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-rw-r--r--arch/i386/mm/mprotect.c230
1 files changed, 0 insertions, 230 deletions
diff --git a/arch/i386/mm/mprotect.c b/arch/i386/mm/mprotect.c
deleted file mode 100644
index 99252183b..000000000
--- a/arch/i386/mm/mprotect.c
+++ /dev/null
@@ -1,230 +0,0 @@
-/*
- * linux/mm/mprotect.c
- *
- * (C) Copyright 1994 Linus Torvalds
- */
-#include <linux/stat.h>
-#include <linux/sched.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/shm.h>
-#include <linux/errno.h>
-#include <linux/mman.h>
-#include <linux/string.h>
-#include <linux/malloc.h>
-
-#include <asm/segment.h>
-#include <asm/system.h>
-
-#define CHG_MASK (PAGE_MASK | PAGE_ACCESSED | PAGE_DIRTY | PAGE_PWT | PAGE_PCD)
-
-static void change_protection(unsigned long start, unsigned long end, int prot)
-{
- unsigned long *page_table, *dir;
- unsigned long page, offset;
- int nr;
-
- dir = PAGE_DIR_OFFSET(current->tss.cr3, start);
- offset = (start >> PAGE_SHIFT) & (PTRS_PER_PAGE-1);
- nr = (end - start) >> PAGE_SHIFT;
- while (nr > 0) {
- page = *dir;
- dir++;
- if (!(page & PAGE_PRESENT)) {
- nr = nr - PTRS_PER_PAGE + offset;
- offset = 0;
- continue;
- }
- page_table = offset + (unsigned long *) (page & PAGE_MASK);
- offset = PTRS_PER_PAGE - offset;
- if (offset > nr)
- offset = nr;
- nr = nr - offset;
- do {
- page = *page_table;
- if (page & PAGE_PRESENT)
- *page_table = (page & CHG_MASK) | prot;
- ++page_table;
- } while (--offset);
- }
- return;
-}
-
-static inline int mprotect_fixup_all(struct vm_area_struct * vma,
- int newflags, int prot)
-{
- vma->vm_flags = newflags;
- vma->vm_page_prot = prot;
- return 0;
-}
-
-static inline int mprotect_fixup_start(struct vm_area_struct * vma,
- unsigned long end,
- int newflags, int prot)
-{
- struct vm_area_struct * n;
-
- n = (struct vm_area_struct *) kmalloc(sizeof(struct vm_area_struct), GFP_KERNEL);
- if (!n)
- return -ENOMEM;
- *n = *vma;
- vma->vm_start = end;
- n->vm_end = end;
- vma->vm_offset += vma->vm_start - n->vm_start;
- n->vm_flags = newflags;
- n->vm_page_prot = prot;
- if (n->vm_inode)
- n->vm_inode->i_count++;
- if (n->vm_ops && n->vm_ops->open)
- n->vm_ops->open(n);
- insert_vm_struct(current, n);
- return 0;
-}
-
-static inline int mprotect_fixup_end(struct vm_area_struct * vma,
- unsigned long start,
- int newflags, int prot)
-{
- struct vm_area_struct * n;
-
- n = (struct vm_area_struct *) kmalloc(sizeof(struct vm_area_struct), GFP_KERNEL);
- if (!n)
- return -ENOMEM;
- *n = *vma;
- vma->vm_end = start;
- n->vm_start = start;
- n->vm_offset += n->vm_start - vma->vm_start;
- n->vm_flags = newflags;
- n->vm_page_prot = prot;
- if (n->vm_inode)
- n->vm_inode->i_count++;
- if (n->vm_ops && n->vm_ops->open)
- n->vm_ops->open(n);
- insert_vm_struct(current, n);
- return 0;
-}
-
-static inline int mprotect_fixup_middle(struct vm_area_struct * vma,
- unsigned long start, unsigned long end,
- int newflags, int prot)
-{
- struct vm_area_struct * left, * right;
-
- left = (struct vm_area_struct *) kmalloc(sizeof(struct vm_area_struct), GFP_KERNEL);
- if (!left)
- return -ENOMEM;
- right = (struct vm_area_struct *) kmalloc(sizeof(struct vm_area_struct), GFP_KERNEL);
- if (!right) {
- kfree(left);
- return -ENOMEM;
- }
- *left = *vma;
- *right = *vma;
- left->vm_end = start;
- vma->vm_start = start;
- vma->vm_end = end;
- right->vm_start = end;
- vma->vm_offset += vma->vm_start - left->vm_start;
- right->vm_offset += right->vm_start - left->vm_start;
- vma->vm_flags = newflags;
- vma->vm_page_prot = prot;
- if (vma->vm_inode)
- vma->vm_inode->i_count += 2;
- if (vma->vm_ops && vma->vm_ops->open) {
- vma->vm_ops->open(left);
- vma->vm_ops->open(right);
- }
- insert_vm_struct(current, left);
- insert_vm_struct(current, right);
- return 0;
-}
-
-static int mprotect_fixup(struct vm_area_struct * vma,
- unsigned long start, unsigned long end, unsigned int newflags)
-{
- int prot, error;
-
- if (newflags == vma->vm_flags)
- return 0;
- prot = PAGE_PRESENT;
- if (newflags & (VM_READ | VM_EXEC))
- prot |= PAGE_READONLY;
- if (newflags & VM_WRITE)
- if (newflags & VM_SHARED)
- prot |= PAGE_SHARED;
- else
- prot |= PAGE_COPY;
-
- if (start == vma->vm_start)
- if (end == vma->vm_end)
- error = mprotect_fixup_all(vma, newflags, prot);
- else
- error = mprotect_fixup_start(vma, end, newflags, prot);
- else if (end == vma->vm_end)
- error = mprotect_fixup_end(vma, start, newflags, prot);
- else
- error = mprotect_fixup_middle(vma, start, end, newflags, prot);
-
- if (error)
- return error;
-
- change_protection(start, end, prot);
- return 0;
-}
-
-asmlinkage int sys_mprotect(unsigned long start, size_t len, unsigned long prot)
-{
- unsigned long end, tmp;
- struct vm_area_struct * vma, * next;
- int error;
-
- if (start & ~PAGE_MASK)
- return -EINVAL;
- len = (len + ~PAGE_MASK) & PAGE_MASK;
- end = start + len;
- if (end < start)
- return -EINVAL;
- if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC))
- return -EINVAL;
- if (end == start)
- return 0;
- for (vma = current->mm->mmap ; ; vma = vma->vm_next) {
- if (!vma)
- return -EFAULT;
- if (vma->vm_end > start)
- break;
- }
- if (vma->vm_start > start)
- return -EFAULT;
-
- for ( ; ; ) {
- unsigned int newflags;
-
- /* Here we know that vma->vm_start <= start < vma->vm_end. */
-
- newflags = prot | (vma->vm_flags & ~(PROT_READ | PROT_WRITE | PROT_EXEC));
- if ((newflags & ~(newflags >> 4)) & 0xf) {
- error = -EACCES;
- break;
- }
-
- if (vma->vm_end >= end) {
- error = mprotect_fixup(vma, start, end, newflags);
- break;
- }
-
- tmp = vma->vm_end;
- next = vma->vm_next;
- error = mprotect_fixup(vma, start, tmp, newflags);
- if (error)
- break;
- start = tmp;
- vma = next;
- if (!vma || vma->vm_start != start) {
- error = -EFAULT;
- break;
- }
- }
- merge_segments(current->mm->mmap);
- return error;
-}
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