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.
Discards the unused rela, plt, and got sections that are not needed in the final vmlinux, and enable orphan section warnings. Signed-off-by: Kees Cook <[email protected]> --- arch/x86/Makefile | 4 ++++ arch/x86/kernel/vmlinux.lds.S | 6 ++++++ 2 files changed, 10 insertions(+) diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 00e378de8bc0..f8a5b2333729 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -51,6 +51,10 @@ ifdef CONFIG_X86_NEED_RELOCS LDFLAGS_vmlinux := --emit-relocs --discard-none 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 += --orphan-handling=warn + # # Prevent GCC from generating any FP code by mistake. # diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index 3bfc8dd8a43d..bb085ceeaaad 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -412,6 +412,12 @@ SECTIONS DWARF_DEBUG DISCARDS + /DISCARD/ : { + *(.rela.*) *(.rela_*) + *(.rel.*) *(.rel_*) + *(.got) *(.got.*) + *(.igot.*) *(.iplt) + } } -- 2.25.1
