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A module for playing with kernel NULL pointer dereferences
Branch: master

Update Makefile

Every system I've seen has the /build symlink but not the /source symlink.
latest commit fade3ab9ff
@nelhage authored


NULLDEREF -- A module for playing with kernel NULL pointer dereferences

This module should build against any remotely recent 2.6 kernel. To
build, you'll need the kernel headers for your kernel installed. On
Debian or Ubuntu, try:
 # apt-get install linux-headers-$(uname -r)
on Fedora, try:
 # yum install kernel-devel

Once you've got those, just run 'make' to produce a 'nullderef.ko'


nullderef uses sysfs to export its hooks. Simply
 # insmod nullderef.ko

You shuld now have a /sys/module/nullderef/parameters/ directory,
containing two files, "read", and "call".

Reading from either of these files will result in a NULL pointer
dereference in the kernel. "read" will simply try to read a NULL
pointer. "call" will read a function pointer from the NULL address,
and then attempt to call through the resulting pointer.

Once you're done crashing your kernel, if your machine is still
stable, you can remove the module using:
 # rmmod nullderef
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