Upstream-Status: Backport CVE-2014-8502 supporting patch. [YOCTO #7084] Signed-off-by: Armin Kuster From bf67003b4567600ed3022a439207ac8f26454f91 Mon Sep 17 00:00:00 2001 From: Nick Clifton Date: Mon, 27 Oct 2014 18:05:37 +0000 Subject: [PATCH] This fixes more seg-faults in tools like "strings" and "objdump" when presented with corrupt binaries. PR binutils/17512 * elf.c (bfd_section_from_shdr): Detect and warn about ELF binaries with a group of sections linked by the string table indicies. * peXXigen.c (pe_print_edata): Detect out of range rvas and entry counts for the Export Address table, Name Pointer table and Ordinal table. --- bfd/ChangeLog | 5 ++ bfd/elf.c | 194 ++++++++++++++++++++++++++++++++++++++------------------- bfd/peXXigen.c | 18 +++++- 3 files changed, 150 insertions(+), 67 deletions(-) Index: binutils-2.24/bfd/elf.c =================================================================== --- binutils-2.24.orig/bfd/elf.c +++ binutils-2.24/bfd/elf.c @@ -1574,38 +1574,67 @@ bfd_section_from_shdr (bfd *abfd, unsign Elf_Internal_Ehdr *ehdr; const struct elf_backend_data *bed; const char *name; + bfd_boolean ret = TRUE; + static bfd_boolean * sections_being_created = NULL; + static unsigned int nesting = 0; if (shindex >= elf_numsections (abfd)) return FALSE; + if (++ nesting > 3) + { + /* PR17512: A corrupt ELF binary might contain a recursive group of + sections, each the string indicies pointing to the next in the + loop. Detect this here, by refusing to load a section that we are + already in the process of loading. We only trigger this test if + we have nested at least three sections deep as normal ELF binaries + can expect to recurse at least once. */ + + if (sections_being_created == NULL) + { + /* FIXME: It would be more efficient to attach this array to the bfd somehow. */ + sections_being_created = (bfd_boolean *) + bfd_zalloc (abfd, elf_numsections (abfd) * sizeof (bfd_boolean)); + } + if (sections_being_created [shindex]) + { + (*_bfd_error_handler) + (_("%B: warning: loop in section dependencies detected"), abfd); + return FALSE; + } + sections_being_created [shindex] = TRUE; + } + hdr = elf_elfsections (abfd)[shindex]; ehdr = elf_elfheader (abfd); name = bfd_elf_string_from_elf_section (abfd, ehdr->e_shstrndx, hdr->sh_name); if (name == NULL) - return FALSE; + goto fail; bed = get_elf_backend_data (abfd); switch (hdr->sh_type) { case SHT_NULL: /* Inactive section. Throw it away. */ - return TRUE; + goto success; - case SHT_PROGBITS: /* Normal section with contents. */ - case SHT_NOBITS: /* .bss section. */ - case SHT_HASH: /* .hash section. */ - case SHT_NOTE: /* .note section. */ + case SHT_PROGBITS: /* Normal section with contents. */ + case SHT_NOBITS: /* .bss section. */ + case SHT_HASH: /* .hash section. */ + case SHT_NOTE: /* .note section. */ case SHT_INIT_ARRAY: /* .init_array section. */ case SHT_FINI_ARRAY: /* .fini_array section. */ case SHT_PREINIT_ARRAY: /* .preinit_array section. */ case SHT_GNU_LIBLIST: /* .gnu.liblist section. */ case SHT_GNU_HASH: /* .gnu.hash section. */ - return _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + ret = _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + goto success; case SHT_DYNAMIC: /* Dynamic linking information. */ if (! _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex)) - return FALSE; + goto fail; + if (hdr->sh_link > elf_numsections (abfd)) { /* PR 10478: Accept Solaris binaries with a sh_link @@ -1619,11 +1648,11 @@ bfd_section_from_shdr (bfd *abfd, unsign break; /* Otherwise fall through. */ default: - return FALSE; + goto fail; } } else if (elf_elfsections (abfd)[hdr->sh_link] == NULL) - return FALSE; + goto fail; else if (elf_elfsections (abfd)[hdr->sh_link]->sh_type != SHT_STRTAB) { Elf_Internal_Shdr *dynsymhdr; @@ -1652,24 +1681,26 @@ bfd_section_from_shdr (bfd *abfd, unsign } } } - break; + goto success; - case SHT_SYMTAB: /* A symbol table */ + case SHT_SYMTAB: /* A symbol table. */ if (elf_onesymtab (abfd) == shindex) - return TRUE; + goto success; if (hdr->sh_entsize != bed->s->sizeof_sym) - return FALSE; + goto fail; + if (hdr->sh_info * hdr->sh_entsize > hdr->sh_size) { if (hdr->sh_size != 0) - return FALSE; + goto fail; /* Some assemblers erroneously set sh_info to one with a zero sh_size. ld sees this as a global symbol count of (unsigned) -1. Fix it here. */ hdr->sh_info = 0; - return TRUE; + goto success; } + BFD_ASSERT (elf_onesymtab (abfd) == 0); elf_onesymtab (abfd) = shindex; elf_tdata (abfd)->symtab_hdr = *hdr; @@ -1686,7 +1717,7 @@ bfd_section_from_shdr (bfd *abfd, unsign && (abfd->flags & DYNAMIC) != 0 && ! _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex)) - return FALSE; + goto fail; /* Go looking for SHT_SYMTAB_SHNDX too, since if there is one we can't read symbols without that section loaded as well. It @@ -1712,26 +1743,29 @@ bfd_section_from_shdr (bfd *abfd, unsign break; } if (i != shindex) - return bfd_section_from_shdr (abfd, i); + ret = bfd_section_from_shdr (abfd, i); } - return TRUE; + goto success; - case SHT_DYNSYM: /* A dynamic symbol table */ + case SHT_DYNSYM: /* A dynamic symbol table. */ if (elf_dynsymtab (abfd) == shindex) - return TRUE; + goto success; if (hdr->sh_entsize != bed->s->sizeof_sym) - return FALSE; + goto fail; + if (hdr->sh_info * hdr->sh_entsize > hdr->sh_size) { if (hdr->sh_size != 0) - return FALSE; + goto fail; + /* Some linkers erroneously set sh_info to one with a zero sh_size. ld sees this as a global symbol count of (unsigned) -1. Fix it here. */ hdr->sh_info = 0; - return TRUE; + goto success; } + BFD_ASSERT (elf_dynsymtab (abfd) == 0); elf_dynsymtab (abfd) = shindex; elf_tdata (abfd)->dynsymtab_hdr = *hdr; @@ -1740,34 +1774,38 @@ bfd_section_from_shdr (bfd *abfd, unsign /* Besides being a symbol table, we also treat this as a regular section, so that objcopy can handle it. */ - return _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + ret = _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + goto success; - case SHT_SYMTAB_SHNDX: /* Symbol section indices when >64k sections */ + case SHT_SYMTAB_SHNDX: /* Symbol section indices when >64k sections. */ if (elf_symtab_shndx (abfd) == shindex) - return TRUE; + goto success; BFD_ASSERT (elf_symtab_shndx (abfd) == 0); elf_symtab_shndx (abfd) = shindex; elf_tdata (abfd)->symtab_shndx_hdr = *hdr; elf_elfsections (abfd)[shindex] = &elf_tdata (abfd)->symtab_shndx_hdr; - return TRUE; + goto success; - case SHT_STRTAB: /* A string table */ + case SHT_STRTAB: /* A string table. */ if (hdr->bfd_section != NULL) - return TRUE; + goto success; + if (ehdr->e_shstrndx == shindex) { elf_tdata (abfd)->shstrtab_hdr = *hdr; elf_elfsections (abfd)[shindex] = &elf_tdata (abfd)->shstrtab_hdr; - return TRUE; + goto success; } + if (elf_elfsections (abfd)[elf_onesymtab (abfd)]->sh_link == shindex) { symtab_strtab: elf_tdata (abfd)->strtab_hdr = *hdr; elf_elfsections (abfd)[shindex] = &elf_tdata (abfd)->strtab_hdr; - return TRUE; + goto success; } + if (elf_elfsections (abfd)[elf_dynsymtab (abfd)]->sh_link == shindex) { dynsymtab_strtab: @@ -1776,8 +1814,9 @@ bfd_section_from_shdr (bfd *abfd, unsign elf_elfsections (abfd)[shindex] = hdr; /* We also treat this as a regular section, so that objcopy can handle it. */ - return _bfd_elf_make_section_from_shdr (abfd, hdr, name, - shindex); + ret = _bfd_elf_make_section_from_shdr (abfd, hdr, name, + shindex); + goto success; } /* If the string table isn't one of the above, then treat it as a @@ -1795,9 +1834,9 @@ bfd_section_from_shdr (bfd *abfd, unsign { /* Prevent endless recursion on broken objects. */ if (i == shindex) - return FALSE; + goto fail; if (! bfd_section_from_shdr (abfd, i)) - return FALSE; + goto fail; if (elf_onesymtab (abfd) == i) goto symtab_strtab; if (elf_dynsymtab (abfd) == i) @@ -1805,7 +1844,8 @@ bfd_section_from_shdr (bfd *abfd, unsign } } } - return _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + ret = _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + goto success; case SHT_REL: case SHT_RELA: @@ -1820,7 +1860,7 @@ bfd_section_from_shdr (bfd *abfd, unsign if (hdr->sh_entsize != (bfd_size_type) (hdr->sh_type == SHT_REL ? bed->s->sizeof_rel : bed->s->sizeof_rela)) - return FALSE; + goto fail; /* Check for a bogus link to avoid crashing. */ if (hdr->sh_link >= num_sec) @@ -1828,8 +1868,9 @@ bfd_section_from_shdr (bfd *abfd, unsign ((*_bfd_error_handler) (_("%B: invalid link %lu for reloc section %s (index %u)"), abfd, hdr->sh_link, name, shindex)); - return _bfd_elf_make_section_from_shdr (abfd, hdr, name, - shindex); + ret = _bfd_elf_make_section_from_shdr (abfd, hdr, name, + shindex); + goto success; } /* For some incomprehensible reason Oracle distributes @@ -1870,7 +1911,7 @@ bfd_section_from_shdr (bfd *abfd, unsign if ((elf_elfsections (abfd)[hdr->sh_link]->sh_type == SHT_SYMTAB || elf_elfsections (abfd)[hdr->sh_link]->sh_type == SHT_DYNSYM) && ! bfd_section_from_shdr (abfd, hdr->sh_link)) - return FALSE; + goto fail; /* If this reloc section does not use the main symbol table we don't treat it as a reloc section. BFD can't adequately @@ -1885,14 +1926,18 @@ bfd_section_from_shdr (bfd *abfd, unsign || hdr->sh_info >= num_sec || elf_elfsections (abfd)[hdr->sh_info]->sh_type == SHT_REL || elf_elfsections (abfd)[hdr->sh_info]->sh_type == SHT_RELA) - return _bfd_elf_make_section_from_shdr (abfd, hdr, name, - shindex); + { + ret = _bfd_elf_make_section_from_shdr (abfd, hdr, name, + shindex); + goto success; + } if (! bfd_section_from_shdr (abfd, hdr->sh_info)) - return FALSE; + goto fail; + target_sect = bfd_section_from_elf_index (abfd, hdr->sh_info); if (target_sect == NULL) - return FALSE; + goto fail; esdt = elf_section_data (target_sect); if (hdr->sh_type == SHT_RELA) @@ -1904,7 +1949,7 @@ bfd_section_from_shdr (bfd *abfd, unsign amt = sizeof (*hdr2); hdr2 = (Elf_Internal_Shdr *) bfd_alloc (abfd, amt); if (hdr2 == NULL) - return FALSE; + goto fail; *hdr2 = *hdr; *p_hdr = hdr2; elf_elfsections (abfd)[shindex] = hdr2; @@ -1920,34 +1965,40 @@ bfd_section_from_shdr (bfd *abfd, unsign target_sect->use_rela_p = 1; } abfd->flags |= HAS_RELOC; - return TRUE; + goto success; } case SHT_GNU_verdef: elf_dynverdef (abfd) = shindex; elf_tdata (abfd)->dynverdef_hdr = *hdr; - return _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + ret = _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + goto success; case SHT_GNU_versym: if (hdr->sh_entsize != sizeof (Elf_External_Versym)) - return FALSE; + goto fail; + elf_dynversym (abfd) = shindex; elf_tdata (abfd)->dynversym_hdr = *hdr; - return _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + ret = _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + goto success; case SHT_GNU_verneed: elf_dynverref (abfd) = shindex; elf_tdata (abfd)->dynverref_hdr = *hdr; - return _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + ret = _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + goto success; case SHT_SHLIB: - return TRUE; + goto success; case SHT_GROUP: if (! IS_VALID_GROUP_SECTION_HEADER (hdr, GRP_ENTRY_SIZE)) - return FALSE; + goto fail; + if (!_bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex)) - return FALSE; + goto fail; + if (hdr->contents != NULL) { Elf_Internal_Group *idx = (Elf_Internal_Group *) hdr->contents; @@ -1973,7 +2024,7 @@ bfd_section_from_shdr (bfd *abfd, unsign } } } - break; + goto success; default: /* Possibly an attributes section. */ @@ -1981,14 +2032,14 @@ bfd_section_from_shdr (bfd *abfd, unsign || hdr->sh_type == bed->obj_attrs_section_type) { if (! _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex)) - return FALSE; + goto fail; _bfd_elf_parse_attributes (abfd, hdr); - return TRUE; + goto success; } /* Check for any processor-specific section types. */ if (bed->elf_backend_section_from_shdr (abfd, hdr, name, shindex)) - return TRUE; + goto success; if (hdr->sh_type >= SHT_LOUSER && hdr->sh_type <= SHT_HIUSER) { @@ -2000,9 +2051,12 @@ bfd_section_from_shdr (bfd *abfd, unsign "specific section `%s' [0x%8x]"), abfd, name, hdr->sh_type); else - /* Allow sections reserved for applications. */ - return _bfd_elf_make_section_from_shdr (abfd, hdr, name, - shindex); + { + /* Allow sections reserved for applications. */ + ret = _bfd_elf_make_section_from_shdr (abfd, hdr, name, + shindex); + goto success; + } } else if (hdr->sh_type >= SHT_LOPROC && hdr->sh_type <= SHT_HIPROC) @@ -2023,8 +2077,11 @@ bfd_section_from_shdr (bfd *abfd, unsign "`%s' [0x%8x]"), abfd, name, hdr->sh_type); else - /* Otherwise it should be processed. */ - return _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + { + /* Otherwise it should be processed. */ + ret = _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex); + goto success; + } } else /* FIXME: We should handle this section. */ @@ -2032,10 +2089,17 @@ bfd_section_from_shdr (bfd *abfd, unsign (_("%B: don't know how to handle section `%s' [0x%8x]"), abfd, name, hdr->sh_type); - return FALSE; + goto fail; } - return TRUE; + fail: + ret = FALSE; + success: + if (sections_being_created) + sections_being_created [shindex] = FALSE; + if (-- nesting == 0) + sections_being_created = NULL; + return ret; } /* Return the local symbol specified by ABFD, R_SYMNDX. */ Index: binutils-2.24/bfd/peXXigen.c =================================================================== --- binutils-2.24.orig/bfd/peXXigen.c +++ binutils-2.24/bfd/peXXigen.c @@ -1528,7 +1528,12 @@ pe_print_edata (bfd * abfd, void * vfile _("\nExport Address Table -- Ordinal Base %ld\n"), edt.base); - for (i = 0; i < edt.num_functions; ++i) + /* PR 17512: Handle corrupt PE binaries. */ + if (edt.eat_addr + (edt.num_functions * 4) - adj >= datasize) + fprintf (file, _("\tInvalid Export Address Table rva (0x%lx) or entry count (0x%lx)\n"), + (long) edt.eat_addr, + (long) edt.num_functions); + else for (i = 0; i < edt.num_functions; ++i) { bfd_vma eat_member = bfd_get_32 (abfd, data + edt.eat_addr + (i * 4) - adj); @@ -1564,7 +1569,16 @@ pe_print_edata (bfd * abfd, void * vfile fprintf (file, _("\n[Ordinal/Name Pointer] Table\n")); - for (i = 0; i < edt.num_names; ++i) + /* PR 17512: Handle corrupt PE binaries. */ + if (edt.npt_addr + (edt.num_names * 4) - adj >= datasize) + fprintf (file, _("\tInvalid Name Pointer Table rva (0x%lx) or entry count (0x%lx)\n"), + (long) edt.npt_addr, + (long) edt.num_names); + else if (edt.ot_addr + (edt.num_names * 2) - adj >= datasize) + fprintf (file, _("\tInvalid Ordinal Table rva (0x%lx) or entry count (0x%lx)\n"), + (long) edt.ot_addr, + (long) edt.num_names); + else for (i = 0; i < edt.num_names; ++i) { bfd_vma name_ptr = bfd_get_32 (abfd, data + Index: binutils-2.24/bfd/ChangeLog =================================================================== --- binutils-2.24.orig/bfd/ChangeLog +++ binutils-2.24/bfd/ChangeLog @@ -1,8 +1,13 @@ 2014-10-27 Nick Clifton PR binutils/17512 + * elf.c (bfd_section_from_shdr): Detect and warn about ELF + binaries with a group of sections linked by the string table + indicies. * peXXigen.c (_bfd_XXi_swap_aouthdr_in): Handle corrupt binaries with an invalid value for NumberOfRvaAndSizes. + (pe_print_edata): Detect out of range rvas and entry counts for + the Export Address table, Name Pointer table and Ordinal table. PR binutils/17510 * elf.c (setup_group): Improve handling of corrupt group