From: Peter Zijlstra <peterz@xxxxxxxxxxxxx> commit d08965a27e84ca090b504844d50c24fc98587b11 upstream. UBSAN can insert extra code in random locations; including AC=1 sections. Typically this code is not safe and needs wrapping. So far, only __ubsan_handle_type_mismatch* have been observed in AC=1 sections and therefore only those are annotated. Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> [stable backport: only take the lib/Makefile change to resolve gcc-10 build issues] Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- lib/Makefile | 1 + 1 file changed, 1 insertion(+) --- a/lib/Makefile +++ b/lib/Makefile @@ -269,6 +269,7 @@ obj-$(CONFIG_UCS2_STRING) += ucs2_string obj-$(CONFIG_UBSAN) += ubsan.o UBSAN_SANITIZE_ubsan.o := n +CFLAGS_ubsan.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) obj-$(CONFIG_SBITMAP) += sbitmap.o