kernel_crash_module_20ways.c

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/slab.h>

static char *crash_type = "null";
module_param(crash_type, charp, S_IRUGO | S_IWUSR);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Your Name <your_email@example.com>");
MODULE_DESCRIPTION("Kernel crasher module");

static void crash_null_pointer(void) {
    int *ptr = NULL;
    *ptr = 0;
}

static void crash_divide_by_zero(void) {
    int a = 1, b = 0;
    a = a / b;
}

static void crash_stack_overflow(void) {
    char buf[1024];
    memset(buf, 0, 1024);
    crash_stack_overflow();
}

static void crash_buffer_overflow(void) {
    char *buf = kmalloc(8, GFP_KERNEL);
    strcpy(buf, "1234567890123456789012345678901234567890");
}

static void crash_page_fault(void) {
    asm volatile("movl $0x0, (0x0)");
}

static void crash_general_protection_fault(void) {
    asm volatile("int $0x0");
}

static void crash_invalid_opcode(void) {
    asm volatile(".byte 0xff");
}

static void crash_out_of_memory(void) {
    while (1) {
        kmalloc(-1, GFP_KERNEL);
    }
}

static void crash_null_function_pointer(void) {
    void (*func)(void) = NULL;
    func();
}

static void crash_bad_function_pointer(void) {
    void (*func)(void) = (void (*)(void))0xffffffff;
    func();
}

static void crash_uninitialized_variable(void) {
    int a;
    printk(KERN_INFO "%d\n", a);
}

static void crash_use_after_free(void) {
    char *buf = kmalloc(8, GFP_KERNEL);
    kfree(buf);
    printk(KERN_INFO "%c\n", buf[0]);
}

static void crash_divide_by_random_number(void) {
    int a = 1, b = prandom_u32();
    a = a / b;
}

static void crash_use_uninitialized_pointer(void) {
    int *ptr;
    printk(KERN_INFO "%d\n", *ptr);
}

static void crash_interrupt_kernel(void) {
    local_irq_disable();
}

static void crash_call_user_function(void) {
    void (*user_function)(void);
    user_function = (void (*)(void))0xc0000000;
    user_function();
}

static void crash_corrupted_kernel_data(void) {
    char *buf = (char *)0xc0000000;
    *buf = 'a';
}

static void crash_null_system_call(void) {
    asm volatile("int $0x80");
}

static void crash_kernel_panic(void) {
    panic("kernel_panic");
}

static void crash_hung_task(void) {
    while (1) {
        schedule();
    }
}

static int __init crash_init(void)
{
    printk(KERN_INFO "Crasher module loaded\n");

    if (strcmp(crash_type, "null") == 0) {
        crash_null_pointer();
    } else if (strcmp(crash_type, "divide_by_zero") == 0) {
        crash_divide_by_zero();
    } else if (strcmp(crash_type, "stack_overflow") == 0) {
        crash_stack_overflow();
    } else if (strcmp(crash_type, "buffer_overflow") == 0) {
        crash_buffer_overflow();
    } else if (strcmp(crash_type
...
}