v3: - merge series back together (I tried to make it separable, but no luck) - remove unwanted sections in libstub - remove unwanted .eh_frame sections for both .c and .S - handle sections seen during allnoconfig builds - handle synthetic and double-quoted sections reported by Clang - add reviewed-bys v2: https://lore.kernel.org/lkml/20200622205815.2988115-1-keescook@xxxxxxxxxxxx/ v1: https://lore.kernel.org/lkml/20200228002244.15240-1-keescook@xxxxxxxxxxxx/ A recent bug[1] was solved for builds linked with ld.lld, and tracking it down took way longer than it needed to (a year). Ultimately, it boiled down to differences between ld.bfd and ld.lld's handling of orphan sections. Similarly, the recent FGKASLR series brough up orphan section handling too[2]. In both cases, it would have been nice if the linker was running with --orphan-handling=warn so that surprise sections wouldn't silently get mapped into the kernel image at locations up to the whim of the linker's orphan handling logic. Instead, all desired sections should be explicitly identified in the linker script (to be either kept or discarded) with any orphans throwing a warning. The powerpc architecture actually already does this, so this series extends coverage to x86, arm, and arm64. All three architectures depend on the first two commits (to vmlinux.lds.h), and x86 and arm64 depend on the third patch (to libstub). As such, I'd like to land this series as a whole. Given that two thirds of it is in the arm universe, perhaps this can land via the arm64 tree? If x86 -tip is preferred, that works too. Or I could just carry this myself in -next. In all cases, I would really appreciate reviews/acks/etc. :) Thanks! -Kees This series is here: https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git/log/?h=linker/orphans/warn/v3 [1] https://github.com/ClangBuiltLinux/linux/issues/282 [2] https://lore.kernel.org/lkml/202002242122.AA4D1B8@keescook/ Kees Cook (9): vmlinux.lds.h: Add .gnu.version* to DISCARDS vmlinux.lds.h: Add .symtab, .strtab, and .shstrtab to STABS_DEBUG efi/libstub: Remove .note.gnu.property x86/build: Warn on orphan section placement x86/boot: Warn on orphan section placement arm/build: Warn on orphan section placement arm/boot: Warn on orphan section placement arm64/build: Use common DISCARDS in linker script arm64/build: Warn on orphan section placement arch/arm/Makefile | 4 ++++ arch/arm/boot/compressed/Makefile | 2 ++ arch/arm/boot/compressed/vmlinux.lds.S | 17 ++++++-------- .../arm/{kernel => include/asm}/vmlinux.lds.h | 22 ++++++++++++++----- arch/arm/kernel/vmlinux-xip.lds.S | 5 ++--- arch/arm/kernel/vmlinux.lds.S | 5 ++--- arch/arm64/Makefile | 9 +++++++- arch/arm64/kernel/smccc-call.S | 2 -- arch/arm64/kernel/vmlinux.lds.S | 16 ++++++++++---- arch/arm64/mm/mmu.c | 2 +- arch/x86/Makefile | 4 ++++ arch/x86/boot/compressed/Makefile | 3 ++- arch/x86/boot/compressed/vmlinux.lds.S | 11 ++++++++++ arch/x86/include/asm/asm.h | 6 ++++- arch/x86/kernel/vmlinux.lds.S | 6 +++++ drivers/firmware/efi/libstub/Makefile | 3 +++ include/asm-generic/vmlinux.lds.h | 7 +++++- 17 files changed, 92 insertions(+), 32 deletions(-) rename arch/arm/{kernel => include/asm}/vmlinux.lds.h (92%) -- 2.25.1
