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/*
* Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#include "linux/config.h"
#include "linux/sched.h"
#include "linux/slab.h"
#include "linux/types.h"
#include "asm/uaccess.h"
#include "asm/ptrace.h"
#include "asm/smp.h"
#include "asm/ldt.h"
#include "choose-mode.h"
#include "kern.h"
#include "mode_kern.h"
#ifdef CONFIG_MODE_TT
extern int modify_ldt(int func, void *ptr, unsigned long bytecount);
static int do_modify_ldt_tt(int func, void *ptr, unsigned long bytecount)
{
return modify_ldt(func, ptr, bytecount);
}
#endif
#ifdef CONFIG_MODE_SKAS
#include "skas.h"
#include "skas_ptrace.h"
static int do_modify_ldt_skas(int func, void *ptr, unsigned long bytecount)
{
struct ptrace_ldt ldt;
u32 cpu;
int res;
ldt = ((struct ptrace_ldt) { .func = func,
.ptr = ptr,
.bytecount = bytecount });
cpu = get_cpu();
res = ptrace(PTRACE_LDT, userspace_pid[cpu], 0, (unsigned long) &ldt);
put_cpu();
return res;
}
#endif
int sys_modify_ldt(int func, void __user *ptr, unsigned long bytecount)
{
struct user_desc info;
int res = 0;
void *buf = NULL;
void *p = NULL; /* What we pass to host. */
switch(func){
case 1:
case 0x11: /* write_ldt */
/* Do this check now to avoid overflows. */
if (bytecount != sizeof(struct user_desc)) {
res = -EINVAL;
goto out;
}
if(copy_from_user(&info, ptr, sizeof(info))) {
res = -EFAULT;
goto out;
}
p = &info;
break;
case 0:
case 2: /* read_ldt */
/* The use of info avoids kmalloc on the write case, not on the
* read one. */
buf = kmalloc(bytecount, GFP_KERNEL);
if (!buf) {
res = -ENOMEM;
goto out;
}
p = buf;
default:
res = -ENOSYS;
goto out;
}
res = CHOOSE_MODE_PROC(do_modify_ldt_tt, do_modify_ldt_skas, func,
p, bytecount);
if(res < 0)
goto out;
switch(func){
case 0:
case 2:
/* Modify_ldt was for reading and returned the number of read
* bytes.*/
if(copy_to_user(ptr, p, res))
res = -EFAULT;
break;
}
out:
kfree(buf);
return res;
}
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