X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=bfd%2Felf-eh-frame.c;h=e787ee9f1b4efcdee6848d9443aad7c4a088f639;hb=4ade44b727ee77adaa9c22719935d012e253a5e6;hp=832a99192deb6a0d172837a1804e116b32c0c3f2;hpb=12bd695738760b28c04dd34b3ff228247ec747c9;p=deliverable%2Fbinutils-gdb.git diff --git a/bfd/elf-eh-frame.c b/bfd/elf-eh-frame.c index 832a99192d..e787ee9f1b 100644 --- a/bfd/elf-eh-frame.c +++ b/bfd/elf-eh-frame.c @@ -1,6 +1,5 @@ /* .eh_frame section optimization. - Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, - 2012 Free Software Foundation, Inc. + Copyright (C) 2001-2016 Free Software Foundation, Inc. Written by Jakub Jelinek . This file is part of BFD, the Binary File Descriptor library. @@ -41,10 +40,12 @@ struct cie bfd_vma augmentation_size; union { struct elf_link_hash_entry *h; - bfd_vma val; + struct { + unsigned int bfd_id; + unsigned int index; + } sym; unsigned int reloc_index; } personality; - asection *output_sec; struct eh_cie_fde *cie_inf; unsigned char per_encoding; unsigned char lsda_encoding; @@ -230,11 +231,13 @@ cie_eq (const void *e1, const void *e2) && c1->augmentation_size == c2->augmentation_size && memcmp (&c1->personality, &c2->personality, sizeof (c1->personality)) == 0 - && c1->output_sec == c2->output_sec + && (c1->cie_inf->u.cie.u.sec->output_section + == c2->cie_inf->u.cie.u.sec->output_section) && c1->per_encoding == c2->per_encoding && c1->lsda_encoding == c2->lsda_encoding && c1->fde_encoding == c2->fde_encoding && c1->initial_insn_length == c2->initial_insn_length + && c1->initial_insn_length <= sizeof (c1->initial_instructions) && memcmp (c1->initial_instructions, c2->initial_instructions, c1->initial_insn_length) == 0) @@ -254,6 +257,7 @@ static hashval_t cie_compute_hash (struct cie *c) { hashval_t h = 0; + size_t len; h = iterative_hash_object (c->length, h); h = iterative_hash_object (c->version, h); h = iterative_hash (c->augmentation, strlen (c->augmentation) + 1, h); @@ -262,12 +266,15 @@ cie_compute_hash (struct cie *c) h = iterative_hash_object (c->ra_column, h); h = iterative_hash_object (c->augmentation_size, h); h = iterative_hash_object (c->personality, h); - h = iterative_hash_object (c->output_sec, h); + h = iterative_hash_object (c->cie_inf->u.cie.u.sec->output_section, h); h = iterative_hash_object (c->per_encoding, h); h = iterative_hash_object (c->lsda_encoding, h); h = iterative_hash_object (c->fde_encoding, h); h = iterative_hash_object (c->initial_insn_length, h); - h = iterative_hash (c->initial_instructions, c->initial_insn_length, h); + len = c->initial_insn_length; + if (len > sizeof (c->initial_instructions)) + len = sizeof (c->initial_instructions); + h = iterative_hash (c->initial_instructions, len, h); c->hash = h; return h; } @@ -445,16 +452,109 @@ make_pc_relative (unsigned char encoding, unsigned int ptr_size) return encoding | DW_EH_PE_pcrel; } -/* Called before calling _bfd_elf_parse_eh_frame on every input bfd's - .eh_frame section. */ +/* Examine each .eh_frame_entry section and discard those + those that are marked SEC_EXCLUDE. */ -void -_bfd_elf_begin_eh_frame_parsing (struct bfd_link_info *info) +static void +bfd_elf_discard_eh_frame_entry (struct eh_frame_hdr_info *hdr_info) +{ + unsigned int i; + for (i = 0; i < hdr_info->array_count; i++) + { + if (hdr_info->u.compact.entries[i]->flags & SEC_EXCLUDE) + { + unsigned int j; + for (j = i + 1; j < hdr_info->array_count; j++) + hdr_info->u.compact.entries[j-1] = hdr_info->u.compact.entries[j]; + + hdr_info->array_count--; + hdr_info->u.compact.entries[hdr_info->array_count] = NULL; + i--; + } + } +} + +/* Add a .eh_frame_entry section. */ + +static void +bfd_elf_record_eh_frame_entry (struct eh_frame_hdr_info *hdr_info, + asection *sec) { + if (hdr_info->array_count == hdr_info->u.compact.allocated_entries) + { + if (hdr_info->u.compact.allocated_entries == 0) + { + hdr_info->frame_hdr_is_compact = TRUE; + hdr_info->u.compact.allocated_entries = 2; + hdr_info->u.compact.entries = + bfd_malloc (hdr_info->u.compact.allocated_entries + * sizeof (hdr_info->u.compact.entries[0])); + } + else + { + hdr_info->u.compact.allocated_entries *= 2; + hdr_info->u.compact.entries = + bfd_realloc (hdr_info->u.compact.entries, + hdr_info->u.compact.allocated_entries + * sizeof (hdr_info->u.compact.entries[0])); + } + + BFD_ASSERT (hdr_info->u.compact.entries); + } + + hdr_info->u.compact.entries[hdr_info->array_count++] = sec; +} + +/* Parse a .eh_frame_entry section. Figure out which text section it + references. */ + +bfd_boolean +_bfd_elf_parse_eh_frame_entry (struct bfd_link_info *info, + asection *sec, struct elf_reloc_cookie *cookie) +{ + struct elf_link_hash_table *htab; struct eh_frame_hdr_info *hdr_info; + unsigned long r_symndx; + asection *text_sec; - hdr_info = &elf_hash_table (info)->eh_info; - hdr_info->merge_cies = !info->relocatable; + htab = elf_hash_table (info); + hdr_info = &htab->eh_info; + + if (sec->size == 0 + || sec->sec_info_type != SEC_INFO_TYPE_NONE) + { + return TRUE; + } + + if (sec->output_section && bfd_is_abs_section (sec->output_section)) + { + /* At least one of the sections is being discarded from the + link, so we should just ignore them. */ + return TRUE; + } + + if (cookie->rel == cookie->relend) + return FALSE; + + /* The first relocation is the function start. */ + r_symndx = cookie->rel->r_info >> cookie->r_sym_shift; + if (r_symndx == STN_UNDEF) + return FALSE; + + text_sec = _bfd_elf_section_for_symbol (cookie, r_symndx, FALSE); + + if (text_sec == NULL) + return FALSE; + + elf_section_eh_frame_entry (text_sec) = sec; + if (text_sec->output_section + && bfd_is_abs_section (text_sec->output_section)) + sec->flags |= SEC_EXCLUDE; + + sec->sec_info_type = SEC_INFO_TYPE_EH_FRAME_ENTRY; + elf_section_data (sec)->sec_info = text_sec; + bfd_elf_record_eh_frame_entry (hdr_info, sec); + return TRUE; } /* Try to parse .eh_frame section SEC, which belongs to ABFD. Store the @@ -487,8 +587,6 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, htab = elf_hash_table (info); hdr_info = &htab->eh_info; - if (hdr_info->parsed_eh_frames) - return; if (sec->size == 0 || sec->sec_info_type != SEC_INFO_TYPE_NONE) @@ -563,10 +661,13 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, /* FIXME: octets_per_byte. */ #define ENSURE_NO_RELOCS(buf) \ - REQUIRE (!(cookie->rel < cookie->relend \ - && (cookie->rel->r_offset \ - < (bfd_size_type) ((buf) - ehbuf)) \ - && cookie->rel->r_info != 0)) + while (cookie->rel < cookie->relend \ + && (cookie->rel->r_offset \ + < (bfd_size_type) ((buf) - ehbuf))) \ + { \ + REQUIRE (cookie->rel->r_info == 0); \ + cookie->rel++; \ + } /* FIXME: octets_per_byte. */ #define SKIP_RELOCS(buf) \ @@ -632,7 +733,6 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, cie->cie_inf = this_inf; cie->length = hdr_length; - cie->output_sec = sec->output_section; start = buf; REQUIRE (read_byte (&buf, end, &cie->version)); @@ -733,7 +833,7 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, /* For shared libraries, try to get rid of as many RELATIVE relocs as possible. */ - if (info->shared + if (bfd_link_pic (info) && (get_elf_backend_data (abfd) ->elf_backend_can_make_relative_eh_frame (abfd, info, sec))) @@ -762,19 +862,21 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, cie->fde_encoding = DW_EH_PE_absptr; initial_insn_length = end - buf; - if (initial_insn_length <= sizeof (cie->initial_instructions)) - { - cie->initial_insn_length = initial_insn_length; - memcpy (cie->initial_instructions, buf, initial_insn_length); - } + cie->initial_insn_length = initial_insn_length; + memcpy (cie->initial_instructions, buf, + initial_insn_length <= sizeof (cie->initial_instructions) + ? initial_insn_length : sizeof (cie->initial_instructions)); insns = buf; buf += initial_insn_length; ENSURE_NO_RELOCS (buf); - if (hdr_info->merge_cies) - this_inf->u.cie.u.full_cie = cie; - this_inf->u.cie.per_encoding_relative - = (cie->per_encoding & 0x70) == DW_EH_PE_pcrel; + if (!bfd_link_relocatable (info)) + { + /* Keep info for merging cies. */ + this_inf->u.cie.u.full_cie = cie; + this_inf->u.cie.per_encoding_relative + = (cie->per_encoding & 0x70) == DW_EH_PE_pcrel; + } } else { @@ -800,7 +902,8 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, REQUIRE (GET_RELOC (buf)); /* Chain together the FDEs for each section. */ - rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, cookie); + rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, + cookie, NULL); /* RSEC will be NULL if FDE was cleared out as it was belonging to a discarded SHT_GROUP. */ if (rsec) @@ -816,6 +919,16 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, length = get_DW_EH_PE_width (cie->fde_encoding, ptr_size); REQUIRE (skip_bytes (&buf, end, 2 * length)); + SKIP_RELOCS (buf - length); + if (!GET_RELOC (buf - length) + && read_value (abfd, buf - length, length, FALSE) == 0) + { + (*info->callbacks->minfo) + (_("discarding zero address range FDE in %B(%A).\n"), + abfd, sec); + this_inf->u.fde.cie_inf = NULL; + } + /* Skip the augmentation size, if present. */ if (cie->augmentation[0] == 'z') REQUIRE (read_uleb128 (&buf, end, &length)); @@ -905,8 +1018,9 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, elf_section_data (sec)->sec_info = sec_info; sec->sec_info_type = SEC_INFO_TYPE_EH_FRAME; - if (hdr_info->merge_cies) + if (!bfd_link_relocatable (info)) { + /* Keep info for merging cies. */ sec_info->cies = local_cies; local_cies = NULL; } @@ -916,7 +1030,7 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, (*info->callbacks->einfo) (_("%P: error in %B(%A); no .eh_frame_hdr table will be created.\n"), abfd, sec); - hdr_info->table = FALSE; + hdr_info->u.dwarf.table = FALSE; if (sec_info) free (sec_info); success: @@ -927,15 +1041,87 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, #undef REQUIRE } -/* Finish a pass over all .eh_frame sections. */ +/* Order eh_frame_hdr entries by the VMA of their text section. */ -void +static int +cmp_eh_frame_hdr (const void *a, const void *b) +{ + bfd_vma text_a; + bfd_vma text_b; + asection *sec; + + sec = *(asection *const *)a; + sec = (asection *) elf_section_data (sec)->sec_info; + text_a = sec->output_section->vma + sec->output_offset; + sec = *(asection *const *)b; + sec = (asection *) elf_section_data (sec)->sec_info; + text_b = sec->output_section->vma + sec->output_offset; + + if (text_a < text_b) + return -1; + return text_a > text_b; + +} + +/* Add space for a CANTUNWIND terminator to SEC if the text sections + referenced by it and NEXT are not contiguous, or NEXT is NULL. */ + +static void +add_eh_frame_hdr_terminator (asection *sec, + asection *next) +{ + bfd_vma end; + bfd_vma next_start; + asection *text_sec; + + if (next) + { + /* See if there is a gap (presumably a text section without unwind info) + between these two entries. */ + text_sec = (asection *) elf_section_data (sec)->sec_info; + end = text_sec->output_section->vma + text_sec->output_offset + + text_sec->size; + text_sec = (asection *) elf_section_data (next)->sec_info; + next_start = text_sec->output_section->vma + text_sec->output_offset; + if (end == next_start) + return; + } + + /* Add space for a CANTUNWIND terminator. */ + if (!sec->rawsize) + sec->rawsize = sec->size; + + bfd_set_section_size (sec->owner, sec, sec->size + 8); +} + +/* Finish a pass over all .eh_frame_entry sections. */ + +bfd_boolean _bfd_elf_end_eh_frame_parsing (struct bfd_link_info *info) { struct eh_frame_hdr_info *hdr_info; + unsigned int i; hdr_info = &elf_hash_table (info)->eh_info; - hdr_info->parsed_eh_frames = TRUE; + + if (info->eh_frame_hdr_type != COMPACT_EH_HDR + || hdr_info->array_count == 0) + return FALSE; + + bfd_elf_discard_eh_frame_entry (hdr_info); + + qsort (hdr_info->u.compact.entries, hdr_info->array_count, + sizeof (asection *), cmp_eh_frame_hdr); + + for (i = 0; i < hdr_info->array_count - 1; i++) + { + add_eh_frame_hdr_terminator (hdr_info->u.compact.entries[i], + hdr_info->u.compact.entries[i + 1]); + } + + /* Add a CANTUNWIND terminator after the last entry. */ + add_eh_frame_hdr_terminator (hdr_info->u.compact.entries[i], NULL); + return TRUE; } /* Mark all relocations against CIE or FDE ENT, which occurs in @@ -977,7 +1163,7 @@ _bfd_elf_gc_mark_fdes (struct bfd_link_info *info, asection *sec, /* At this stage, all cie_inf fields point to local CIEs, so we can use the same cookie to refer to them. */ cie = fde->u.fde.cie_inf; - if (!cie->u.cie.gc_mark) + if (cie != NULL && !cie->u.cie.gc_mark) { cie->u.cie.gc_mark = 1; if (!mark_entry (info, eh_frame, cie, gc_mark_hook, cookie)) @@ -1027,8 +1213,12 @@ find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec, { bfd_boolean per_binds_local; - /* Work out the address of personality routine, either as an absolute - value or as a symbol. */ + /* Work out the address of personality routine, or at least + enough info that we could calculate the address had we made a + final section layout. The symbol on the reloc is enough, + either the hash for a global, or (bfd id, index) pair for a + local. The assumption here is that no one uses addends on + the reloc. */ rel = cookie->rels + cie->personality.reloc_index; memset (&cie->personality, 0, sizeof (cie->personality)); #ifdef BFD64 @@ -1068,14 +1258,13 @@ find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec, return cie_inf; cie->local_personality = 1; - cie->personality.val = (sym->st_value - + sym_sec->output_offset - + sym_sec->output_section->vma); + cie->personality.sym.bfd_id = abfd->id; + cie->personality.sym.index = r_symndx; per_binds_local = TRUE; } if (per_binds_local - && info->shared + && bfd_link_pic (info) && (cie->per_encoding & 0x70) == DW_EH_PE_absptr && (get_elf_backend_data (abfd) ->elf_backend_can_make_relative_eh_frame (abfd, info, sec))) @@ -1086,15 +1275,15 @@ find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec, } /* See if we can merge this CIE with an earlier one. */ - cie->output_sec = sec->output_section; cie_compute_hash (cie); - if (hdr_info->cies == NULL) + if (hdr_info->u.dwarf.cies == NULL) { - hdr_info->cies = htab_try_create (1, cie_hash, cie_eq, free); - if (hdr_info->cies == NULL) + hdr_info->u.dwarf.cies = htab_try_create (1, cie_hash, cie_eq, free); + if (hdr_info->u.dwarf.cies == NULL) return cie_inf; } - loc = htab_find_slot_with_hash (hdr_info->cies, cie, cie->hash, INSERT); + loc = htab_find_slot_with_hash (hdr_info->u.dwarf.cies, cie, + cie->hash, INSERT); if (loc == NULL) return cie_inf; @@ -1153,7 +1342,7 @@ _bfd_elf_discard_section_eh_frame /* There should only be one zero terminator, on the last input file supplying .eh_frame (crtend.o). Remove any others. */ ent->removed = sec->map_head.s != NULL; - else if (!ent->cie) + else if (!ent->cie && ent->u.fde.cie_inf != NULL) { bfd_boolean keep; if ((sec->flags & SEC_LINKER_CREATED) != 0 && cookie->rels == NULL) @@ -1175,22 +1364,34 @@ _bfd_elf_discard_section_eh_frame } if (keep) { - if (info->shared + if (bfd_link_pic (info) && (((ent->fde_encoding & 0x70) == DW_EH_PE_absptr && ent->make_relative == 0) || (ent->fde_encoding & 0x70) == DW_EH_PE_aligned)) { + static int num_warnings_issued = 0; + /* If a shared library uses absolute pointers which we cannot turn into PC relative, don't create the binary search table, since it is affected by runtime relocations. */ - hdr_info->table = FALSE; - (*info->callbacks->einfo) - (_("%P: fde encoding in %B(%A) prevents .eh_frame_hdr" - " table being created.\n"), abfd, sec); + hdr_info->u.dwarf.table = FALSE; + if (num_warnings_issued < 10) + { + (*info->callbacks->einfo) + (_("%P: FDE encoding in %B(%A) prevents .eh_frame_hdr" + " table being created.\n"), abfd, sec); + num_warnings_issued ++; + } + else if (num_warnings_issued == 10) + { + (*info->callbacks->einfo) + (_("%P: Further warnings about FDE encoding preventing .eh_frame_hdr generation dropped.\n")); + num_warnings_issued ++; + } } ent->removed = 0; - hdr_info->fde_count++; + hdr_info->u.dwarf.fde_count++; ent->u.fde.cie_inf = find_merged_cie (abfd, info, sec, hdr_info, cookie, ent->u.fde.cie_inf); } @@ -1229,19 +1430,28 @@ _bfd_elf_discard_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) htab = elf_hash_table (info); hdr_info = &htab->eh_info; - if (hdr_info->cies != NULL) + if (!hdr_info->frame_hdr_is_compact && hdr_info->u.dwarf.cies != NULL) { - htab_delete (hdr_info->cies); - hdr_info->cies = NULL; + htab_delete (hdr_info->u.dwarf.cies); + hdr_info->u.dwarf.cies = NULL; } sec = hdr_info->hdr_sec; if (sec == NULL) return FALSE; - sec->size = EH_FRAME_HDR_SIZE; - if (hdr_info->table) - sec->size += 4 + hdr_info->fde_count * 8; + if (info->eh_frame_hdr_type == COMPACT_EH_HDR) + { + /* For compact frames we only add the header. The actual table comes + from the .eh_frame_entry sections. */ + sec->size = 8; + } + else + { + sec->size = EH_FRAME_HDR_SIZE; + if (hdr_info->u.dwarf.table) + sec->size += 4 + hdr_info->u.dwarf.fde_count * 8; + } elf_eh_frame_hdr (abfd) = sec; return TRUE; @@ -1250,6 +1460,7 @@ _bfd_elf_discard_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) /* Return true if there is at least one non-empty .eh_frame section in input files. Can only be called after ld has mapped input to output sections, and before sections are stripped. */ + bfd_boolean _bfd_elf_eh_frame_present (struct bfd_link_info *info) { @@ -1267,6 +1478,29 @@ _bfd_elf_eh_frame_present (struct bfd_link_info *info) return FALSE; } +/* Return true if there is at least one .eh_frame_entry section in + input files. */ + +bfd_boolean +_bfd_elf_eh_frame_entry_present (struct bfd_link_info *info) +{ + asection *o; + bfd *abfd; + + for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link.next) + { + for (o = abfd->sections; o; o = o->next) + { + const char *name = bfd_get_section_name (abfd, o); + + if (strcmp (name, ".eh_frame_entry") + && !bfd_is_abs_section (o->output_section)) + return TRUE; + } + } + return FALSE; +} + /* This function is called from size_dynamic_sections. It needs to decide whether .eh_frame_hdr should be output or not, because when the dynamic symbol table has been sized it is too late @@ -1277,6 +1511,8 @@ _bfd_elf_maybe_strip_eh_frame_hdr (struct bfd_link_info *info) { struct elf_link_hash_table *htab; struct eh_frame_hdr_info *hdr_info; + struct bfd_link_hash_entry *bh = NULL; + struct elf_link_hash_entry *h; htab = elf_hash_table (info); hdr_info = &htab->eh_info; @@ -1284,15 +1520,32 @@ _bfd_elf_maybe_strip_eh_frame_hdr (struct bfd_link_info *info) return TRUE; if (bfd_is_abs_section (hdr_info->hdr_sec->output_section) - || !info->eh_frame_hdr - || !_bfd_elf_eh_frame_present (info)) + || info->eh_frame_hdr_type == 0 + || (info->eh_frame_hdr_type == DWARF2_EH_HDR + && !_bfd_elf_eh_frame_present (info)) + || (info->eh_frame_hdr_type == COMPACT_EH_HDR + && !_bfd_elf_eh_frame_entry_present (info))) { hdr_info->hdr_sec->flags |= SEC_EXCLUDE; hdr_info->hdr_sec = NULL; return TRUE; } - hdr_info->table = TRUE; + /* Add a hidden symbol so that systems without access to PHDRs can + find the table. */ + if (! (_bfd_generic_link_add_one_symbol + (info, info->output_bfd, "__GNU_EH_FRAME_HDR", BSF_LOCAL, + hdr_info->hdr_sec, 0, NULL, FALSE, FALSE, &bh))) + return FALSE; + + h = (struct elf_link_hash_entry *) bh; + h->def_regular = 1; + h->other = STV_HIDDEN; + get_elf_backend_data + (info->output_bfd)->elf_backend_hide_symbol (info, h, TRUE); + + if (!hdr_info->frame_hdr_is_compact) + hdr_info->u.dwarf.table = TRUE; return TRUE; } @@ -1383,6 +1636,83 @@ _bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED, + extra_augmentation_data_bytes (sec_info->entry + mid)); } +/* Write out .eh_frame_entry section. Add CANTUNWIND terminator if needed. + Also check that the contents look sane. */ + +bfd_boolean +_bfd_elf_write_section_eh_frame_entry (bfd *abfd, struct bfd_link_info *info, + asection *sec, bfd_byte *contents) +{ + const struct elf_backend_data *bed; + bfd_byte cantunwind[8]; + bfd_vma addr; + bfd_vma last_addr; + bfd_vma offset; + asection *text_sec = (asection *) elf_section_data (sec)->sec_info; + + if (!sec->rawsize) + sec->rawsize = sec->size; + + BFD_ASSERT (sec->sec_info_type == SEC_INFO_TYPE_EH_FRAME_ENTRY); + + /* Check to make sure that the text section corresponding to this eh_frame_entry + section has not been excluded. In particular, mips16 stub entries will be + excluded outside of the normal process. */ + if (sec->flags & SEC_EXCLUDE + || text_sec->flags & SEC_EXCLUDE) + return TRUE; + + if (!bfd_set_section_contents (abfd, sec->output_section, contents, + sec->output_offset, sec->rawsize)) + return FALSE; + + last_addr = bfd_get_signed_32 (abfd, contents); + /* Check that all the entries are in order. */ + for (offset = 8; offset < sec->rawsize; offset += 8) + { + addr = bfd_get_signed_32 (abfd, contents + offset) + offset; + if (addr <= last_addr) + { + (*_bfd_error_handler) (_("%B: %s not in order"), sec->owner, sec->name); + return FALSE; + } + + last_addr = addr; + } + + addr = text_sec->output_section->vma + text_sec->output_offset + + text_sec->size; + addr &= ~1; + addr -= (sec->output_section->vma + sec->output_offset + sec->rawsize); + if (addr & 1) + { + (*_bfd_error_handler) (_("%B: %s invalid input section size"), + sec->owner, sec->name); + bfd_set_error (bfd_error_bad_value); + return FALSE; + } + if (last_addr >= addr + sec->rawsize) + { + (*_bfd_error_handler) (_("%B: %s points past end of text section"), + sec->owner, sec->name); + bfd_set_error (bfd_error_bad_value); + return FALSE; + } + + if (sec->size == sec->rawsize) + return TRUE; + + bed = get_elf_backend_data (abfd); + BFD_ASSERT (sec->size == sec->rawsize + 8); + BFD_ASSERT ((addr & 1) == 0); + BFD_ASSERT (bed->cant_unwind_opcode); + + bfd_put_32 (abfd, addr, cantunwind); + bfd_put_32 (abfd, (*bed->cant_unwind_opcode) (info), cantunwind + 4); + return bfd_set_section_contents (abfd, sec->output_section, cantunwind, + sec->output_offset + sec->rawsize, 8); +} + /* Write out .eh_frame section. This is called with the relocated contents. */ @@ -1397,6 +1727,7 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, struct eh_frame_hdr_info *hdr_info; unsigned int ptr_size; struct eh_cie_fde *ent; + bfd_size_type sec_size; if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME) /* FIXME: octets_per_byte. */ @@ -1411,10 +1742,14 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, htab = elf_hash_table (info); hdr_info = &htab->eh_info; - if (hdr_info->table && hdr_info->array == NULL) - hdr_info->array = (struct eh_frame_array_ent *) - bfd_malloc (hdr_info->fde_count * sizeof(*hdr_info->array)); - if (hdr_info->array == NULL) + if (hdr_info->u.dwarf.table && hdr_info->u.dwarf.array == NULL) + { + hdr_info->frame_hdr_is_compact = FALSE; + hdr_info->u.dwarf.array = (struct eh_frame_array_ent *) + bfd_malloc (hdr_info->u.dwarf.fde_count + * sizeof (*hdr_info->u.dwarf.array)); + } + if (hdr_info->u.dwarf.array == NULL) hdr_info = NULL; /* The new offsets can be bigger or smaller than the original offsets. @@ -1583,6 +1918,8 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, value = ((ent->new_offset + sec->output_offset + 4) - (cie->new_offset + cie->u.cie.u.sec->output_offset)); bfd_put_32 (abfd, value, buf); + if (bfd_link_relocatable (info)) + continue; buf += 4; width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); value = read_value (abfd, buf, width, @@ -1647,8 +1984,11 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, dwarf_vma is 64-bit. */ if (sizeof (address) > 4 && ptr_size == 4) address &= 0xffffffff; - hdr_info->array[hdr_info->array_count].initial_loc = address; - hdr_info->array[hdr_info->array_count++].fde + hdr_info->u.dwarf.array[hdr_info->array_count].initial_loc + = address; + hdr_info->u.dwarf.array[hdr_info->array_count].range + = read_value (abfd, buf + width, width, FALSE); + hdr_info->u.dwarf.array[hdr_info->array_count++].fde = (sec->output_section->vma + sec->output_offset + ent->new_offset); @@ -1718,7 +2058,11 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, the pointer size. _bfd_elf_discard_section_eh_frame should have padded CIE/FDE records to multiple of pointer size with size_of_output_cie_fde. */ - if ((sec->size % ptr_size) != 0) + sec_size = sec->size; + if (sec_info->count != 0 + && sec_info->entry[sec_info->count - 1].size == 4) + sec_size -= 4; + if ((sec_size % ptr_size) != 0) abort (); /* FIXME: octets_per_byte. */ @@ -1739,13 +2083,118 @@ vma_compare (const void *a, const void *b) return 1; if (p->initial_loc < q->initial_loc) return -1; + if (p->range > q->range) + return 1; + if (p->range < q->range) + return -1; return 0; } -/* Write out .eh_frame_hdr section. This must be called after - _bfd_elf_write_section_eh_frame has been called on all input - .eh_frame sections. - .eh_frame_hdr format: +/* Reorder .eh_frame_entry sections to match the associated text sections. + This routine is called during the final linking step, just before writing + the contents. At this stage, sections in the eh_frame_hdr_info are already + sorted in order of increasing text section address and so we simply need + to make the .eh_frame_entrys follow that same order. Note that it is + invalid for a linker script to try to force a particular order of + .eh_frame_entry sections. */ + +bfd_boolean +_bfd_elf_fixup_eh_frame_hdr (struct bfd_link_info *info) +{ + asection *sec = NULL; + asection *osec; + struct eh_frame_hdr_info *hdr_info; + unsigned int i; + bfd_vma offset; + struct bfd_link_order *p; + + hdr_info = &elf_hash_table (info)->eh_info; + + if (hdr_info->hdr_sec == NULL + || info->eh_frame_hdr_type != COMPACT_EH_HDR + || hdr_info->array_count == 0) + return TRUE; + + /* Change section output offsets to be in text section order. */ + offset = 8; + osec = hdr_info->u.compact.entries[0]->output_section; + for (i = 0; i < hdr_info->array_count; i++) + { + sec = hdr_info->u.compact.entries[i]; + if (sec->output_section != osec) + { + (*_bfd_error_handler) + (_("Invalid output section for .eh_frame_entry: %s"), + sec->output_section->name); + return FALSE; + } + sec->output_offset = offset; + offset += sec->size; + } + + + /* Fix the link_order to match. */ + for (p = sec->output_section->map_head.link_order; p != NULL; p = p->next) + { + if (p->type != bfd_indirect_link_order) + abort(); + + p->offset = p->u.indirect.section->output_offset; + if (p->next != NULL) + i--; + } + + if (i != 0) + { + (*_bfd_error_handler) + (_("Invalid contents in %s section"), osec->name); + return FALSE; + } + + return TRUE; +} + +/* The .eh_frame_hdr format for Compact EH frames: + ubyte version (2) + ubyte eh_ref_enc (DW_EH_PE_* encoding of typinfo references) + uint32_t count (Number of entries in table) + [array from .eh_frame_entry sections] */ + +static bfd_boolean +write_compact_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) +{ + struct elf_link_hash_table *htab; + struct eh_frame_hdr_info *hdr_info; + asection *sec; + const struct elf_backend_data *bed; + bfd_vma count; + bfd_byte contents[8]; + unsigned int i; + + htab = elf_hash_table (info); + hdr_info = &htab->eh_info; + sec = hdr_info->hdr_sec; + + if (sec->size != 8) + abort(); + + for (i = 0; i < sizeof (contents); i++) + contents[i] = 0; + + contents[0] = COMPACT_EH_HDR; + bed = get_elf_backend_data (abfd); + + BFD_ASSERT (bed->compact_eh_encoding); + contents[1] = (*bed->compact_eh_encoding) (info); + + count = (sec->output_section->size - 8) / 8; + bfd_put_32 (abfd, count, contents + 4); + return bfd_set_section_contents (abfd, sec->output_section, contents, + (file_ptr) sec->output_offset, sec->size); +} + +/* The .eh_frame_hdr format for DWARF frames: + ubyte version (currently 1) ubyte eh_frame_ptr_enc (DW_EH_PE_* encoding of pointer to start of .eh_frame section) @@ -1764,8 +2213,8 @@ vma_compare (const void *a, const void *b) FDE initial_location field and FDE address, sorted by increasing initial_loc). */ -bfd_boolean -_bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) +static bfd_boolean +write_dwarf_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) { struct elf_link_hash_table *htab; struct eh_frame_hdr_info *hdr_info; @@ -1775,77 +2224,130 @@ _bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) htab = elf_hash_table (info); hdr_info = &htab->eh_info; sec = hdr_info->hdr_sec; + bfd_byte *contents; + asection *eh_frame_sec; + bfd_size_type size; + bfd_vma encoded_eh_frame; + + size = EH_FRAME_HDR_SIZE; + if (hdr_info->u.dwarf.array + && hdr_info->array_count == hdr_info->u.dwarf.fde_count) + size += 4 + hdr_info->u.dwarf.fde_count * 8; + contents = (bfd_byte *) bfd_malloc (size); + if (contents == NULL) + return FALSE; - if (info->eh_frame_hdr && sec != NULL) + eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame"); + if (eh_frame_sec == NULL) { - bfd_byte *contents; - asection *eh_frame_sec; - bfd_size_type size; - bfd_vma encoded_eh_frame; - - size = EH_FRAME_HDR_SIZE; - if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count) - size += 4 + hdr_info->fde_count * 8; - contents = (bfd_byte *) bfd_malloc (size); - if (contents == NULL) - return FALSE; + free (contents); + return FALSE; + } - eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame"); - if (eh_frame_sec == NULL) - { - free (contents); - return FALSE; - } + memset (contents, 0, EH_FRAME_HDR_SIZE); + /* Version. */ + contents[0] = 1; + /* .eh_frame offset. */ + contents[1] = get_elf_backend_data (abfd)->elf_backend_encode_eh_address + (abfd, info, eh_frame_sec, 0, sec, 4, &encoded_eh_frame); - memset (contents, 0, EH_FRAME_HDR_SIZE); - /* Version. */ - contents[0] = 1; - /* .eh_frame offset. */ - contents[1] = get_elf_backend_data (abfd)->elf_backend_encode_eh_address - (abfd, info, eh_frame_sec, 0, sec, 4, &encoded_eh_frame); + if (hdr_info->u.dwarf.array + && hdr_info->array_count == hdr_info->u.dwarf.fde_count) + { + /* FDE count encoding. */ + contents[2] = DW_EH_PE_udata4; + /* Search table encoding. */ + contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4; + } + else + { + contents[2] = DW_EH_PE_omit; + contents[3] = DW_EH_PE_omit; + } + bfd_put_32 (abfd, encoded_eh_frame, contents + 4); - if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count) + if (contents[2] != DW_EH_PE_omit) + { + unsigned int i; + bfd_boolean overlap, overflow; + + bfd_put_32 (abfd, hdr_info->u.dwarf.fde_count, + contents + EH_FRAME_HDR_SIZE); + qsort (hdr_info->u.dwarf.array, hdr_info->u.dwarf.fde_count, + sizeof (*hdr_info->u.dwarf.array), vma_compare); + overlap = FALSE; + overflow = FALSE; + for (i = 0; i < hdr_info->u.dwarf.fde_count; i++) { - /* FDE count encoding. */ - contents[2] = DW_EH_PE_udata4; - /* Search table encoding. */ - contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4; + bfd_vma val; + + val = hdr_info->u.dwarf.array[i].initial_loc + - sec->output_section->vma; + val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000; + if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 + && (hdr_info->u.dwarf.array[i].initial_loc + != sec->output_section->vma + val)) + overflow = TRUE; + bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 4); + val = hdr_info->u.dwarf.array[i].fde - sec->output_section->vma; + val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000; + if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 + && (hdr_info->u.dwarf.array[i].fde + != sec->output_section->vma + val)) + overflow = TRUE; + bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 8); + if (i != 0 + && (hdr_info->u.dwarf.array[i].initial_loc + < (hdr_info->u.dwarf.array[i - 1].initial_loc + + hdr_info->u.dwarf.array[i - 1].range))) + overlap = TRUE; } - else + if (overflow) + (*info->callbacks->einfo) (_("%P: .eh_frame_hdr entry overflow.\n")); + if (overlap) + (*info->callbacks->einfo) + (_("%P: .eh_frame_hdr refers to overlapping FDEs.\n")); + if (overflow || overlap) { - contents[2] = DW_EH_PE_omit; - contents[3] = DW_EH_PE_omit; + bfd_set_error (bfd_error_bad_value); + retval = FALSE; } - bfd_put_32 (abfd, encoded_eh_frame, contents + 4); + } - if (contents[2] != DW_EH_PE_omit) - { - unsigned int i; + /* FIXME: octets_per_byte. */ + if (!bfd_set_section_contents (abfd, sec->output_section, contents, + (file_ptr) sec->output_offset, + sec->size)) + retval = FALSE; + free (contents); + + if (hdr_info->u.dwarf.array != NULL) + free (hdr_info->u.dwarf.array); + return retval; +} - bfd_put_32 (abfd, hdr_info->fde_count, contents + EH_FRAME_HDR_SIZE); - qsort (hdr_info->array, hdr_info->fde_count, - sizeof (*hdr_info->array), vma_compare); - for (i = 0; i < hdr_info->fde_count; i++) - { - bfd_put_32 (abfd, - hdr_info->array[i].initial_loc - - sec->output_section->vma, - contents + EH_FRAME_HDR_SIZE + i * 8 + 4); - bfd_put_32 (abfd, - hdr_info->array[i].fde - sec->output_section->vma, - contents + EH_FRAME_HDR_SIZE + i * 8 + 8); - } - } +/* Write out .eh_frame_hdr section. This must be called after + _bfd_elf_write_section_eh_frame has been called on all input + .eh_frame sections. */ - /* FIXME: octets_per_byte. */ - retval = bfd_set_section_contents (abfd, sec->output_section, contents, - (file_ptr) sec->output_offset, - sec->size); - free (contents); - } - if (hdr_info->array != NULL) - free (hdr_info->array); - return retval; +bfd_boolean +_bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) +{ + struct elf_link_hash_table *htab; + struct eh_frame_hdr_info *hdr_info; + asection *sec; + + htab = elf_hash_table (info); + hdr_info = &htab->eh_info; + sec = hdr_info->hdr_sec; + + if (info->eh_frame_hdr_type == 0 || sec == NULL) + return TRUE; + + if (info->eh_frame_hdr_type == COMPACT_EH_HDR) + return write_compact_eh_frame_hdr (abfd, info); + else + return write_dwarf_eh_frame_hdr (abfd, info); } /* Return the width of FDE addresses. This is the default implementation. */