On Wed, Apr 24, 2024 at 03:40:29PM -0700, Kees Cook wrote: > When generating Runtime Calls, Clang doesn't respect the -mregparm=3 > option used on i386. Hopefully this will be fixed correctly in Clang 19: > https://github.com/llvm/llvm-project/pull/89707 > but we need to fix this for earlier Clang versions today. Force the > calling convention to use non-register arguments. > > Reported-by: Erhard Furtner <erhar...@mailbox.org> > Closes: https://github.com/KSPP/linux/issues/350 > Signed-off-by: Kees Cook <keesc...@chromium.org>
Acked-by: Nathan Chancellor <nat...@kernel.org> > --- > Cc: Marco Elver <el...@google.com> > Cc: Andrey Konovalov <andreyk...@gmail.com> > Cc: Andrey Ryabinin <ryabinin....@gmail.com> > Cc: Nathan Chancellor <nat...@kernel.org> > Cc: Nick Desaulniers <ndesaulni...@google.com> > Cc: Bill Wendling <mo...@google.com> > Cc: Justin Stitt <justinst...@google.com> > Cc: l...@lists.linux.dev > Cc: kasan-...@googlegroups.com > Cc: linux-hardening@vger.kernel.org > v2: > - use email address in Reported-by > - link to upstream llvm bug in ubsan.h comment > - drop needless /**/ > - explicitly test Clang version > v1: https://lore.kernel.org/lkml/20240424162942.work.341-k...@kernel.org/ > --- > lib/ubsan.h | 41 +++++++++++++++++++++++++++-------------- > 1 file changed, 27 insertions(+), 14 deletions(-) > > diff --git a/lib/ubsan.h b/lib/ubsan.h > index 50ef50811b7c..07e37d4429b4 100644 > --- a/lib/ubsan.h > +++ b/lib/ubsan.h > @@ -124,19 +124,32 @@ typedef s64 s_max; > typedef u64 u_max; > #endif > > -void __ubsan_handle_add_overflow(void *data, void *lhs, void *rhs); > -void __ubsan_handle_sub_overflow(void *data, void *lhs, void *rhs); > -void __ubsan_handle_mul_overflow(void *data, void *lhs, void *rhs); > -void __ubsan_handle_negate_overflow(void *_data, void *old_val); > -void __ubsan_handle_divrem_overflow(void *_data, void *lhs, void *rhs); > -void __ubsan_handle_type_mismatch(struct type_mismatch_data *data, void > *ptr); > -void __ubsan_handle_type_mismatch_v1(void *_data, void *ptr); > -void __ubsan_handle_out_of_bounds(void *_data, void *index); > -void __ubsan_handle_shift_out_of_bounds(void *_data, void *lhs, void *rhs); > -void __ubsan_handle_builtin_unreachable(void *_data); > -void __ubsan_handle_load_invalid_value(void *_data, void *val); > -void __ubsan_handle_alignment_assumption(void *_data, unsigned long ptr, > - unsigned long align, > - unsigned long offset); > +/* > + * When generating Runtime Calls, Clang doesn't respect the -mregparm=3 > + * option used on i386: https://github.com/llvm/llvm-project/issues/89670 > + * Fix this for earlier Clang versions by forcing the calling convention > + * to use non-register arguments. > + */ > +#if defined(CONFIG_X86_32) && \ > + defined(CONFIG_CC_IS_CLANG) && CONFIG_CLANG_VERSION < 190000 > +# define ubsan_linkage asmlinkage > +#else > +# define ubsan_linkage > +#endif > + > +void ubsan_linkage __ubsan_handle_add_overflow(void *data, void *lhs, void > *rhs); > +void ubsan_linkage __ubsan_handle_sub_overflow(void *data, void *lhs, void > *rhs); > +void ubsan_linkage __ubsan_handle_mul_overflow(void *data, void *lhs, void > *rhs); > +void ubsan_linkage __ubsan_handle_negate_overflow(void *_data, void > *old_val); > +void ubsan_linkage __ubsan_handle_divrem_overflow(void *_data, void *lhs, > void *rhs); > +void ubsan_linkage __ubsan_handle_type_mismatch(struct type_mismatch_data > *data, void *ptr); > +void ubsan_linkage __ubsan_handle_type_mismatch_v1(void *_data, void *ptr); > +void ubsan_linkage __ubsan_handle_out_of_bounds(void *_data, void *index); > +void ubsan_linkage __ubsan_handle_shift_out_of_bounds(void *_data, void > *lhs, void *rhs); > +void ubsan_linkage __ubsan_handle_builtin_unreachable(void *_data); > +void ubsan_linkage __ubsan_handle_load_invalid_value(void *_data, void *val); > +void ubsan_linkage __ubsan_handle_alignment_assumption(void *_data, unsigned > long ptr, > + unsigned long align, > + unsigned long offset); > > #endif > -- > 2.34.1 >
