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@@ -37,11 +37,12 @@ __setup("vdso=", vdso_setup);
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* of the ELF DSO images included therein.
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*/
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extern const char vsyscall_trapa_start, vsyscall_trapa_end;
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-static void *syscall_page;
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+static struct page *syscall_pages[1];
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int __init vsyscall_init(void)
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{
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- syscall_page = (void *)get_zeroed_page(GFP_ATOMIC);
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+ void *syscall_page = (void *)get_zeroed_page(GFP_ATOMIC);
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+ syscall_pages[0] = virt_to_page(syscall_page);
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/*
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* XXX: Map this page to a fixmap entry if we get around
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@@ -55,37 +56,10 @@ int __init vsyscall_init(void)
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return 0;
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}
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-static struct page *syscall_vma_nopage(struct vm_area_struct *vma,
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- unsigned long address, int *type)
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-{
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- unsigned long offset = address - vma->vm_start;
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- struct page *page;
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-
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- if (address < vma->vm_start || address > vma->vm_end)
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- return NOPAGE_SIGBUS;
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-
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- page = virt_to_page(syscall_page + offset);
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-
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- get_page(page);
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-
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- return page;
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-}
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-
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-/* Prevent VMA merging */
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-static void syscall_vma_close(struct vm_area_struct *vma)
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-{
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-}
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-
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-static struct vm_operations_struct syscall_vm_ops = {
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- .nopage = syscall_vma_nopage,
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- .close = syscall_vma_close,
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-};
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-
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/* Setup a VMA at program startup for the vsyscall page */
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int arch_setup_additional_pages(struct linux_binprm *bprm,
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int executable_stack)
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{
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- struct vm_area_struct *vma;
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struct mm_struct *mm = current->mm;
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unsigned long addr;
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int ret;
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@@ -97,30 +71,16 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
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goto up_fail;
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}
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- vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
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- if (!vma) {
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- ret = -ENOMEM;
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+ ret = install_special_mapping(mm, addr, PAGE_SIZE,
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+ VM_READ | VM_EXEC |
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+ VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC |
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+ VM_ALWAYSDUMP,
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+ syscall_pages);
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+ if (unlikely(ret))
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goto up_fail;
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- }
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-
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- vma->vm_start = addr;
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- vma->vm_end = addr + PAGE_SIZE;
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- /* MAYWRITE to allow gdb to COW and set breakpoints */
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- vma->vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYEXEC|VM_MAYWRITE;
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- vma->vm_flags |= mm->def_flags;
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- vma->vm_page_prot = protection_map[vma->vm_flags & 7];
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- vma->vm_ops = &syscall_vm_ops;
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- vma->vm_mm = mm;
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-
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- ret = insert_vm_struct(mm, vma);
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- if (unlikely(ret)) {
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- kmem_cache_free(vm_area_cachep, vma);
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- goto up_fail;
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- }
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current->mm->context.vdso = (void *)addr;
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- mm->total_vm++;
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up_fail:
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up_write(&mm->mmap_sem);
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return ret;
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