The workaround for boinc is not to use schedtool's SCHED_IDLEPRIO:
Edit /etc/default/boinc-client and set to SCHEDULE="0". E.g.
echo SCHEDULE="0"|sudo tee /etc/default/boinc-client
You can also deinstall schedtool and ionice for now, though that won't fix the security issue. Affected Systems include Ubuntu Server 8.04 with all updates. But many other systems are likely affected if the fix has not yet been backported (fixed in 2.6.29).