| Message ID | 20240326164116.645718-2-aleksander.lobakin@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | compiler_types: add Endianness-dependent __counted_by_{le,be} | expand |
On 3/26/24 10:41, Alexander Lobakin wrote: > Some structures contain flexible arrays at the end and the counter for > them, but the counter has explicit Endianness and thus __counted_by() > can't be used directly. > > To increase test coverage for potential problems without breaking > anything, introduce __counted_by_{le,be}() defined depending on > platform's Endianness to either __counted_by() when applicable or noop > otherwise. > Maybe it would be a good idea to introduce such attributes on compiler > level if possible, but for now let's stop on what we have. > > Acked-by: Kees Cook <keescook@chromium.org> > Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> LGTM: Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org> Thanks -- Gustavo > --- > Documentation/conf.py | 2 ++ > scripts/kernel-doc | 1 + > include/linux/compiler_types.h | 11 +++++++++++ > 3 files changed, 14 insertions(+) > > diff --git a/Documentation/conf.py b/Documentation/conf.py > index d148f3e8dd57..0c2205d536b3 100644 > --- a/Documentation/conf.py > +++ b/Documentation/conf.py > @@ -75,6 +75,8 @@ if major >= 3: > "__rcu", > "__user", > "__force", > + "__counted_by_le", > + "__counted_by_be", > > # include/linux/compiler_attributes.h: > "__alias", > diff --git a/scripts/kernel-doc b/scripts/kernel-doc > index 967f1abb0edb..1474e95dbe4f 100755 > --- a/scripts/kernel-doc > +++ b/scripts/kernel-doc > @@ -1143,6 +1143,7 @@ sub dump_struct($$) { > $members =~ s/\s*$attribute/ /gi; > $members =~ s/\s*__aligned\s*\([^;]*\)/ /gos; > $members =~ s/\s*__counted_by\s*\([^;]*\)/ /gos; > + $members =~ s/\s*__counted_by_(le|be)\s*\([^;]*\)/ /gos; > $members =~ s/\s*__packed\s*/ /gos; > $members =~ s/\s*CRYPTO_MINALIGN_ATTR/ /gos; > $members =~ s/\s*____cacheline_aligned_in_smp/ /gos; > diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h > index 2abaa3a825a9..a29ba6ef1e27 100644 > --- a/include/linux/compiler_types.h > +++ b/include/linux/compiler_types.h > @@ -282,6 +282,17 @@ struct ftrace_likely_data { > #define __no_sanitize_or_inline __always_inline > #endif > > +/* > + * Apply __counted_by() when the Endianness matches to increase test coverage. > + */ > +#ifdef __LITTLE_ENDIAN > +#define __counted_by_le(member) __counted_by(member) > +#define __counted_by_be(member) > +#else > +#define __counted_by_le(member) > +#define __counted_by_be(member) __counted_by(member) > +#endif > + > /* Do not trap wrapping arithmetic within an annotated function. */ > #ifdef CONFIG_UBSAN_SIGNED_WRAP > # define __signed_wrap __attribute__((no_sanitize("signed-integer-overflow")))
diff --git a/Documentation/conf.py b/Documentation/conf.py index d148f3e8dd57..0c2205d536b3 100644 --- a/Documentation/conf.py +++ b/Documentation/conf.py @@ -75,6 +75,8 @@ if major >= 3: "__rcu", "__user", "__force", + "__counted_by_le", + "__counted_by_be", # include/linux/compiler_attributes.h: "__alias", diff --git a/scripts/kernel-doc b/scripts/kernel-doc index 967f1abb0edb..1474e95dbe4f 100755 --- a/scripts/kernel-doc +++ b/scripts/kernel-doc @@ -1143,6 +1143,7 @@ sub dump_struct($$) { $members =~ s/\s*$attribute/ /gi; $members =~ s/\s*__aligned\s*\([^;]*\)/ /gos; $members =~ s/\s*__counted_by\s*\([^;]*\)/ /gos; + $members =~ s/\s*__counted_by_(le|be)\s*\([^;]*\)/ /gos; $members =~ s/\s*__packed\s*/ /gos; $members =~ s/\s*CRYPTO_MINALIGN_ATTR/ /gos; $members =~ s/\s*____cacheline_aligned_in_smp/ /gos; diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h index 2abaa3a825a9..a29ba6ef1e27 100644 --- a/include/linux/compiler_types.h +++ b/include/linux/compiler_types.h @@ -282,6 +282,17 @@ struct ftrace_likely_data { #define __no_sanitize_or_inline __always_inline #endif +/* + * Apply __counted_by() when the Endianness matches to increase test coverage. + */ +#ifdef __LITTLE_ENDIAN +#define __counted_by_le(member) __counted_by(member) +#define __counted_by_be(member) +#else +#define __counted_by_le(member) +#define __counted_by_be(member) __counted_by(member) +#endif + /* Do not trap wrapping arithmetic within an annotated function. */ #ifdef CONFIG_UBSAN_SIGNED_WRAP # define __signed_wrap __attribute__((no_sanitize("signed-integer-overflow")))
Some structures contain flexible arrays at the end and the counter for them, but the counter has explicit Endianness and thus __counted_by() can't be used directly. To increase test coverage for potential problems without breaking anything, introduce __counted_by_{le,be}() defined depending on platform's Endianness to either __counted_by() when applicable or noop otherwise. Maybe it would be a good idea to introduce such attributes on compiler level if possible, but for now let's stop on what we have. Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> --- Documentation/conf.py | 2 ++ scripts/kernel-doc | 1 + include/linux/compiler_types.h | 11 +++++++++++ 3 files changed, 14 insertions(+)