arch/um/sys-i386/ldt.c

   1 /*
   2  * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include "linux/config.h"
   7 #include "linux/slab.h"
   8 #include "asm/uaccess.h"
   9 #include "asm/ptrace.h"
  10 #include "choose-mode.h"
  11 #include "kern.h"
  12
  13 #ifdef CONFIG_MODE_TT
  14 extern int modify_ldt(int func, void *ptr, unsigned long bytecount);
  15
  16 /* XXX this needs copy_to_user and copy_from_user */
  17
  18 int sys_modify_ldt_tt(int func, void __user *ptr, unsigned long bytecount)
  19 {
  20         if (!access_ok(VERIFY_READ, ptr, bytecount))
  21                 return -EFAULT;
  22
  23         return modify_ldt(func, ptr, bytecount);
  24 }
  25 #endif
  26
  27 #ifdef CONFIG_MODE_SKAS
  28 extern int userspace_pid;
  29
  30 #include "skas_ptrace.h"
  31
  32 int sys_modify_ldt_skas(int func, void __user *ptr, unsigned long bytecount)
  33 {
  34         struct ptrace_ldt ldt;
  35         void *buf;
  36         int res, n;
  37
  38         buf = kmalloc(bytecount, GFP_KERNEL);
  39         if(buf == NULL)
  40                 return(-ENOMEM);
  41
  42         res = 0;
  43
  44         switch(func){
  45         case 1:
  46         case 0x11:
  47                 res = copy_from_user(buf, ptr, bytecount);
  48                 break;
  49         }
  50
  51         if(res != 0){
  52                 res = -EFAULT;
  53                 goto out;
  54         }
  55
  56         ldt = ((struct ptrace_ldt) { .func      = func,
  57                                      .ptr       = buf,
  58                                      .bytecount = bytecount });
  59         res = ptrace(PTRACE_LDT, userspace_pid, 0, (unsigned long) &ldt);
  60         if(res < 0)
  61                 goto out;
  62
  63         switch(func){
  64         case 0:
  65         case 2:
  66                 n = res;
  67                 res = copy_to_user(ptr, buf, n);
  68                 if(res != 0)
  69                         res = -EFAULT;
  70                 else
  71                         res = n;
  72                 break;
  73         }
  74
  75  out:
  76         kfree(buf);
  77         return(res);
  78 }
  79 #endif
  80
  81 int sys_modify_ldt(int func, void __user *ptr, unsigned long bytecount)
  82 {
  83         return(CHOOSE_MODE_PROC(sys_modify_ldt_tt, sys_modify_ldt_skas, func,
  84                                 ptr, bytecount));
  85 }
  86
  87
  88
  89 /*
  90  * Overrides for Emacs so that we follow Linus's tabbing style.
  91  * Emacs will notice this stuff at the end of the file and automatically
  92  * adjust the settings for this buffer only.  This must remain at the end
  93  * of the file.
  94  * ---------------------------------------------------------------------------
  95  * Local variables:
  96  * c-file-style: "linux"
  97  * End:
  98  */