From 23e463ed7c0d289e2291aaefd576bf02efd98df8 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Wed, 3 Oct 2018 13:22:26 -0700 Subject: [PATCH] ELF: Group PT_NOTE segments by section alignments Alignments of SHT_NOTE sections can be 8 bytes for 64-bit ELF files. We should put all adjacent SHT_NOTE sections with the same section alignment into a single PT_NOTE segment even when the section alignment != 4 bytes. Also check SHT_NOTE section type instead of section name. PR ld/23658 * elf.c (get_program_header_size): Put all adjacent SHT_NOTE sections with the same section alignment into a single PT_NOTE segment. Check SHT_NOTE section type instead of section name. (_bfd_elf_map_sections_to_segments): Likewise. --- bfd/ChangeLog | 8 +++++++ bfd/elf.c | 59 +++++++++++++++++++++++++-------------------------- 2 files changed, 37 insertions(+), 30 deletions(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 122983cb18b..d2b5a57fe78 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,11 @@ +2018-10-03 H.J. Lu + + PR ld/23658 + * elf.c (get_program_header_size): Put all adjacent SHT_NOTE + sections with the same section alignment into a single PT_NOTE + segment. Check SHT_NOTE section type instead of section name. + (_bfd_elf_map_sections_to_segments): Likewise. + 2018-10-03 Millan Wolff PR 23715 diff --git a/bfd/elf.c b/bfd/elf.c index 5320ae2237f..8850efe20e9 100644 --- a/bfd/elf.c +++ b/bfd/elf.c @@ -4371,23 +4371,22 @@ get_program_header_size (bfd *abfd, struct bfd_link_info *info) for (s = abfd->sections; s != NULL; s = s->next) { if ((s->flags & SEC_LOAD) != 0 - && CONST_STRNEQ (s->name, ".note")) + && elf_section_type (s) == SHT_NOTE) { + unsigned int alignment_power; /* We need a PT_NOTE segment. */ ++segs; - /* Try to create just one PT_NOTE segment - for all adjacent loadable .note* sections. - gABI requires that within a PT_NOTE segment - (and also inside of each SHT_NOTE section) - each note is padded to a multiple of 4 size, - so we check whether the sections are correctly - aligned. */ - if (s->alignment_power == 2) - while (s->next != NULL - && s->next->alignment_power == 2 - && (s->next->flags & SEC_LOAD) != 0 - && CONST_STRNEQ (s->next->name, ".note")) - s = s->next; + /* Try to create just one PT_NOTE segment for all adjacent + loadable SHT_NOTE sections. gABI requires that within a + PT_NOTE segment (and also inside of each SHT_NOTE section) + each note should have the same alignment. So we check + whether the sections are correctly aligned. */ + alignment_power = s->alignment_power; + while (s->next != NULL + && s->next->alignment_power == alignment_power + && (s->next->flags & SEC_LOAD) != 0 + && elf_section_type (s->next) == SHT_NOTE) + s = s->next; } } @@ -4885,33 +4884,33 @@ _bfd_elf_map_sections_to_segments (bfd *abfd, struct bfd_link_info *info) pm = &m->next; } - /* For each batch of consecutive loadable .note sections, + /* For each batch of consecutive loadable SHT_NOTE sections, add a PT_NOTE segment. We don't use bfd_get_section_by_name, because if we link together nonloadable .note sections and loadable .note sections, we will generate two .note sections - in the output file. FIXME: Using names for section types is - bogus anyhow. */ + in the output file. */ for (s = abfd->sections; s != NULL; s = s->next) { if ((s->flags & SEC_LOAD) != 0 - && CONST_STRNEQ (s->name, ".note")) + && elf_section_type (s) == SHT_NOTE) { asection *s2; + unsigned int alignment_power = s->alignment_power; count = 1; amt = sizeof (struct elf_segment_map); - if (s->alignment_power == 2) - for (s2 = s; s2->next != NULL; s2 = s2->next) - { - if (s2->next->alignment_power == 2 - && (s2->next->flags & SEC_LOAD) != 0 - && CONST_STRNEQ (s2->next->name, ".note") - && align_power (s2->lma + s2->size, 2) - == s2->next->lma) - count++; - else - break; - } + for (s2 = s; s2->next != NULL; s2 = s2->next) + { + if (s2->next->alignment_power == alignment_power + && (s2->next->flags & SEC_LOAD) != 0 + && elf_section_type (s2->next) == SHT_NOTE + && align_power (s2->lma + s2->size, + alignment_power) + == s2->next->lma) + count++; + else + break; + } amt += (count - 1) * sizeof (asection *); m = (struct elf_segment_map *) bfd_zalloc (abfd, amt); if (m == NULL) -- 2.30.2