Hi, 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 <[email protected]> > Closes: https://github.com/KSPP/linux/issues/350 > Signed-off-by: Kees Cook <[email protected]> > --- > Cc: Marco Elver <[email protected]> > Cc: Andrey Konovalov <[email protected]> > Cc: Andrey Ryabinin <[email protected]> > Cc: Nathan Chancellor <[email protected]> > Cc: Nick Desaulniers <[email protected]> > Cc: Bill Wendling <[email protected]> > Cc: Justin Stitt <[email protected]> > Cc: [email protected] > Cc: [email protected] > Cc: [email protected] > 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/[email protected]/ > --- > 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
Clever. Acked-by: Justin Stitt <[email protected]> > +#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 > Thanks Justin
