groups, &ngroups); ...
- # status = setgroups(ngroups, groups); ...
- # status = setgid(pwd->pw_gid); ...
- # status = setuid(pwd->pw_uid); ...
+ # pwd = getpwnam(user); ...
+ # ngroups = MAX_GROUPS;
+ # status = getgrouplist(user, pwd->pw_gid, groups, &ngroups); ...
+ # status = setgroups(ngroups, groups); ...
+ # status = setgid(pwd->pw_gid); ...
+ # status = setuid(pwd->pw_uid); ...
# however we cannot simulate that ourselves because if we did in this process then
# capsh could not be allowed to mess with caps any more
except:
return
- if (pid == 0):
+ if (fork_pid == 0):
cap_arg = '--drop='+drop_capabilities
if (not args.root):
os.execv('/usr/bin/setarch',exec_args)
else:
setns.proc_umount()
- _,status = os.waitpid(pid,0)
+ _,status = os.waitpid(fork_pid,0)
exit(os.WEXITSTATUS(status))
if __name__ == '__main__':
- main()
+ main()
git://git.onelab.eu / lxc-userspace.git / blobdiff