Re: [PATCH v5 06/21] modpost: clean up is_executable_section()

Masahiro Yamada
2023-05-20T13:20:36Z

On Thu, May 18, 2023 at 6:10 AM Nick Desaulniers
<ndesaulniers@google.com> wrote:
>
> On Sun, May 14, 2023 at 8:28 AM Masahiro Yamada <masahiroy@kernel.org> wrote:
> >
> > SHF_EXECINSTR is a bit flag (#define SHF_EXECINSTR 0x4).
> > Compare the masked flag to '!= 0'.
> >
> > There is no good reason to stop modpost immediately even if a special
> > section index is given. You will get a section mismatch error anyway.
> >
> > Also, change the return type to bool.
> >
> > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
>
> Moving the definition and renaming the parameter seems very
> unnecessary, but whatever. Thanks for the patch!

Moving the definition _is_ necessary.

See the next patch, which moves the call-site of
is_executable_section().

The definition must come before the caller.

The current code exceeds 80-cols per line.

I renamed the parameters so that the lines
fit within 80-cols without wrapping.

> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
>
> > ---
> >
> > scripts/mod/modpost.c | 16 ++++++++--------
> > 1 file changed, 8 insertions(+), 8 deletions(-)
> >
> > diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
> > index bb7d1d87bae7..0bda2f22c985 100644
> > --- a/scripts/mod/modpost.c
> > +++ b/scripts/mod/modpost.c
> > @@ -1207,6 +1207,14 @@ static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
> > return near;
> > }
> >
> > +static bool is_executable_section(struct elf_info *elf, unsigned int secndx)
> > +{
> > + if (secndx > elf->num_sections)
> > + return false;
> > +
> > + return (elf->sechdrs[secndx].sh_flags & SHF_EXECINSTR) != 0;
> > +}
> > +
> > static void default_mismatch_handler(const char *modname, struct elf_info *elf,
> > const struct sectioncheck* const mismatch,
> > Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
> > @@ -1252,14 +1260,6 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf,
> > }
> > }
> >
> > -static int is_executable_section(struct elf_info* elf, unsigned int section_index)
> > -{
> > - if (section_index > elf->num_sections)
> > - fatal("section_index is outside elf->num_sections!\n");
> > -
> > - return ((elf->sechdrs[section_index].sh_flags & SHF_EXECINSTR) == SHF_EXECINSTR);
> > -}
> > -
> > static void extable_mismatch_handler(const char* modname, struct elf_info *elf,
> > const struct sectioncheck* const mismatch,
> > Elf_Rela* r, Elf_Sym* sym,
> > --
> > 2.39.2
> >
>
>
> --
> Thanks,
> ~Nick Desaulniers

--
Best Regards
Masahiro Yamada