diff --git a/src/patchelf.cc b/src/patchelf.cc index 136098fb..91abc6ed 100644 --- a/src/patchelf.cc +++ b/src/patchelf.cc @@ -53,8 +53,8 @@ off_t fileSize, maxSize; unsigned char * contents = 0; -#define ElfFileParams class Elf_Ehdr, class Elf_Phdr, class Elf_Shdr, class Elf_Addr, class Elf_Off, class Elf_Dyn, class Elf_Sym -#define ElfFileParamNames Elf_Ehdr, Elf_Phdr, Elf_Shdr, Elf_Addr, Elf_Off, Elf_Dyn, Elf_Sym +#define ElfFileParams class Elf_Ehdr, class Elf_Phdr, class Elf_Shdr, class Elf_Addr, class Elf_Off, class Elf_Dyn, class Elf_Sym, class Elf_Verneed +#define ElfFileParamNames Elf_Ehdr, Elf_Phdr, Elf_Shdr, Elf_Addr, Elf_Off, Elf_Dyn, Elf_Sym, Elf_Verneed static unsigned int getPageSize(){ @@ -1260,6 +1260,8 @@ void ElfFile::replaceNeeded(map& libs) Elf_Dyn * dyn = (Elf_Dyn *) (contents + rdi(shdrDynamic.sh_offset)); + unsigned int verNeedNum = 0; + unsigned int dynStrAddedBytes = 0; for ( ; rdi(dyn->d_tag) != DT_NULL; dyn++) { @@ -1272,13 +1274,13 @@ void ElfFile::replaceNeeded(map& libs) // technically, the string referred by d_val could be used otherwise, too (although unlikely) // we'll therefore add a new string - debug("resizing .dynstr ..."); + debug("resizing .dynstr ...\n"); string & newDynStr = replaceSection(".dynstr", rdi(shdrDynStr.sh_size) + replacement.size() + 1 + dynStrAddedBytes); setSubstr(newDynStr, rdi(shdrDynStr.sh_size) + dynStrAddedBytes, replacement + '\0'); - dyn->d_un.d_val = shdrDynStr.sh_size + dynStrAddedBytes; + wri(dyn->d_un.d_val, rdi(shdrDynStr.sh_size) + dynStrAddedBytes); dynStrAddedBytes += replacement.size() + 1; @@ -1287,6 +1289,57 @@ void ElfFile::replaceNeeded(map& libs) debug("keeping DT_NEEDED entry `%s'\n", name); } } + if (rdi(dyn->d_tag) == DT_VERNEEDNUM) { + verNeedNum = rdi(dyn->d_un.d_val); + } + } + + // If a replaced library uses symbol versions, then there will also be + // references to it in the "version needed" table, and these also need to + // be replaced. + + if (verNeedNum) { + Elf_Shdr & shdrVersionR = findSection(".gnu.version_r"); + // The filename strings in the .gnu.version_r are different from the + // ones in .dynamic: instead of being in .dynstr, they're in some + // arbitrary section and we have to look in ->sh_link to figure out + // which one. + Elf_Shdr & shdrVersionRStrings = shdrs[rdi(shdrVersionR.sh_link)]; + // this is where we find the actual filename strings + char * verStrTab = (char *) contents + rdi(shdrVersionRStrings.sh_offset); + // and we also need the name of the section containing the strings, so + // that we can pass it to replaceSection + string versionRStringsSName = getSectionName(shdrVersionRStrings); + + debug("found .gnu.version_r with %i entries, strings in %s\n", verNeedNum, versionRStringsSName.c_str()); + + unsigned int verStrAddedBytes = 0; + + Elf_Verneed * need = (Elf_Verneed *) (contents + rdi(shdrVersionR.sh_offset)); + while (verNeedNum > 0) { + char * file = verStrTab + rdi(need->vn_file); + if (libs.find(file) != libs.end()) { + const string & replacement = libs[file]; + + debug("replacing .gnu.version_r entry `%s' with `%s'\n", file, replacement.c_str()); + debug("resizing string section %s ...\n", versionRStringsSName.c_str()); + + string & newVerDynStr = replaceSection(versionRStringsSName, + rdi(shdrVersionRStrings.sh_size) + replacement.size() + 1 + verStrAddedBytes); + setSubstr(newVerDynStr, rdi(shdrVersionRStrings.sh_size) + verStrAddedBytes, replacement + '\0'); + + wri(need->vn_file, rdi(shdrVersionRStrings.sh_size) + verStrAddedBytes); + + verStrAddedBytes += replacement.size() + 1; + + changed = true; + } else { + debug("keeping .gnu.version_r entry `%s'\n", file); + } + // the Elf_Verneed structures form a linked list, so jump to next entry + need = (Elf_Verneed *) (contents + rdi(shdrVersionR.sh_offset) + rdi(need->vn_next)); + --verNeedNum; + } } } @@ -1474,13 +1527,13 @@ static void patchElf() if (contents[EI_CLASS] == ELFCLASS32 && contents[EI_VERSION] == EV_CURRENT) { - ElfFile elfFile; + ElfFile elfFile; patchElf2(elfFile); } else if (contents[EI_CLASS] == ELFCLASS64 && contents[EI_VERSION] == EV_CURRENT) { - ElfFile elfFile; + ElfFile elfFile; patchElf2(elfFile); } else {