diff options
Diffstat (limited to 'gold/object.cc')
| -rw-r--r-- | gold/object.cc | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/gold/object.cc b/gold/object.cc index 2b58f04..8c874fe 100644 --- a/gold/object.cc +++ b/gold/object.cc @@ -1282,6 +1282,102 @@ Sized_relobj_file<size, big_endian>::layout_eh_frame_section( this->set_relocs_must_follow_section_writes(); } +// Layout an input .note.gnu.property section. + +// This note section has an *extremely* non-standard layout. +// The gABI spec says that ELF-64 files should have 8-byte fields and +// 8-byte alignment in the note section, but the Gnu tools generally +// use 4-byte fields and 4-byte alignment (see the comment for +// Layout::create_note). This section uses 4-byte fields (i.e., +// namesz, descsz, and type are always 4 bytes), the name field is +// padded to a multiple of 4 bytes, but the desc field is padded +// to a multiple of 4 or 8 bytes, depending on the ELF class. +// The individual properties within the desc field always use +// 4-byte pr_type and pr_datasz fields, but pr_data is padded to +// a multiple of 4 or 8 bytes, depending on the ELF class. + +template<int size, bool big_endian> +void +Sized_relobj_file<size, big_endian>::layout_gnu_property_section( + Layout* layout, + unsigned int shndx) +{ + section_size_type contents_len; + const unsigned char* pcontents = this->section_contents(shndx, + &contents_len, + false); + const unsigned char* pcontents_end = pcontents + contents_len; + + // Loop over all the notes in this section. + while (pcontents < pcontents_end) + { + if (pcontents + 16 > pcontents_end) + { + gold_warning(_("%s: corrupt .note.gnu.property section " + "(note too short)"), + this->name().c_str()); + return; + } + + size_t namesz = elfcpp::Swap<32, big_endian>::readval(pcontents); + size_t descsz = elfcpp::Swap<32, big_endian>::readval(pcontents + 4); + unsigned int ntype = elfcpp::Swap<32, big_endian>::readval(pcontents + 8); + const unsigned char* pname = pcontents + 12; + + if (namesz != 4 || strcmp(reinterpret_cast<const char*>(pname), "GNU") != 0) + { + gold_warning(_("%s: corrupt .note.gnu.property section " + "(name is not 'GNU')"), + this->name().c_str()); + return; + } + + if (ntype != elfcpp::NT_GNU_PROPERTY_TYPE_0) + { + gold_warning(_("%s: unsupported note type %d " + "in .note.gnu.property section"), + this->name().c_str(), ntype); + return; + } + + size_t aligned_namesz = align_address(namesz, 4); + const unsigned char* pdesc = pname + aligned_namesz; + + if (pdesc + descsz > pcontents + contents_len) + { + gold_warning(_("%s: corrupt .note.gnu.property section"), + this->name().c_str()); + return; + } + + const unsigned char* pprop = pdesc; + + // Loop over the program properties in this note. + while (pprop < pdesc + descsz) + { + if (pprop + 8 > pdesc + descsz) + { + gold_warning(_("%s: corrupt .note.gnu.property section"), + this->name().c_str()); + return; + } + unsigned int pr_type = elfcpp::Swap<32, big_endian>::readval(pprop); + size_t pr_datasz = elfcpp::Swap<32, big_endian>::readval(pprop + 4); + pprop += 8; + if (pprop + pr_datasz > pdesc + descsz) + { + gold_warning(_("%s: corrupt .note.gnu.property section"), + this->name().c_str()); + return; + } + layout->layout_gnu_property(ntype, pr_type, pr_datasz, pprop, this); + pprop += align_address(pr_datasz, size / 8); + } + + pcontents = pdesc + align_address(descsz, size / 8); + } +} + // Lay out the input sections. We walk through the sections and check // whether they should be included in the link. If they should, we // pass them to the Layout object, which will return an output section @@ -1538,6 +1634,14 @@ Sized_relobj_file<size, big_endian>::do_layout(Symbol_table* symtab, omit[i] = true; } + // Handle .note.gnu.property sections. + if (sh_type == elfcpp::SHT_NOTE + && strcmp(name, ".note.gnu.property") == 0) + { + this->layout_gnu_property_section(layout, i); + omit[i] = true; + } + bool discard = omit[i]; if (!discard) { |