Re: [PATCH, COMMITTED]: Fix seg fault in elf32.em:_after_open

[Pedro Alves <pedro at codesourcery dot com>]

On Friday 20 August 2010 16:00:30, Nick Clifton wrote:
>   Whilst working on another bug I came across a seg-fault in the
>   _after_open() function in elf32.em.  If the target is not an ELF
>   binary then get_elf_backend_data will return NULL, but the code was
>   not checking for this.  Fixed by applying the following patch.

(...)

>           bed = get_elf_backend_data (abfd);
> !         if (bed == NULL)
> !           s = NULL;
> !         else
> !           s = bfd_make_section_with_flags (abfd, ".eh_frame_hdr",
> !                                            bed->dynamic_sec_flags
> !                                            | SEC_READONLY);

Is it valid to call get_elf_backend_data on a non-elf bfd at all?

#define get_elf_backend_data(abfd) \
   xvec_get_elf_backend_data ((abfd)->xvec)

#define bfd_mach_o_get_backend_data(abfd) \
  ((bfd_mach_o_backend_data*)(abfd)->xvec->backend_data)

.#define coff_backend_info(abfd) \
.  ((bfd_coff_backend_data *) (abfd)->xvec->backend_data)

It appears that for other flavours, it may happen to return
something undefined.

Shouldn't that check be something like
bfd_get_flavour (abfd) != bfd_target_elf_flavour instead?

-- 
Pedro Alves