Mercurial > sdl-ios-xcode
view src/hermes/x86_main.asm @ 4355:9b464226e541 SDL-1.2
Fixed bug #855
Ludwig Nussel 2009-10-18 06:31:52 PDT
an mprotect call was added to fix bug 528. However that results in a buffer
that allows writing and code execution. Ie the no-execute security features of
modern operating systems are defeated this way. Two mprotect calls are needed.
One to make the buffer executable but not writeable when done and another one
to make the buffer writeable again if the content needs to be changed.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sun, 18 Oct 2009 17:31:37 +0000 |
parents | 540466e900db |
children |
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; ; x86 format converters for HERMES ; Some routines Copyright (c) 1998 Christian Nentwich (brn@eleet.mcb.at) ; This source code is licensed under the GNU LGPL ; ; Please refer to the file COPYING.LIB contained in the distribution for ; licensing conditions ; ; Most routines are (c) Glenn Fiedler (ptc@gaffer.org), used with permission ; BITS 32 %include "common.inc" SDL_FUNC _ConvertX86 SECTION .text ;; _ConvertX86: ;; [ESP+8] ConverterInfo* ;; -------------------------------------------------------------------------- ;; ConverterInfo (ebp+..) ;; 0: void *s_pixels ;; 4: int s_width ;; 8: int s_height ;; 12: int s_add ;; 16: void *d_pixels ;; 20: int d_width ;; 24: int d_height ;; 28: int d_add ;; 32: void (*converter_function)() ;; 36: int32 *lookup _ConvertX86: push ebp mov ebp,esp ; Save the registers used by the blitters, necessary for optimized code pusha mov eax,[ebp+8] cmp dword [eax+4],BYTE 0 je endconvert mov ebp,eax mov esi,[ebp+0] mov edi,[ebp+16] y_loop: mov ecx,[ebp+4] call [ebp+32] add esi,[ebp+12] add edi,[ebp+28] dec dword [ebp+8] jnz y_loop ; Restore the registers used by the blitters, necessary for optimized code popa pop ebp endconvert: ret %ifidn __OUTPUT_FORMAT__,elf section .note.GNU-stack noalloc noexec nowrite progbits %endif