COMMAND
MILO
SYSTEMS AFFECTED
Linux RedHat 5.x (Alpha)
PROBLEM
Following is based on KSR[T] Security Advisory. Any local user
can cause an Alpha Linux machine to reboot, lock up or become
unstable. During the beta-testing of an instruction set auditor,
the KSR[T] team found several instructions that caused an Alpha
Linux machine to generate an 'Oops' or to reboot/hang. This
involves the call_pal instruction with different immediate
arguments. The PALcode currently used in the MILO that comes
with Redhat 5.x and below has two additional debugging PAL calls,
DBGSTOP (0xAD) and NPHALT (0xBF). NPHALT is a non-privileged HALT
instruction, which brings the machine straight back to the console
even from user space. These calls were used during the
development of MILO and were not intended for production use.
SOLUTION
The copies of MILO distributed at:
ftp://genie.ucd.ie/pub/alpha/milo/milo-latest
are not vulnerable to this attack.