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From: Arvind Sankar <nivedita@alum.mit.edu>
Date: Mon, 29 Jun 2020 11:54:01 -0400
Subject: Re: [PATCH v4 14/17] arm/build: Warn on orphan section placement
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To: Kees Cook <keescook@chromium.org>
Cc: Will Deacon <will@kernel.org>, Catalin Marinas <catalin.marinas@arm.com>, Mark Rutland <mark.rutland@arm.com>, Ard Biesheuvel <ardb@kernel.org>, Peter Collingbourne <pcc@google.com>, James Morse <james.morse@arm.com>, Borislav Petkov <bp@suse.de>, Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>, Russell King <linux@armlinux.org.uk>, Masahiro Yamada <masahiroy@kernel.org>, Arvind Sankar <nivedita@alum.mit.edu>, Nick Desaulniers <ndesaulniers@google.com>, Nathan Chancellor <natechancellor@gmail.com>, Arnd Bergmann <arnd@arndb.de>, x86@kernel.org, clang-built-linux@googlegroups.com, linux-arch@vger.kernel.org, linux-efi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
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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?