From 58ac3154b83938515129c20aa76d456a4c9202a8 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 26 Jun 2020 13:34:25 -0700 Subject: [PATCH] x86/entry: Actually disable stack protector Some builds of GCC enable stack protector by default. Simply removing the arguments is not sufficient to disable stack protector, as the stack protector for those GCC builds must be explicitly disabled. Remove the argument removals and add -fno-stack-protector. Additionally include missed x32 argument updates, and adjust whitespace for readability. Fixes: 20355e5f73a7 ("x86/entry: Exclude low level entry code from sanitizing") Signed-off-by: Kees Cook Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/202006261333.585319CA6B@keescook --- arch/x86/entry/Makefile | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/arch/x86/entry/Makefile b/arch/x86/entry/Makefile index b7a5790d8d63..08bf95dbc911 100644 --- a/arch/x86/entry/Makefile +++ b/arch/x86/entry/Makefile @@ -7,12 +7,20 @@ KASAN_SANITIZE := n UBSAN_SANITIZE := n KCOV_INSTRUMENT := n -CFLAGS_REMOVE_common.o = $(CC_FLAGS_FTRACE) -fstack-protector -fstack-protector-strong -CFLAGS_REMOVE_syscall_32.o = $(CC_FLAGS_FTRACE) -fstack-protector -fstack-protector-strong -CFLAGS_REMOVE_syscall_64.o = $(CC_FLAGS_FTRACE) -fstack-protector -fstack-protector-strong +CFLAGS_REMOVE_common.o = $(CC_FLAGS_FTRACE) +CFLAGS_REMOVE_syscall_64.o = $(CC_FLAGS_FTRACE) +CFLAGS_REMOVE_syscall_32.o = $(CC_FLAGS_FTRACE) +CFLAGS_REMOVE_syscall_x32.o = $(CC_FLAGS_FTRACE) + +CFLAGS_common.o += -fno-stack-protector +CFLAGS_syscall_64.o += -fno-stack-protector +CFLAGS_syscall_32.o += -fno-stack-protector +CFLAGS_syscall_x32.o += -fno-stack-protector CFLAGS_syscall_64.o += $(call cc-option,-Wno-override-init,) CFLAGS_syscall_32.o += $(call cc-option,-Wno-override-init,) +CFLAGS_syscall_x32.o += $(call cc-option,-Wno-override-init,) + obj-y := entry_$(BITS).o thunk_$(BITS).o syscall_$(BITS).o obj-y += common.o