crashme - test operating environment software robustness
crashme [NBYTES] [SRAND] [NTRYS] [NSUB] [VERBOSE]
crashme is a very simple program that tests the operating environment’s
robustness by invoking random data as if it were a procedure. The
standard signals are caught and handled with a setjmp back to a loop
which will try again to produce a fault by executing random data. Some
people call this stress testing.
COMMAND LINE OPTIONS
The [NBYTES] should be an integer, specifying the size of the
random data string in bytes. If given negative then the bytes
are printed instead of being executed. If given with an
explicit plus sign then the storage for the bytes is freshly
malloc’ed each time. This can have an effect on machines with
seperate I and D cache mechanisms. The argument can also have a
dot in it, X.Y, in which case Y is a increment for a pointer
into the random data. The buffer is recalculated only when the
pointer gets near the end of the data.
[SRAND] The [SRAND] is an input seed to the random number generator,
passed to srand.
The [NTRIES] is how many times to loop before exiting normally
from the program.
[NSUB] The [NSUB] is optional, the number of vfork subprocesses
running all at once. If negative run one after another. If
given as a time hrs:mns:scs (hours, minutes, seconds) then one
subprocess will be run to completion, followed by another,
until the time limit has been reached. If this argument is
given as the empty string or . then it is ignored.
When in sequential-subprocess mode there is a 30 second time
limit on each subprocess. This is to allow the instruction-set-
space random walk to continue when a process bashes itself into
an infinite loop. For example, the ntrys can be bashed to a
very large number with nbytes bashed to zero. (10 second limit
on Windows NT).
The SRAND argument is incremented by one for each subprocess.
The [VERBOSE] arg is optional. 0 is the least verbose, 5 the
This is a suggested test, to run it for a least an hour.
crashme +2000 666 100 1:00:00
When a signal is caught the number and nature of the signal is
indicated. Setting the environment variable CRASHLOG will cause each
subprocess to record the arguments it was given.
Not all signals are caught, and the state of the user program/process
enviroment can be sufficiently damaged such that the program terminates
before going through all [NTRIES] operations.
If the architecture uses some kind of procedure descriptor but no
special code has been not been added to castaway() in crashme.c then
the stress test will not be as potent as it would otherwise be.
Beware: This program can crash your computer if the operating system or
hardware of same is buggy. User data may be lost.
George J Carrette. GJC@world.std.com