From 5a17850e251a55bba6d65aefbfeacfa9888cd2cd Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 1 Sep 2020 19:53:44 -0700 Subject: arm/build: Warn on orphan section placement 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 handled 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' With all sections handled, enable orphan section warning. Signed-off-by: Kees Cook Signed-off-by: Ingo Molnar Reviewed-by: Nick Desaulniers Link: https://lore.kernel.org/r/20200902025347.2504702-3-keescook@chromium.org --- arch/arm/Makefile | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'arch/arm/Makefile') diff --git a/arch/arm/Makefile b/arch/arm/Makefile index 4e877354515f..e589da3c8949 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -16,6 +16,10 @@ LDFLAGS_vmlinux += --be8 KBUILD_LDFLAGS_MODULE += --be8 endif +# We never want expected sections to be placed heuristically by the +# linker. All sections should be explicitly named in the linker script. +LDFLAGS_vmlinux += $(call ld-option, --orphan-handling=warn) + ifeq ($(CONFIG_ARM_MODULE_PLTS),y) KBUILD_LDS_MODULE += $(srctree)/arch/arm/kernel/module.lds endif -- cgit v1.2.3-59-g8ed1b