On Mon, Apr 15, 2024 at 11:28:35AM -0700, Kees Cook wrote: > On arm64, UBSAN traps can be decoded from the trap instruction. Add the > add, sub, and mul overflow trap codes now that CONFIG_UBSAN_SIGNED_WRAP > exists. Seen under clang 19: > > Internal error: UBSAN: unrecognized failure code: 00000000f2005515 [#1] > PREEMPT SMP > > Reported-by: Nathan Chancellor <nat...@kernel.org> > Closes: > https://lore.kernel.org/lkml/20240411-fix-ubsan-in-hardening-config-v1-0-e0177c80f...@kernel.org > Fixes: 557f8c582a9b ("ubsan: Reintroduce signed overflow sanitizer") > Signed-off-by: Kees Cook <keesc...@chromium.org>
As I mentioned, CONFIG_UBSAN_SIGNED_INTEGER_WRAP needs to be CONFIG_UBSAN_SIGNED_WRAP. I applied this change with that fix up and the warning now becomes: Internal error: UBSAN: integer subtraction overflow: 00000000f2005515 [#1] PREEMPT SMP So: Tested-by: Nathan Chancellor <nat...@kernel.org> > --- > Cc: Marco Elver <el...@google.com> > Cc: Justin Stitt <justinst...@google.com> > Cc: Andrey Konovalov <andreyk...@gmail.com> > Cc: Andrey Ryabinin <ryabinin....@gmail.com> > Cc: Andrew Morton <a...@linux-foundation.org> > Cc: kasan-...@googlegroups.com > Cc: linux-hardening@vger.kernel.org > --- > lib/ubsan.c | 18 ++++++++++++++++-- > 1 file changed, 16 insertions(+), 2 deletions(-) > > diff --git a/lib/ubsan.c b/lib/ubsan.c > index 5fc107f61934..ad32beb8c058 100644 > --- a/lib/ubsan.c > +++ b/lib/ubsan.c > @@ -44,9 +44,10 @@ const char *report_ubsan_failure(struct pt_regs *regs, u32 > check_type) > case ubsan_shift_out_of_bounds: > return "UBSAN: shift out of bounds"; > #endif > -#ifdef CONFIG_UBSAN_DIV_ZERO > +#if defined(CONFIG_UBSAN_DIV_ZERO) || > defined(CONFIG_UBSAN_SIGNED_INTEGER_WRAP) > /* > - * SanitizerKind::IntegerDivideByZero emits > + * SanitizerKind::IntegerDivideByZero and > + * SanitizerKind::SignedIntegerOverflow emit > * SanitizerHandler::DivremOverflow. > */ > case ubsan_divrem_overflow: > @@ -77,6 +78,19 @@ const char *report_ubsan_failure(struct pt_regs *regs, u32 > check_type) > return "UBSAN: alignment assumption"; > case ubsan_type_mismatch: > return "UBSAN: type mismatch"; > +#endif > +#ifdef CONFIG_UBSAN_SIGNED_INTEGER_WRAP > + /* > + * SanitizerKind::SignedIntegerOverflow emits > + * SanitizerHandler::AddOverflow, SanitizerHandler::SubOverflow, > + * or SanitizerHandler::MulOverflow. > + */ > + case ubsan_add_overflow: > + return "UBSAN: integer addition overflow"; > + case ubsan_sub_overflow: > + return "UBSAN: integer subtraction overflow"; > + case ubsan_mul_overflow: > + return "UBSAN: integer multiplication overflow"; > #endif > default: > return "UBSAN: unrecognized failure code"; > -- > 2.34.1 >
