55 lines
		
	
	
	
		
			1.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			55 lines
		
	
	
	
		
			1.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
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								/*
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								 * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
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								 *
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								 * This program is free software; you can redistribute it and/or modify
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								 * it under the terms of the GNU General Public License version 2 as
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								 * published by the Free Software Foundation.
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								 */
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								#include <linux/mm.h>
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								#include <asm/page.h>
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								#include <asm/mman.h>
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								static struct vm_area_struct gate_vma;
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								static int __init gate_vma_init(void)
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								{
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									if (!FIXADDR_USER_START)
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										return 0;
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									gate_vma.vm_mm = NULL;
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									gate_vma.vm_start = FIXADDR_USER_START;
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									gate_vma.vm_end = FIXADDR_USER_END;
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									gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
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									gate_vma.vm_page_prot = __P101;
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									return 0;
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								}
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								__initcall(gate_vma_init);
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								struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
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								{
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									return FIXADDR_USER_START ? &gate_vma : NULL;
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								}
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								int in_gate_area_no_mm(unsigned long addr)
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								{
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									if (!FIXADDR_USER_START)
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										return 0;
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									if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END))
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										return 1;
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									return 0;
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								}
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								int in_gate_area(struct mm_struct *mm, unsigned long addr)
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								{
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									struct vm_area_struct *vma = get_gate_vma(mm);
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									if (!vma)
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										return 0;
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									return (addr >= vma->vm_start) && (addr < vma->vm_end);
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								}
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