Description of problem:

sudo shutdown -r +5 fails.  The message saying the system is going down in 5 minutes goes to all of the consoles, but the system does not reboot.  

/var/log/messages gets this message:
Feb 22 03:00:10 s4 systemd-shutdownd[7522]: Received message without credentials. Ignoring.

This message comes from systemd's routine read_packet() which contains:

        if ((n = recvmsg(fd, &msghdr, MSG_DONTWAIT)) <= 0) {
                if (n >= 0) {
                        log_error("Short read");
                        return -EIO;
                }

                if (errno == EAGAIN || errno == EINTR)
                        return 0;

                log_error("recvmsg(): %m");
                return -errno;
        }

        if (msghdr.msg_controllen < CMSG_LEN(sizeof(struct ucred)) ||
            control.cmsghdr.cmsg_level != SOL_SOCKET ||
            control.cmsghdr.cmsg_type != SCM_CREDENTIALS ||
            control.cmsghdr.cmsg_len != CMSG_LEN(sizeof(struct ucred))) {
                log_warning("Received message without credentials.
Ignoring.");
                return 0;
        }

If a socket has the 

SO_PASSCRED

option on, then a control message is supposed to always be set from
which you can pull out the uid and gid.  That's controlled by the kernel
which also got updated at the same time.

Right after this they check to see if the uid is 0 and if not refuse to
shutdown.

Doing a strace of pid 1 while this goes on yields:

open("/sys/fs/cgroup/systemd/system/systemd-shutdownd.service/tasks", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/sys/fs/cgroup/systemd/system/systemd-shutdownd.service", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
sendmsg(14, {msg_name(0)=NULL, msg_iov(2)=[{"l\4\1\1&\0\0\0\1\0\0\0o\0\0\0\1\1o\0\37\0\0\0/org/fre"..., 128}, {"!\0\0\0/system/systemd-shutdownd.se"..., 38}], msg_controllen=0, msg_flags=0}, MSG_NOSIGNAL) = 166

which doesn't look too helpful.



Version-Release number of selected component (if applicable):


How reproducible:

shutdown -r +5


Steps to Reproduce:
1. type sudo shutdown -r +5
2.
3.
  
Actual results:
No reboot

Expected results:
reboot

Additional info:

This started with after a yum update that updated systemd and the kernel:

Feb 12 05:09:27 s3 yum[14291]: Updated: systemd-units-26-16.fc15.x86_64
Feb 12 05:09:28 s3 yum[14291]: Updated: libcurl-7.21.3-13.fc15.x86_64
Feb 12 05:09:29 s3 yum[14291]: Updated: curl-7.21.3-13.fc15.x86_64
Feb 12 05:09:29 s3 yum[14291]: Updated: rpm-libs-4.9.1.2-4.fc15.x86_64
Feb 12 05:09:30 s3 yum[14291]: Updated: rpm-4.9.1.2-4.fc15.x86_64
Feb 12 05:09:31 s3 yum[14291]: Updated: rpm-build-libs-4.9.1.2-4.fc15.x86_64
Feb 12 05:09:31 s3 yum[14291]: Updated: rpm-python-4.9.1.2-4.fc15.x86_64
Feb 12 05:09:32 s3 yum[14291]: Updated: kernel-headers-2.6.42.3-2.fc15.x86_64
Feb 12 05:09:40 s3 yum[14291]: Installed: kernel-2.6.42.3-2.fc15.x86_64
Feb 12 05:09:42 s3 dbus-daemon: [system] Reloaded configuration
Feb 12 05:09:42 s3 dbus-daemon: [system] Reloaded configuration
Feb 12 05:09:43 s3 systemd[1]: Reexecuting.
Feb 12 05:09:44 s3 systemd[1]: systemd 26 running in system mode. (+PAM +LIBWRAP +AUDIT +SELINUX +SYSVINIT +LIBCRYPTSETUP; fedora)
Feb 12 05:09:44 s3 yum[14291]: Updated: systemd-26-16.fc15.x86_64
Feb 12 05:09:45 s3 yum[14291]: Updated: systemd-sysv-26-16.fc15.x86_64
Feb 12 05:09:50 s3 systemd[1]: Reloading.
Feb 12 05:10:45 s3 dbus-daemon: [system] Activating service name='org.freedesktop.PackageKit' (using servicehelper)
Feb 12 05:10:45 s3 dbus-daemon: [system] Successfully activated service 'org.freedesktop.PackageKit'
Feb 12 09:20:30 s3 dbus-daemon: [system] Activating service name='org.freedesktop.PackageKit' (using servicehelper)
Feb 12 09:20:30 s3 dbus-daemon: [system] Successfully activated service 'org.freedesktop.PackageKit'
Feb 12 12:46:23 s3 dbus-daemon: [system] Activating service name='org.freedesktop.PackageKit' (using servicehelper)
Feb 12 12:46:24 s3 dbus-daemon: [system] Successfully activated service 'org.freedesktop.PackageKit'
Feb 13 01:52:49 s3 dbus-daemon: [system] Activating service name='org.freedesktop.PackageKit' (using servicehelper)
Feb 13 01:52:49 s3 dbus-daemon: [system] Successfully activated service 'org.freedesktop.PackageKit'
Feb 13 03:00:01 s3 systemd-shutdownd[2733]: Received message without credentials. Ignoring.
Feb 13 03:15:32 s3 systemd[1]: Reexecuting.
Feb 13 03:15:32 s3 systemd[1]: systemd 26 running in system mode. (+PAM +LIBWRAP +AUDIT +SELINUX +SYSVINIT +LIBCRYPTSETUP; fedora)