•mmap_min_addr forbids users from mapping low addresses 1. First available in July 2007 2. Several circumventions were found 3. Still disabled on many machines •Protects NULL, but not other invalid pointers!     Disallow mapping memory at low address…

今天在编译好内核模块后,安装内核模块memdev.ko的时候,出现了Unable to handle kernel NULL pointer dereference at virtual address 00000000等如图所示的问题: 在百度和google找了很多答案,明显就是跟指针有关系...访问了空指针什么的... 可是代码也有一些怎么找呢?? 于是我想了一个办法,加入打印语句帮助我知道到底哪个函数出了问题! 果然,一下就找到了,如图: 于是,问题就迎刃而解了... 启发链接: http…

本文转载自:https://blog.csdn.net/hpu11/article/details/72628052 这说明是非法指针的使用,才导致系统出错. [ 1023.510000] Unable to handle kernel NULL pointer dereference at virtual address 00000000[ 1023.520000] pgd = c0004000[ 1023.520000] [00000000] *pgd=00000000[ 1023.5200…

Exploit The Linux Kernel NULL Pointer Dereference Author: wztHome: http://hi.baidu.com/wzt85date: 2010/06/13Version: 0.3 目录:1.引言2.NULL Pointer是如何引发OOPS的3.如何Exploit4.攻击实验5.NULL Pointer与Selinux的关系6.如何防御NULL Pointer漏洞7.附录 1.引言在最近一系列的Linux kernel本地溢出漏洞中,…

0x00 漏洞代码 null_dereference.c: #include <linux/init.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/proc_fs.h> void (*my_funptr)(void); int bug1_write(struct file *file, const char *buf, unsigned long len) { m…

// Note: //int x = a[0].GetInt(); // Error: operator[ is ambiguous, as 0 also mean a null pointer of const char* type. int y = a[SizeType(0)].GetInt(); // Cast to SizeType will work. int z = a[0u].GetInt(); // This works too. 0u = SizeType(0)   Json:…

在Joshua Bloch很有名的一本书<Effective in java>中建议不要在代码中返回空的collection/map/array,就像下面的代码一样: public List<String> returnCollection() { //remainder omitted if (/*some condition*/) { return null; } else { // return collection }} 而应该使用下面的模式: public List<…

These are two different concepts, you cannot compare them. What the difference between the skunk and the moonlight? Null pointer is a special reserved value of a pointer. A pointer of any type has such a reserved value. Formally, each specific pointe…

参考: LEETCODE 中的member access within null pointer of type 'struct ListNode' 解决 leetcode 编译问题:Line x: member access within null pointer of type 'struct TreeNode' 在leetcode上提交代码后出现编译错误: Line x: member access within null pointer of type 'struct TreeNode'…

小结: 1.指针的实际值为代表内存地址的16进制数: 2.不同指针的区别是他们指向的变量.常量的类型: https://www.tutorialspoint.com/cprogramming/c_pointers.htm #include <stdio.h>int main(){int var1;char var2[10]; printf("Address of var1 variable: %x\n", &var1);printf("Address of…