Using asynchronous IO on a FIFO causes RHEL 3U9 to kernel panic. (Does not occur in RHEL 4 as the pipe_write function has been re-written) This is a security issue because a local unprivileged user can cause a kernel panic. Reproducer in bz#311621
This issue posted on 2008-06-05 to upstream security list. Reviewed and confirmed by Don Howard and Josef Bacik, this issue not present in upstream vanilla 2.4.21 kernel -> lifting the embargo for this one.
This was addressed via: Red Hat Enterprise Linux version 3 (RHSA-2008:0211)