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Revert "elf: Remove the 1-page gap before the RELRO segment"

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This reverts commit 2f83249c13.

	PR ld/28743
	* ldlang.c (lang_size_relro_segment_1): Revert 2022-01-10 changes.
	* testsuite/ld-i386/pr20830.d: Likewise.
	* testsuite/ld-s390/gotreloc_64-relro-1.dd: Likewise.
	* testsuite/ld-x86-64/pr14207.d: Likewise.
	* testsuite/ld-x86-64/pr18176.d: Likewise.
	* testsuite/ld-x86-64/pr20830a-now.d: Likewise.
	* testsuite/ld-x86-64/pr20830a.d: Likewise.
	* testsuite/ld-x86-64/pr20830b-now.d: Likewise.
	* testsuite/ld-x86-64/pr20830b.d: Likewise.
	* testsuite/ld-x86-64/pr21038a-now.d: Likewise.
	* testsuite/ld-x86-64/pr21038a.d: Likewise.
	* testsuite/ld-x86-64/pr21038b-now.d: Likewise.
	* testsuite/ld-x86-64/pr21038c-now.d: Likewise.
	* testsuite/ld-x86-64/pr21038c.d: Likewise.
This commit is contained in:
Alan Modra
2022-02-05 20:06:52 +10:30
parent 5197c88e2a
commit 6a9d08661b
14 changed files with 56 additions and 109 deletions
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87
ld/ldlang.c
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@@ -6371,9 +6371,7 @@ static bfd_vma
lang_size_relro_segment_1 (seg_align_type *seg)
{
bfd_vma relro_end, desired_end;
asection *sec, *prev_sec = NULL;
bool remove_page_gap = false;
unsigned int max_alignment_power = 0;
asection *sec;
/* Compute the expected PT_GNU_RELRO/PT_LOAD segment end. */
relro_end = ((seg->relro_end + seg->pagesize - 1)
@@ -6384,79 +6382,28 @@ lang_size_relro_segment_1 (seg_align_type *seg)
/* For sections in the relro segment.. */
for (sec = link_info.output_bfd->section_last; sec; sec = sec->prev)
if ((sec->flags & SEC_ALLOC) != 0)
if ((sec->flags & SEC_ALLOC) != 0
&& sec->vma >= seg->base
&& sec->vma < seg->relro_end - seg->relro_offset)
{
if (sec->alignment_power > max_alignment_power)
max_alignment_power = sec->alignment_power;
/* Where do we want to put this section so that it ends as
desired? */
bfd_vma start, end, bump;
if (sec->vma >= seg->base
&& sec->vma < seg->relro_end - seg->relro_offset)
{
/* Where do we want to put this section so that it ends as
desired? */
bfd_vma start, end, bump;
end = start = sec->vma;
if (!IS_TBSS (sec))
end += TO_ADDR (sec->size);
bump = desired_end - end;
/* We'd like to increase START by BUMP, but we must heed
alignment so the increase might be less than optimum. */
start += bump;
start &= ~(((bfd_vma) 1 << sec->alignment_power) - 1);
/* This is now the desired end for the previous section. */
desired_end = start;
prev_sec = sec->prev;
}
end = start = sec->vma;
if (!IS_TBSS (sec))
end += TO_ADDR (sec->size);
bump = desired_end - end;
/* We'd like to increase START by BUMP, but we must heed
alignment so the increase might be less than optimum. */
start += bump;
start &= ~(((bfd_vma) 1 << sec->alignment_power) - 1);
/* This is now the desired end for the previous section. */
desired_end = start;
}
seg->phase = exp_seg_relro_adjust;
ASSERT (desired_end >= seg->base);
for (; prev_sec; prev_sec = prev_sec->prev)
if ((prev_sec->flags & SEC_ALLOC) != 0)
{
if (prev_sec->alignment_power > max_alignment_power)
max_alignment_power = prev_sec->alignment_power;
if (prev_sec->size != 0)
{
/* The 1-page gap before the RELRO segment may be removed. */
remove_page_gap = ((prev_sec->vma + prev_sec->size
+ seg->maxpagesize) < desired_end);
break;
}
}
if (remove_page_gap)
{
/* Find the maximum section alignment. */
for (sec = prev_sec; sec; sec = sec->prev)
if ((sec->flags & SEC_ALLOC) != 0
&& sec->alignment_power > max_alignment_power)
max_alignment_power = sec->alignment_power;
/* Remove the 1-page gap before the RELRO segment only if the
maximum page size >= the maximum section alignment. */
if (seg->maxpagesize >= (1U << max_alignment_power))
{
/* If the preceding section size is greater than the maximum
page size, subtract the maximum page size. Otherwise,
align the RELRO segment to the maximum page size. */
if (prev_sec->size > seg->maxpagesize)
{
desired_end -= seg->maxpagesize;
relro_end -= seg->maxpagesize;
}
else
{
desired_end &= ~(seg->maxpagesize - 1);
relro_end &= ~(seg->maxpagesize - 1);
}
}
}
seg->base = desired_end;
return relro_end;
}