The following commit has been merged into the core/build branch of tip: Commit-ID: d1c0272bc1c068f8c2cb3d1b395173602b0df6e7 Gitweb: https://git.kernel.org/tip/d1c0272bc1c068f8c2cb3d1b395173602b0df6e7 Author: Kees Cook <keesc...@chromium.org> AuthorDate: Fri, 21 Aug 2020 12:43:08 -07:00 Committer: Ingo Molnar <mi...@kernel.org> CommitterDate: Tue, 01 Sep 2020 10:03:18 +02:00
x86/boot/compressed: Remove, discard, or assert for unwanted sections In preparation for warning on orphan sections, stop the linker from generating the .eh_frame* sections, discard unwanted non-zero-sized generated sections, and enforce other expected-to-be-zero-sized sections (since discarding them might hide problems with them suddenly gaining unexpected entries). Signed-off-by: Kees Cook <keesc...@chromium.org> Signed-off-by: Ingo Molnar <mi...@kernel.org> Link: https://lore.kernel.org/r/20200821194310.3089815-28-keesc...@chromium.org --- arch/x86/boot/compressed/Makefile | 1 + arch/x86/boot/compressed/vmlinux.lds.S | 14 ++++++++++++-- 2 files changed, 13 insertions(+), 2 deletions(-) diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 753d572..5b7f6e1 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -50,6 +50,7 @@ GCOV_PROFILE := n UBSAN_SANITIZE :=n KBUILD_LDFLAGS := -m elf_$(UTS_MACHINE) +KBUILD_LDFLAGS += $(call ld-option,--no-ld-generated-unwind-info) # Compressed kernel should be built as PIE since it may be loaded at any # address by the bootloader. LDFLAGS_vmlinux := -pie $(call ld-option, --no-dynamic-linker) diff --git a/arch/x86/boot/compressed/vmlinux.lds.S b/arch/x86/boot/compressed/vmlinux.lds.S index ca544a1..02f6feb 100644 --- a/arch/x86/boot/compressed/vmlinux.lds.S +++ b/arch/x86/boot/compressed/vmlinux.lds.S @@ -72,6 +72,11 @@ SECTIONS ELF_DETAILS DISCARDS + /DISCARD/ : { + *(.dynamic) *(.dynsym) *(.dynstr) *(.dynbss) + *(.hash) *(.gnu.hash) + *(.note.*) + } .got.plt (INFO) : { *(.got.plt) @@ -93,13 +98,18 @@ SECTIONS } ASSERT(SIZEOF(.got) == 0, "Unexpected GOT entries detected!") + .plt : { + *(.plt) *(.plt.*) + } + ASSERT(SIZEOF(.plt) == 0, "Unexpected run-time procedure linkages detected!") + .rel.dyn : { - *(.rel.*) + *(.rel.*) *(.rel_*) } ASSERT(SIZEOF(.rel.dyn) == 0, "Unexpected run-time relocations (.rel) detected!") .rela.dyn : { - *(.rela.*) + *(.rela.*) *(.rela_*) } ASSERT(SIZEOF(.rela.dyn) == 0, "Unexpected run-time relocations (.rela) detected!") }
