From: Kees Cook <keescook@chromium.org> To: Will Deacon <will@kernel.org> Cc: Kees Cook <keescook@chromium.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 Subject: [PATCH v4 17/17] x86/boot: Warn on orphan section placement Date: Sun, 28 Jun 2020 23:18:40 -0700 [thread overview] Message-ID: <20200629061840.4065483-18-keescook@chromium.org> (raw) In-Reply-To: <20200629061840.4065483-1-keescook@chromium.org> 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. Add the common debugging sections. Discard the unused note, rel, plt, dyn, and hash sections that are not needed in the compressed vmlinux. Disable .eh_frame generation in the linker and enable orphan section warnings. Signed-off-by: Kees Cook <keescook@chromium.org> --- arch/x86/boot/compressed/Makefile | 3 ++- arch/x86/boot/compressed/vmlinux.lds.S | 10 ++++++++++ 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 7619742f91c9..646720a05f89 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -48,6 +48,7 @@ GCOV_PROFILE := n UBSAN_SANITIZE :=n KBUILD_LDFLAGS := -m elf_$(UTS_MACHINE) +KBUILD_LDFLAGS += $(call ld-option,--no-ld-generated-unwind-info) # Compressed kernel should be built as PIE since it may be loaded at any # address by the bootloader. ifeq ($(CONFIG_X86_32),y) @@ -59,7 +60,7 @@ else KBUILD_LDFLAGS += $(shell $(LD) --help 2>&1 | grep -q "\-z noreloc-overflow" \ && echo "-z noreloc-overflow -pie --no-dynamic-linker") endif -LDFLAGS_vmlinux := -T +LDFLAGS_vmlinux := --orphan-handling=warn -T hostprogs := mkpiggy HOST_EXTRACFLAGS += -I$(srctree)/tools/include diff --git a/arch/x86/boot/compressed/vmlinux.lds.S b/arch/x86/boot/compressed/vmlinux.lds.S index d88612e3091f..9afb8737896f 100644 --- a/arch/x86/boot/compressed/vmlinux.lds.S +++ b/arch/x86/boot/compressed/vmlinux.lds.S @@ -75,7 +75,17 @@ SECTIONS . = ALIGN(PAGE_SIZE); /* keep ZO size page aligned */ _end = .; + STABS_DEBUG + DWARF_DEBUG ELF_DETAILS DISCARDS + /DISCARD/ : { + *(.note.*) + *(.rela.*) *(.rela_*) + *(.rel.*) *(.rel_*) + *(.plt) *(.plt.*) + *(.dyn*) + *(.hash) *(.gnu.hash) + } } -- 2.25.1
WARNING: multiple messages have this Message-ID (diff)
From: Kees Cook <keescook@chromium.org> To: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com>, linux-arch@vger.kernel.org, linux-efi@vger.kernel.org, Kees Cook <keescook@chromium.org>, Arnd Bergmann <arnd@arndb.de>, Catalin Marinas <catalin.marinas@arm.com>, Masahiro Yamada <masahiroy@kernel.org>, x86@kernel.org, Nick Desaulniers <ndesaulniers@google.com>, Russell King <linux@armlinux.org.uk>, linux-kernel@vger.kernel.org, Nathan Chancellor <natechancellor@gmail.com>, clang-built-linux@googlegroups.com, Arvind Sankar <nivedita@alum.mit.edu>, Ingo Molnar <mingo@redhat.com>, James Morse <james.morse@arm.com>, Thomas Gleixner <tglx@linutronix.de>, Borislav Petkov <bp@suse.de>, Peter Collingbourne <pcc@google.com>, Ard Biesheuvel <ardb@kernel.org>, linux-arm-kernel@lists.infradead.org Subject: [PATCH v4 17/17] x86/boot: Warn on orphan section placement Date: Sun, 28 Jun 2020 23:18:40 -0700 [thread overview] Message-ID: <20200629061840.4065483-18-keescook@chromium.org> (raw) In-Reply-To: <20200629061840.4065483-1-keescook@chromium.org> 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. Add the common debugging sections. Discard the unused note, rel, plt, dyn, and hash sections that are not needed in the compressed vmlinux. Disable .eh_frame generation in the linker and enable orphan section warnings. Signed-off-by: Kees Cook <keescook@chromium.org> --- arch/x86/boot/compressed/Makefile | 3 ++- arch/x86/boot/compressed/vmlinux.lds.S | 10 ++++++++++ 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 7619742f91c9..646720a05f89 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -48,6 +48,7 @@ GCOV_PROFILE := n UBSAN_SANITIZE :=n KBUILD_LDFLAGS := -m elf_$(UTS_MACHINE) +KBUILD_LDFLAGS += $(call ld-option,--no-ld-generated-unwind-info) # Compressed kernel should be built as PIE since it may be loaded at any # address by the bootloader. ifeq ($(CONFIG_X86_32),y) @@ -59,7 +60,7 @@ else KBUILD_LDFLAGS += $(shell $(LD) --help 2>&1 | grep -q "\-z noreloc-overflow" \ && echo "-z noreloc-overflow -pie --no-dynamic-linker") endif -LDFLAGS_vmlinux := -T +LDFLAGS_vmlinux := --orphan-handling=warn -T hostprogs := mkpiggy HOST_EXTRACFLAGS += -I$(srctree)/tools/include diff --git a/arch/x86/boot/compressed/vmlinux.lds.S b/arch/x86/boot/compressed/vmlinux.lds.S index d88612e3091f..9afb8737896f 100644 --- a/arch/x86/boot/compressed/vmlinux.lds.S +++ b/arch/x86/boot/compressed/vmlinux.lds.S @@ -75,7 +75,17 @@ SECTIONS . = ALIGN(PAGE_SIZE); /* keep ZO size page aligned */ _end = .; + STABS_DEBUG + DWARF_DEBUG ELF_DETAILS DISCARDS + /DISCARD/ : { + *(.note.*) + *(.rela.*) *(.rela_*) + *(.rel.*) *(.rel_*) + *(.plt) *(.plt.*) + *(.dyn*) + *(.hash) *(.gnu.hash) + } } -- 2.25.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2020-06-29 19:13 UTC|newest] Thread overview: 94+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-06-29 6:18 [PATCH v4 00/17] Warn on orphan section placement Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 01/17] vmlinux.lds.h: Add .gnu.version* to DISCARDS Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 02/17] vmlinux.lds.h: Avoid KASAN and KCSAN's unwanted sections Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 03/17] vmlinux.lds.h: Split ELF_DETAILS from STABS_DEBUG Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 04/17] vmlinux.lds.h: Add .symtab, .strtab, and .shstrtab to ELF_DETAILS Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 05/17] ctype: Work around Clang -mbranch-protection=none bug Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 8:15 ` Ard Biesheuvel 2020-06-29 8:15 ` Ard Biesheuvel 2020-06-29 8:15 ` Ard Biesheuvel 2020-06-29 14:43 ` Kees Cook 2020-06-29 14:43 ` Kees Cook 2020-06-29 14:43 ` Kees Cook 2020-06-29 15:06 ` Kees Cook 2020-06-29 15:06 ` Kees Cook 2020-06-29 15:06 ` Kees Cook 2020-06-29 15:08 ` Ard Biesheuvel 2020-06-29 15:08 ` Ard Biesheuvel 2020-06-29 15:08 ` Ard Biesheuvel 2020-06-29 15:16 ` Kees Cook 2020-06-29 15:16 ` Kees Cook 2020-06-29 15:16 ` Kees Cook 2020-06-29 18:02 ` Nick Desaulniers 2020-06-29 18:02 ` Nick Desaulniers 2020-06-29 18:02 ` Nick Desaulniers 2020-06-29 18:37 ` Kees Cook 2020-06-29 18:37 ` Kees Cook 2020-06-29 18:37 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 06/17] efi/libstub: Disable -mbranch-protection Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 07/17] arm64/build: Use common DISCARDS in linker script Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 08/17] arm64/mm: Remove needless section quotes Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 19:53 ` Nick Desaulniers 2020-06-29 19:53 ` Nick Desaulniers 2020-06-29 19:53 ` Nick Desaulniers 2020-06-29 20:03 ` Joe Perches 2020-06-29 20:03 ` Joe Perches 2020-06-29 20:03 ` Joe Perches 2020-06-29 20:29 ` Nick Desaulniers 2020-06-29 20:29 ` Nick Desaulniers 2020-06-29 20:29 ` Nick Desaulniers 2020-06-29 20:04 ` Kees Cook 2020-06-29 20:04 ` Kees Cook 2020-06-29 20:04 ` Kees Cook 2020-06-29 20:54 ` Arvind Sankar 2020-06-29 20:54 ` Arvind Sankar 2020-06-29 20:54 ` Arvind Sankar 2020-06-29 21:06 ` Arvind Sankar 2020-06-29 21:06 ` Arvind Sankar 2020-06-29 21:06 ` Arvind Sankar 2020-06-29 6:18 ` [PATCH v4 09/17] arm64/build: Remove .eh_frame* sections due to unwind tables Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 10/17] arm64/kernel: Remove needless Call Frame Information annotations Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 11/17] arm64/build: Warn on orphan section placement Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 12/17] arm/build: Refactor linker script headers Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 13/17] arm/build: Explicitly keep .ARM.attributes sections Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 14/17] arm/build: Warn on orphan section placement Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 15:54 ` Arvind Sankar 2020-06-29 15:54 ` Arvind Sankar 2020-06-29 18:07 ` Russell King - ARM Linux admin 2020-06-29 18:07 ` Russell King - ARM Linux admin 2020-06-29 18:15 ` Arvind Sankar 2020-06-29 18:15 ` Arvind Sankar 2020-06-29 19:03 ` Russell King - ARM Linux admin 2020-06-29 19:03 ` Russell King - ARM Linux admin 2020-06-29 19:47 ` Nick Desaulniers 2020-06-29 19:47 ` Nick Desaulniers 2020-06-29 19:47 ` Nick Desaulniers 2020-06-29 6:18 ` [PATCH v4 15/17] arm/boot: " Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` [PATCH v4 16/17] x86/build: " Kees Cook 2020-06-29 6:18 ` Kees Cook 2020-06-29 6:18 ` Kees Cook [this message] 2020-06-29 6:18 ` [PATCH v4 17/17] x86/boot: " Kees Cook 2020-08-21 16:02 ` [PATCH v4 00/17] " Will Deacon 2020-08-21 16:02 ` Will Deacon 2020-08-21 17:36 ` Kees Cook 2020-08-21 17:36 ` Kees Cook
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