Do not generate GNU build notes for linkonce sections.

Resolves: #1576362
This commit is contained in:
Nick Clifton 2018-05-14 16:02:15 +01:00
parent 1f337663ab
commit e2612ee0fe
2 changed files with 134 additions and 0 deletions

View File

@ -0,0 +1,127 @@
--- binutils.orig/gas/write.c 2018-05-14 12:22:27.893671804 +0100
+++ binutils-2.30/gas/write.c 2018-05-14 15:39:03.900509629 +0100
@@ -1901,6 +1901,7 @@ maybe_generate_build_notes (void)
segT sec;
char * note;
offsetT note_size;
+ offsetT total_size;
offsetT desc_size;
offsetT desc2_offset;
int desc_reloc;
@@ -1918,7 +1919,8 @@ maybe_generate_build_notes (void)
SEC_READONLY | SEC_HAS_CONTENTS | SEC_DATA);
bfd_set_section_alignment (stdoutput, sec, 2);
- /* Create a version note. */
+ /* Work out the size of the notes that we will create,
+ and the relocation we should use. */
if (bfd_arch_bits_per_address (stdoutput) <= 32)
{
note_size = 28;
@@ -1952,65 +1954,59 @@ maybe_generate_build_notes (void)
desc_reloc = BFD_RELOC_64;
}
- frag_now_fix ();
- note = frag_more (note_size);
- memset (note, 0, note_size);
+ /* We have to create a note for *each* code section.
+ Linker garbage collection might discard some. */
+ total_size = 0;
+ note = NULL;
- if (target_big_endian)
- {
- note[3] = 8; /* strlen (name) + 1. */
- note[7] = desc_size; /* Two 8-byte offsets. */
- note[10] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8;
- note[11] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff;
- }
- else
- {
- note[0] = 8; /* strlen (name) + 1. */
- note[4] = desc_size; /* Two 8-byte offsets. */
- note[8] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff;
- note[9] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8;
- }
-
- /* The a1 version number indicates that this note was
- generated by the assembler and not the gcc annobin plugin. */
- memcpy (note + 12, "GA$3a1", 8);
-
- /* Find the first code section symbol. */
for (sym = symbol_rootP; sym != NULL; sym = sym->sy_next)
if (sym->bsym != NULL
&& sym->bsym->flags & BSF_SECTION_SYM
&& sym->bsym->section != NULL
- && sym->bsym->section->flags & SEC_CODE)
+ /* Skip linkonce sections - we cannot these section symbols as they may disappear. */
+ && (sym->bsym->section->flags & (SEC_CODE | SEC_LINK_ONCE)) == SEC_CODE
+ /* Not all linkonce sections are flagged... */
+ && strncmp (S_GET_NAME (sym), ".gnu.linkonce", sizeof ".gnu.linkonce" - 1) != 0)
{
- /* Found one - now create a relocation against this symbol. */
- create_note_reloc (sec, sym, 20, desc_reloc, 0, note);
- break;
- }
+ /* Create a version note. */
+ frag_now_fix ();
+ note = frag_more (note_size);
+ memset (note, 0, note_size);
- /* Find the last code section symbol. */
- if (sym)
- {
- for (sym = symbol_lastP; sym != NULL; sym = sym->sy_previous)
- if (sym->bsym != NULL
- && sym->bsym->flags & BSF_SECTION_SYM
- && sym->bsym->section != NULL
- && sym->bsym->section->flags & SEC_CODE)
+ if (target_big_endian)
{
- /* Create a relocation against the end of this symbol. */
- create_note_reloc (sec, sym, desc2_offset, desc_reloc,
- bfd_get_section_size (sym->bsym->section),
- note);
- break;
+ note[3] = 8; /* strlen (name) + 1. */
+ note[7] = desc_size; /* Two 8-byte offsets. */
+ note[10] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8;
+ note[11] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff;
}
- }
- /* else - if we were unable to find any code section symbols then
- probably there is no code in the output. So leaving the start
- and end values as zero in the note is OK. */
+ else
+ {
+ note[0] = 8; /* strlen (name) + 1. */
+ note[4] = desc_size; /* Two 8-byte offsets. */
+ note[8] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff;
+ note[9] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8;
+ }
+
+ /* The a1 version number indicates that this note was
+ generated by the assembler and not the gcc annobin plugin. */
+ memcpy (note + 12, "GA$3a1", 8);
- /* FIXME: Maybe add a note recording the assembler command line and version ? */
+ /* Create a relocation to install the start address of the note... */
+ create_note_reloc (sec, sym, 20, desc_reloc, 0, note);
+
+ /* ...and another one to install the end address. */
+ create_note_reloc (sec, sym, desc2_offset, desc_reloc,
+ bfd_get_section_size (sym->bsym->section),
+ note);
+
+ total_size += note_size;
+ /* FIXME: Maybe add a note recording the assembler command line and version ? */
+ }
/* Install the note(s) into the section. */
- bfd_set_section_contents (stdoutput, sec, (bfd_byte *) note, 0, note_size);
+ if (total_size)
+ bfd_set_section_contents (stdoutput, sec, (bfd_byte *) note, 0, total_size);
subsegs_finish_section (sec);
relax_segment (seg_info (sec)->frchainP->frch_root, sec, 0);
size_seg (stdoutput, sec, NULL);

View File

@ -270,6 +270,11 @@ Patch32: binutils-CVE-2018-10535.patch
# Lifetime: Fixed in 2.31
Patch33: binutils-x86-local-relocs.patch
# Purpose: Stop the assembler from generating GNU build notes against
# linkonce sections.
# Lifetime: Fixed in 2.31
Patch34: binutils-linkonce-notes.patch
#----------------------------------------------------------------------------
Provides: bundled(libiberty)
@ -428,6 +433,7 @@ using libelf instead of BFD.
%patch31 -p1
%patch32 -p1
%patch33 -p1
%patch34 -p1
# We cannot run autotools as there is an exact requirement of autoconf-2.59.
@ -843,6 +849,7 @@ exit 0
%changelog
* Mon May 14 2018 Nick Clifton <nickc@redhat.com> 2.30-20
- Have the x86 linker resolve relocations against the _end, _edata and __bss_start symbols locally. (#1576735)
- Do not generate GNU build notes for linkonce sections. (#1576362)
* Thu May 10 2018 Nick Clifton <nickc@redhat.com> 2.30-19
- Fix a seg-fault running objcopy on a corrupt PE format file. (#1574702)