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PackVmlinuzI386 detects non-relocated kernel

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This commit is contained in:
John Reiser 2008-01-08 09:03:21 -08:00
parent de1c1d7cc2
commit d9073e4a17
1 changed files with 16 additions and 3 deletions
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19
src/p_vmlinz.cpp
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@ -137,9 +137,22 @@ int PackVmlinuzI386::decompressKernel()
char const *p = (char const *)&obuf[setup_size];
for (int j= 0; j < 0x200; ++j, ++p) {
if (0==memcmp("\xE8\x00\x00\x00\x00\x5D", p, 6)) {
/* "call 1f; 1f: pop %ebp" determines actual execution address; */
/* linux-2.6.21 (spring 2007) and later; upx stub needs work. */
throwCantPack("Relocatable kernel is not yet supported");
// "call 1f; 1f: pop %ebp" determines actual execution address.
// linux-2.6.21 (spring 2007) and later; upx stub needs work
// unless LOAD_PHYSICAL_ADDR is known.
// Allowed code is: linux-2.6.23/arch/x86/head_32.S 2008-01-01
// call 1f
// 1: popl %ebp
// subl $1b, %ebp # 32-bit immediate
// movl $LOAD_PHYSICAL_ADDR, %ebx
//
if (0==memcmp("\x81\xed", 6+ p, 2) // subl $imm.w,%ebp
&& 0==memcmp("\xbb", 12+ p, 1) ) { // movl $...,%ebx
physical_start = get_le32(13+ p);
}
else {
throwCantPack("Relocatable kernel is not yet supported");
}
}
// Find "ljmp $__BOOT_CS,$__PHYSICAL_START" if any.
if (0==memcmp("\xEA\x00\x00", p, 3) && 0==(0xf & p[3]) && 0==p[4]) {