Re: CVS commit: src/external/gpl3

[maya%netbsd.org@localhost]

so, number of segments will be wrong if there is .interp but no
.dynamic.

why don't we ignore the conventrion set in this file and ++segs when
adding those segments?

On Thu, Jul 12, 2018 at 09:38:16PM +0000, Joerg Sonnenberger wrote:
> Module Name:	src
> Committed By:	joerg
> Date:		Thu Jul 12 21:38:16 UTC 2018
> 
> Modified Files:
> 	src/external/gpl3/binutils.old/dist/bfd: elf.c
> 	src/external/gpl3/binutils/dist/bfd: elf.c
> 
> Log Message:
> PT_PHDR is useful without PT_INTERP, i.e. for static PIE. It removes the
> need for platform-specific computations of _DYNAMIC and friends.
> 
> 
> To generate a diff of this commit:
> cvs rdiff -u -r1.5 -r1.6 src/external/gpl3/binutils.old/dist/bfd/elf.c
> cvs rdiff -u -r1.9 -r1.10 src/external/gpl3/binutils/dist/bfd/elf.c
> 
> Please note that diffs are not public domain; they are subject to the
> copyright notices on the relevant files.
> 

> Modified files:
> 
> Index: src/external/gpl3/binutils.old/dist/bfd/elf.c
> diff -u src/external/gpl3/binutils.old/dist/bfd/elf.c:1.5 src/external/gpl3/binutils.old/dist/bfd/elf.c:1.6
> --- src/external/gpl3/binutils.old/dist/bfd/elf.c:1.5	Sat Apr 14 15:49:38 2018
> +++ src/external/gpl3/binutils.old/dist/bfd/elf.c	Thu Jul 12 21:38:16 2018
> @@ -4159,7 +4159,7 @@ static bfd_size_type
>  get_program_header_size (bfd *abfd, struct bfd_link_info *info)
>  {
>    size_t segs;
> -  asection *s;
> +  asection *s, *s2;
>    const struct elf_backend_data *bed;
>  
>    /* Assume we will need exactly two PT_LOAD segments: one for text
> @@ -4167,21 +4167,28 @@ get_program_header_size (bfd *abfd, stru
>    segs = 2;
>  
>    s = bfd_get_section_by_name (abfd, ".interp");
> +  s2 = bfd_get_section_by_name (abfd, ".dynamic");
>    if (s != NULL && (s->flags & SEC_LOAD) != 0)
>      {
> -      /* If we have a loadable interpreter section, we need a
> -	 PT_INTERP segment.  In this case, assume we also need a
> -	 PT_PHDR segment, although that may not be true for all
> -	 targets.  */
> -      segs += 2;
> +      ++segs;
>      }
>  
> -  if (bfd_get_section_by_name (abfd, ".dynamic") != NULL)
> +  if (s2 != NULL && (s2->flags & SEC_LOAD) != 0)
>      {
>        /* We need a PT_DYNAMIC segment.  */
>        ++segs;
>      }
>  
> +  if ((s != NULL && (s->flags & SEC_LOAD) != 0) ||
> +      (s2 != NULL && (s2->flags & SEC_LOAD) != 0))
> +    {
> +      /*
> +       * If either a PT_INTERP or PT_DYNAMIC segment is created,
> +       * also create a PT_PHDR segment.
> +       */
> +      ++segs;
> +    }
> +
>    if (info != NULL && info->relro)
>      {
>        /* We need a PT_GNU_RELRO segment.  */
> @@ -4448,6 +4455,13 @@ _bfd_elf_map_sections_to_segments (bfd *
>  	 section.  */
>        s = bfd_get_section_by_name (abfd, ".interp");
>        if (s != NULL && (s->flags & SEC_LOAD) != 0)
> +	s = NULL;
> +      dynsec = bfd_get_section_by_name (abfd, ".dynamic");
> +      if (dynsec != NULL
> +	  && (dynsec->flags & SEC_LOAD) == 0)
> +	dynsec = NULL;
> +
> +      if (s != NULL || dynsec != NULL)
>  	{
>  	  amt = sizeof (struct elf_segment_map);
>  	  m = (struct elf_segment_map *) bfd_zalloc (abfd, amt);
> @@ -4462,7 +4476,10 @@ _bfd_elf_map_sections_to_segments (bfd *
>  
>  	  *pm = m;
>  	  pm = &m->next;
> +	}
>  
> +      if (s != NULL)
> +	{
>  	  amt = sizeof (struct elf_segment_map);
>  	  m = (struct elf_segment_map *) bfd_zalloc (abfd, amt);
>  	  if (m == NULL)
> @@ -4489,10 +4506,6 @@ _bfd_elf_map_sections_to_segments (bfd *
>        if (maxpagesize == 0)
>  	maxpagesize = 1;
>        writable = FALSE;
> -      dynsec = bfd_get_section_by_name (abfd, ".dynamic");
> -      if (dynsec != NULL
> -	  && (dynsec->flags & SEC_LOAD) == 0)
> -	dynsec = NULL;
>  
>        /* Deal with -Ttext or something similar such that the first section
>  	 is not adjacent to the program headers.  This is an
> 
> Index: src/external/gpl3/binutils/dist/bfd/elf.c
> diff -u src/external/gpl3/binutils/dist/bfd/elf.c:1.9 src/external/gpl3/binutils/dist/bfd/elf.c:1.10
> --- src/external/gpl3/binutils/dist/bfd/elf.c:1.9	Sun Apr 15 20:06:01 2018
> +++ src/external/gpl3/binutils/dist/bfd/elf.c	Thu Jul 12 21:38:16 2018
> @@ -4301,7 +4301,7 @@ static bfd_size_type
>  get_program_header_size (bfd *abfd, struct bfd_link_info *info)
>  {
>    size_t segs;
> -  asection *s;
> +  asection *s, *s2;
>    const struct elf_backend_data *bed;
>  
>    /* Assume we will need exactly two PT_LOAD segments: one for text
> @@ -4309,21 +4309,28 @@ get_program_header_size (bfd *abfd, stru
>    segs = 2;
>  
>    s = bfd_get_section_by_name (abfd, ".interp");
> +  s2 = bfd_get_section_by_name (abfd, ".dynamic");
>    if (s != NULL && (s->flags & SEC_LOAD) != 0)
>      {
> -      /* If we have a loadable interpreter section, we need a
> -	 PT_INTERP segment.  In this case, assume we also need a
> -	 PT_PHDR segment, although that may not be true for all
> -	 targets.  */
> -      segs += 2;
> +      ++segs;
>      }
>  
> -  if (bfd_get_section_by_name (abfd, ".dynamic") != NULL)
> +  if (s2 != NULL && (s2->flags & SEC_LOAD) != 0)
>      {
>        /* We need a PT_DYNAMIC segment.  */
>        ++segs;
>      }
>  
> +  if ((s != NULL && (s->flags & SEC_LOAD) != 0) ||
> +      (s2 != NULL && (s2->flags & SEC_LOAD) != 0))
> +    {
> +      /*
> +       * If either a PT_INTERP or PT_DYNAMIC segment is created,
> +       * also create a PT_PHDR segment.
> +       */
> +      ++segs;
> +    }
> +
>    if (info != NULL && info->relro)
>      {
>        /* We need a PT_GNU_RELRO segment.  */
> @@ -4620,6 +4627,13 @@ _bfd_elf_map_sections_to_segments (bfd *
>  	 section.  */
>        s = bfd_get_section_by_name (abfd, ".interp");
>        if (s != NULL && (s->flags & SEC_LOAD) != 0)
> +	s = NULL;
> +      dynsec = bfd_get_section_by_name (abfd, ".dynamic");
> +      if (dynsec != NULL
> +	  && (dynsec->flags & SEC_LOAD) == 0)
> +	dynsec = NULL;
> +
> +      if (s != NULL || dynsec != NULL)
>  	{
>  	  amt = sizeof (struct elf_segment_map);
>  	  m = (struct elf_segment_map *) bfd_zalloc (abfd, amt);
> @@ -4633,7 +4647,10 @@ _bfd_elf_map_sections_to_segments (bfd *
>  	  linker_created_pt_phdr_segment = TRUE;
>  	  *pm = m;
>  	  pm = &m->next;
> +	}
>  
> +      if (s != NULL)
> +	{
>  	  amt = sizeof (struct elf_segment_map);
>  	  m = (struct elf_segment_map *) bfd_zalloc (abfd, amt);
>  	  if (m == NULL)
> @@ -4661,10 +4678,6 @@ _bfd_elf_map_sections_to_segments (bfd *
>  	maxpagesize = 1;
>        writable = FALSE;
>        executable = FALSE;
> -      dynsec = bfd_get_section_by_name (abfd, ".dynamic");
> -      if (dynsec != NULL
> -	  && (dynsec->flags & SEC_LOAD) == 0)
> -	dynsec = NULL;
>  
>        /* Deal with -Ttext or something similar such that the first section
>  	 is not adjacent to the program headers.  This is an
>