| Message ID | ZWj1+jkweEDWbmAR@work (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | a5e0ace04fbf56c1794b1a2fa7a93672753b3fc7 |
| Headers | show |
| Series | [next] init: Kconfig: Disable -Wstringop-overflow for GCC-11 | expand |
On Thu, Nov 30, 2023 at 02:52:10PM -0600, Gustavo A. R. Silva wrote: > -Wstringop-overflow is buggy in GCC-11. Therefore, we should disable Can you add some links for this? For example, maybe this? https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97490 Or discussions from -next builds? > this option specifically for that compiler version. To achieve this, > we introduce a new configuration option: GCC11_NO_STRINGOP_OVERFLOW. > > The compiler option related to string operation overflow is now managed > under configuration CC_STRINGOP_OVERFLOW. This option is enabled by > default for all other versions of GCC that support it. > > Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> But yeah, let's get this landed to keep new warnings from appearing... Reviewed-by: Kees Cook <keescook@chromium.org> > --- > Makefile | 4 +++- > init/Kconfig | 12 ++++++++++++ > 2 files changed, 15 insertions(+), 1 deletion(-) > > diff --git a/Makefile b/Makefile > index 2cfd71ae3a86..8adc611fb611 100644 > --- a/Makefile > +++ b/Makefile > @@ -982,7 +982,9 @@ NOSTDINC_FLAGS += -nostdinc > # perform bounds checking. > KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3) > > -KBUILD_CFLAGS += $(call cc-option, -Wstringop-overflow) > +#Currently, disable -Wstringop-overflow for GCC 11, globally. > +KBUILD_CFLAGS-$(CONFIG_CC_NO_STRINGOP_OVERFLOW) += $(call cc-option, -Wno-stringop-overflow) > +KBUILD_CFLAGS-$(CONFIG_CC_STRINGOP_OVERFLOW) += $(call cc-option, -Wstringop-overflow) > > # disable invalid "can't wrap" optimizations for signed / pointers > KBUILD_CFLAGS += -fno-strict-overflow > diff --git a/init/Kconfig b/init/Kconfig > index 9ffb103fc927..aaaa99a5d2a9 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -876,6 +876,18 @@ config CC_NO_ARRAY_BOUNDS > bool > default y if CC_IS_GCC && GCC_VERSION >= 110000 && GCC11_NO_ARRAY_BOUNDS > > +# Currently, disable -Wstringop-overflow for GCC 11, globally. > +config GCC11_NO_STRINGOP_OVERFLOW > + def_bool y > + > +config CC_NO_STRINGOP_OVERFLOW > + bool > + default y if CC_IS_GCC && GCC_VERSION >= 110000 && GCC_VERSION < 120000 && GCC11_NO_STRINGOP_OVERFLOW > + > +config CC_STRINGOP_OVERFLOW > + bool > + default y if CC_IS_GCC && !CC_NO_STRINGOP_OVERFLOW > + > # > # For architectures that know their GCC __int128 support is sound > # > -- > 2.34.1 >
On 11/30/23 15:07, Kees Cook wrote: > On Thu, Nov 30, 2023 at 02:52:10PM -0600, Gustavo A. R. Silva wrote: >> -Wstringop-overflow is buggy in GCC-11. Therefore, we should disable > > Can you add some links for this? For example, maybe this? > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97490 > > Or discussions from -next builds? Done. :) > >> this option specifically for that compiler version. To achieve this, >> we introduce a new configuration option: GCC11_NO_STRINGOP_OVERFLOW. >> >> The compiler option related to string operation overflow is now managed >> under configuration CC_STRINGOP_OVERFLOW. This option is enabled by >> default for all other versions of GCC that support it. >> >> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> > > But yeah, let's get this landed to keep new warnings from appearing... > I just applied this to my -next tree. > Reviewed-by: Kees Cook <keescook@chromium.org> Thanks! -- Gustavo
diff --git a/Makefile b/Makefile index 2cfd71ae3a86..8adc611fb611 100644 --- a/Makefile +++ b/Makefile @@ -982,7 +982,9 @@ NOSTDINC_FLAGS += -nostdinc # perform bounds checking. KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3) -KBUILD_CFLAGS += $(call cc-option, -Wstringop-overflow) +#Currently, disable -Wstringop-overflow for GCC 11, globally. +KBUILD_CFLAGS-$(CONFIG_CC_NO_STRINGOP_OVERFLOW) += $(call cc-option, -Wno-stringop-overflow) +KBUILD_CFLAGS-$(CONFIG_CC_STRINGOP_OVERFLOW) += $(call cc-option, -Wstringop-overflow) # disable invalid "can't wrap" optimizations for signed / pointers KBUILD_CFLAGS += -fno-strict-overflow diff --git a/init/Kconfig b/init/Kconfig index 9ffb103fc927..aaaa99a5d2a9 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -876,6 +876,18 @@ config CC_NO_ARRAY_BOUNDS bool default y if CC_IS_GCC && GCC_VERSION >= 110000 && GCC11_NO_ARRAY_BOUNDS +# Currently, disable -Wstringop-overflow for GCC 11, globally. +config GCC11_NO_STRINGOP_OVERFLOW + def_bool y + +config CC_NO_STRINGOP_OVERFLOW + bool + default y if CC_IS_GCC && GCC_VERSION >= 110000 && GCC_VERSION < 120000 && GCC11_NO_STRINGOP_OVERFLOW + +config CC_STRINGOP_OVERFLOW + bool + default y if CC_IS_GCC && !CC_NO_STRINGOP_OVERFLOW + # # For architectures that know their GCC __int128 support is sound #
-Wstringop-overflow is buggy in GCC-11. Therefore, we should disable this option specifically for that compiler version. To achieve this, we introduce a new configuration option: GCC11_NO_STRINGOP_OVERFLOW. The compiler option related to string operation overflow is now managed under configuration CC_STRINGOP_OVERFLOW. This option is enabled by default for all other versions of GCC that support it. Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> --- Makefile | 4 +++- init/Kconfig | 12 ++++++++++++ 2 files changed, 15 insertions(+), 1 deletion(-)