内核是根据 linux-5.6.13 的源码自己编译的内核,虚拟机+Centos7 64 位

代码如下

#include <linux/init.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/unistd.h> #include <asm/uaccess.h> #include <linux/sched.h> #define my_syscall_num 336 /*此处我也不知道为啥，执行 cat /proc/kallsyms | grep sys_call_table 结果如下 0000000000000000 R sys_call_table 0000000000000000 R ia32_sys_call_table */ #define sys_call_table_adress 0x00000000 unsigned int clear_and_return_cr0(void); void setback_cr0(unsigned int val); asmlinkage long sys_mycall(long long num); int orig_cr0; unsigned long *sys_call_table = 0; static int (*anything_saved)(void); MODULE_AUTHOR("GuoShuSong"); MODULE_LICENSE("GPL"); unsigned int clear_and_return_cr0(void){ unsigned int cr0 = 0; unsigned int ret; asm("movl %%cr0,%%eax":"=a"(cr0)); ret = cr0; cr0 &= 0xfffeffff; asm("movl %%eax,%%cr0"::"a"(cr0)); return ret; } void setback_cr0(unsigned int val){ asm volatile("movl %%eax,%%cr0"::"a"(val)); } static int __init init_addsyscall(void){ printk("hello,kernel"); sys_call_table=(unsigned long *)sys_call_table_adress; anything_saved = (int(*)(void))(sys_call_table[my_syscall_num]); orig_cr0 = clear_and_return_cr0(); sys_call_table[my_syscall_num]= (unsigned long)&sys_mycall; setback_cr0(orig_cr0); return 0; } asmlinkage long sys_mycall(long long num){ int res =0; long long r = num; if(do_div(num,2)== 0){ res = do_div(r,1000000); }else{ res = do_div(r,100000); } return res; } static void __exit exit_addsyscall(void){ orig_cr0 = clear_and_return_cr0(); sys_call_table[my_syscall_num]= (unsigned long)anything_saved; setback_cr0(orig_cr0); printk("call exit \n"); } module_init(init_addsyscall); module_exit(exit_addsyscall); 

MakeFile 代码如下

ifneq ($(KERNELRELEASE),) EXTRA_CFLAGS = -O0 obj-m := gss.o else KDIR = /lib/modules/$(shell uname -r)/build #KDIR = /lib/modules/5.6.1318130500093-GuoShuSong/build PWD := $(shell pwd) all: make -C $(KDIR) M=$(PWD) modules clean: rm -f *.ko *.o *.symvers *.cmd *.cmd.o endif 

执行 make 时报错如下

make -C /lib/modules/5.6.1318130500093-GuoShuSong/build M=/home/gssplus/桌面 /test/os3 modules make[1]: 进入目录“/home/gssplus/桌面 /test/linux-5.6.13” CC [M] /home/gssplus/桌面 /test/os3/gss.o In file included from /home/gssplus/桌面 /test/os3/gss.c:5:0: ./arch/x86/include/asm/uaccess.h: 在函数‘set_fs’中: ./arch/x86/include/asm/uaccess.h:31:9: 错误：提领指向不完全类型的指针 current->thread.addr_limit = fs; ^ In file included from ./include/linux/init.h:5:0, from /home/gssplus/桌面 /test/os3/gss.c:1: ./arch/x86/include/asm/uaccess.h: 在函数‘user_access_begin’中: ./arch/x86/include/asm/uaccess.h:37:33: 错误：提领指向不完全类型的指针 #define user_addr_max() (current->thread.addr_limit.seg) ^ ./include/linux/compiler.h:78:42: 附注：in definition of macro ‘unlikely’ # define unlikely(x) __builtin_expect(!!(x), 0) ^ ./arch/x86/include/asm/uaccess.h:96:2: 附注：in expansion of macro ‘likely’ likely(!__range_not_ok(addr, size, user_addr_max())); \ ^ ./arch/x86/include/asm/uaccess.h:96:10: 附注：in expansion of macro ‘__range_not_ok’ likely(!__range_not_ok(addr, size, user_addr_max())); \ ^ ./arch/x86/include/asm/uaccess.h:96:37: 附注：in expansion of macro ‘user_addr_max’ likely(!__range_not_ok(addr, size, user_addr_max())); \ ^ ./arch/x86/include/asm/uaccess.h:714:16: 附注：in expansion of macro ‘access_ok’ if (unlikely(!access_ok(ptr,len))) ^ make[3]: *** [/home/gssplus/桌面 /test/os3/gss.o] 错误 1 make[2]: *** [/home/gssplus/桌面 /test/os3] 错误 2 make[1]: *** [sub-make] 错误 2 make[1]: 离开目录“/home/gssplus/桌面 /test/linux-5.6.13” make: *** [all] 错误 2 

有没有大佬知道是怎么回事儿