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") Cc: Andy Lutomirski <l...@kernel.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: Ingo Molnar <mi...@redhat.com> Cc: Borislav Petkov <b...@alien8.de> Cc: x...@kernel.org Cc: "H. Peter Anvin" <h...@zytor.com> Signed-off-by: Kees Cook <keesc...@chromium.org> --- RESEND (missed lkml)... --- 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 -- 2.25.1 -- Kees Cook