Minimal kernel module to quickly introduce kernel crashes for durability testing

kernel_crasher.c

#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>

static char test_buffer[4];
static ssize_t crash_kernel(struct file* _file, const char* _buff, size_t _length, loff_t* _offset) {
  if(_length < 4) {
    return 0;
  }
  if(copy_from_user(test_buffer, _buff, 4)) {
    return -EFAULT;
  }
  if(*((int*)(test_buffer)) != 0xdeadbeef) {
    return 1;
  }
  panic("This is planned!");
}

static const struct proc_ops crasher = {
  .proc_write = crash_kernel,
};

static int __init kernel_crasher_init(void) {
  printk("Creating evil proc file.\n");
  proc_create("PANIC_IF_WRITTEN_TO", 0, NULL, &crasher);
  return 0;
}

static void __exit kernel_crasher_exit(void) {
  printk("Removing evil proc file.\n");
  remove_proc_entry("PANIC_IF_WRITTEN_TO", NULL);
}

MODULE_LICENSE("GPL");
module_init(kernel_crasher_init);
module_exit(kernel_crasher_exit);

Makefile

ifneq ($(KERNELRELEASE),)
obj-m := kernel_crasher.o

else
KDIR := /lib/modules/$(shell uname -r)/build
PWD := $(shell pwd)

default:
	$(MAKE) -C $(KDIR) M=$(PWD) modules
endif