Index: /trunk/src/VBox/ValidationKit/bootsectors/bs3kit/VBoxBs3ObjConverter.cpp =================================================================== --- /trunk/src/VBox/ValidationKit/bootsectors/bs3kit/VBoxBs3ObjConverter.cpp (revision 59899) +++ /trunk/src/VBox/ValidationKit/bootsectors/bs3kit/VBoxBs3ObjConverter.cpp (revision 59900) @@ -35,4 +35,5 @@ #include #include +#include #include @@ -319,4 +320,16 @@ }; + +static const char *coffGetSymbolName(PCIMAGE_SYMBOL pSym, const char *pchStrTab, char pszShortName[16]) +{ + if (pSym->N.Name.Short != 0) + { + memcpy(pszShortName, pSym->N.ShortName, 8); + pszShortName[8] = '\0'; + return pszShortName; + } + return pchStrTab + pSym->N.Name.Long; +} + static bool convertcoff(const char *pszFile, uint8_t *pbFile, size_t cbFile) { @@ -342,4 +355,17 @@ } + /* Dump the symbol table if verbose mode. */ + PIMAGE_SYMBOL paSymTab = (PIMAGE_SYMBOL)&pbFile[pHdr->PointerToSymbolTable]; + const char *pchStrTab = (const char *)&paSymTab[pHdr->NumberOfSymbols]; + char szShortName[16]; + if (g_cVerbose > 2) + for (uint32_t i = 0; i < pHdr->NumberOfSymbols; i++) + { + printf("sym[0x%02x]: sect=0x%04x value=0x%08x storageclass=0x%x name=%s\n", + i, paSymTab[i].SectionNumber, paSymTab[i].Value, paSymTab[i].StorageClass, + coffGetSymbolName(&paSymTab[i], pchStrTab, szShortName)); + i += paSymTab[i].NumberOfAuxSymbols; + } + /* Switch it to a x86 machine. */ pHdr->Machine = IMAGE_FILE_MACHINE_I386; @@ -349,5 +375,5 @@ */ bool fRet = true; - PCIMAGE_SECTION_HEADER paShdrs = (PCIMAGE_SECTION_HEADER)(pHdr + 1); + PIMAGE_SECTION_HEADER paShdrs = (PIMAGE_SECTION_HEADER)(pHdr + 1); for (uint32_t i = 0; i < pHdr->NumberOfSections; i++) { @@ -361,5 +387,5 @@ paShdrs[i].PointerToRelocations, paShdrs[i].NumberOfRelocations, paShdrs[i].PointerToLinenumbers, paShdrs[i].NumberOfLinenumbers, paShdrs[i].Characteristics); - uint32_t const cRelocs = paShdrs[i].NumberOfRelocations; + uint32_t cRelocs = paShdrs[i].NumberOfRelocations; if (cRelocs > 0) { @@ -380,4 +406,10 @@ bool const fIsPData = fInBinary && memcmp(paShdrs[i].Name, RT_STR_TUPLE(".pdata\0")) == 0; + bool const fIsText = fInBinary + && (paShdrs[i].Characteristics & (IMAGE_SCN_MEM_EXECUTE | IMAGE_SCN_CNT_CODE)); + + /* Whether we've seen any __ImageBase REL32 relocation that may later + be used with array access using the SIB encoding and ADDR32NB. */ + bool fSeenImageBase = false; /* @@ -425,7 +457,8 @@ while (off < 36) off += printf(" "); - printf(" %s\n", + printf(" %s %s\n", paRelocs[j].Type < RT_ELEMENTS(g_apszCoffAmd64RelTypes) - ? g_apszCoffAmd64RelTypes[paRelocs[j].Type] : "unknown"); + ? g_apszCoffAmd64RelTypes[paRelocs[j].Type] : "unknown", + coffGetSymbolName(&paSymTab[paRelocs[j].SymbolTableIndex], pchStrTab, szShortName)); } @@ -469,13 +502,69 @@ /* These are 1:1 conversions: */ case IMAGE_REL_AMD64_ADDR32: +#if 1 /* Turns out this is special when wlink is doing DOS/BIOS binaries. */ +/** @todo this still doesn't work for bs3-cmn-SelProtFar32ToFlat32.obj!! */ + paRelocs[j].Type = IMAGE_REL_I386_ABSOLUTE; /* Note! Don't believe MS pecoff.doc, this works with wlink. */ +#else paRelocs[j].Type = IMAGE_REL_I386_DIR32; uDir = IMAGE_REL_AMD64_ADDR32; +#endif break; case IMAGE_REL_AMD64_ADDR32NB: - paRelocs[j].Type = IMAGE_REL_I386_DIR32NB; - uDir = IMAGE_REL_AMD64_ADDR32NB; + if (fSeenImageBase && fIsText) /* This is voodoo. */ + paRelocs[j].Type = IMAGE_REL_I386_ABSOLUTE; /* Note! Don't believe MS pecoff.doc, this works with wlink. */ + else + { + paRelocs[j].Type = IMAGE_REL_I386_DIR32NB; + uDir = IMAGE_REL_AMD64_ADDR32NB; + } break; case IMAGE_REL_AMD64_REL32: paRelocs[j].Type = IMAGE_REL_I386_REL32; + + /* This is voodoo! */ + if ( fIsText + && strcmp(coffGetSymbolName(&paSymTab[paRelocs[j].SymbolTableIndex], pchStrTab, szShortName), + "__ImageBase") == 0) + { + if ( (uLoc.pu8[-1] & (X86_MODRM_MOD_MASK | X86_MODRM_RM_MASK)) == 5 /* disp32 + wrt */ + && uLoc.pu8[-2] == 0x8d /* LEA */ + && (uLoc.pu8[-3] & (0xf8 | X86_OP_REX_W)) == X86_OP_REX_W /* 64-bit reg */ ) + { + if (*uLoc.pu32) + { + error(pszFile, "__ImageBase fixup with disp %#x at rva=%#x in section #%u '%-8.8'!\n", + *uLoc.pu32, paRelocs[j].u.VirtualAddress, i, paShdrs[i].Name); + fRet = false; + } + + if (fSeenImageBase) + return error(pszFile, "More than one __ImageBase fixup! 2nd at rva=%#x in section #%u '%-8.8'\n", + paRelocs[j].u.VirtualAddress, i, paShdrs[i].Name); + if (g_cVerbose) + printf("Applying __ImageBase hack at rva=%#x in section #%u '%-8.8'\n", + paRelocs[j].u.VirtualAddress, i, paShdrs[i].Name); + + /* Convert it into a mov reg, dword 0. Leave the extra rex prefix, as it will be ignored. */ + uint8_t iReg = (uLoc.pu8[-1] >> X86_MODRM_REG_SHIFT) & X86_MODRM_REG_SMASK; + uLoc.pu8[-1] = 0xb8 | iReg; + uLoc.pu8[-2] = X86_OP_REX_R & uLoc.pu8[-3]; + fSeenImageBase = true; + + /* Neutralize the fixup. + Note! wlink takes the IMAGE_REL_I386_ABSOLUTE fixups seriously, so we cannot use that + to disable it, so instead we have to actually remove it from the fixup table. */ + cRelocs--; + if (j != cRelocs) + memmove(&paRelocs[j], &paRelocs[j + 1], (cRelocs - j) * sizeof(paRelocs[j])); + paShdrs[i].NumberOfRelocations = (uint16_t)cRelocs; + j--; + } + else + { + error(pszFile, "__ImageBase fixup that isn't a recognized LEA at rva=%#x in section #%u '%-8.8'!\n", + paRelocs[j].u.VirtualAddress, i, paShdrs[i].Name); + fRet = false; + } + } break; case IMAGE_REL_AMD64_SECTION: @@ -488,6 +577,10 @@ paRelocs[j].Type = IMAGE_REL_I386_SECREL7; break; - case IMAGE_REL_AMD64_ABSOLUTE: /* no-op for alignment. */ + case IMAGE_REL_AMD64_ABSOLUTE: paRelocs[j].Type = IMAGE_REL_I386_ABSOLUTE; + /* Turns out wlink takes this seriously, so it usage must be checked out. */ + error(pszFile, "ABSOLUTE fixup at rva=%#x in section #%u '%-8.8'\n", + paRelocs[j].u.VirtualAddress, i, paShdrs[i].Name); + fRet = false; break; Index: /trunk/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-first-common.mac =================================================================== --- /trunk/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-first-common.mac (revision 59899) +++ /trunk/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-first-common.mac (revision 59900) @@ -44,4 +44,6 @@ ; Entry point with eye-catcher. GLOBALNAME start +global __ImageBase ; for MS compiler +__ImageBase: jmp .after_eye_catcher db 10,13,'eye-catcher: BS3TEXT16',10,13