diff options
| -rw-r--r-- | arch/x86/Kconfig | 12 | ||||
| -rw-r--r-- | arch/x86/Makefile | 4 | ||||
| -rw-r--r-- | arch/x86/include/asm/linkage.h | 10 | ||||
| -rw-r--r-- | arch/x86/include/asm/static_call.h | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/ftrace.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/static_call.c | 5 | ||||
| -rw-r--r-- | arch/x86/lib/memmove_64.S | 2 | ||||
| -rw-r--r-- | arch/x86/lib/retpoline.S | 2 | ||||
| -rw-r--r-- | scripts/Makefile.build | 3 | ||||
| -rwxr-xr-x | scripts/link-vmlinux.sh | 3 |
10 files changed, 38 insertions, 7 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 7399327d1eff..dd13ba82ce7a 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -472,6 +472,18 @@ config RETPOLINE branches. Requires a compiler with -mindirect-branch=thunk-extern support for full protection. The kernel may run slower. +config CC_HAS_SLS + def_bool $(cc-option,-mharden-sls=all) + +config SLS + bool "Mitigate Straight-Line-Speculation" + depends on CC_HAS_SLS && X86_64 + default n + help + Compile the kernel with straight-line-speculation options to guard + against straight line speculation. The kernel image might be slightly + larger. + config X86_CPU_RESCTRL bool "x86 CPU resource control support" depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD) diff --git a/arch/x86/Makefile b/arch/x86/Makefile index c38b6577c103..e84cdd409b64 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -191,6 +191,10 @@ ifdef CONFIG_RETPOLINE endif endif +ifdef CONFIG_SLS + KBUILD_CFLAGS += -mharden-sls=all +endif + KBUILD_LDFLAGS += -m elf_$(UTS_MACHINE) ifdef CONFIG_LTO_CLANG diff --git a/arch/x86/include/asm/linkage.h b/arch/x86/include/asm/linkage.h index ebddec2f3ba8..030907922bd0 100644 --- a/arch/x86/include/asm/linkage.h +++ b/arch/x86/include/asm/linkage.h @@ -18,9 +18,19 @@ #define __ALIGN_STR __stringify(__ALIGN) #endif +#ifdef CONFIG_SLS +#define RET ret; int3 +#else +#define RET ret +#endif + #else /* __ASSEMBLY__ */ +#ifdef CONFIG_SLS +#define ASM_RET "ret; int3\n\t" +#else #define ASM_RET "ret\n\t" +#endif #endif /* __ASSEMBLY__ */ diff --git a/arch/x86/include/asm/static_call.h b/arch/x86/include/asm/static_call.h index 39ebe0511869..ed4f8bb6c2d9 100644 --- a/arch/x86/include/asm/static_call.h +++ b/arch/x86/include/asm/static_call.h @@ -36,7 +36,7 @@ __ARCH_DEFINE_STATIC_CALL_TRAMP(name, ".byte 0xe9; .long " #func " - (. + 4)") #define ARCH_DEFINE_STATIC_CALL_NULL_TRAMP(name) \ - __ARCH_DEFINE_STATIC_CALL_TRAMP(name, "ret; nop; nop; nop; nop") + __ARCH_DEFINE_STATIC_CALL_TRAMP(name, "ret; int3; nop; nop; nop") #define ARCH_ADD_TRAMP_KEY(name) \ diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index c39f906cdc4e..7cc540e6de0c 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -303,7 +303,7 @@ union ftrace_op_code_union { } __attribute__((packed)); }; -#define RET_SIZE 1 +#define RET_SIZE 1 + IS_ENABLED(CONFIG_SLS) static unsigned long create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size) diff --git a/arch/x86/kernel/static_call.c b/arch/x86/kernel/static_call.c index 9c407a33a774..531fb4cbb63f 100644 --- a/arch/x86/kernel/static_call.c +++ b/arch/x86/kernel/static_call.c @@ -17,6 +17,8 @@ enum insn_type { */ static const u8 xor5rax[] = { 0x66, 0x66, 0x48, 0x31, 0xc0 }; +static const u8 retinsn[] = { RET_INSN_OPCODE, 0xcc, 0xcc, 0xcc, 0xcc }; + static void __ref __static_call_transform(void *insn, enum insn_type type, void *func) { const void *emulate = NULL; @@ -42,8 +44,7 @@ static void __ref __static_call_transform(void *insn, enum insn_type type, void break; case RET: - code = text_gen_insn(RET_INSN_OPCODE, insn, func); - size = RET_INSN_SIZE; + code = &retinsn; break; } diff --git a/arch/x86/lib/memmove_64.S b/arch/x86/lib/memmove_64.S index e84d649620c4..50ea390df712 100644 --- a/arch/x86/lib/memmove_64.S +++ b/arch/x86/lib/memmove_64.S @@ -40,7 +40,7 @@ SYM_FUNC_START(__memmove) /* FSRM implies ERMS => no length checks, do the copy directly */ .Lmemmove_begin_forward: ALTERNATIVE "cmp $0x20, %rdx; jb 1f", "", X86_FEATURE_FSRM - ALTERNATIVE "", "movq %rdx, %rcx; rep movsb; RET", X86_FEATURE_ERMS + ALTERNATIVE "", __stringify(movq %rdx, %rcx; rep movsb; RET), X86_FEATURE_ERMS /* * movsq instruction have many startup latency diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S index a842866062c8..89b3fb244e15 100644 --- a/arch/x86/lib/retpoline.S +++ b/arch/x86/lib/retpoline.S @@ -34,7 +34,7 @@ SYM_INNER_LABEL(__x86_indirect_thunk_\reg, SYM_L_GLOBAL) ALTERNATIVE_2 __stringify(ANNOTATE_RETPOLINE_SAFE; jmp *%\reg), \ __stringify(RETPOLINE \reg), X86_FEATURE_RETPOLINE, \ - __stringify(lfence; ANNOTATE_RETPOLINE_SAFE; jmp *%\reg), X86_FEATURE_RETPOLINE_AMD + __stringify(lfence; ANNOTATE_RETPOLINE_SAFE; jmp *%\reg; int3), X86_FEATURE_RETPOLINE_AMD .endm diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 78656b527fe5..a4b89b757287 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -234,7 +234,8 @@ objtool_args = \ $(if $(CONFIG_GCOV_KERNEL)$(CONFIG_LTO_CLANG), --no-unreachable)\ $(if $(CONFIG_RETPOLINE), --retpoline) \ $(if $(CONFIG_X86_SMAP), --uaccess) \ - $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount) + $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount) \ + $(if $(CONFIG_SLS), --sls) cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool_args) $@) cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$@: $$(wildcard $(objtool))' ; } >> $(dot-target).cmd) diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 5cdd9bc5c385..9716f285e404 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -139,6 +139,9 @@ objtool_link() if [ -n "${CONFIG_X86_SMAP}" ]; then objtoolopt="${objtoolopt} --uaccess" fi + if [ -n "${CONFIG_SLS}" ]; then + objtoolopt="${objtoolopt} --sls" + fi info OBJTOOL ${1} tools/objtool/objtool ${objtoolcmd} ${objtoolopt} ${1} fi |