/* $Id: ldrELFRelocatable.cpp.h $ */ /** @file * IPRT - Binary Image Loader, Template for ELF Relocatable Images. */ /* * Copyright (C) 2006-2023 Oracle and/or its affiliates. * * This file is part of VirtualBox base platform packages, as * available from https://www.virtualbox.org. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation, in version 3 of the * License. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see . * * The contents of this file may alternatively be used under the terms * of the Common Development and Distribution License Version 1.0 * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included * in the VirtualBox distribution, in which case the provisions of the * CDDL are applicable instead of those of the GPL. * * You may elect to license modified versions of this file under the * terms and conditions of either the GPL or the CDDL or both. * * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0 */ /******************************************************************************* * Defined Constants And Macros * *******************************************************************************/ #if ELF_MODE == 32 # define RTLDRELF_NAME(name) rtldrELF32##name # define RTLDRELF_SUFF(name) name##32 # define RTLDRELF_MID(pre,suff) pre##32##suff # define FMT_ELF_ADDR "%08RX32" # define FMT_ELF_ADDR7 "%07RX32" # define FMT_ELF_HALF "%04RX16" # define FMT_ELF_OFF "%08RX32" # define FMT_ELF_SIZE "%08RX32" # define FMT_ELF_SWORD "%RI32" # define FMT_ELF_WORD "%08RX32" # define FMT_ELF_XWORD "%08RX32" # define FMT_ELF_SXWORD "%RI32" # define Elf_Xword Elf32_Word # define Elf_Sxword Elf32_Sword #elif ELF_MODE == 64 # define RTLDRELF_NAME(name) rtldrELF64##name # define RTLDRELF_SUFF(name) name##64 # define RTLDRELF_MID(pre,suff) pre##64##suff # define FMT_ELF_ADDR "%016RX64" # define FMT_ELF_ADDR7 "%08RX64" # define FMT_ELF_HALF "%04RX16" # define FMT_ELF_SHALF "%RI16" # define FMT_ELF_OFF "%016RX64" # define FMT_ELF_SIZE "%016RX64" # define FMT_ELF_SWORD "%RI32" # define FMT_ELF_WORD "%08RX32" # define FMT_ELF_XWORD "%016RX64" # define FMT_ELF_SXWORD "%RI64" # define Elf_Xword Elf64_Xword # define Elf_Sxword Elf64_Sxword #endif #define Elf_Ehdr RTLDRELF_MID(Elf,_Ehdr) #define Elf_Phdr RTLDRELF_MID(Elf,_Phdr) #define Elf_Shdr RTLDRELF_MID(Elf,_Shdr) #define Elf_Sym RTLDRELF_MID(Elf,_Sym) #define Elf_Rel RTLDRELF_MID(Elf,_Rel) #define Elf_Rela RTLDRELF_MID(Elf,_Rela) #define Elf_Nhdr RTLDRELF_MID(Elf,_Nhdr) #define Elf_Dyn RTLDRELF_MID(Elf,_Dyn) #define Elf_Addr RTLDRELF_MID(Elf,_Addr) #define Elf_Half RTLDRELF_MID(Elf,_Half) #define Elf_Off RTLDRELF_MID(Elf,_Off) #define Elf_Size RTLDRELF_MID(Elf,_Size) #define Elf_Sword RTLDRELF_MID(Elf,_Sword) #define Elf_Word RTLDRELF_MID(Elf,_Word) #define RTLDRMODELF RTLDRELF_MID(RTLDRMODELF,RT_NOTHING) #define PRTLDRMODELF RTLDRELF_MID(PRTLDRMODELF,RT_NOTHING) #define RTLDRMODELFSHX RTLDRELF_MID(RTLDRMODELFSHX,RT_NOTHING) #define PRTLDRMODELFSHX RTLDRELF_MID(PRTLDRMODELFSHX,RT_NOTHING) #define ELF_R_SYM(info) RTLDRELF_MID(ELF,_R_SYM)(info) #define ELF_R_TYPE(info) RTLDRELF_MID(ELF,_R_TYPE)(info) #define ELF_R_INFO(sym, type) RTLDRELF_MID(ELF,_R_INFO)(sym, type) #define ELF_ST_BIND(info) RTLDRELF_MID(ELF,_ST_BIND)(info) /******************************************************************************* * Structures and Typedefs * *******************************************************************************/ /** * Extra section info. */ typedef struct RTLDRMODELFSHX { /** The corresponding program header. */ uint16_t idxPhdr; /** The corresponding dynamic section entry (address). */ uint16_t idxDt; /** The DT tag. */ uint32_t uDtTag; } RTLDRMODELFSHX; typedef RTLDRMODELFSHX *PRTLDRMODELFSHX; /** * The ELF loader structure. */ typedef struct RTLDRMODELF { /** Core module structure. */ RTLDRMODINTERNAL Core; /** Pointer to readonly mapping of the image bits. * This mapping is provided by the pReader. */ const void *pvBits; /** The ELF header. */ Elf_Ehdr Ehdr; /** Pointer to our copy of the section headers with sh_addr as RVAs. * The virtual addresses in this array is the 0 based assignments we've given the image. * Not valid if the image is DONE. */ Elf_Shdr *paShdrs; /** Unmodified section headers (allocated after paShdrs, so no need to free). * Not valid if the image is DONE. */ Elf_Shdr const *paOrgShdrs; /** Runs parallel to paShdrs and is part of the same allocation. */ PRTLDRMODELFSHX paShdrExtras; /** Base section number, either 1 or zero depending on whether we've * re-used the NULL entry for .elf.headers in ET_EXEC/ET_DYN. */ unsigned iFirstSect; /** Set if the SHF_ALLOC section headers are in order of sh_addr. */ bool fShdrInOrder; /** The size of the loaded image. */ size_t cbImage; /** The image base address if it's an EXEC or DYN image. */ Elf_Addr LinkAddress; struct { /** The symbol section index. */ unsigned iSymSh; /** Number of symbols in the table. */ unsigned cSyms; /** Pointer to symbol table within RTLDRMODELF::pvBits. */ const Elf_Sym *paSyms; /** The string section index. */ unsigned iStrSh; /** Size of the string table. */ unsigned cbStr; /** Pointer to string table within RTLDRMODELF::pvBits. */ const char *pStr; } Rel /**< Regular symbols and strings. */ , Dyn /**< Dynamic symbols and strings. */; /** Pointer to section header string table within RTLDRMODELF::pvBits. */ const char *pShStr; /** Size of the section header string table. */ unsigned cbShStr; /** The '.eh_frame' section index. Zero if not searched for, ~0U if not found. */ unsigned iShEhFrame; /** The '.eh_frame_hdr' section index. Zero if not searched for, ~0U if not found. */ unsigned iShEhFrameHdr; /** The '.dynamic' / SHT_DYNAMIC section index. ~0U if not present. */ unsigned iShDynamic; /** Number of entries in paDynamic. */ unsigned cDynamic; /** The dynamic section (NULL for ET_REL). */ Elf_Dyn *paDynamic; /** Program headers (NULL for ET_REL). */ Elf_Phdr *paPhdrs; /** Info extracted from PT_DYNAMIC and the program headers. */ struct { /** DT_RELA/DT_REL. */ Elf_Addr uPtrRelocs; /** DT_RELASZ/DT_RELSZ. */ Elf_Xword cbRelocs; /** Non-zero if we've seen DT_RELAENT/DT_RELENT. */ unsigned cbRelocEntry; /** DT_RELA or DT_REL. */ unsigned uRelocType; /** The index of the section header matching DT_RELA/DT_REL. */ unsigned idxShRelocs; /** DT_JMPREL. */ Elf_Addr uPtrJmpRelocs; /** DT_PLTRELSZ. */ Elf_Xword cbJmpRelocs; /** DT_RELA or DT_REL (if we've seen DT_PLTREL). */ unsigned uJmpRelocType; /** The index of the section header matching DT_JMPREL. */ unsigned idxShJmpRelocs; } DynInfo; } RTLDRMODELF; /** Pointer to an ELF module instance. */ typedef RTLDRMODELF *PRTLDRMODELF; /** * Maps the image bits into memory and resolve pointers into it. * * @returns iprt status code. * @param pModElf The ELF loader module instance data. * @param fNeedsBits Set if we actually need the pvBits member. * If we don't, we can simply read the string and symbol sections, thus saving memory. */ static int RTLDRELF_NAME(MapBits)(PRTLDRMODELF pModElf, bool fNeedsBits) { NOREF(fNeedsBits); if (pModElf->pvBits) return VINF_SUCCESS; int rc = pModElf->Core.pReader->pfnMap(pModElf->Core.pReader, &pModElf->pvBits); if (RT_SUCCESS(rc)) { const uint8_t *pu8 = (const uint8_t *)pModElf->pvBits; if (pModElf->Rel.iSymSh != ~0U) pModElf->Rel.paSyms = (const Elf_Sym *)(pu8 + pModElf->paShdrs[pModElf->Rel.iSymSh].sh_offset); if (pModElf->Rel.iStrSh != ~0U) pModElf->Rel.pStr = (const char *)(pu8 + pModElf->paShdrs[pModElf->Rel.iStrSh].sh_offset); if (pModElf->Dyn.iSymSh != ~0U) pModElf->Dyn.paSyms = (const Elf_Sym *)(pu8 + pModElf->paShdrs[pModElf->Dyn.iSymSh].sh_offset); if (pModElf->Dyn.iStrSh != ~0U) pModElf->Dyn.pStr = (const char *)(pu8 + pModElf->paShdrs[pModElf->Dyn.iStrSh].sh_offset); pModElf->pShStr = (const char *)(pu8 + pModElf->paShdrs[pModElf->Ehdr.e_shstrndx].sh_offset); /* * Verify that the ends of the string tables have a zero terminator * (this avoids duplicating the appropriate checks later in the code accessing the string tables). * * sh_offset and sh_size were verfied in RTLDRELF_NAME(ValidateSectionHeader)() already so they * are safe to use. */ AssertMsgStmt( pModElf->Rel.iStrSh == ~0U || pModElf->Rel.pStr[pModElf->paShdrs[pModElf->Rel.iStrSh].sh_size - 1] == '\0', ("The string table is not zero terminated!\n"), rc = VERR_LDRELF_UNTERMINATED_STRING_TAB); AssertMsgStmt( pModElf->Dyn.iStrSh == ~0U || pModElf->Dyn.pStr[pModElf->paShdrs[pModElf->Dyn.iStrSh].sh_size - 1] == '\0', ("The string table is not zero terminated!\n"), rc = VERR_LDRELF_UNTERMINATED_STRING_TAB); AssertMsgStmt(pModElf->pShStr[pModElf->paShdrs[pModElf->Ehdr.e_shstrndx].sh_size - 1] == '\0', ("The section header string table is not zero terminated!\n"), rc = VERR_LDRELF_UNTERMINATED_STRING_TAB); if (RT_FAILURE(rc)) { /* Unmap. */ int rc2 = pModElf->Core.pReader->pfnUnmap(pModElf->Core.pReader, pModElf->pvBits); AssertRC(rc2); pModElf->pvBits = NULL; pModElf->Rel.paSyms = NULL; pModElf->Rel.pStr = NULL; pModElf->Dyn.paSyms = NULL; pModElf->Dyn.pStr = NULL; pModElf->pShStr = NULL; } } return rc; } /* * * EXEC & DYN. * EXEC & DYN. * EXEC & DYN. * EXEC & DYN. * EXEC & DYN. * */ /** * Get the symbol and symbol value. * * @returns iprt status code. * @param pModElf The ELF loader module instance data. * @param BaseAddr The base address which the module is being fixedup to. * @param pfnGetImport The callback function to use to resolve imports (aka unresolved externals). * @param pvUser User argument to pass to the callback. * @param iSym The symbol to get. * @param ppSym Where to store the symbol pointer on success. (read only) * @param pSymValue Where to store the symbol value on success. */ static int RTLDRELF_NAME(SymbolExecDyn)(PRTLDRMODELF pModElf, Elf_Addr BaseAddr, PFNRTLDRIMPORT pfnGetImport, void *pvUser, Elf_Size iSym, const Elf_Sym **ppSym, Elf_Addr *pSymValue) { /* * Validate and find the symbol. */ AssertMsgReturn(iSym < pModElf->Dyn.cSyms, ("iSym=%d is an invalid symbol index!\n", iSym), VERR_LDRELF_INVALID_SYMBOL_INDEX); const Elf_Sym *pSym = &pModElf->Dyn.paSyms[iSym]; *ppSym = pSym; AssertMsgReturn(pSym->st_name < pModElf->Dyn.cbStr, ("iSym=%d st_name=%d str sh_size=%d\n", iSym, pSym->st_name, pModElf->Dyn.cbStr), VERR_LDRELF_INVALID_SYMBOL_NAME_OFFSET); const char * const pszName = pModElf->Dyn.pStr + pSym->st_name; /* * Determine the symbol value. * * Symbols needs different treatment depending on which section their are in. * Undefined and absolute symbols goes into special non-existing sections. */ switch (pSym->st_shndx) { /* * Undefined symbol, needs resolving. * * Since ELF has no generic concept of importing from specific module (the OS/2 ELF format * has but that's an OS extension and only applies to programs and dlls), we'll have to ask * the resolver callback to do a global search. */ case SHN_UNDEF: { /* Try to resolve the symbol. */ RTUINTPTR Value; int rc = pfnGetImport(&pModElf->Core, "", pszName, ~0U, &Value, pvUser); AssertMsgRCReturn(rc, ("Failed to resolve '%s' (iSym=" FMT_ELF_SIZE " rc=%Rrc\n", pszName, iSym, rc), rc); *pSymValue = (Elf_Addr)Value; AssertMsgReturn((RTUINTPTR)*pSymValue == Value, ("Symbol value overflowed! '%s' (iSym=" FMT_ELF_SIZE "\n", pszName, iSym), VERR_SYMBOL_VALUE_TOO_BIG); Log2(("rtldrELF: #%-3d - UNDEF " FMT_ELF_ADDR " '%s'\n", iSym, *pSymValue, pszName)); break; } /* * Absolute symbols needs no fixing since they are, well, absolute. */ case SHN_ABS: *pSymValue = pSym->st_value; Log2(("rtldrELF: #%-3d - ABS " FMT_ELF_ADDR " '%s'\n", iSym, *pSymValue, pszName)); break; /* * All other symbols are addressed relative the image base in DYN and EXEC binaries. */ default: AssertMsgReturn(pSym->st_shndx < pModElf->Ehdr.e_shnum, ("iSym=%d st_shndx=%d e_shnum=%d pszName=%s\n", iSym, pSym->st_shndx, pModElf->Ehdr.e_shnum, pszName), VERR_BAD_EXE_FORMAT); *pSymValue = pSym->st_value + BaseAddr; Log2(("rtldrELF: #%-3d - %5d " FMT_ELF_ADDR " '%s'\n", iSym, pSym->st_shndx, *pSymValue, pszName)); break; } return VINF_SUCCESS; } #if ELF_MODE == 32 /** Helper for RelocateSectionExecDyn. */ DECLINLINE(const Elf_Shdr *) RTLDRELF_NAME(RvaToSectionHeader)(PRTLDRMODELF pModElf, Elf_Addr uRva) { const Elf_Shdr * const pShdrFirst = pModElf->paShdrs; const Elf_Shdr *pShdr = pShdrFirst + pModElf->Ehdr.e_shnum; while (--pShdr != pShdrFirst) if (uRva - pShdr->sh_addr /*rva*/ < pShdr->sh_size) return pShdr; AssertFailed(); return pShdr; } #endif /** * Applies the fixups for a section in an executable image. * * @returns iprt status code. * @param pModElf The ELF loader module instance data. * @param BaseAddr The base address which the module is being fixedup to. * @param pfnGetImport The callback function to use to resolve imports (aka unresolved externals). * @param pvUser User argument to pass to the callback. * @param SecAddr The section address. This is the address the relocations are relative to. * @param cbSec The section size. The relocations must be inside this. * @param pu8SecBaseR Where we read section bits from. * @param pu8SecBaseW Where we write section bits to. * @param pvRelocs Pointer to where we read the relocations from. * @param cbRelocs Size of the relocations. */ static int RTLDRELF_NAME(RelocateSectionExecDyn)(PRTLDRMODELF pModElf, Elf_Addr BaseAddr, PFNRTLDRIMPORT pfnGetImport, void *pvUser, const Elf_Addr SecAddr, Elf_Size cbSec, const uint8_t *pu8SecBaseR, uint8_t *pu8SecBaseW, const void *pvRelocs, Elf_Size cbRelocs) { #if ELF_MODE != 32 NOREF(pu8SecBaseR); #endif /* * Iterate the relocations. * The relocations are stored in an array of Elf32_Rel records and covers the entire relocation section. */ #if ELF_MODE == 32 const Elf_Shdr *pShdr = pModElf->paShdrs; const Elf_Addr offDelta = BaseAddr - pModElf->LinkAddress; #endif const Elf_Reloc *paRels = (const Elf_Reloc *)pvRelocs; const unsigned iRelMax = (unsigned)(cbRelocs / sizeof(paRels[0])); AssertMsgReturn(iRelMax == cbRelocs / sizeof(paRels[0]), (FMT_ELF_SIZE "\n", cbRelocs / sizeof(paRels[0])), VERR_IMAGE_TOO_BIG); for (unsigned iRel = 0; iRel < iRelMax; iRel++) { /* * Apply fixups not taking a symbol (will 'continue' rather than 'break'). */ AssertMsgReturn(paRels[iRel].r_offset < cbSec, (FMT_ELF_ADDR " " FMT_ELF_SIZE "\n", paRels[iRel].r_offset, cbSec), VERR_LDRELF_INVALID_RELOCATION_OFFSET); #if ELF_MODE == 32 if (paRels[iRel].r_offset - pShdr->sh_addr /*rva*/ >= pShdr->sh_size) pShdr = RTLDRELF_NAME(RvaToSectionHeader)(pModElf, paRels[iRel].r_offset); static const Elf_Addr s_uZero = 0; const Elf_Addr *pAddrR = RT_LIKELY(pShdr->sh_type != SHT_NOBITS) /* Where to read the addend. */ ? (const Elf_Addr *)(pu8SecBaseR + paRels[iRel].r_offset - pShdr->sh_addr /*rva*/ + pShdr->sh_offset) : &s_uZero; #endif Elf_Addr *pAddrW = (Elf_Addr *)(pu8SecBaseW + paRels[iRel].r_offset); /* Where to write the fixup. */ switch (ELF_R_TYPE(paRels[iRel].r_info)) { /* * Image relative (addend + base). */ #if ELF_MODE == 32 case R_386_RELATIVE: { const Elf_Addr Value = *pAddrR + BaseAddr; *(uint32_t *)pAddrW = Value; Log4((FMT_ELF_ADDR "/" FMT_ELF_ADDR7 ": R_386_RELATIVE Value=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, paRels[iRel].r_offset, Value)); AssertCompile(sizeof(Value) == sizeof(uint32_t)); continue; } #elif ELF_MODE == 64 case R_X86_64_RELATIVE: { const Elf_Addr Value = paRels[iRel].r_addend + BaseAddr; *(uint64_t *)pAddrW = (uint64_t)Value; Log4((FMT_ELF_ADDR "/" FMT_ELF_ADDR7 ": R_X86_64_RELATIVE Value=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, paRels[iRel].r_offset, Value)); AssertCompile(sizeof(Value) == sizeof(uint64_t)); continue; } #endif /* * R_XXX_NONE. */ #if ELF_MODE == 32 case R_386_NONE: #elif ELF_MODE == 64 case R_X86_64_NONE: #endif continue; } /* * Validate and find the symbol, resolve undefined ones. */ const Elf_Sym *pSym = NULL; /* shut up gcc */ Elf_Addr SymValue = 0; /* shut up gcc-4 */ int rc = RTLDRELF_NAME(SymbolExecDyn)(pModElf, BaseAddr, pfnGetImport, pvUser, ELF_R_SYM(paRels[iRel].r_info), &pSym, &SymValue); if (RT_FAILURE(rc)) return rc; /* * Apply the fixup. */ switch (ELF_R_TYPE(paRels[iRel].r_info)) { #if ELF_MODE == 32 /* * GOT/PLT. */ case R_386_GLOB_DAT: { *(uint32_t *)pAddrW = (uint32_t)SymValue; Log4((FMT_ELF_ADDR "/" FMT_ELF_ADDR7 ": R_386_GLOB_DAT Value=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, paRels[iRel].r_offset, SymValue)); AssertCompile(sizeof(SymValue) == sizeof(uint32_t)); break; } case R_386_JMP_SLOT: { *(uint32_t *)pAddrW = (uint32_t)SymValue; Log4((FMT_ELF_ADDR "/" FMT_ELF_ADDR7 ": R_386_JMP_SLOT Value=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, paRels[iRel].r_offset, SymValue)); AssertCompile(sizeof(SymValue) == sizeof(uint32_t)); break; } /* * Absolute addressing. */ case R_386_32: { Elf_Addr Value; if (pSym->st_shndx < pModElf->Ehdr.e_shnum) Value = *pAddrR + offDelta; /* Simplified. */ else if (pSym->st_shndx == SHN_ABS) continue; /* Internal fixup, no need to apply it. */ else if (pSym->st_shndx == SHN_UNDEF) Value = SymValue + *pAddrR; else AssertFailedReturn(VERR_LDR_GENERAL_FAILURE); /** @todo SHN_COMMON */ *(uint32_t *)pAddrW = Value; Log4((FMT_ELF_ADDR "/" FMT_ELF_ADDR7 ": R_386_32 Value=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, paRels[iRel].r_offset, Value)); break; } /* * PC relative addressing. */ case R_386_PC32: { Elf_Addr Value; if (pSym->st_shndx < pModElf->Ehdr.e_shnum) continue; /* Internal fixup, no need to apply it. */ else if (pSym->st_shndx == SHN_ABS) Value = *pAddrR + offDelta; /* Simplified. */ else if (pSym->st_shndx == SHN_UNDEF) { const Elf_Addr SourceAddr = SecAddr + paRels[iRel].r_offset + BaseAddr; /* Where the source really is. */ Value = SymValue + *(uint32_t *)pAddrR - SourceAddr; *(uint32_t *)pAddrW = Value; } else AssertFailedReturn(VERR_LDR_GENERAL_FAILURE); /** @todo SHN_COMMON */ Log4((FMT_ELF_ADDR "/" FMT_ELF_ADDR7 ": R_386_PC32 Value=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, paRels[iRel].r_offset, Value)); break; } #elif ELF_MODE == 64 /* * GOT/PLT. */ case R_X86_64_GLOB_DAT: { *(uint64_t *)pAddrW = (uint64_t)SymValue; Log4((FMT_ELF_ADDR "/" FMT_ELF_ADDR7 ": R_X86_64_GLOB_DAT Value=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, paRels[iRel].r_offset, SymValue)); AssertCompile(sizeof(SymValue) == sizeof(uint64_t)); break; } case R_X86_64_JMP_SLOT: { *(uint64_t *)pAddrW = (uint64_t)SymValue; Log4((FMT_ELF_ADDR "/" FMT_ELF_ADDR7 ": R_X86_64_JMP_SLOT Value=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, paRels[iRel].r_offset, SymValue)); AssertCompile(sizeof(SymValue) == sizeof(uint64_t)); break; } /* * Absolute addressing. */ case R_X86_64_64: { const Elf_Addr Value = SymValue + paRels[iRel].r_addend; *(uint64_t *)pAddrW = Value; Log4((FMT_ELF_ADDR "/" FMT_ELF_ADDR7 ": R_X86_64_64 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, paRels[iRel].r_offset, Value, SymValue)); break; } /* * Truncated 32-bit value (zero-extendedable to the 64-bit value). */ case R_X86_64_32: { const Elf_Addr Value = SymValue + paRels[iRel].r_addend; *(uint32_t *)pAddrW = (uint32_t)Value; Log4((FMT_ELF_ADDR "/" FMT_ELF_ADDR7 ": R_X86_64_32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, paRels[iRel].r_offset, Value, SymValue)); AssertMsgReturn((Elf_Addr)*(uint32_t *)pAddrW == SymValue, ("Value=" FMT_ELF_ADDR "\n", SymValue), VERR_SYMBOL_VALUE_TOO_BIG); break; } /* * Truncated 32-bit value (sign-extendedable to the 64-bit value). */ case R_X86_64_32S: { const Elf_Addr Value = SymValue + paRels[iRel].r_addend; *(int32_t *)pAddrW = (int32_t)Value; Log4((FMT_ELF_ADDR "/" FMT_ELF_ADDR7 ": R_X86_64_32S Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, paRels[iRel].r_offset, Value, SymValue)); AssertMsgReturn((Elf_Addr)*(int32_t *)pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); /** @todo check the sign-extending here. */ break; } /* * PC relative addressing. */ case R_X86_64_PC32: { const Elf_Addr SourceAddr = SecAddr + paRels[iRel].r_offset + BaseAddr; /* Where the source really is. */ const Elf_Addr Value = SymValue + paRels[iRel].r_addend - SourceAddr; *(int32_t *)pAddrW = (int32_t)Value; Log4((FMT_ELF_ADDR "/" FMT_ELF_ADDR7 ": R_X86_64_PC32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n", SourceAddr, paRels[iRel].r_offset, Value, SymValue)); AssertMsgReturn((Elf_Addr)*(int32_t *)pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); /** @todo check the sign-extending here. */ break; } #endif default: AssertMsgFailed(("Unknown relocation type: %d (iRel=%d iRelMax=%d)\n", ELF_R_TYPE(paRels[iRel].r_info), iRel, iRelMax)); return VERR_LDRELF_RELOCATION_NOT_SUPPORTED; } } return VINF_SUCCESS; } /* * * REL * REL * REL * REL * REL * */ /** * Get the symbol and symbol value. * * @returns iprt status code. * @param pModElf The ELF loader module instance data. * @param BaseAddr The base address which the module is being fixedup to. * @param pfnGetImport The callback function to use to resolve imports (aka unresolved externals). * @param pvUser User argument to pass to the callback. * @param iSym The symbol to get. * @param ppSym Where to store the symbol pointer on success. (read only) * @param pSymValue Where to store the symbol value on success. */ static int RTLDRELF_NAME(Symbol)(PRTLDRMODELF pModElf, Elf_Addr BaseAddr, PFNRTLDRIMPORT pfnGetImport, void *pvUser, Elf_Size iSym, const Elf_Sym **ppSym, Elf_Addr *pSymValue) { /* * Validate and find the symbol. */ AssertMsgReturn(iSym < pModElf->Rel.cSyms, ("iSym=%d is an invalid symbol index!\n", iSym), VERR_LDRELF_INVALID_SYMBOL_INDEX); const Elf_Sym *pSym = &pModElf->Rel.paSyms[iSym]; *ppSym = pSym; AssertMsgReturn(pSym->st_name < pModElf->Rel.cbStr, ("iSym=%d st_name=%d str sh_size=%d\n", iSym, pSym->st_name, pModElf->Rel.cbStr), VERR_LDRELF_INVALID_SYMBOL_NAME_OFFSET); const char *pszName = ELF_STR(pModElf, pSym->st_name); /* * Determine the symbol value. * * Symbols needs different treatment depending on which section their are in. * Undefined and absolute symbols goes into special non-existing sections. */ switch (pSym->st_shndx) { /* * Undefined symbol, needs resolving. * * Since ELF has no generic concept of importing from specific module (the OS/2 ELF format * has but that's an OS extension and only applies to programs and dlls), we'll have to ask * the resolver callback to do a global search. */ case SHN_UNDEF: { /* Try to resolve the symbol. */ RTUINTPTR Value; int rc = pfnGetImport(&pModElf->Core, "", pszName, ~0U, &Value, pvUser); AssertMsgRCReturn(rc, ("Failed to resolve '%s' (iSym=" FMT_ELF_SIZE " rc=%Rrc\n", pszName, iSym, rc), rc); *pSymValue = (Elf_Addr)Value; AssertMsgReturn((RTUINTPTR)*pSymValue == Value, ("Symbol value overflowed! '%s' (iSym=" FMT_ELF_SIZE ")\n", pszName, iSym), VERR_SYMBOL_VALUE_TOO_BIG); Log2(("rtldrELF: #%-3d - UNDEF " FMT_ELF_ADDR " '%s'\n", iSym, *pSymValue, pszName)); break; } /* * Absolute symbols needs no fixing since they are, well, absolute. */ case SHN_ABS: *pSymValue = pSym->st_value; Log2(("rtldrELF: #%-3d - ABS " FMT_ELF_ADDR " '%s'\n", iSym, *pSymValue, pszName)); break; /* * All other symbols are addressed relative to their section and need to be fixed up. */ default: if (pSym->st_shndx >= pModElf->Ehdr.e_shnum) { /* what about common symbols? */ AssertMsg(pSym->st_shndx < pModElf->Ehdr.e_shnum, ("iSym=%d st_shndx=%d e_shnum=%d pszName=%s\n", iSym, pSym->st_shndx, pModElf->Ehdr.e_shnum, pszName)); return VERR_BAD_EXE_FORMAT; } *pSymValue = pSym->st_value + pModElf->paShdrs[pSym->st_shndx].sh_addr + BaseAddr; Log2(("rtldrELF: #%-3d - %5d " FMT_ELF_ADDR " '%s'\n", iSym, pSym->st_shndx, *pSymValue, pszName)); break; } return VINF_SUCCESS; } /** * Applies the fixups for a sections. * * @returns iprt status code. * @param pModElf The ELF loader module instance data. * @param BaseAddr The base address which the module is being fixedup to. * @param pfnGetImport The callback function to use to resolve imports (aka unresolved externals). * @param pvUser User argument to pass to the callback. * @param SecAddr The section address. This is the address the relocations are relative to. * @param cbSec The section size. The relocations must be inside this. * @param pu8SecBaseR Where we read section bits from. * @param pu8SecBaseW Where we write section bits to. * @param pvRelocs Pointer to where we read the relocations from. * @param cbRelocs Size of the relocations. */ static int RTLDRELF_NAME(RelocateSectionRel)(PRTLDRMODELF pModElf, Elf_Addr BaseAddr, PFNRTLDRIMPORT pfnGetImport, void *pvUser, const Elf_Addr SecAddr, Elf_Size cbSec, const uint8_t *pu8SecBaseR, uint8_t *pu8SecBaseW, const void *pvRelocs, Elf_Size cbRelocs) { #if ELF_MODE != 32 NOREF(pu8SecBaseR); #endif /* * Iterate the relocations. * The relocations are stored in an array of Elf32_Rel records and covers the entire relocation section. */ const Elf_Reloc *paRels = (const Elf_Reloc *)pvRelocs; const unsigned iRelMax = (unsigned)(cbRelocs / sizeof(paRels[0])); AssertMsgReturn(iRelMax == cbRelocs / sizeof(paRels[0]), (FMT_ELF_SIZE "\n", cbRelocs / sizeof(paRels[0])), VERR_IMAGE_TOO_BIG); for (unsigned iRel = 0; iRel < iRelMax; iRel++) { /* * Skip R_XXX_NONE entries early to avoid confusion in the symbol * getter code. */ #if ELF_MODE == 32 if (ELF_R_TYPE(paRels[iRel].r_info) == R_386_NONE) continue; #elif ELF_MODE == 64 if (ELF_R_TYPE(paRels[iRel].r_info) == R_X86_64_NONE) continue; #endif /* * Get the symbol. */ const Elf_Sym *pSym = NULL; /* shut up gcc */ Elf_Addr SymValue = 0; /* shut up gcc-4 */ int rc = RTLDRELF_NAME(Symbol)(pModElf, BaseAddr, pfnGetImport, pvUser, ELF_R_SYM(paRels[iRel].r_info), &pSym, &SymValue); if (RT_FAILURE(rc)) return rc; Log3(("rtldrELF: " FMT_ELF_ADDR " %02x %06x - " FMT_ELF_ADDR " %3d %02x %s\n", paRels[iRel].r_offset, ELF_R_TYPE(paRels[iRel].r_info), (unsigned)ELF_R_SYM(paRels[iRel].r_info), SymValue, (unsigned)pSym->st_shndx, pSym->st_info, ELF_STR(pModElf, pSym->st_name))); /* * Apply the fixup. */ AssertMsgReturn(paRels[iRel].r_offset < cbSec, (FMT_ELF_ADDR " " FMT_ELF_SIZE "\n", paRels[iRel].r_offset, cbSec), VERR_LDRELF_INVALID_RELOCATION_OFFSET); #if ELF_MODE == 32 const Elf_Addr *pAddrR = (const Elf_Addr *)(pu8SecBaseR + paRels[iRel].r_offset); /* Where to read the addend. */ #endif Elf_Addr *pAddrW = (Elf_Addr *)(pu8SecBaseW + paRels[iRel].r_offset); /* Where to write the fixup. */ switch (ELF_R_TYPE(paRels[iRel].r_info)) { #if ELF_MODE == 32 /* * Absolute addressing. */ case R_386_32: { const Elf_Addr Value = SymValue + *pAddrR; *(uint32_t *)pAddrW = Value; Log4((FMT_ELF_ADDR": R_386_32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue)); break; } /* * PC relative addressing. */ case R_386_PC32: { const Elf_Addr SourceAddr = SecAddr + paRels[iRel].r_offset + BaseAddr; /* Where the source really is. */ const Elf_Addr Value = SymValue + *(uint32_t *)pAddrR - SourceAddr; *(uint32_t *)pAddrW = Value; Log4((FMT_ELF_ADDR": R_386_PC32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n", SourceAddr, Value, SymValue)); break; } /* ignore */ case R_386_NONE: break; #elif ELF_MODE == 64 /* * Absolute addressing */ case R_X86_64_64: { const Elf_Addr Value = SymValue + paRels[iRel].r_addend; *(uint64_t *)pAddrW = Value; Log4((FMT_ELF_ADDR": R_X86_64_64 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue)); break; } /* * Truncated 32-bit value (zero-extendedable to the 64-bit value). */ case R_X86_64_32: { const Elf_Addr Value = SymValue + paRels[iRel].r_addend; *(uint32_t *)pAddrW = (uint32_t)Value; Log4((FMT_ELF_ADDR": R_X86_64_32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue)); AssertMsgReturn((Elf_Addr)*(uint32_t *)pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); break; } /* * Truncated 32-bit value (sign-extendedable to the 64-bit value). */ case R_X86_64_32S: { const Elf_Addr Value = SymValue + paRels[iRel].r_addend; *(int32_t *)pAddrW = (int32_t)Value; Log4((FMT_ELF_ADDR": R_X86_64_32S Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n", SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue)); AssertMsgReturn((Elf_Addr)*(int32_t *)pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); /** @todo check the sign-extending here. */ break; } /* * PC relative addressing. */ case R_X86_64_PC32: case R_X86_64_PLT32: /* binutils commit 451875b4f976a527395e9303224c7881b65e12ed feature/regression. */ { const Elf_Addr SourceAddr = SecAddr + paRels[iRel].r_offset + BaseAddr; /* Where the source really is. */ const Elf_Addr Value = SymValue + paRels[iRel].r_addend - SourceAddr; *(int32_t *)pAddrW = (int32_t)Value; Log4((FMT_ELF_ADDR": R_X86_64_PC32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n", SourceAddr, Value, SymValue)); AssertMsgReturn((Elf_Addr)*(int32_t *)pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); /** @todo check the sign-extending here. */ break; } /* ignore */ case R_X86_64_NONE: break; #endif default: AssertMsgFailed(("Unknown relocation type: %d (iRel=%d iRelMax=%d)\n", ELF_R_TYPE(paRels[iRel].r_info), iRel, iRelMax)); return VERR_LDRELF_RELOCATION_NOT_SUPPORTED; } } return VINF_SUCCESS; } /** @copydoc RTLDROPS::pfnClose */ static DECLCALLBACK(int) RTLDRELF_NAME(Close)(PRTLDRMODINTERNAL pMod) { PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod; if (pModElf->paShdrs) { RTMemFree(pModElf->paShdrs); pModElf->paShdrs = NULL; } if (pModElf->paPhdrs) { RTMemFree(pModElf->paPhdrs); pModElf->paPhdrs = NULL; } if (pModElf->paDynamic) { RTMemFree(pModElf->paDynamic); pModElf->paDynamic = NULL; } if (pModElf->pvBits) { pModElf->Core.pReader->pfnUnmap(pModElf->Core.pReader, pModElf->pvBits); pModElf->pvBits = NULL; } return VINF_SUCCESS; } /** @copydoc RTLDROPS::Done */ static DECLCALLBACK(int) RTLDRELF_NAME(Done)(PRTLDRMODINTERNAL pMod) { NOREF(pMod); /*PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;*/ /** @todo Have to think more about this .... */ return -1; } /** @copydoc RTLDROPS::pfnEnumSymbols */ static DECLCALLBACK(int) RTLDRELF_NAME(EnumSymbols)(PRTLDRMODINTERNAL pMod, unsigned fFlags, const void *pvBits, RTUINTPTR BaseAddress, PFNRTLDRENUMSYMS pfnCallback, void *pvUser) { PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod; NOREF(pvBits); /* * Validate the input. */ Elf_Addr BaseAddr = (Elf_Addr)BaseAddress; AssertMsgReturn((RTUINTPTR)BaseAddr == BaseAddress, ("%RTptr", BaseAddress), VERR_IMAGE_BASE_TOO_HIGH); /* * Make sure we've got the string and symbol tables. (We don't need the pvBits.) */ int rc = RTLDRELF_NAME(MapBits)(pModElf, false); if (RT_FAILURE(rc)) return rc; /* * Enumerate the symbol table. */ const Elf_Sym *paSyms = pModElf->Rel.paSyms; unsigned cSyms = pModElf->Rel.cSyms; const char *pszzStr = pModElf->Rel.pStr; unsigned cbStr = pModElf->Rel.cbStr; if ( ( !(fFlags & RTLDR_ENUM_SYMBOL_FLAGS_ALL) && pModElf->Dyn.cSyms > 0) || cSyms == 0) { paSyms = pModElf->Dyn.paSyms; cSyms = pModElf->Dyn.cSyms; pszzStr = pModElf->Dyn.pStr; cbStr = pModElf->Dyn.cbStr; } for (unsigned iSym = 1; iSym < cSyms; iSym++) { /* * Skip imports (undefined). */ if (paSyms[iSym].st_shndx != SHN_UNDEF) { /* * Calc value and get name. */ Elf_Addr Value; if (paSyms[iSym].st_shndx == SHN_ABS) /* absolute symbols are not subject to any relocation. */ Value = paSyms[iSym].st_value; else if (paSyms[iSym].st_shndx < pModElf->Ehdr.e_shnum) { if (pModElf->Ehdr.e_type == ET_REL) /* relative to the section. */ Value = BaseAddr + paSyms[iSym].st_value + pModElf->paShdrs[paSyms[iSym].st_shndx].sh_addr; else /* Fixed up for link address. */ Value = BaseAddr + paSyms[iSym].st_value - pModElf->LinkAddress; } else { AssertMsgFailed(("Arg! paSyms[%u].st_shndx=" FMT_ELF_HALF "\n", iSym, paSyms[iSym].st_shndx)); return VERR_BAD_EXE_FORMAT; } AssertMsgReturn(paSyms[iSym].st_name < cbStr, ("String outside string table! iSym=%d paSyms[iSym].st_name=%#x\n", iSym, paSyms[iSym].st_name), VERR_LDRELF_INVALID_SYMBOL_NAME_OFFSET); const char * const pszName = pszzStr + paSyms[iSym].st_name; /* String termination was already checked when the string table was mapped. */ if ( *pszName != '\0' && ( (fFlags & RTLDR_ENUM_SYMBOL_FLAGS_ALL) || ELF_ST_BIND(paSyms[iSym].st_info) == STB_GLOBAL) ) { /* * Call back. */ AssertMsgReturn(Value == (RTUINTPTR)Value, (FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); rc = pfnCallback(pMod, pszName, iSym, (RTUINTPTR)Value, pvUser); if (rc) return rc; } } } return VINF_SUCCESS; } /** @copydoc RTLDROPS::GetImageSize */ static DECLCALLBACK(size_t) RTLDRELF_NAME(GetImageSize)(PRTLDRMODINTERNAL pMod) { PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod; return pModElf->cbImage; } /** @copydoc RTLDROPS::GetBits */ static DECLCALLBACK(int) RTLDRELF_NAME(GetBits)(PRTLDRMODINTERNAL pMod, void *pvBits, RTUINTPTR BaseAddress, PFNRTLDRIMPORT pfnGetImport, void *pvUser) { PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod; /* * This operation is currently only available on relocatable images. */ switch (pModElf->Ehdr.e_type) { case ET_REL: case ET_DYN: break; case ET_EXEC: Log(("RTLdrELF: %s: Executable images are not supported yet!\n", pModElf->Core.pReader->pfnLogName(pModElf->Core.pReader))); return VERR_LDRELF_EXEC; default: AssertFailedReturn(VERR_BAD_EXE_FORMAT); } /* * Load the bits into pvBits. */ const Elf_Shdr *paShdrs = pModElf->paShdrs; for (unsigned iShdr = 0; iShdr < pModElf->Ehdr.e_shnum; iShdr++) { if (paShdrs[iShdr].sh_flags & SHF_ALLOC) { AssertMsgReturn((size_t)paShdrs[iShdr].sh_size == (size_t)paShdrs[iShdr].sh_size, (FMT_ELF_SIZE "\n", paShdrs[iShdr].sh_size), VERR_IMAGE_TOO_BIG); switch (paShdrs[iShdr].sh_type) { case SHT_NOBITS: memset((uint8_t *)pvBits + paShdrs[iShdr].sh_addr, 0, (size_t)paShdrs[iShdr].sh_size); break; case SHT_PROGBITS: default: { int rc = pModElf->Core.pReader->pfnRead(pModElf->Core.pReader, (uint8_t *)pvBits + paShdrs[iShdr].sh_addr, (size_t)paShdrs[iShdr].sh_size, paShdrs[iShdr].sh_offset); if (RT_FAILURE(rc)) { Log(("RTLdrELF: %s: Read error when reading " FMT_ELF_SIZE " bytes at " FMT_ELF_OFF ", iShdr=%d\n", pModElf->Core.pReader->pfnLogName(pModElf->Core.pReader), paShdrs[iShdr].sh_size, paShdrs[iShdr].sh_offset, iShdr)); return rc; } } } } } /* * Relocate the image. */ return pModElf->Core.pOps->pfnRelocate(pMod, pvBits, BaseAddress, ~(RTUINTPTR)0, pfnGetImport, pvUser); } /** @copydoc RTLDROPS::Relocate */ static DECLCALLBACK(int) RTLDRELF_NAME(Relocate)(PRTLDRMODINTERNAL pMod, void *pvBits, RTUINTPTR NewBaseAddress, RTUINTPTR OldBaseAddress, PFNRTLDRIMPORT pfnGetImport, void *pvUser) { PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod; #ifdef LOG_ENABLED const char *pszLogName = pModElf->Core.pReader->pfnLogName(pModElf->Core.pReader); #endif NOREF(OldBaseAddress); /* * This operation is currently only available on relocatable images. */ switch (pModElf->Ehdr.e_type) { case ET_REL: case ET_DYN: break; case ET_EXEC: Log(("RTLdrELF: %s: Executable images are not supported yet!\n", pszLogName)); return VERR_LDRELF_EXEC; default: AssertFailedReturn(VERR_BAD_EXE_FORMAT); } /* * Validate the input. */ Elf_Addr BaseAddr = (Elf_Addr)NewBaseAddress; AssertMsgReturn((RTUINTPTR)BaseAddr == NewBaseAddress, ("%RTptr", NewBaseAddress), VERR_IMAGE_BASE_TOO_HIGH); /* * Map the image bits if not already done and setup pointer into it. */ int rc = RTLDRELF_NAME(MapBits)(pModElf, true); if (RT_FAILURE(rc)) return rc; /* * Iterate the sections looking for interesting SHT_REL[A] sections. * * In ET_REL files the SHT_REL[A] sections have the section index of * the section they contain fixups for in the sh_info member. */ const Elf_Shdr *paShdrs = pModElf->paShdrs; Log2(("rtLdrElf: %s: Fixing up image\n", pszLogName)); for (unsigned iShdr = 0; iShdr < pModElf->Ehdr.e_shnum; iShdr++) { const Elf_Shdr *pShdrRel = &paShdrs[iShdr]; /* * Skip sections without interest to us. */ #if ELF_MODE == 32 if (pShdrRel->sh_type != SHT_REL) #else if (pShdrRel->sh_type != SHT_RELA) #endif continue; if (pModElf->Ehdr.e_type == ET_REL) { if (pShdrRel->sh_info >= pModElf->Ehdr.e_shnum) continue; const Elf_Shdr *pShdr = &paShdrs[pShdrRel->sh_info]; /* the section to fixup. */ if (!(pShdr->sh_flags & SHF_ALLOC)) continue; /* * Relocate the section. */ Log2(("rtldrELF: %s: Relocation records for #%d [%s] (sh_info=%d sh_link=%d) found in #%d [%s] (sh_info=%d sh_link=%d)\n", pszLogName, (int)pShdrRel->sh_info, ELF_SH_STR(pModElf, pShdr->sh_name), (int)pShdr->sh_info, (int)pShdr->sh_link, iShdr, ELF_SH_STR(pModElf, pShdrRel->sh_name), (int)pShdrRel->sh_info, (int)pShdrRel->sh_link)); rc = RTLDRELF_NAME(RelocateSectionRel)(pModElf, BaseAddr, pfnGetImport, pvUser, pShdr->sh_addr, pShdr->sh_size, (const uint8_t *)pModElf->pvBits + pShdr->sh_offset, (uint8_t *)pvBits + pShdr->sh_addr, (const uint8_t *)pModElf->pvBits + pShdrRel->sh_offset, pShdrRel->sh_size); } else rc = RTLDRELF_NAME(RelocateSectionExecDyn)(pModElf, BaseAddr, pfnGetImport, pvUser, 0, (Elf_Size)pModElf->cbImage, (const uint8_t *)pModElf->pvBits /** @todo file offset ?? */, (uint8_t *)pvBits, (const uint8_t *)pModElf->pvBits + pShdrRel->sh_offset, pShdrRel->sh_size); if (RT_FAILURE(rc)) return rc; } return VINF_SUCCESS; } /** * Worker for pfnGetSymbolEx. */ static int RTLDRELF_NAME(ReturnSymbol)(PRTLDRMODELF pThis, const Elf_Sym *pSym, Elf_Addr uBaseAddr, PRTUINTPTR pValue) { Elf_Addr Value; if (pSym->st_shndx == SHN_ABS) /* absolute symbols are not subject to any relocation. */ Value = pSym->st_value; else if (pSym->st_shndx < pThis->Ehdr.e_shnum) { if (pThis->Ehdr.e_type == ET_REL) /* relative to the section. */ Value = uBaseAddr + pSym->st_value + pThis->paShdrs[pSym->st_shndx].sh_addr; else /* Fixed up for link address. */ Value = uBaseAddr + pSym->st_value - pThis->LinkAddress; } else { AssertMsgFailed(("Arg! pSym->st_shndx=%d\n", pSym->st_shndx)); return VERR_BAD_EXE_FORMAT; } AssertMsgReturn(Value == (RTUINTPTR)Value, (FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); *pValue = (RTUINTPTR)Value; return VINF_SUCCESS; } /** @copydoc RTLDROPS::pfnGetSymbolEx */ static DECLCALLBACK(int) RTLDRELF_NAME(GetSymbolEx)(PRTLDRMODINTERNAL pMod, const void *pvBits, RTUINTPTR BaseAddress, uint32_t iOrdinal, const char *pszSymbol, RTUINTPTR *pValue) { PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod; NOREF(pvBits); /* * Validate the input. */ Elf_Addr uBaseAddr = (Elf_Addr)BaseAddress; AssertMsgReturn((RTUINTPTR)uBaseAddr == BaseAddress, ("%RTptr", BaseAddress), VERR_IMAGE_BASE_TOO_HIGH); /* * Map the image bits if not already done and setup pointer into it. */ int rc = RTLDRELF_NAME(MapBits)(pModElf, true); if (RT_FAILURE(rc)) return rc; /* * Calc all kinds of pointers before we start iterating the symbol table. */ const Elf_Sym *paSyms = pModElf->Rel.paSyms; unsigned cSyms = pModElf->Rel.cSyms; const char *pszzStr = pModElf->Rel.pStr; unsigned cbStr = pModElf->Rel.cbStr; if (pModElf->Dyn.cSyms > 0) { paSyms = pModElf->Dyn.paSyms; cSyms = pModElf->Dyn.cSyms; pszzStr = pModElf->Dyn.pStr; cbStr = pModElf->Dyn.cbStr; } if (iOrdinal == UINT32_MAX) { for (unsigned iSym = 1; iSym < cSyms; iSym++) { /* Undefined symbols are not exports, they are imports. */ if ( paSyms[iSym].st_shndx != SHN_UNDEF && ( ELF_ST_BIND(paSyms[iSym].st_info) == STB_GLOBAL || ELF_ST_BIND(paSyms[iSym].st_info) == STB_WEAK)) { /* Validate the name string and try match with it. */ AssertMsgReturn(paSyms[iSym].st_name < cbStr, ("String outside string table! iSym=%d paSyms[iSym].st_name=%#x\n", iSym, paSyms[iSym].st_name), VERR_LDRELF_INVALID_SYMBOL_NAME_OFFSET); if (!strcmp(pszSymbol, pszzStr + paSyms[iSym].st_name)) { /* matched! */ return RTLDRELF_NAME(ReturnSymbol)(pModElf, &paSyms[iSym], uBaseAddr, pValue); } } } } else if (iOrdinal < cSyms) { if ( paSyms[iOrdinal].st_shndx != SHN_UNDEF && ( ELF_ST_BIND(paSyms[iOrdinal].st_info) == STB_GLOBAL || ELF_ST_BIND(paSyms[iOrdinal].st_info) == STB_WEAK)) return RTLDRELF_NAME(ReturnSymbol)(pModElf, &paSyms[iOrdinal], uBaseAddr, pValue); } return VERR_SYMBOL_NOT_FOUND; } /** @copydoc RTLDROPS::pfnEnumDbgInfo */ static DECLCALLBACK(int) RTLDRELF_NAME(EnumDbgInfo)(PRTLDRMODINTERNAL pMod, const void *pvBits, PFNRTLDRENUMDBG pfnCallback, void *pvUser) { PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod; RT_NOREF_PV(pvBits); /* * Map the image bits if not already done and setup pointer into it. */ int rc = RTLDRELF_NAME(MapBits)(pModElf, true); if (RT_FAILURE(rc)) return rc; /* * Do the enumeration. */ const Elf_Shdr *paShdrs = pModElf->paOrgShdrs; for (unsigned iShdr = 0; iShdr < pModElf->Ehdr.e_shnum; iShdr++) { /* Debug sections are expected to be PROGBITS and not allocated. */ if (paShdrs[iShdr].sh_type != SHT_PROGBITS) continue; if (paShdrs[iShdr].sh_flags & SHF_ALLOC) continue; RTLDRDBGINFO DbgInfo; const char *pszSectName = ELF_SH_STR(pModElf, paShdrs[iShdr].sh_name); if ( !strncmp(pszSectName, RT_STR_TUPLE(".debug_")) || !strcmp(pszSectName, ".WATCOM_references") ) { RT_ZERO(DbgInfo.u); DbgInfo.enmType = RTLDRDBGINFOTYPE_DWARF; DbgInfo.pszExtFile = NULL; DbgInfo.offFile = paShdrs[iShdr].sh_offset; DbgInfo.cb = paShdrs[iShdr].sh_size; DbgInfo.u.Dwarf.pszSection = pszSectName; } else if (!strcmp(pszSectName, ".gnu_debuglink")) { if ((paShdrs[iShdr].sh_size & 3) || paShdrs[iShdr].sh_size < 8) return VERR_BAD_EXE_FORMAT; RT_ZERO(DbgInfo.u); DbgInfo.enmType = RTLDRDBGINFOTYPE_DWARF_DWO; DbgInfo.pszExtFile = (const char *)((uintptr_t)pModElf->pvBits + (uintptr_t)paShdrs[iShdr].sh_offset); if (!RTStrEnd(DbgInfo.pszExtFile, paShdrs[iShdr].sh_size)) return VERR_BAD_EXE_FORMAT; DbgInfo.u.Dwo.uCrc32 = *(uint32_t *)((uintptr_t)DbgInfo.pszExtFile + (uintptr_t)paShdrs[iShdr].sh_size - sizeof(uint32_t)); DbgInfo.offFile = -1; DbgInfo.cb = 0; } else continue; DbgInfo.LinkAddress = NIL_RTLDRADDR; DbgInfo.iDbgInfo = iShdr - 1; rc = pfnCallback(pMod, &DbgInfo, pvUser); if (rc != VINF_SUCCESS) return rc; } return VINF_SUCCESS; } /** * Locate the next allocated section by RVA (sh_addr). * * This is a helper for EnumSegments and SegOffsetToRva. * * @returns Pointer to the section header if found, NULL if none. * @param pModElf The module instance. * @param iShdrCur The current section header. */ static const Elf_Shdr *RTLDRELF_NAME(GetNextAllocatedSection)(PRTLDRMODELF pModElf, unsigned iShdrCur) { unsigned const cShdrs = pModElf->Ehdr.e_shnum; const Elf_Shdr * const paShdrs = pModElf->paShdrs; if (pModElf->fShdrInOrder) { for (unsigned iShdr = iShdrCur + 1; iShdr < cShdrs; iShdr++) if (paShdrs[iShdr].sh_flags & SHF_ALLOC) return &paShdrs[iShdr]; } else { Elf_Addr const uEndCur = paShdrs[iShdrCur].sh_addr + paShdrs[iShdrCur].sh_size; Elf_Addr offBest = ~(Elf_Addr)0; unsigned iBest = cShdrs; for (unsigned iShdr = pModElf->iFirstSect; iShdr < cShdrs; iShdr++) if ((paShdrs[iShdr].sh_flags & SHF_ALLOC) && iShdr != iShdrCur) { Elf_Addr const offDelta = paShdrs[iShdr].sh_addr - uEndCur; if ( offDelta < offBest && paShdrs[iShdr].sh_addr >= uEndCur) { offBest = offDelta; iBest = iShdr; } } if (iBest < cShdrs) return &paShdrs[iBest]; } return NULL; } /** @copydoc RTLDROPS::pfnEnumSegments. */ static DECLCALLBACK(int) RTLDRELF_NAME(EnumSegments)(PRTLDRMODINTERNAL pMod, PFNRTLDRENUMSEGS pfnCallback, void *pvUser) { PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod; /* * Map the image bits if not already done and setup pointer into it. */ int rc = RTLDRELF_NAME(MapBits)(pModElf, true); if (RT_FAILURE(rc)) return rc; /* * Do the enumeration. */ char szName[32]; Elf_Addr uPrevMappedRva = 0; const Elf_Shdr *paShdrs = pModElf->paShdrs; const Elf_Shdr *paOrgShdrs = pModElf->paOrgShdrs; for (unsigned iShdr = pModElf->iFirstSect; iShdr < pModElf->Ehdr.e_shnum; iShdr++) { RTLDRSEG Seg; if (iShdr != 0) { Seg.pszName = ELF_SH_STR(pModElf, paShdrs[iShdr].sh_name); Seg.cchName = (uint32_t)strlen(Seg.pszName); if (Seg.cchName == 0) { Seg.pszName = szName; Seg.cchName = (uint32_t)RTStrPrintf(szName, sizeof(szName), "UnamedSect%02u", iShdr); } } else { Seg.pszName = ".elf.headers"; Seg.cchName = 12; } Seg.SelFlat = 0; Seg.Sel16bit = 0; Seg.fFlags = 0; Seg.fProt = RTMEM_PROT_READ; if (paShdrs[iShdr].sh_flags & SHF_WRITE) Seg.fProt |= RTMEM_PROT_WRITE; if (paShdrs[iShdr].sh_flags & SHF_EXECINSTR) Seg.fProt |= RTMEM_PROT_EXEC; Seg.cb = paShdrs[iShdr].sh_size; Seg.Alignment = paShdrs[iShdr].sh_addralign; if (paShdrs[iShdr].sh_flags & SHF_ALLOC) { Seg.LinkAddress = paOrgShdrs[iShdr].sh_addr; Seg.RVA = paShdrs[iShdr].sh_addr; const Elf_Shdr *pShdr2 = RTLDRELF_NAME(GetNextAllocatedSection)(pModElf, iShdr); if (pShdr2) Seg.cbMapped = pShdr2->sh_addr - paShdrs[iShdr].sh_addr; else Seg.cbMapped = pModElf->cbImage - paShdrs[iShdr].sh_addr; uPrevMappedRva = Seg.RVA; } else { Seg.LinkAddress = NIL_RTLDRADDR; Seg.RVA = NIL_RTLDRADDR; Seg.cbMapped = NIL_RTLDRADDR; } if (paShdrs[iShdr].sh_type != SHT_NOBITS) { Seg.offFile = paShdrs[iShdr].sh_offset; Seg.cbFile = paShdrs[iShdr].sh_size; } else { Seg.offFile = -1; Seg.cbFile = 0; } rc = pfnCallback(pMod, &Seg, pvUser); if (rc != VINF_SUCCESS) return rc; } return VINF_SUCCESS; } /** @copydoc RTLDROPS::pfnLinkAddressToSegOffset. */ static DECLCALLBACK(int) RTLDRELF_NAME(LinkAddressToSegOffset)(PRTLDRMODINTERNAL pMod, RTLDRADDR LinkAddress, uint32_t *piSeg, PRTLDRADDR poffSeg) { PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod; const Elf_Shdr *pShdrEnd = NULL; unsigned cLeft = pModElf->Ehdr.e_shnum - pModElf->iFirstSect; const Elf_Shdr *pShdr = &pModElf->paOrgShdrs[pModElf->Ehdr.e_shnum]; while (cLeft-- > 0) { pShdr--; if (pShdr->sh_flags & SHF_ALLOC) { RTLDRADDR offSeg = LinkAddress - pShdr->sh_addr; if (offSeg < pShdr->sh_size) { *poffSeg = offSeg; *piSeg = cLeft; return VINF_SUCCESS; } if (offSeg == pShdr->sh_size) pShdrEnd = pShdr; } } if (pShdrEnd) { *poffSeg = pShdrEnd->sh_size; *piSeg = pShdrEnd - pModElf->paOrgShdrs - pModElf->iFirstSect; return VINF_SUCCESS; } return VERR_LDR_INVALID_LINK_ADDRESS; } /** @copydoc RTLDROPS::pfnLinkAddressToRva. */ static DECLCALLBACK(int) RTLDRELF_NAME(LinkAddressToRva)(PRTLDRMODINTERNAL pMod, RTLDRADDR LinkAddress, PRTLDRADDR pRva) { PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod; uint32_t iSeg; RTLDRADDR offSeg; int rc = RTLDRELF_NAME(LinkAddressToSegOffset)(pMod, LinkAddress, &iSeg, &offSeg); if (RT_SUCCESS(rc)) *pRva = pModElf->paShdrs[iSeg + pModElf->iFirstSect].sh_addr + offSeg; return rc; } /** @copydoc RTLDROPS::pfnSegOffsetToRva. */ static DECLCALLBACK(int) RTLDRELF_NAME(SegOffsetToRva)(PRTLDRMODINTERNAL pMod, uint32_t iSeg, RTLDRADDR offSeg, PRTLDRADDR pRva) { PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod; if (iSeg >= pModElf->Ehdr.e_shnum - pModElf->iFirstSect) return VERR_LDR_INVALID_SEG_OFFSET; iSeg += pModElf->iFirstSect; /* skip section 0 if not used */ if (offSeg > pModElf->paShdrs[iSeg].sh_size) { const Elf_Shdr *pShdr2 = RTLDRELF_NAME(GetNextAllocatedSection)(pModElf, iSeg); if ( !pShdr2 || offSeg > (pShdr2->sh_addr - pModElf->paShdrs[iSeg].sh_addr)) return VERR_LDR_INVALID_SEG_OFFSET; } if (!(pModElf->paShdrs[iSeg].sh_flags & SHF_ALLOC)) return VERR_LDR_INVALID_SEG_OFFSET; *pRva = pModElf->paShdrs[iSeg].sh_addr; return VINF_SUCCESS; } /** @copydoc RTLDROPS::pfnRvaToSegOffset. */ static DECLCALLBACK(int) RTLDRELF_NAME(RvaToSegOffset)(PRTLDRMODINTERNAL pMod, RTLDRADDR Rva, uint32_t *piSeg, PRTLDRADDR poffSeg) { PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod; Elf_Addr PrevAddr = 0; unsigned cLeft = pModElf->Ehdr.e_shnum - pModElf->iFirstSect; const Elf_Shdr *pShdr = &pModElf->paShdrs[pModElf->Ehdr.e_shnum]; while (cLeft-- > 0) { pShdr--; if (pShdr->sh_flags & SHF_ALLOC) { Elf_Addr cbSeg = PrevAddr ? PrevAddr - pShdr->sh_addr : pShdr->sh_size; RTLDRADDR offSeg = Rva - pShdr->sh_addr; if (offSeg <= cbSeg) { *poffSeg = offSeg; *piSeg = cLeft; return VINF_SUCCESS; } PrevAddr = pShdr->sh_addr; } } return VERR_LDR_INVALID_RVA; } /** @callback_method_impl{FNRTLDRIMPORT, Stub used by ReadDbgInfo.} */ static DECLCALLBACK(int) RTLDRELF_NAME(GetImportStubCallback)(RTLDRMOD hLdrMod, const char *pszModule, const char *pszSymbol, unsigned uSymbol, PRTLDRADDR pValue, void *pvUser) { RT_NOREF_PV(hLdrMod); RT_NOREF_PV(pszModule); RT_NOREF_PV(pszSymbol); RT_NOREF_PV(uSymbol); RT_NOREF_PV(pValue); RT_NOREF_PV(pvUser); return VERR_SYMBOL_NOT_FOUND; } /** @copydoc RTLDROPS::pfnReadDbgInfo. */ static DECLCALLBACK(int) RTLDRELF_NAME(ReadDbgInfo)(PRTLDRMODINTERNAL pMod, uint32_t iDbgInfo, RTFOFF off, size_t cb, void *pvBuf) { PRTLDRMODELF pThis = (PRTLDRMODELF)pMod; LogFlow(("%s: iDbgInfo=%#x off=%RTfoff cb=%#zu\n", __FUNCTION__, iDbgInfo, off, cb)); /* * Input validation. */ AssertReturn(iDbgInfo < pThis->Ehdr.e_shnum && iDbgInfo + 1 < pThis->Ehdr.e_shnum, VERR_INVALID_PARAMETER); iDbgInfo++; AssertReturn(!(pThis->paShdrs[iDbgInfo].sh_flags & SHF_ALLOC), VERR_INVALID_PARAMETER); AssertReturn(pThis->paShdrs[iDbgInfo].sh_type == SHT_PROGBITS, VERR_INVALID_PARAMETER); AssertReturn(pThis->paShdrs[iDbgInfo].sh_offset == (uint64_t)off, VERR_INVALID_PARAMETER); AssertReturn(pThis->paShdrs[iDbgInfo].sh_size == cb, VERR_INVALID_PARAMETER); uint64_t cbRawImage = pThis->Core.pReader->pfnSize(pThis->Core.pReader); AssertReturn(off >= 0 && cb <= cbRawImage && (uint64_t)off + cb <= cbRawImage, VERR_INVALID_PARAMETER); /* * Read it from the file and look for fixup sections. */ int rc; if (pThis->pvBits) memcpy(pvBuf, (const uint8_t *)pThis->pvBits + (size_t)off, cb); else { rc = pThis->Core.pReader->pfnRead(pThis->Core.pReader, pvBuf, cb, off); if (RT_FAILURE(rc)) return rc; } uint32_t iRelocs = iDbgInfo + 1; if ( iRelocs >= pThis->Ehdr.e_shnum || pThis->paShdrs[iRelocs].sh_info != iDbgInfo || ( pThis->paShdrs[iRelocs].sh_type != SHT_REL && pThis->paShdrs[iRelocs].sh_type != SHT_RELA) ) { iRelocs = 0; while ( iRelocs < pThis->Ehdr.e_shnum && ( pThis->paShdrs[iRelocs].sh_info != iDbgInfo || ( pThis->paShdrs[iRelocs].sh_type != SHT_REL && pThis->paShdrs[iRelocs].sh_type != SHT_RELA)) ) iRelocs++; } if ( iRelocs < pThis->Ehdr.e_shnum && pThis->paShdrs[iRelocs].sh_size > 0) { /* * Load the relocations. */ uint8_t *pbRelocsBuf = NULL; const uint8_t *pbRelocs; if (pThis->pvBits) pbRelocs = (const uint8_t *)pThis->pvBits + pThis->paShdrs[iRelocs].sh_offset; else { pbRelocs = pbRelocsBuf = (uint8_t *)RTMemTmpAlloc(pThis->paShdrs[iRelocs].sh_size); if (!pbRelocsBuf) return VERR_NO_TMP_MEMORY; rc = pThis->Core.pReader->pfnRead(pThis->Core.pReader, pbRelocsBuf, pThis->paShdrs[iRelocs].sh_size, pThis->paShdrs[iRelocs].sh_offset); if (RT_FAILURE(rc)) { RTMemTmpFree(pbRelocsBuf); return rc; } } /* * Apply the relocations. */ if (pThis->Ehdr.e_type == ET_REL) rc = RTLDRELF_NAME(RelocateSectionRel)(pThis, pThis->LinkAddress, RTLDRELF_NAME(GetImportStubCallback), NULL /*pvUser*/, pThis->paShdrs[iDbgInfo].sh_addr, pThis->paShdrs[iDbgInfo].sh_size, (const uint8_t *)pvBuf, (uint8_t *)pvBuf, pbRelocs, pThis->paShdrs[iRelocs].sh_size); else rc = RTLDRELF_NAME(RelocateSectionExecDyn)(pThis, pThis->LinkAddress, RTLDRELF_NAME(GetImportStubCallback), NULL /*pvUser*/, pThis->paShdrs[iDbgInfo].sh_addr, pThis->paShdrs[iDbgInfo].sh_size, (const uint8_t *)pvBuf, (uint8_t *)pvBuf, pbRelocs, pThis->paShdrs[iRelocs].sh_size); RTMemTmpFree(pbRelocsBuf); } else rc = VINF_SUCCESS; return rc; } /** * Handles RTLDRPROP_BUILDID queries. */ static int RTLDRELF_NAME(QueryPropBuildId)(PRTLDRMODELF pThis, void *pvBuf, size_t cbBuf, size_t *pcbRet) { /* * Map the image bits if not already done and setup pointer into it. */ int rc = RTLDRELF_NAME(MapBits)(pThis, true); if (RT_FAILURE(rc)) return rc; /* * Search for the build ID. */ const Elf_Shdr *paShdrs = pThis->paOrgShdrs; for (unsigned iShdr = 0; iShdr < pThis->Ehdr.e_shnum; iShdr++) { const char *pszSectName = ELF_SH_STR(pThis, paShdrs[iShdr].sh_name); if (!strcmp(pszSectName, ".note.gnu.build-id")) { if ((paShdrs[iShdr].sh_size & 3) || paShdrs[iShdr].sh_size < sizeof(Elf_Nhdr)) return VERR_BAD_EXE_FORMAT; Elf_Nhdr *pNHdr = (Elf_Nhdr *)((uintptr_t)pThis->pvBits + (uintptr_t)paShdrs[iShdr].sh_offset); if ( pNHdr->n_namesz > paShdrs[iShdr].sh_size || pNHdr->n_descsz > paShdrs[iShdr].sh_size || (paShdrs[iShdr].sh_size - pNHdr->n_descsz) < pNHdr->n_namesz || pNHdr->n_type != NT_GNU_BUILD_ID) return VERR_BAD_EXE_FORMAT; const char *pszOwner = (const char *)(pNHdr + 1); if ( !RTStrEnd(pszOwner, pNHdr->n_namesz) || strcmp(pszOwner, "GNU")) return VERR_BAD_EXE_FORMAT; if (cbBuf < pNHdr->n_descsz) return VERR_BUFFER_OVERFLOW; memcpy(pvBuf, pszOwner + pNHdr->n_namesz, pNHdr->n_descsz); *pcbRet = pNHdr->n_descsz; return VINF_SUCCESS; } } return VERR_NOT_FOUND; } /** @interface_method_impl{RTLDROPS,pfnQueryProp} */ static DECLCALLBACK(int) RTLDRELF_NAME(QueryProp)(PRTLDRMODINTERNAL pMod, RTLDRPROP enmProp, void const *pvBits, void *pvBuf, size_t cbBuf, size_t *pcbRet) { PRTLDRMODELF pThis = (PRTLDRMODELF)pMod; RT_NOREF(pvBits); switch (enmProp) { case RTLDRPROP_BUILDID: return RTLDRELF_NAME(QueryPropBuildId)(pThis, pvBuf, cbBuf, pcbRet); case RTLDRPROP_IS_SIGNED: *pcbRet = sizeof(bool); return rtLdrELFLnxKModQueryPropIsSigned(pThis->Core.pReader, (bool *)pvBuf); case RTLDRPROP_PKCS7_SIGNED_DATA: *pcbRet = sizeof(bool); return rtLdrELFLnxKModQueryPropPkcs7SignedData(pThis->Core.pReader, pvBuf, cbBuf, pcbRet); default: return VERR_NOT_FOUND; } } /** * @interface_method_impl{RTLDROPS,pfnUnwindFrame} */ static DECLCALLBACK(int) RTLDRELF_NAME(UnwindFrame)(PRTLDRMODINTERNAL pMod, void const *pvBits, uint32_t iSeg, RTUINTPTR off, PRTDBGUNWINDSTATE pState) { PRTLDRMODELF pThis = (PRTLDRMODELF)pMod; LogFlow(("%s: iSeg=%#x off=%RTptr\n", __FUNCTION__, iSeg, off)); /* * Process the input address, making us both RVA and proper seg:offset out of it. */ int rc; RTLDRADDR uRva = off; if (iSeg == UINT32_MAX) rc = RTLDRELF_NAME(RvaToSegOffset)(pMod, uRva, &iSeg, &off); else rc = RTLDRELF_NAME(SegOffsetToRva)(pMod, iSeg, off, &uRva); AssertRCReturn(rc, rc); /* * Map the image bits if not already done and setup pointer into it. */ RT_NOREF(pvBits); /** @todo Try use passed in pvBits? */ rc = RTLDRELF_NAME(MapBits)(pThis, true); if (RT_FAILURE(rc)) return rc; /* * Do we need to search for .eh_frame and .eh_frame_hdr? */ if (pThis->iShEhFrame == 0) { pThis->iShEhFrame = ~0U; pThis->iShEhFrameHdr = ~0U; unsigned cLeft = 2; for (unsigned iShdr = 1; iShdr < pThis->Ehdr.e_shnum; iShdr++) { const char *pszName = ELF_SH_STR(pThis, pThis->paShdrs[iShdr].sh_name); if ( pszName[0] == '.' && pszName[1] == 'e' && pszName[2] == 'h' && pszName[3] == '_' && pszName[4] == 'f' && pszName[5] == 'r' && pszName[6] == 'a' && pszName[7] == 'm' && pszName[8] == 'e') { if (pszName[9] == '\0') pThis->iShEhFrame = iShdr; else if ( pszName[9] == '_' && pszName[10] == 'h' && pszName[11] == 'd' && pszName[12] == 'r' && pszName[13] == '\0') pThis->iShEhFrameHdr = iShdr; else continue; if (--cLeft == 0) break; } } } /* * Any info present? */ unsigned iShdr = pThis->iShEhFrame; if ( iShdr != ~0U && pThis->paShdrs[iShdr].sh_size > 0) { if (pThis->paShdrs[iShdr].sh_flags & SHF_ALLOC) return rtDwarfUnwind_EhData((uint8_t const *)pThis->pvBits + pThis->paShdrs[iShdr].sh_addr, pThis->paShdrs[iShdr].sh_size, pThis->paShdrs[iShdr].sh_addr, iSeg, off, uRva, pState, pThis->Core.enmArch); } return VERR_DBG_NO_UNWIND_INFO; } /** * The ELF module operations. */ static RTLDROPS RTLDRELF_MID(s_rtldrElf,Ops) = { #if ELF_MODE == 32 "elf32", #elif ELF_MODE == 64 "elf64", #endif RTLDRELF_NAME(Close), NULL, /* Get Symbol */ RTLDRELF_NAME(Done), RTLDRELF_NAME(EnumSymbols), /* ext: */ RTLDRELF_NAME(GetImageSize), RTLDRELF_NAME(GetBits), RTLDRELF_NAME(Relocate), RTLDRELF_NAME(GetSymbolEx), NULL /*pfnQueryForwarderInfo*/, RTLDRELF_NAME(EnumDbgInfo), RTLDRELF_NAME(EnumSegments), RTLDRELF_NAME(LinkAddressToSegOffset), RTLDRELF_NAME(LinkAddressToRva), RTLDRELF_NAME(SegOffsetToRva), RTLDRELF_NAME(RvaToSegOffset), RTLDRELF_NAME(ReadDbgInfo), RTLDRELF_NAME(QueryProp), NULL /*pfnVerifySignature*/, rtldrELFLnxKModHashImage, RTLDRELF_NAME(UnwindFrame), 42 }; /** * Validates the ELF header. * * @returns iprt status code. * @param pEhdr Pointer to the ELF header. * @param cbRawImage The size of the raw image. * @param pszLogName The log name. * @param penmArch Where to return the architecture. * @param pErrInfo Where to return extended error info. Optional. */ static int RTLDRELF_NAME(ValidateElfHeader)(const Elf_Ehdr *pEhdr, uint64_t cbRawImage, const char *pszLogName, PRTLDRARCH penmArch, PRTERRINFO pErrInfo) { Log3(("RTLdrELF: e_ident: %.*Rhxs\n" "RTLdrELF: e_type: " FMT_ELF_HALF "\n" "RTLdrELF: e_version: " FMT_ELF_HALF "\n" "RTLdrELF: e_entry: " FMT_ELF_ADDR "\n" "RTLdrELF: e_phoff: " FMT_ELF_OFF "\n" "RTLdrELF: e_shoff: " FMT_ELF_OFF "\n" "RTLdrELF: e_flags: " FMT_ELF_WORD "\n" "RTLdrELF: e_ehsize: " FMT_ELF_HALF "\n" "RTLdrELF: e_phentsize: " FMT_ELF_HALF "\n" "RTLdrELF: e_phnum: " FMT_ELF_HALF "\n" "RTLdrELF: e_shentsize: " FMT_ELF_HALF "\n" "RTLdrELF: e_shnum: " FMT_ELF_HALF "\n" "RTLdrELF: e_shstrndx: " FMT_ELF_HALF "\n", RT_ELEMENTS(pEhdr->e_ident), &pEhdr->e_ident[0], pEhdr->e_type, pEhdr->e_version, pEhdr->e_entry, pEhdr->e_phoff, pEhdr->e_shoff,pEhdr->e_flags, pEhdr->e_ehsize, pEhdr->e_phentsize, pEhdr->e_phnum, pEhdr->e_shentsize, pEhdr->e_shnum, pEhdr->e_shstrndx)); if ( pEhdr->e_ident[EI_MAG0] != ELFMAG0 || pEhdr->e_ident[EI_MAG1] != ELFMAG1 || pEhdr->e_ident[EI_MAG2] != ELFMAG2 || pEhdr->e_ident[EI_MAG3] != ELFMAG3) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Invalid ELF magic (%.*Rhxs)", pszLogName, sizeof(pEhdr->e_ident), pEhdr->e_ident); if (pEhdr->e_ident[EI_CLASS] != RTLDRELF_SUFF(ELFCLASS)) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Invalid ELF class (%.*Rhxs)", pszLogName, sizeof(pEhdr->e_ident), pEhdr->e_ident); if (pEhdr->e_ident[EI_DATA] != ELFDATA2LSB) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_LDRELF_ODD_ENDIAN, "%s: ELF endian %x is unsupported", pszLogName, pEhdr->e_ident[EI_DATA]); if (pEhdr->e_version != EV_CURRENT) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_LDRELF_VERSION, "%s: ELF version %x is unsupported", pszLogName, pEhdr->e_version); if (sizeof(Elf_Ehdr) != pEhdr->e_ehsize) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Elf header e_ehsize is %d expected %d!", pszLogName, pEhdr->e_ehsize, sizeof(Elf_Ehdr)); if ( sizeof(Elf_Phdr) != pEhdr->e_phentsize && ( pEhdr->e_phnum != 0 || pEhdr->e_type == ET_DYN || pEhdr->e_type == ET_EXEC)) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Elf header e_phentsize is %d expected %d!", pszLogName, pEhdr->e_phentsize, sizeof(Elf_Phdr)); if (sizeof(Elf_Shdr) != pEhdr->e_shentsize) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Elf header e_shentsize is %d expected %d!", pszLogName, pEhdr->e_shentsize, sizeof(Elf_Shdr)); switch (pEhdr->e_type) { case ET_REL: case ET_EXEC: case ET_DYN: break; default: return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: image type %#x is not supported!", pszLogName, pEhdr->e_type); } switch (pEhdr->e_machine) { #if ELF_MODE == 32 case EM_386: case EM_486: *penmArch = RTLDRARCH_X86_32; break; #elif ELF_MODE == 64 case EM_X86_64: *penmArch = RTLDRARCH_AMD64; break; #endif default: return RTERRINFO_LOG_SET_F(pErrInfo, VERR_LDRELF_MACHINE, "%s: machine type %u is not supported!", pszLogName, pEhdr->e_machine); } if ( pEhdr->e_phoff < pEhdr->e_ehsize && !(pEhdr->e_phoff && pEhdr->e_phnum) && pEhdr->e_phnum) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: The program headers overlap with the ELF header! e_phoff=" FMT_ELF_OFF, pszLogName, pEhdr->e_phoff); if ( pEhdr->e_phoff + pEhdr->e_phnum * pEhdr->e_phentsize > cbRawImage || pEhdr->e_phoff + pEhdr->e_phnum * pEhdr->e_phentsize < pEhdr->e_phoff) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: The program headers extends beyond the file! e_phoff=" FMT_ELF_OFF " e_phnum=" FMT_ELF_HALF, pszLogName, pEhdr->e_phoff, pEhdr->e_phnum); if ( pEhdr->e_shoff < pEhdr->e_ehsize && !(pEhdr->e_shoff && pEhdr->e_shnum)) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: The section headers overlap with the ELF header! e_shoff=" FMT_ELF_OFF, pszLogName, pEhdr->e_shoff); if ( pEhdr->e_shoff + pEhdr->e_shnum * pEhdr->e_shentsize > cbRawImage || pEhdr->e_shoff + pEhdr->e_shnum * pEhdr->e_shentsize < pEhdr->e_shoff) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: The section headers extends beyond the file! e_shoff=" FMT_ELF_OFF " e_shnum=" FMT_ELF_HALF, pszLogName, pEhdr->e_shoff, pEhdr->e_shnum); if (pEhdr->e_shstrndx == 0 || pEhdr->e_shstrndx > pEhdr->e_shnum) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: The section headers string table is out of bounds! e_shstrndx=" FMT_ELF_HALF " e_shnum=" FMT_ELF_HALF, pszLogName, pEhdr->e_shstrndx, pEhdr->e_shnum); return VINF_SUCCESS; } /** * Gets the section header name. * * @returns pszName. * @param pEhdr The elf header. * @param offName The offset of the section header name. * @param pszName Where to store the name. * @param cbName The size of the buffer pointed to by pszName. */ const char *RTLDRELF_NAME(GetSHdrName)(PRTLDRMODELF pModElf, Elf_Word offName, char *pszName, size_t cbName) { RTFOFF off = pModElf->paShdrs[pModElf->Ehdr.e_shstrndx].sh_offset + offName; int rc = pModElf->Core.pReader->pfnRead(pModElf->Core.pReader, pszName, cbName - 1, off); if (RT_FAILURE(rc)) { /* read by for byte. */ for (unsigned i = 0; i < cbName; i++, off++) { rc = pModElf->Core.pReader->pfnRead(pModElf->Core.pReader, pszName + i, 1, off); if (RT_FAILURE(rc)) { pszName[i] = '\0'; break; } } } pszName[cbName - 1] = '\0'; return pszName; } /** * Validates a section header. * * @returns iprt status code. * @param pModElf Pointer to the module structure. * @param iShdr The index of section header which should be validated. * The section headers are found in the pModElf->paShdrs array. * @param cbRawImage The size of the raw image. * @param pszLogName The log name. * @param pErrInfo Where to return extended error info. Optional. */ static int RTLDRELF_NAME(ValidateSectionHeader)(PRTLDRMODELF pModElf, unsigned iShdr, uint64_t cbRawImage, const char *pszLogName, PRTERRINFO pErrInfo) { const Elf_Shdr *pShdr = &pModElf->paShdrs[iShdr]; char szSectionName[80]; NOREF(szSectionName); Log3(("RTLdrELF: Section Header #%d:\n" "RTLdrELF: sh_name: " FMT_ELF_WORD " - %s\n" "RTLdrELF: sh_type: " FMT_ELF_WORD " (%s)\n" "RTLdrELF: sh_flags: " FMT_ELF_XWORD "\n" "RTLdrELF: sh_addr: " FMT_ELF_ADDR "\n" "RTLdrELF: sh_offset: " FMT_ELF_OFF "\n" "RTLdrELF: sh_size: " FMT_ELF_XWORD "\n" "RTLdrELF: sh_link: " FMT_ELF_WORD "\n" "RTLdrELF: sh_info: " FMT_ELF_WORD "\n" "RTLdrELF: sh_addralign: " FMT_ELF_XWORD "\n" "RTLdrELF: sh_entsize: " FMT_ELF_XWORD "\n", iShdr, pShdr->sh_name, RTLDRELF_NAME(GetSHdrName)(pModElf, pShdr->sh_name, szSectionName, sizeof(szSectionName)), pShdr->sh_type, rtldrElfGetShdrType(pShdr->sh_type), pShdr->sh_flags, pShdr->sh_addr, pShdr->sh_offset, pShdr->sh_size, pShdr->sh_link, pShdr->sh_info, pShdr->sh_addralign, pShdr->sh_entsize)); if (iShdr == 0) { if ( pShdr->sh_name != 0 || pShdr->sh_type != SHT_NULL || pShdr->sh_flags != 0 || pShdr->sh_addr != 0 || pShdr->sh_size != 0 || pShdr->sh_offset != 0 || pShdr->sh_link != SHN_UNDEF || pShdr->sh_addralign != 0 || pShdr->sh_entsize != 0 ) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Bad #0 section: %.*Rhxs", pszLogName, sizeof(*pShdr), pShdr); return VINF_SUCCESS; } if (pShdr->sh_name >= pModElf->cbShStr) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Shdr #%d: sh_name (%d) is beyond the end of the section header string table (%d)!", pszLogName, iShdr, pShdr->sh_name, pModElf->cbShStr); if (pShdr->sh_link >= pModElf->Ehdr.e_shnum) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Shdr #%d: sh_link (%d) is beyond the end of the section table (%d)!", pszLogName, iShdr, pShdr->sh_link, pModElf->Ehdr.e_shnum); switch (pShdr->sh_type) { /** @todo find specs and check up which sh_info fields indicates section table entries */ case 12301230: if (pShdr->sh_info >= pModElf->Ehdr.e_shnum) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Shdr #%d: sh_info (%d) is beyond the end of the section table (%d)!", pszLogName, iShdr, pShdr->sh_link, pModElf->Ehdr.e_shnum); break; case SHT_NULL: break; case SHT_PROGBITS: case SHT_SYMTAB: case SHT_STRTAB: case SHT_RELA: case SHT_HASH: case SHT_DYNAMIC: case SHT_NOTE: case SHT_NOBITS: case SHT_REL: case SHT_SHLIB: case SHT_DYNSYM: /* * For these types sh_info doesn't have any special meaning, or anything which * we need/can validate now. */ break; default: Log(("RTLdrELF: %s: Warning, unknown type %d!\n", pszLogName, pShdr->sh_type)); break; } if ( pShdr->sh_type != SHT_NOBITS && pShdr->sh_size) { uint64_t offEnd = pShdr->sh_offset + pShdr->sh_size; if ( offEnd > cbRawImage || offEnd < (uint64_t)pShdr->sh_offset) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Shdr #%d: sh_offset (" FMT_ELF_OFF ") + sh_size (" FMT_ELF_XWORD " = %RX64) is beyond the end of the file (%RX64)!", pszLogName, iShdr, pShdr->sh_offset, pShdr->sh_size, offEnd, cbRawImage); if (pShdr->sh_offset < sizeof(Elf_Ehdr)) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Shdr #%d: sh_offset (" FMT_ELF_OFF ") + sh_size (" FMT_ELF_XWORD ") is starting in the ELF header!", pszLogName, iShdr, pShdr->sh_offset, pShdr->sh_size); } return VINF_SUCCESS; } /** * Process the section headers. * * @returns iprt status code. * @param pModElf Pointer to the module structure. * @param paShdrs The section headers. * @param cbRawImage The size of the raw image. * @param pszLogName The log name. * @param pErrInfo Where to return extended error info. Optional. */ static int RTLDRELF_NAME(ValidateAndProcessSectionHeaders)(PRTLDRMODELF pModElf, Elf_Shdr *paShdrs, uint64_t cbRawImage, const char *pszLogName, PRTERRINFO pErrInfo) { Elf_Addr uNextAddr = 0; for (unsigned i = 0; i < pModElf->Ehdr.e_shnum; i++) { int rc = RTLDRELF_NAME(ValidateSectionHeader)(pModElf, i, cbRawImage, pszLogName, pErrInfo); if (RT_FAILURE(rc)) return rc; /* * We're looking for symbol tables. */ if (paShdrs[i].sh_type == SHT_SYMTAB) { if (pModElf->Rel.iSymSh != ~0U) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_LDRELF_MULTIPLE_SYMTABS, "%s: Multiple symbol tabs! iSymSh=%d i=%d", pszLogName, pModElf->Rel.iSymSh, i); pModElf->Rel.iSymSh = i; pModElf->Rel.cSyms = (unsigned)(paShdrs[i].sh_size / sizeof(Elf_Sym)); AssertBreakStmt(pModElf->Rel.cSyms == paShdrs[i].sh_size / sizeof(Elf_Sym), rc = VERR_IMAGE_TOO_BIG); pModElf->Rel.iStrSh = paShdrs[i].sh_link; pModElf->Rel.cbStr = (unsigned)paShdrs[pModElf->Rel.iStrSh].sh_size; AssertBreakStmt(pModElf->Rel.cbStr == paShdrs[pModElf->Rel.iStrSh].sh_size, rc = VERR_IMAGE_TOO_BIG); } else if (paShdrs[i].sh_type == SHT_DYNSYM) { if (pModElf->Dyn.iSymSh != ~0U) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_LDRELF_MULTIPLE_SYMTABS, "%s: Multiple dynamic symbol tabs! iSymSh=%d i=%d", pszLogName, pModElf->Dyn.iSymSh, i); if (pModElf->Ehdr.e_type != ET_DYN && pModElf->Ehdr.e_type != ET_EXEC) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Unexpected SHT_DYNSYM (i=%d) for e_type=%d", pszLogName, i, pModElf->Ehdr.e_type); pModElf->Dyn.iSymSh = i; pModElf->Dyn.cSyms = (unsigned)(paShdrs[i].sh_size / sizeof(Elf_Sym)); AssertBreakStmt(pModElf->Dyn.cSyms == paShdrs[i].sh_size / sizeof(Elf_Sym), rc = VERR_IMAGE_TOO_BIG); pModElf->Dyn.iStrSh = paShdrs[i].sh_link; pModElf->Dyn.cbStr = (unsigned)paShdrs[pModElf->Dyn.iStrSh].sh_size; AssertBreakStmt(pModElf->Dyn.cbStr == paShdrs[pModElf->Dyn.iStrSh].sh_size, rc = VERR_IMAGE_TOO_BIG); } /* * We're also look for the dynamic section. */ else if (paShdrs[i].sh_type == SHT_DYNAMIC) { if (pModElf->iShDynamic != ~0U) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Multiple dynamic sections! iShDynamic=%d i=%d", pszLogName, pModElf->iShDynamic, i); if (pModElf->Ehdr.e_type != ET_DYN && pModElf->Ehdr.e_type != ET_EXEC) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Unexpected SHT_DYNAMIC (i=%d) for e_type=%d", pszLogName, i, pModElf->Ehdr.e_type); if (paShdrs[i].sh_entsize != sizeof(Elf_Dyn)) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: SHT_DYNAMIC (i=%d) sh_entsize=" FMT_ELF_XWORD ", expected %#zx", pszLogName, i, paShdrs[i].sh_entsize, sizeof(Elf_Dyn)); pModElf->iShDynamic = i; Elf_Xword const cDynamic = paShdrs[i].sh_size / sizeof(Elf_Dyn); if (cDynamic > _64K || cDynamic < 2) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: SHT_DYNAMIC (i=%d) sh_size=" FMT_ELF_XWORD " is out of range (2..64K)", pszLogName, i, paShdrs[i].sh_size); pModElf->cDynamic = (unsigned)cDynamic; } /* * Special checks for the section string table. */ if (i == pModElf->Ehdr.e_shstrndx) { if (paShdrs[i].sh_type != SHT_STRTAB) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Section header string table is not a SHT_STRTAB: %#x", pszLogName, paShdrs[i].sh_type); if (paShdrs[i].sh_size == 0) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Section header string table is empty", pszLogName); } /* * Kluge for the .data..percpu segment in 64-bit linux kernels. */ if (paShdrs[i].sh_flags & SHF_ALLOC) { if ( paShdrs[i].sh_addr == 0 && paShdrs[i].sh_addr < uNextAddr) { Elf_Addr uAddr = RT_ALIGN_T(uNextAddr, paShdrs[i].sh_addralign, Elf_Addr); Log(("RTLdrElf: Out of order section #%d; adjusting sh_addr from " FMT_ELF_ADDR " to " FMT_ELF_ADDR "\n", i, paShdrs[i].sh_addr, uAddr)); paShdrs[i].sh_addr = uAddr; } uNextAddr = paShdrs[i].sh_addr + paShdrs[i].sh_size; } } /* for each section header */ return VINF_SUCCESS; } /** * Process the section headers. * * @returns iprt status code. * @param pModElf Pointer to the module structure. * @param paShdrs The section headers. * @param cbRawImage The size of the raw image. * @param pszLogName The log name. * @param pErrInfo Where to return extended error info. Optional. */ static int RTLDRELF_NAME(ValidateAndProcessDynamicInfo)(PRTLDRMODELF pModElf, uint64_t cbRawImage, uint32_t fFlags, const char *pszLogName, PRTERRINFO pErrInfo) { /* * Check preconditions. */ AssertReturn(pModElf->Ehdr.e_type == ET_DYN || pModElf->Ehdr.e_type == ET_EXEC, VERR_INTERNAL_ERROR_2); if (pModElf->Ehdr.e_phnum <= 1 || pModElf->Ehdr.e_phnum >= _32K) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: e_phnum=%u is out of bounds (2..32K)", pszLogName, pModElf->Ehdr.e_phnum); if (pModElf->iShDynamic == ~0U) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: no .dynamic section", pszLogName); AssertReturn(pModElf->cDynamic > 1 && pModElf->cDynamic <= _64K, VERR_INTERNAL_ERROR_3); /* ASSUME that the sections are ordered by address. That simplifies validation code further down. */ AssertReturn(pModElf->Ehdr.e_shnum >= 2, VERR_INTERNAL_ERROR_4); Elf_Shdr const *paShdrs = pModElf->paShdrs; Elf_Addr uPrevEnd = paShdrs[1].sh_addr + paShdrs[1].sh_size; for (unsigned i = 2; i < pModElf->Ehdr.e_shnum; i++) if (paShdrs[i].sh_flags & SHF_ALLOC) { if (uPrevEnd > paShdrs[i].sh_addr) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: section %u is out of order: uPrevEnd=" FMT_ELF_ADDR " sh_addr=" FMT_ELF_ADDR, pszLogName, i, uPrevEnd, paShdrs[i].sh_addr); uPrevEnd = paShdrs[i].sh_addr + paShdrs[i].sh_size; } /* Must have string and symbol tables. */ if (pModElf->Dyn.iStrSh == ~0U) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: No dynamic string table section", pszLogName); if (pModElf->Dyn.iSymSh == ~0U) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: No dynamic symbol table section", pszLogName); /* * Load the program headers. */ size_t const cbPhdrs = sizeof(pModElf->paPhdrs[0]) * pModElf->Ehdr.e_phnum; Elf_Phdr *paPhdrs = (Elf_Phdr *)RTMemAllocZ(cbPhdrs); pModElf->paPhdrs = paPhdrs; AssertReturn(paPhdrs, VERR_NO_MEMORY); int rc = pModElf->Core.pReader->pfnRead(pModElf->Core.pReader, paPhdrs, cbPhdrs, pModElf->Ehdr.e_phoff); if (RT_FAILURE(rc)) return RTERRINFO_LOG_SET_F(pErrInfo, rc, "%s: pfnRead(,,%#zx, " FMT_ELF_OFF ") -> %Rrc", pszLogName, cbPhdrs, pModElf->Ehdr.e_phoff, rc); /* * Validate them. */ unsigned cbPage = _4K; /** @todo generalize architecture specific stuff using its own code template header. */ switch (pModElf->Core.enmArch) { case RTLDRARCH_AMD64: case RTLDRARCH_X86_32: break; default: AssertFailedBreak(/** @todo page size for got.plt hacks */); } unsigned iLoad = 0; unsigned iLoadShdr = 1; /* ASSUMES ordered (checked above). */ unsigned cDynamic = 0; Elf_Addr cbImage = 0; Elf_Addr uLinkAddress = ~(Elf_Addr)0; for (unsigned i = 0; i < pModElf->Ehdr.e_phnum; i++) { const Elf_Phdr * const pPhdr = &paPhdrs[i]; Log3(("RTLdrELF: Program Header #%d:\n" "RTLdrELF: p_type: " FMT_ELF_WORD " (%s)\n" "RTLdrELF: p_flags: " FMT_ELF_WORD "\n" "RTLdrELF: p_offset: " FMT_ELF_OFF "\n" "RTLdrELF: p_vaddr: " FMT_ELF_ADDR "\n" "RTLdrELF: p_paddr: " FMT_ELF_ADDR "\n" "RTLdrELF: p_filesz: " FMT_ELF_XWORD "\n" "RTLdrELF: p_memsz: " FMT_ELF_XWORD "\n" "RTLdrELF: p_align: " FMT_ELF_XWORD "\n", i, pPhdr->p_type, rtldrElfGetPhdrType(pPhdr->p_type), pPhdr->p_flags, pPhdr->p_offset, pPhdr->p_vaddr, pPhdr->p_paddr, pPhdr->p_filesz, pPhdr->p_memsz, pPhdr->p_align)); if (pPhdr->p_type == DT_NULL) continue; if ( pPhdr->p_filesz != 0 && ( pPhdr->p_offset >= cbRawImage || pPhdr->p_filesz > cbRawImage || pPhdr->p_offset + pPhdr->p_filesz > cbRawImage)) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Prog Hdr #%u: bogus p_offset=" FMT_ELF_OFF " & p_filesz=" FMT_ELF_XWORD " (file size %#RX64)", pszLogName, i, pPhdr->p_offset, pPhdr->p_filesz, cbRawImage); if (pPhdr->p_flags & ~(Elf64_Word)(PF_X | PF_R | PF_W)) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Prog Hdr #%u: bogus p_flags=" FMT_ELF_WORD, pszLogName, i, pPhdr->p_flags); if (!RT_IS_POWER_OF_TWO(pPhdr->p_align)) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Prog Hdr #%u: bogus p_align=" FMT_ELF_XWORD, pszLogName, i, pPhdr->p_align); if ( pPhdr->p_align > 1 && pPhdr->p_memsz > 0 && pPhdr->p_filesz > 0 && (pPhdr->p_offset & (pPhdr->p_align - 1)) != (pPhdr->p_vaddr & (pPhdr->p_align - 1))) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Prog Hdr #%u: misaligned p_offset=" FMT_ELF_OFF " p_vaddr=" FMT_ELF_ADDR " p_align=" FMT_ELF_XWORD, pszLogName, i, pPhdr->p_offset, pPhdr->p_vaddr, pPhdr->p_align); /* Do some type specfic checks: */ switch (pPhdr->p_type) { case PT_LOAD: { if (pPhdr->p_memsz < pPhdr->p_filesz) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Prog Hdr #%u/LOAD#%u: bogus p_memsz=" FMT_ELF_XWORD " or p_filesz=" FMT_ELF_XWORD, pszLogName, i, iLoad, pPhdr->p_memsz, pPhdr->p_filesz); cbImage = pPhdr->p_vaddr + pPhdr->p_memsz; if (iLoad == 0) uLinkAddress = pPhdr->p_vaddr; /* Find the corresponding sections, checking their addresses and file offsets since the rest of the code is still section based rather than using program headers as it should... */ Elf_Off off = pPhdr->p_offset; Elf_Addr uAddr = pPhdr->p_vaddr; Elf_Xword cbMem = pPhdr->p_memsz; Elf_Xword cbFile = pPhdr->p_filesz; /* HACK to allow loading isolinux-debug.elf where program headers aren't sorted by virtual address. */ if ( (fFlags & RTLDR_O_FOR_DEBUG) && uAddr != paShdrs[iLoadShdr].sh_addr) { for (unsigned iShdr = 1; iShdr < pModElf->Ehdr.e_shnum; iShdr++) if (uAddr == paShdrs[iShdr].sh_addr) { iLoadShdr = iShdr; break; } } while (cbMem > 0) { if (iLoadShdr < pModElf->Ehdr.e_shnum) { /* likely */ } else if (iLoadShdr == pModElf->Ehdr.e_shnum) { /** @todo anything else to check here? */ iLoadShdr++; break; } else return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Prog Hdr #%u/LOAD#%u: Out of sections at " FMT_ELF_ADDR " LB " FMT_ELF_XWORD, pszLogName, i, iLoad, uAddr, cbMem); if (!(paShdrs[iLoadShdr].sh_flags & SHF_ALLOC)) { if ( paShdrs[iLoadShdr].sh_type != SHT_NOBITS && paShdrs[iLoadShdr].sh_size > 0 && off < paShdrs[iLoadShdr].sh_offset + paShdrs[iLoadShdr].sh_size && paShdrs[iLoadShdr].sh_offset < off + cbMem) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Prog Hdr #%u/LOAD#%u: Overlaps with !SHF_ALLOC section at " FMT_ELF_OFF " LB " FMT_ELF_XWORD, pszLogName, i, iLoad, paShdrs[iLoadShdr].sh_offset, paShdrs[iLoadShdr].sh_size); pModElf->paShdrExtras[iLoadShdr].idxPhdr = UINT16_MAX; iLoadShdr++; continue; } if (uAddr != paShdrs[iLoadShdr].sh_addr) { /* Before the first section we expect headers to be loaded, so that the file is simply mapped from file offset zero. */ if ( iLoadShdr == 1 && iLoad == 0 && paShdrs[1].sh_addr == paShdrs[1].sh_offset && cbFile >= paShdrs[1].sh_offset && cbMem >= paShdrs[1].sh_offset) { /* Modify paShdrs[0] to describe the gap. ".elf.headers" */ pModElf->iFirstSect = 0; pModElf->paShdrs[0].sh_name = 0; pModElf->paShdrs[0].sh_type = SHT_PROGBITS; pModElf->paShdrs[0].sh_flags = SHF_ALLOC | (pPhdr->p_flags & PF_W ? SHF_WRITE : 0) | (pPhdr->p_flags & PF_X ? SHF_EXECINSTR : 0); pModElf->paShdrs[0].sh_addr = uAddr; pModElf->paShdrs[0].sh_offset = off; pModElf->paShdrs[0].sh_size = paShdrs[1].sh_offset; pModElf->paShdrs[0].sh_link = 0; pModElf->paShdrs[0].sh_info = 0; pModElf->paShdrs[0].sh_addralign = pPhdr->p_align; pModElf->paShdrs[0].sh_entsize = 0; *(Elf_Shdr *)pModElf->paOrgShdrs = pModElf->paShdrs[0]; /* (necessary for segment enumeration) */ uAddr += paShdrs[1].sh_offset; cbMem -= paShdrs[1].sh_offset; cbFile -= paShdrs[1].sh_offset; off = paShdrs[1].sh_offset; } /* Alignment padding? Allow up to a page size. */ else if ( paShdrs[iLoadShdr].sh_addr > uAddr && paShdrs[iLoadShdr].sh_addr - uAddr < RT_MAX(paShdrs[iLoadShdr].sh_addralign, cbPage /*got.plt hack*/)) { Elf_Xword cbAlignPadding = paShdrs[iLoadShdr].sh_addr - uAddr; if (cbAlignPadding >= cbMem) break; cbMem -= cbAlignPadding; uAddr += cbAlignPadding; if (cbFile > cbAlignPadding) { off += cbAlignPadding; cbFile -= cbAlignPadding; } else { off += cbFile; cbFile = 0; } } } if ( uAddr == paShdrs[iLoadShdr].sh_addr && cbMem >= paShdrs[iLoadShdr].sh_size && ( paShdrs[iLoadShdr].sh_type != SHT_NOBITS ? off == paShdrs[iLoadShdr].sh_offset && cbFile >= paShdrs[iLoadShdr].sh_size /* this might be too strict... */ : cbFile == 0 || cbMem > paShdrs[iLoadShdr].sh_size /* isolinux.elf: linker merge no-bits and progbits sections */) ) { if ( paShdrs[iLoadShdr].sh_type != SHT_NOBITS || cbFile != 0) { off += paShdrs[iLoadShdr].sh_size; cbFile -= paShdrs[iLoadShdr].sh_size; } uAddr += paShdrs[iLoadShdr].sh_size; cbMem -= paShdrs[iLoadShdr].sh_size; } else return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Prog Hdr #%u/LOAD#%u: Mismatch at " FMT_ELF_ADDR " LB " FMT_ELF_XWORD " (file " FMT_ELF_OFF " LB " FMT_ELF_XWORD ") with section #%u " FMT_ELF_ADDR " LB " FMT_ELF_XWORD " (file " FMT_ELF_OFF " sh_type=" FMT_ELF_WORD ")", pszLogName, i, iLoad, uAddr, cbMem, off, cbFile, iLoadShdr, paShdrs[iLoadShdr].sh_addr, paShdrs[iLoadShdr].sh_size, paShdrs[iLoadShdr].sh_offset, paShdrs[iLoadShdr].sh_type); pModElf->paShdrExtras[iLoadShdr].idxPhdr = iLoad; iLoadShdr++; } /* section loop */ iLoad++; break; } case PT_DYNAMIC: { const Elf_Shdr *pShdr = &pModElf->paShdrs[pModElf->iShDynamic]; if (pPhdr->p_offset != pShdr->sh_offset) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Prog Hdr #%u/DYNAMIC: p_offset=" FMT_ELF_OFF " expected " FMT_ELF_OFF, pszLogName, i, pPhdr->p_offset, pShdr->sh_offset); if (RT_MAX(pPhdr->p_memsz, pPhdr->p_filesz) != pShdr->sh_size) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Prog Hdr #%u/DYNAMIC: expected " FMT_ELF_XWORD " for RT_MAX(p_memsz=" FMT_ELF_XWORD ", p_filesz=" FMT_ELF_XWORD ")", pszLogName, i, pShdr->sh_size, pPhdr->p_memsz, pPhdr->p_filesz); cDynamic++; break; } } } if (iLoad == 0) return RTERRINFO_LOG_SET_F(pErrInfo, rc, "%s: No PT_LOAD program headers", pszLogName); if (cDynamic != 1) return RTERRINFO_LOG_SET_F(pErrInfo, rc, "%s: No program header for the DYNAMIC section", pszLogName); cbImage -= uLinkAddress; pModElf->cbImage = (uint64_t)cbImage; pModElf->LinkAddress = uLinkAddress; AssertReturn(pModElf->cbImage == cbImage, VERR_INTERNAL_ERROR_5); Log3(("RTLdrELF: LinkAddress=" FMT_ELF_ADDR " cbImage=" FMT_ELF_ADDR " (from PT_LOAD)\n", uLinkAddress, cbImage)); for (; iLoadShdr < pModElf->Ehdr.e_shnum; iLoadShdr++) if ( !(paShdrs[iLoadShdr].sh_flags & SHF_ALLOC) || paShdrs[iLoadShdr].sh_size == 0) pModElf->paShdrExtras[iLoadShdr].idxPhdr = UINT16_MAX; else return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: No PT_LOAD for section #%u " FMT_ELF_ADDR " LB " FMT_ELF_XWORD " (file " FMT_ELF_OFF " sh_type=" FMT_ELF_WORD ")", pszLogName, iLoadShdr, paShdrs[iLoadShdr].sh_addr, paShdrs[iLoadShdr].sh_size, paShdrs[iLoadShdr].sh_offset, paShdrs[iLoadShdr].sh_type); /* * Load and validate the dynamic table. We have got / will get most of the * info we need from the section table, so we must make sure this matches up. */ Log3(("RTLdrELF: Dynamic section - %u entries\n", pModElf->cDynamic)); size_t const cbDynamic = pModElf->cDynamic * sizeof(pModElf->paDynamic[0]); Elf_Dyn * const paDynamic = (Elf_Dyn *)RTMemAlloc(cbDynamic); AssertReturn(paDynamic, VERR_NO_MEMORY); pModElf->paDynamic = paDynamic; rc = pModElf->Core.pReader->pfnRead(pModElf->Core.pReader, paDynamic, cbDynamic, paShdrs[pModElf->iShDynamic].sh_offset); if (RT_FAILURE(rc)) return RTERRINFO_LOG_SET_F(pErrInfo, rc, "%s: pfnRead(,,%#zx, " FMT_ELF_OFF ") -> %Rrc", pszLogName, cbDynamic, paShdrs[pModElf->iShDynamic].sh_offset, rc); for (uint32_t i = 0; i < pModElf->cDynamic; i++) { #define LOG_VALIDATE_PTR_RET(szName) do { \ Log3(("RTLdrELF: DT[%u]: %16s " FMT_ELF_ADDR "\n", i, szName, paDynamic[i].d_un.d_ptr)); \ if ((uint64_t)paDynamic[i].d_un.d_ptr - uLinkAddress < cbImage) { /* likely */ } \ else return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT[%u]/" szName ": Invalid address " FMT_ELF_ADDR " (valid range: " FMT_ELF_ADDR " LB " FMT_ELF_ADDR ")", \ pszLogName, i, paDynamic[i].d_un.d_ptr, uLinkAddress, cbImage); \ } while (0) #define LOG_VALIDATE_PTR_VAL_RET(szName, uExpected) do { \ Log3(("RTLdrELF: DT[%u]: %16s " FMT_ELF_ADDR "\n", i, szName, (uint64_t)paDynamic[i].d_un.d_ptr)); \ if (paDynamic[i].d_un.d_ptr == (Elf_Addr)(uExpected)) { /* likely */ } \ else return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT[%u]/" szName ": " FMT_ELF_ADDR ", expected " FMT_ELF_ADDR, \ pszLogName, i, paDynamic[i].d_un.d_ptr, (Elf_Addr)(uExpected)); \ } while (0) #define LOG_VALIDATE_STR_RET(szName) do { \ Log3(("RTLdrELF: DT[%u]: %16s %#RX64\n", i, szName, (uint64_t)paDynamic[i].d_un.d_val)); \ if ((uint64_t)paDynamic[i].d_un.d_val < pModElf->Dyn.cbStr) { /* likely */ } \ else return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT[%u]/" szName ": Invalid string table offset %#RX64 (max %#x)", \ pszLogName, i, (uint64_t)paDynamic[i].d_un.d_val, pModElf->Dyn.cbStr); \ } while (0) #define LOG_VALIDATE_VAL_RET(szName, uExpected) do { \ Log3(("RTLdrELF: DT[%u]: %16s %#RX64\n", i, szName, (uint64_t)paDynamic[i].d_un.d_val)); \ if ((uint64_t)paDynamic[i].d_un.d_val == (uint64_t)(uExpected)) { /* likely */ } \ else return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT[%u]/" szName ": %#RX64, expected %#RX64", \ pszLogName, i, (uint64_t)paDynamic[i].d_un.d_val, (uint64_t)(uExpected)); \ } while (0) #define SET_RELOC_TYPE_RET(a_szName, a_uType) do { \ if (pModElf->DynInfo.uRelocType == 0 || pModElf->DynInfo.uRelocType == (a_uType)) \ pModElf->DynInfo.uRelocType = (a_uType); \ else return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT[%u]/" a_szName ": Mixing DT_RELA and DT_REL", pszLogName, i); \ } while (0) #define SET_INFO_FIELD_RET(a_szName, a_Field, a_Value, a_UnsetValue, a_szFmt) do { \ if ((a_Field) == (a_UnsetValue) && (a_Value) != (a_UnsetValue)) \ (a_Field) = (a_Value); /* likely */ \ else if ((a_Field) != (a_UnsetValue)) \ return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT[%u]/" a_szName ": Multiple entries (first value " a_szFmt ", second " a_szFmt ")", pszLogName, i, (a_Field), (a_Value)); \ else if ((a_Value) != (a_UnsetValue)) \ return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT[%u]/" a_szName ": Unexpected value " a_szFmt, pszLogName, i, (a_Value)); \ } while (0) #define FIND_MATCHING_SECTION_RET(a_szName, a_ExtraMatchExpr, a_idxShFieldToSet) do { \ unsigned iSh; \ for (iSh = 1; iSh < pModElf->Ehdr.e_shnum; iSh++) \ if ( paShdrs[iSh].sh_addr == paDynamic[i].d_un.d_ptr \ && (a_ExtraMatchExpr)) \ { \ (a_idxShFieldToSet) = iSh; \ if (pModElf->paShdrExtras[iSh].idxDt != UINT16_MAX) \ return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, \ "%s: DT[%u]/" a_szName ": section #%u (" FMT_ELF_ADDR ") already referenced by DT[%u]", \ pszLogName, i, iSh, paShdrs[iSh].sh_addr, pModElf->paShdrExtras[iSh].idxDt); \ pModElf->paShdrExtras[iSh].idxDt = i; \ pModElf->paShdrExtras[iSh].uDtTag = (uint32_t)paDynamic[i].d_tag; \ break; \ } \ if (iSh < pModElf->Ehdr.e_shnum) { /* likely */ } \ else return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT[%u]/" a_szName ": No matching section for " FMT_ELF_ADDR, pszLogName, i, paDynamic[i].d_un.d_ptr); \ } while (0) #define ONLY_FOR_DEBUG_OR_VALIDATION_RET(a_szName) do { \ if (fFlags & (RTLDR_O_FOR_DEBUG | RTLDR_O_FOR_VALIDATION)) { /* likely */ } \ else return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT[%u]/" a_szName ": Not supported (" FMT_ELF_ADDR ")", pszLogName, i, paDynamic[i].d_un.d_ptr); \ } while (0) #define LOG_NON_VALUE_ENTRY(a_szName) Log3(("RTLdrELF: DT[%u]: %16s (%#RX64)\n", i, a_szName, (uint64_t)paDynamic[i].d_un.d_val)) switch (paDynamic[i].d_tag) { case DT_NULL: LOG_NON_VALUE_ENTRY("DT_NULL"); for (unsigned iNull = i + 1; iNull < pModElf->cDynamic; iNull++) if (paDynamic[i].d_tag == DT_NULL) /* Not technically a bug, but let's try being extremely strict for now */ LOG_NON_VALUE_ENTRY("DT_NULL"); else if (!(fFlags & (RTLDR_O_FOR_DEBUG | RTLDR_O_FOR_VALIDATION))) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT[%u]/DT_NULL: Dynamic section isn't zero padded (extra #%u of #%u)", pszLogName, i, iNull - i, pModElf->cDynamic - i); i = pModElf->cDynamic; break; case DT_NEEDED: LOG_VALIDATE_STR_RET("DT_NEEDED"); break; case DT_PLTRELSZ: Log3(("RTLdrELF: DT[%u]: %16s %#RX64 bytes\n", i, "DT_PLTRELSZ", (uint64_t)paDynamic[i].d_un.d_val)); SET_INFO_FIELD_RET("DT_PLTRELSZ", pModElf->DynInfo.cbJmpRelocs, (Elf_Xword)paDynamic[i].d_un.d_val, 0, FMT_ELF_XWORD); break; case DT_PLTGOT: LOG_VALIDATE_PTR_RET("DT_PLTGOT"); break; case DT_HASH: LOG_VALIDATE_PTR_RET("DT_HASH"); break; case DT_STRTAB: LOG_VALIDATE_PTR_VAL_RET("DT_STRTAB", paShdrs[pModElf->Dyn.iStrSh].sh_addr); pModElf->paShdrExtras[pModElf->Dyn.iStrSh].idxDt = i; pModElf->paShdrExtras[pModElf->Dyn.iSymSh].uDtTag = DT_STRTAB; break; case DT_SYMTAB: LOG_VALIDATE_PTR_VAL_RET("DT_SYMTAB", paShdrs[pModElf->Dyn.iSymSh].sh_addr); pModElf->paShdrExtras[pModElf->Dyn.iSymSh].idxDt = i; pModElf->paShdrExtras[pModElf->Dyn.iSymSh].uDtTag = DT_SYMTAB; break; case DT_RELA: LOG_VALIDATE_PTR_RET("DT_RELA"); SET_RELOC_TYPE_RET("DT_RELA", DT_RELA); SET_INFO_FIELD_RET("DT_RELA", pModElf->DynInfo.uPtrRelocs, paDynamic[i].d_un.d_ptr, ~(Elf_Addr)0, FMT_ELF_ADDR); FIND_MATCHING_SECTION_RET("DT_RELA", paShdrs[iSh].sh_type == SHT_RELA, pModElf->DynInfo.idxShRelocs); break; case DT_RELASZ: Log3(("RTLdrELF: DT[%u]: %16s %#RX64 bytes\n", i, "DT_RELASZ", (uint64_t)paDynamic[i].d_un.d_val)); SET_RELOC_TYPE_RET("DT_RELASZ", DT_RELA); SET_INFO_FIELD_RET("DT_RELASZ", pModElf->DynInfo.cbRelocs, (Elf_Xword)paDynamic[i].d_un.d_val, 0, FMT_ELF_XWORD); break; case DT_RELAENT: LOG_VALIDATE_VAL_RET("DT_RELAENT", sizeof(Elf_Rela)); SET_RELOC_TYPE_RET("DT_RELAENT", DT_RELA); SET_INFO_FIELD_RET("DT_RELAENT", pModElf->DynInfo.cbRelocEntry, (unsigned)sizeof(Elf_Rela), 0, "%u"); break; case DT_STRSZ: LOG_VALIDATE_VAL_RET("DT_STRSZ", pModElf->Dyn.cbStr); break; case DT_SYMENT: LOG_VALIDATE_VAL_RET("DT_SYMENT", sizeof(Elf_Sym)); break; case DT_INIT: LOG_VALIDATE_PTR_RET("DT_INIT"); ONLY_FOR_DEBUG_OR_VALIDATION_RET("DT_INIT"); break; case DT_FINI: LOG_VALIDATE_PTR_RET("DT_FINI"); ONLY_FOR_DEBUG_OR_VALIDATION_RET("DT_FINI"); break; case DT_SONAME: LOG_VALIDATE_STR_RET("DT_SONAME"); break; case DT_RPATH: LOG_VALIDATE_STR_RET("DT_RPATH"); break; case DT_SYMBOLIC: LOG_NON_VALUE_ENTRY("DT_SYMBOLIC"); break; case DT_REL: LOG_VALIDATE_PTR_RET("DT_REL"); SET_RELOC_TYPE_RET("DT_REL", DT_REL); SET_INFO_FIELD_RET("DT_REL", pModElf->DynInfo.uPtrRelocs, paDynamic[i].d_un.d_ptr, ~(Elf_Addr)0, FMT_ELF_ADDR); FIND_MATCHING_SECTION_RET("DT_REL", paShdrs[iSh].sh_type == SHT_REL, pModElf->DynInfo.idxShRelocs); break; case DT_RELSZ: Log3(("RTLdrELF: DT[%u]: %16s %#RX64 bytes\n", i, "DT_RELSZ", (uint64_t)paDynamic[i].d_un.d_val)); SET_RELOC_TYPE_RET("DT_RELSZ", DT_REL); SET_INFO_FIELD_RET("DT_RELSZ", pModElf->DynInfo.cbRelocs, (Elf_Xword)paDynamic[i].d_un.d_val, 0, FMT_ELF_XWORD); break; case DT_RELENT: LOG_VALIDATE_VAL_RET("DT_RELENT", sizeof(Elf_Rel)); SET_RELOC_TYPE_RET("DT_RELENT", DT_REL); SET_INFO_FIELD_RET("DT_RELENT", pModElf->DynInfo.cbRelocEntry, (unsigned)sizeof(Elf_Rel), 0, "%u"); break; case DT_PLTREL: if (paDynamic[i].d_un.d_val != DT_RELA && paDynamic[i].d_un.d_val != DT_REL) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT[%u]/DT_PLTREL: Invalid value %#RX64", pszLogName, i, (uint64_t)paDynamic[i].d_un.d_val); Log3(("RTLdrELF: DT[%u]: %16s DT_REL%s\n", i, "DT_PLTREL", paDynamic[i].d_un.d_val == DT_RELA ? "A" : "")); SET_INFO_FIELD_RET("DT_PLTREL", pModElf->DynInfo.uJmpRelocType, (unsigned)paDynamic[i].d_un.d_val, 0, "%u"); break; case DT_DEBUG: /* * DT_DEBUG is filled in by the dynamic linker to point a debugger to the head of the link map, * it can point anywhere in userspace. For binaries not being executed it will be 0, * so there is nothing we can validate here (and it is not required as we don't use * this dynamic section). See https://ypl.coffee/dl-resolve-full-relro/ for more information. */ break; case DT_TEXTREL: LOG_NON_VALUE_ENTRY("DT_TEXTREL"); break; case DT_JMPREL: LOG_VALIDATE_PTR_RET("DT_JMPREL"); SET_INFO_FIELD_RET("DT_JMPREL", pModElf->DynInfo.uPtrJmpRelocs, paDynamic[i].d_un.d_ptr, ~(Elf_Addr)0, FMT_ELF_ADDR); FIND_MATCHING_SECTION_RET("DT_JMPREL", 1, pModElf->DynInfo.idxShJmpRelocs); break; case DT_BIND_NOW: LOG_NON_VALUE_ENTRY("DT_BIND_NOW"); break; case DT_INIT_ARRAY: LOG_VALIDATE_PTR_RET("DT_INIT_ARRAY"); ONLY_FOR_DEBUG_OR_VALIDATION_RET("DT_INIT_ARRAY"); break; case DT_FINI_ARRAY: LOG_VALIDATE_PTR_RET("DT_FINI_ARRAY"); ONLY_FOR_DEBUG_OR_VALIDATION_RET("DT_FINI_ARRAY"); break; case DT_INIT_ARRAYSZ: Log3(("RTLdrELF: DT[%u]: %16s %#RX64 bytes\n", i, "DT_INIT_ARRAYSZ", (uint64_t)paDynamic[i].d_un.d_val)); ONLY_FOR_DEBUG_OR_VALIDATION_RET("DT_INIT_ARRAYSZ"); break; case DT_FINI_ARRAYSZ: Log3(("RTLdrELF: DT[%u]: %16s %#RX64 bytes\n", i, "DT_FINI_ARRAYSZ", (uint64_t)paDynamic[i].d_un.d_val)); ONLY_FOR_DEBUG_OR_VALIDATION_RET("DT_FINI_ARRAYSZ"); break; case DT_RUNPATH: LOG_VALIDATE_STR_RET("DT_RUNPATH"); break; case DT_FLAGS: Log3(("RTLdrELF: DT[%u]: %16s %#RX64\n", i, "DT_FLAGS", (uint64_t)paDynamic[i].d_un.d_val)); break; case DT_PREINIT_ARRAY: LOG_VALIDATE_PTR_RET("DT_PREINIT_ARRAY"); ONLY_FOR_DEBUG_OR_VALIDATION_RET("DT_PREINIT_ARRAY"); break; case DT_PREINIT_ARRAYSZ: Log3(("RTLdrELF: DT[%u]: %16s %#RX64 bytes\n", i, "DT_PREINIT_ARRAYSZ", (uint64_t)paDynamic[i].d_un.d_val)); ONLY_FOR_DEBUG_OR_VALIDATION_RET("DT_PREINIT_ARRAYSZ"); break; default: if ( paDynamic[i].d_tag < DT_ENCODING || paDynamic[i].d_tag >= DT_LOOS || (paDynamic[i].d_tag & 1)) Log3(("RTLdrELF: DT[%u]: %#010RX64 %#RX64%s\n", i, (uint64_t)paDynamic[i].d_tag, (uint64_t)paDynamic[i].d_un.d_val, paDynamic[i].d_un.d_val >= DT_ENCODING ? " (val)" : "")); else { Log3(("RTLdrELF: DT[%u]: %#010RX64 " FMT_ELF_ADDR " (addr)\n", i, (uint64_t)paDynamic[i].d_tag, paDynamic[i].d_un.d_ptr)); if ((uint64_t)paDynamic[i].d_un.d_ptr - uLinkAddress >= cbImage) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT[%u]/%#RX64: Invalid address " FMT_ELF_ADDR " (valid range: " FMT_ELF_ADDR " LB " FMT_ELF_ADDR ")", pszLogName, i, (uint64_t)paDynamic[i].d_tag, paDynamic[i].d_un.d_ptr, uLinkAddress, cbImage); } break; } #undef LOG_VALIDATE_VAL_RET #undef LOG_VALIDATE_STR_RET #undef LOG_VALIDATE_PTR_VAL_RET #undef LOG_VALIDATE_PTR_RET #undef SET_RELOC_TYPE_RET #undef SET_INFO_FIELD_RET #undef FIND_MATCHING_SECTION_RET #undef ONLY_FOR_DEBUG_OR_VALIDATION_RET } /* * Validate the relocation information we've gathered. */ Elf_Word uShTypeArch = SHT_RELA; /** @todo generalize architecture specific stuff using its own code template header. */ switch (pModElf->Core.enmArch) { case RTLDRARCH_AMD64: break; case RTLDRARCH_X86_32: uShTypeArch = SHT_REL; break; default: AssertFailedBreak(/** @todo page size for got.plt hacks */); } if (pModElf->DynInfo.uRelocType != 0) { const char * const pszModifier = pModElf->DynInfo.uRelocType == DT_RELA ? "A" : ""; if (pModElf->DynInfo.uPtrRelocs == ~(Elf_Addr)0) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Missing DT_REL%s", pszLogName, pszModifier); if (pModElf->DynInfo.cbRelocs == 0) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Missing DT_REL%sSZ", pszLogName, pszModifier); if (pModElf->DynInfo.cbRelocEntry == 0) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Missing DT_REL%sENT", pszLogName, pszModifier); Elf_Shdr const *pShdrRelocs = &paShdrs[pModElf->DynInfo.idxShRelocs]; Elf_Word const uShType = pModElf->DynInfo.uJmpRelocType == DT_RELA ? SHT_RELA : SHT_REL; if (pShdrRelocs->sh_type != uShType) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT_REL%s* does not match section type: %u vs %u", pszLogName, pszModifier, pShdrRelocs->sh_type, uShType); if (pShdrRelocs->sh_size != pModElf->DynInfo.cbRelocs) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT_REL%sSZ does not match section size: %u vs %u", pszLogName, pszModifier, pShdrRelocs->sh_size, pModElf->DynInfo.cbRelocs); if (uShType != uShTypeArch) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT_REL%s* does not match architecture: %u, arch wants %u", pszLogName, pszModifier, uShType, uShTypeArch); } if ( pModElf->DynInfo.uPtrJmpRelocs != ~(Elf_Addr)0 || pModElf->DynInfo.cbJmpRelocs != 0 || pModElf->DynInfo.uJmpRelocType != 0) { if (pModElf->DynInfo.uPtrJmpRelocs == ~(Elf_Addr)0) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Missing DT_JMPREL", pszLogName); if (pModElf->DynInfo.cbJmpRelocs == 0) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Missing DT_PLTRELSZ", pszLogName); if (pModElf->DynInfo.uJmpRelocType == 0) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: Missing DT_PLTREL", pszLogName); Elf_Shdr const *pShdrRelocs = &paShdrs[pModElf->DynInfo.idxShJmpRelocs]; Elf_Word const uShType = pModElf->DynInfo.uJmpRelocType == DT_RELA ? SHT_RELA : SHT_REL; if (pShdrRelocs->sh_type != uShType) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT_PLTREL does not match section type: %u vs %u", pszLogName, pShdrRelocs->sh_type, uShType); if (pShdrRelocs->sh_size != pModElf->DynInfo.cbJmpRelocs) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT_PLTRELSZ does not match section size: %u vs %u", pszLogName, pShdrRelocs->sh_size, pModElf->DynInfo.cbJmpRelocs); if (uShType != uShTypeArch) return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: DT_PLTREL does not match architecture: %u, arch wants %u", pszLogName, uShType, uShTypeArch); } /* * Check that there aren't any other relocations hiding in the section table. */ for (uint32_t i = 1; i < pModElf->Ehdr.e_shnum; i++) if ( (paShdrs[i].sh_type == SHT_REL || paShdrs[i].sh_type == SHT_RELA) && pModElf->paShdrExtras[i].uDtTag != DT_REL && pModElf->paShdrExtras[i].uDtTag != DT_RELA && pModElf->paShdrExtras[i].uDtTag != DT_JMPREL) { char szSecHdrNm[80]; return RTERRINFO_LOG_SET_F(pErrInfo, VERR_BAD_EXE_FORMAT, "%s: section header #%u (%s type=" FMT_ELF_WORD " size=" FMT_ELF_XWORD ") contains relocations not referenced by the dynamic section", pszLogName, i, RTLDRELF_NAME(GetSHdrName)(pModElf, paShdrs[i].sh_name, szSecHdrNm, sizeof(szSecHdrNm)), paShdrs[i].sh_type, paShdrs[i].sh_size); } return VINF_SUCCESS; } /** * Opens an ELF image, fixed bitness. * * @returns iprt status code. * @param pReader The loader reader instance which will provide the raw image bits. * @param fFlags Reserved, MBZ. * @param enmArch Architecture specifier. * @param phLdrMod Where to store the handle. * @param pErrInfo Where to return extended error info. Optional. */ static int RTLDRELF_NAME(Open)(PRTLDRREADER pReader, uint32_t fFlags, RTLDRARCH enmArch, PRTLDRMOD phLdrMod, PRTERRINFO pErrInfo) { const char *pszLogName = pReader->pfnLogName(pReader); uint64_t cbRawImage = pReader->pfnSize(pReader); RT_NOREF_PV(fFlags); /* * Create the loader module instance. */ PRTLDRMODELF pModElf = (PRTLDRMODELF)RTMemAllocZ(sizeof(*pModElf)); if (!pModElf) return VERR_NO_MEMORY; pModElf->Core.u32Magic = RTLDRMOD_MAGIC; pModElf->Core.eState = LDR_STATE_INVALID; pModElf->Core.pReader = pReader; pModElf->Core.enmFormat = RTLDRFMT_ELF; pModElf->Core.enmType = RTLDRTYPE_OBJECT; pModElf->Core.enmEndian = RTLDRENDIAN_LITTLE; #if ELF_MODE == 32 pModElf->Core.enmArch = RTLDRARCH_X86_32; #else pModElf->Core.enmArch = RTLDRARCH_AMD64; #endif //pModElf->pvBits = NULL; //pModElf->Ehdr = {0}; //pModElf->paShdrs = NULL; //pModElf->Rel.paSyms = NULL; pModElf->Rel.iSymSh = ~0U; //pModElf->Rel.cSyms = 0; pModElf->Rel.iStrSh = ~0U; //pModElf->Rel.cbStr = 0; //pModElf->Rel.pStr = NULL; //pModElf->Dyn.paSyms = NULL; pModElf->Dyn.iSymSh = ~0U; //pModElf->Dyn.cSyms = 0; pModElf->Dyn.iStrSh = ~0U; //pModElf->Dyn.cbStr = 0; //pModElf->Dyn.pStr = NULL; pModElf->iFirstSect = 1; //pModElf->fShdrInOrder = false; //pModElf->cbImage = 0; pModElf->LinkAddress = ~(Elf_Addr)0; //pModElf->cbShStr = 0; //pModElf->pShStr = NULL; //pModElf->iShEhFrame = 0; //pModElf->iShEhFrameHdr= 0; pModElf->iShDynamic = ~0U; //pModElf->cDynamic = 0; //pModElf->paDynamic = NULL; //pModElf->paPhdrs = NULL; pModElf->DynInfo.uPtrRelocs = ~(Elf_Addr)0; //pModElf->DynInfo.cbRelocs = 0; //pModElf->DynInfo.cbRelocEntry = 0; //pModElf->DynInfo.uRelocType = 0; //pModElf->DynInfo.idxShRelocs = 0; pModElf->DynInfo.uPtrJmpRelocs = ~(Elf_Addr)0; //pModElf->DynInfo.cbJmpRelocs = 0; //pModElf->DynInfo.uJmpRelocType = 0; //pModElf->DynInfo.idxShJmpRelocs = 0; /* * Read and validate the ELF header and match up the CPU architecture. */ int rc = pReader->pfnRead(pReader, &pModElf->Ehdr, sizeof(pModElf->Ehdr), 0); if (RT_SUCCESS(rc)) { RTLDRARCH enmArchImage = RTLDRARCH_INVALID; /* shut up gcc */ rc = RTLDRELF_NAME(ValidateElfHeader)(&pModElf->Ehdr, cbRawImage, pszLogName, &enmArchImage, pErrInfo); if (RT_SUCCESS(rc)) { if ( enmArch != RTLDRARCH_WHATEVER && enmArch != enmArchImage) rc = VERR_LDR_ARCH_MISMATCH; } } if (RT_SUCCESS(rc)) { /* * Read the section headers, keeping a prestine copy for the module * introspection methods. */ size_t const cbShdrs = pModElf->Ehdr.e_shnum * sizeof(Elf_Shdr); Elf_Shdr *paShdrs = (Elf_Shdr *)RTMemAlloc(cbShdrs * 2 + sizeof(RTLDRMODELFSHX) * pModElf->Ehdr.e_shnum); if (paShdrs) { pModElf->paShdrs = paShdrs; rc = pReader->pfnRead(pReader, paShdrs, cbShdrs, pModElf->Ehdr.e_shoff); if (RT_SUCCESS(rc)) { memcpy(&paShdrs[pModElf->Ehdr.e_shnum], paShdrs, cbShdrs); pModElf->paOrgShdrs = &paShdrs[pModElf->Ehdr.e_shnum]; pModElf->paShdrExtras = (PRTLDRMODELFSHX)&pModElf->paOrgShdrs[pModElf->Ehdr.e_shnum]; memset(pModElf->paShdrExtras, 0xff, sizeof(RTLDRMODELFSHX) * pModElf->Ehdr.e_shnum); pModElf->cbShStr = paShdrs[pModElf->Ehdr.e_shstrndx].sh_size; /* * Validate the section headers and find relevant sections. */ rc = RTLDRELF_NAME(ValidateAndProcessSectionHeaders)(pModElf, paShdrs, cbRawImage, pszLogName, pErrInfo); /* * Read validate and process program headers if ET_DYN or ET_EXEC. */ if (RT_SUCCESS(rc) && (pModElf->Ehdr.e_type == ET_DYN || pModElf->Ehdr.e_type == ET_EXEC)) rc = RTLDRELF_NAME(ValidateAndProcessDynamicInfo)(pModElf, cbRawImage, fFlags, pszLogName, pErrInfo); /* * Massage the section headers. */ if (RT_SUCCESS(rc)) { if (pModElf->Ehdr.e_type == ET_REL) { /* Do allocations and figure the image size: */ pModElf->LinkAddress = 0; for (unsigned i = 1; i < pModElf->Ehdr.e_shnum; i++) if (paShdrs[i].sh_flags & SHF_ALLOC) { paShdrs[i].sh_addr = paShdrs[i].sh_addralign ? RT_ALIGN_T(pModElf->cbImage, paShdrs[i].sh_addralign, Elf_Addr) : (Elf_Addr)pModElf->cbImage; Elf_Addr EndAddr = paShdrs[i].sh_addr + paShdrs[i].sh_size; if (pModElf->cbImage < EndAddr) { pModElf->cbImage = (size_t)EndAddr; AssertMsgBreakStmt(pModElf->cbImage == EndAddr, (FMT_ELF_ADDR "\n", EndAddr), rc = VERR_IMAGE_TOO_BIG); } Log2(("RTLdrElf: %s: Assigned " FMT_ELF_ADDR " to section #%d\n", pszLogName, paShdrs[i].sh_addr, i)); } } else { /* Convert sh_addr to RVA: */ Assert(pModElf->LinkAddress != ~(Elf_Addr)0); for (unsigned i = 0 /*!*/; i < pModElf->Ehdr.e_shnum; i++) if (paShdrs[i].sh_flags & SHF_ALLOC) paShdrs[i].sh_addr -= pModElf->LinkAddress; } } /* * Check if the sections are in order by address, as that will simplify * enumeration and address translation. */ pModElf->fShdrInOrder = true; Elf_Addr uEndAddr = 0; for (unsigned i = pModElf->iFirstSect; i < pModElf->Ehdr.e_shnum; i++) if (paShdrs[i].sh_flags & SHF_ALLOC) { if (uEndAddr <= paShdrs[i].sh_addr) uEndAddr = paShdrs[i].sh_addr + paShdrs[i].sh_size; else { pModElf->fShdrInOrder = false; break; } } Log2(("RTLdrElf: iSymSh=%u cSyms=%u iStrSh=%u cbStr=%u rc=%Rrc cbImage=%#zx LinkAddress=" FMT_ELF_ADDR " fShdrInOrder=%RTbool\n", pModElf->Rel.iSymSh, pModElf->Rel.cSyms, pModElf->Rel.iStrSh, pModElf->Rel.cbStr, rc, pModElf->cbImage, pModElf->LinkAddress, pModElf->fShdrInOrder)); if (RT_SUCCESS(rc)) { pModElf->Core.pOps = &RTLDRELF_MID(s_rtldrElf,Ops); pModElf->Core.eState = LDR_STATE_OPENED; *phLdrMod = &pModElf->Core; LogFlow(("%s: %s: returns VINF_SUCCESS *phLdrMod=%p\n", __FUNCTION__, pszLogName, *phLdrMod)); return VINF_SUCCESS; } } RTMemFree(paShdrs); } else rc = VERR_NO_MEMORY; } RTMemFree(pModElf); LogFlow(("%s: returns %Rrc\n", __FUNCTION__, rc)); return rc; } /******************************************************************************* * Cleanup Constants And Macros * *******************************************************************************/ #undef RTLDRELF_NAME #undef RTLDRELF_SUFF #undef RTLDRELF_MID #undef FMT_ELF_ADDR #undef FMT_ELF_ADDR7 #undef FMT_ELF_HALF #undef FMT_ELF_SHALF #undef FMT_ELF_OFF #undef FMT_ELF_SIZE #undef FMT_ELF_SWORD #undef FMT_ELF_WORD #undef FMT_ELF_XWORD #undef FMT_ELF_SXWORD #undef Elf_Ehdr #undef Elf_Phdr #undef Elf_Shdr #undef Elf_Sym #undef Elf_Rel #undef Elf_Rela #undef Elf_Reloc #undef Elf_Nhdr #undef Elf_Dyn #undef Elf_Addr #undef Elf_Half #undef Elf_Off #undef Elf_Size #undef Elf_Sword #undef Elf_Word #undef Elf_Xword #undef Elf_Sxword #undef RTLDRMODELF #undef PRTLDRMODELF #undef ELF_R_SYM #undef ELF_R_TYPE #undef ELF_R_INFO #undef ELF_ST_BIND