Messages in this thread Patch in this message | | | From | Yu-cheng Yu <> | Subject | [PATCH v25 6/9] x86/vdso: Insert endbr32/endbr64 to vDSO | Date | Thu, 15 Apr 2021 15:17:31 -0700 |
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From: "H.J. Lu" <hjl.tools@gmail.com>
When Indirect Branch Tracking (IBT) is enabled, vDSO functions may be called indirectly, and must have ENDBR32 or ENDBR64 as the first instruction. The compiler must support -fcf-protection=branch so that it can be used to compile vDSO.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com> Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Kees Cook <keescook@chromium.org> --- v24: - Replace CONFIG_X86_CET with CONFIG_X86_IBT to reflect splitting of shadow stack and ibt.
arch/x86/entry/vdso/Makefile | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index 05c4abc2fdfd..a773a5f03b63 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -93,6 +93,10 @@ endif $(vobjs): KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO) $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) +ifdef CONFIG_X86_IBT +$(vobjs) $(vobjs32): KBUILD_CFLAGS += -fcf-protection=branch +endif + # # vDSO code runs in userspace and -pg doesn't help with profiling anyway. # -- 2.21.0
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