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Fix stack for UPX-compressed kernels via a .sys file; adjust the threshold

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from 64K to the real UPX limit which is 65420.


git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@1333 6ac86273-5f31-0410-b378-82cca8765d1b
This commit is contained in:
Bart Oldeman 2007-05-28 18:45:52 +00:00
parent 5fa8f24fb7
commit 920274e93a
1 changed files with 7 additions and 2 deletions
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9
utils/exeflat.c
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@ -248,7 +248,8 @@ int main(int argc, char **argv)
} }
if (flat_exe) { if (flat_exe) {
compress_sys_file = size < 0x10000L; /* The biggest .sys file that UPX accepts seems to be 65419 bytes long */
compress_sys_file = size < 65420;
if (compress_sys_file && strlen(argv[2]) > 3) if (compress_sys_file && strlen(argv[2]) > 3)
strcpy(argv[2] + strlen(argv[2]) - 3, "sys"); strcpy(argv[2] + strlen(argv[2]) - 3, "sys");
} }
@ -360,10 +361,14 @@ int main(int argc, char **argv)
*(short *)&trailer[1] = (short)size + 0x20; *(short *)&trailer[1] = (short)size + 0x20;
*(short *)&trailer[23] = header.exInitSS; *(short *)&trailer[23] = header.exInitSS;
*(short *)&trailer[28] = header.exInitSP; *(short *)&trailer[28] = header.exInitSP;
if (compress_sys_file) if (compress_sys_file) {
/* replace by jmp word ptr [6]: ff 26 06 00 /* replace by jmp word ptr [6]: ff 26 06 00
(the .SYS strategy handler which will unpack) */ (the .SYS strategy handler which will unpack) */
*(long *)&trailer[30] = 0x000626ffL; *(long *)&trailer[30] = 0x000626ffL;
/* set up a 4K stack for the UPX decompressor to work with */
*(short *)&trailer[23] = 0x1000;
*(short *)&trailer[28] = 0x1000;
}
fwrite(trailer, 1, sizeof trailer, dest); fwrite(trailer, 1, sizeof trailer, dest);
} }
if (flat_exe && compress_sys_file) { if (flat_exe && compress_sys_file) {