Re: [PATCH v7 22/27] binfmt_elf: Extract .note.gnu.property from an ELF file

From: Florian Weimer
Date: Tue Jun 18 2019 - 12:10:53 EST


* Yu-cheng Yu:

>> I assumed that it would also parse the main executable and make
>> adjustments based on that.
>
> Yes, Linux also looks at the main executable's header, but not its
> NT_GNU_PROPERTY_TYPE_0 if there is a loader.
>
>>
>> ld.so can certainly provide whatever the kernel needs. We need to tweak
>> the existing loader anyway.
>>
>> No valid statically-linked binaries exist today, so this is not a
>> consideration at this point.
>
> So from kernel, we look at only PT_GNU_PROPERTY?

If you don't parse notes/segments in the executable for CET, then yes.
We can put PT_GNU_PROPERTY into the loader.

Thanks,
Florian