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Diffstat (limited to 'arch/ia64/ia32/ia32_ldt.c')
-rw-r--r--arch/ia64/ia32/ia32_ldt.c146
1 files changed, 0 insertions, 146 deletions
diff --git a/arch/ia64/ia32/ia32_ldt.c b/arch/ia64/ia32/ia32_ldt.c
deleted file mode 100644
index 16d51c146849..000000000000
--- a/arch/ia64/ia32/ia32_ldt.c
+++ /dev/null
@@ -1,146 +0,0 @@
-/*
- * Copyright (C) 2001, 2004 Hewlett-Packard Co
- * David Mosberger-Tang <davidm@hpl.hp.com>
- *
- * Adapted from arch/i386/kernel/ldt.c
- */
-
-#include <linux/errno.h>
-#include <linux/sched.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/smp.h>
-#include <linux/vmalloc.h>
-
-#include <asm/uaccess.h>
-
-#include "ia32priv.h"
-
-/*
- * read_ldt() is not really atomic - this is not a problem since synchronization of reads
- * and writes done to the LDT has to be assured by user-space anyway. Writes are atomic,
- * to protect the security checks done on new descriptors.
- */
-static int
-read_ldt (void __user *ptr, unsigned long bytecount)
-{
- unsigned long bytes_left, n;
- char __user *src, *dst;
- char buf[256]; /* temporary buffer (don't overflow kernel stack!) */
-
- if (bytecount > IA32_LDT_ENTRIES*IA32_LDT_ENTRY_SIZE)
- bytecount = IA32_LDT_ENTRIES*IA32_LDT_ENTRY_SIZE;
-
- bytes_left = bytecount;
-
- src = (void __user *) IA32_LDT_OFFSET;
- dst = ptr;
-
- while (bytes_left) {
- n = sizeof(buf);
- if (n > bytes_left)
- n = bytes_left;
-
- /*
- * We know we're reading valid memory, but we still must guard against
- * running out of memory.
- */
- if (__copy_from_user(buf, src, n))
- return -EFAULT;
-
- if (copy_to_user(dst, buf, n))
- return -EFAULT;
-
- src += n;
- dst += n;
- bytes_left -= n;
- }
- return bytecount;
-}
-
-static int
-read_default_ldt (void __user * ptr, unsigned long bytecount)
-{
- unsigned long size;
- int err;
-
- /* XXX fix me: should return equivalent of default_ldt[0] */
- err = 0;
- size = 8;
- if (size > bytecount)
- size = bytecount;
-
- err = size;
- if (clear_user(ptr, size))
- err = -EFAULT;
-
- return err;
-}
-
-static int
-write_ldt (void __user * ptr, unsigned long bytecount, int oldmode)
-{
- struct ia32_user_desc ldt_info;
- __u64 entry;
- int ret;
-
- if (bytecount != sizeof(ldt_info))
- return -EINVAL;
- if (copy_from_user(&ldt_info, ptr, sizeof(ldt_info)))
- return -EFAULT;
-
- if (ldt_info.entry_number >= IA32_LDT_ENTRIES)
- return -EINVAL;
- if (ldt_info.contents == 3) {
- if (oldmode)
- return -EINVAL;
- if (ldt_info.seg_not_present == 0)
- return -EINVAL;
- }
-
- if (ldt_info.base_addr == 0 && ldt_info.limit == 0
- && (oldmode || (ldt_info.contents == 0 && ldt_info.read_exec_only == 1
- && ldt_info.seg_32bit == 0 && ldt_info.limit_in_pages == 0
- && ldt_info.seg_not_present == 1 && ldt_info.useable == 0)))
- /* allow LDTs to be cleared by the user */
- entry = 0;
- else
- /* we must set the "Accessed" bit as IVE doesn't emulate it */
- entry = IA32_SEG_DESCRIPTOR(ldt_info.base_addr, ldt_info.limit,
- (((ldt_info.read_exec_only ^ 1) << 1)
- | (ldt_info.contents << 2)) | 1,
- 1, 3, ldt_info.seg_not_present ^ 1,
- (oldmode ? 0 : ldt_info.useable),
- ldt_info.seg_32bit,
- ldt_info.limit_in_pages);
- /*
- * Install the new entry. We know we're accessing valid (mapped) user-level
- * memory, but we still need to guard against out-of-memory, hence we must use
- * put_user().
- */
- ret = __put_user(entry, (__u64 __user *) IA32_LDT_OFFSET + ldt_info.entry_number);
- ia32_load_segment_descriptors(current);
- return ret;
-}
-
-asmlinkage int
-sys32_modify_ldt (int func, unsigned int ptr, unsigned int bytecount)
-{
- int ret = -ENOSYS;
-
- switch (func) {
- case 0:
- ret = read_ldt(compat_ptr(ptr), bytecount);
- break;
- case 1:
- ret = write_ldt(compat_ptr(ptr), bytecount, 1);
- break;
- case 2:
- ret = read_default_ldt(compat_ptr(ptr), bytecount);
- break;
- case 0x11:
- ret = write_ldt(compat_ptr(ptr), bytecount, 0);
- break;
- }
- return ret;
-}