Reported on lkml a flaw that allows you to unlock someone elses ipc memory (hence crossing permission boundary). http://marc.theaimsgroup.com/?l=linux-kernel&m=110132782610477 http://marc.theaimsgroup.com/?l=linux-kernel&m=110137276318105 "In 2.6.8, the only processes that could lock shared memory segments were those with CAP_IPC_LOCK. Unprivileged processes did not get a look in." Looks like this is 2.6.9 (Arjan says since the fixed rhel3 mlock stuff got merged it might be there too)
A fix for this problem has just been committed to the RHEL3 U6 patch pool this evening (in kernel version 2.4.21-32.1.EL).
A fix for this problem has also been committed to the RHEL3 E6 patch pool this evening (in kernel version 2.4.21-32.0.1.EL).
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. http://rhn.redhat.com/errata/RHSA-2005-472.html