Re: [PATCH v2] elf: Reset alignment for each PT_LOAD segment

["H.J. Lu" <hjl.tools@gmail.com>]

On Wed, Aug 3, 2022 at 10:05 AM H.J. Lu <hjl.tools@gmail.com> wrote:
>
> Reset alignment for each PT_LOAD segment to avoid using alignment from
> the previous PT_LOAD segment.
>
> bfd/
>
>         PR ld/29435
>         * elf.c (assign_file_positions_for_load_sections): Reset
>         alignment for each PT_LOAD segment.
>
> ld/
>
>         PR ld/29435
>         * testsuite/ld-elf/pr29435.d: New file.
>         * testsuite/ld-elf/pr29435.s: Likewise.
> ---
>  bfd/elf.c                     |  7 ++++---
>  ld/testsuite/ld-elf/pr29435.d | 11 +++++++++++
>  ld/testsuite/ld-elf/pr29435.s |  6 ++++++
>  3 files changed, 21 insertions(+), 3 deletions(-)
>  create mode 100644 ld/testsuite/ld-elf/pr29435.d
>  create mode 100644 ld/testsuite/ld-elf/pr29435.s
>
> diff --git a/bfd/elf.c b/bfd/elf.c
> index 25f4bca34f0..3e64cdf6699 100644
> --- a/bfd/elf.c
> +++ b/bfd/elf.c
> @@ -5440,8 +5440,6 @@ assign_file_positions_for_load_sections (bfd *abfd,
>    Elf_Internal_Phdr *p;
>    file_ptr off;  /* Octets.  */
>    bfd_size_type maxpagesize;
> -  bfd_size_type p_align;
> -  bool p_align_p = false;
>    unsigned int alloc, actual;
>    unsigned int i, j;
>    struct elf_segment_map **sorted_seg_map;
> @@ -5526,7 +5524,6 @@ assign_file_positions_for_load_sections (bfd *abfd,
>      qsort (sorted_seg_map, alloc, sizeof (*sorted_seg_map),
>            elf_sort_segments);
>
> -  p_align = bed->p_align;
>    maxpagesize = 1;
>    if ((abfd->flags & D_PAGED) != 0)
>      {
> @@ -5561,6 +5558,8 @@ assign_file_positions_for_load_sections (bfd *abfd,
>        asection **secpp;
>        bfd_vma off_adjust;  /* Octets.  */
>        bool no_contents;
> +      bfd_size_type p_align;
> +      bool p_align_p;
>
>        /* An ELF segment (described by Elf_Internal_Phdr) may contain a
>          number of sections with contents contributing to both p_filesz
> @@ -5571,6 +5570,8 @@ assign_file_positions_for_load_sections (bfd *abfd,
>        p = phdrs + m->idx;
>        p->p_type = m->p_type;
>        p->p_flags = m->p_flags;
> +      p_align = bed->p_align;
> +      p_align_p = false;
>
>        if (m->count == 0)
>         p->p_vaddr = m->p_vaddr_offset * opb;
> diff --git a/ld/testsuite/ld-elf/pr29435.d b/ld/testsuite/ld-elf/pr29435.d
> new file mode 100644
> index 00000000000..4ca4fd086a2
> --- /dev/null
> +++ b/ld/testsuite/ld-elf/pr29435.d
> @@ -0,0 +1,11 @@
> +#ld: -shared -z separate-code -z relro
> +#xfail: ![check_shared_lib_support]
> +#xfail: ![check_relro_support]
> +#readelf: -Wl
> +
> +#failif
> +#...
> + +LOAD +0x[0-9a-f]+ 0x[0-9a-f]+ 0x[0-9a-f]+ 0x[0-9a-f]+ 0x[0-9a-f]+ .* 0x8000
> +#...
> + +LOAD +0x[0-9a-f]+ 0x[0-9a-f]+ 0x[0-9a-f]+ 0x[0-9a-f]+ 0x[0-9a-f]+ .* 0x8000
> +#...
> diff --git a/ld/testsuite/ld-elf/pr29435.s b/ld/testsuite/ld-elf/pr29435.s
> new file mode 100644
> index 00000000000..d2d8f265f5e
> --- /dev/null
> +++ b/ld/testsuite/ld-elf/pr29435.s
> @@ -0,0 +1,6 @@
> +        .text
> +       .balign 0x8000
> +       .globl  foo
> +       .type   foo, %function
> +foo:
> +       .byte 0
> --
> 2.37.1
>

Hi Nick,

Is it OK to backport to 2.38 and 2.39 branches?

Thanks.

-- 
H.J.