Re: [PATCH] elf: Add elf checks for main executable

[Florian Weimer <fweimer@redhat.com>]

* Adhemerval Zanella:

> On 06/12/2021 16:22, H.J. Lu wrote:
>> On Mon, Dec 6, 2021 at 11:09 AM Florian Weimer <fweimer@redhat.com> wrote:
>>>
>>> * Adhemerval Zanella:
>>>
>>>> +static void
>>>> +modify_abiversion (ElfW(Ehdr) *ehdr)
>>>> +{
>>>> +  ehdr->e_ident[EI_ABIVERSION] = LIBC_ABI_MAX;
>>>> +}
>>>
>>> So this is eventually controlled by the libc-abis file, right?
>>>
>>> I *thought* that the consensus was that binutils should bump version if
>>> absolute symbols are used.  But I don't see that in the absolute symbol
>>> tests.
>>>
>>> Is this really doing anything?
>>>
>> 
>> EI_ABIVERSION check works on executables created by the new linker
>> which bumps EI_ABIVERSION.  This complements the existing
>> EI_ABIVERSION check on DSOs.  This is orthogonal to the ABI version
>> check for existing ld.so binaries which needs an ABIVERSION version.
>> 
>
> Currently only mips does actually set and checks different EI_ABIVERSION
> through VALID_ELF_ABIVERSION. For instance, -Wl,--hash-style=gnu with
> mips64 will set EI_ABIVERSION to 5.

What surprised me is that binutils does not seem to *generate* the bump
for ABSOLUTE.  Not so much the lack of checking in glibc.

Thanks,
Florian