54 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			54 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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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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| 
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| #include <linux/mm.h>
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| #include <asm/elf.h>
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| 
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| static struct vm_area_struct gate_vma;
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| 
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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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| 
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| 	vma_init(&gate_vma, 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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| 
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| 	return 0;
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| }
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| __initcall(gate_vma_init);
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| 
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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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| 
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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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| 
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| 	if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END))
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| 		return 1;
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| 
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| 	return 0;
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| }
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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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| 
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| 	if (!vma)
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| 		return 0;
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| 
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| 	return (addr >= vma->vm_start) && (addr < vma->vm_end);
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| }
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