Reported to vendor-sec from the kernel security list, originally from Georgi
"It is possible to partially overwrite low kernel memory due to integer overflow
in sys_epoll_wait and misuse of __put_user in ep_send_events"
Note that this area usually doesn't actually contain anything (the first 4kB are
left alone for dosemu etc to read the original 16-bit interrupt descriptors, and
the rest is just about the last thing we ever allocate, so it's usually unused)
Fixed upstream, see
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.