Re: [PATCH v4 14/17] arm/build: Warn on orphan section placement

From: Arvind Sankar
Date: Mon Jun 29 2020 - 15:33:36 EST


On Sun, Jun 28, 2020 at 11:18:37PM -0700, Kees Cook wrote:
> We don't want to depend on the linker's orphan section placement
> heuristics as these can vary between linkers, and may change between
> versions. All sections need to be explicitly named in the linker
> script.
>
> Specifically, this would have made a recently fixed bug very obvious:
>
> ld: warning: orphan section `.fixup' from `arch/arm/lib/copy_from_user.o' being placed in section `.fixup'
>
> Discard unneeded sections .iplt, .rel.iplt, .igot.plt, and .modinfo.
>
> Add missing text stub sections .vfp11_veneer and .v4_bx.
>
> Add debug sections explicitly.
>
> Finally enable orphan section warning.

This is unrelated to this patch as such, but I noticed that ARM32/64 places
the .got section inside .text -- is that expected on ARM?