Re: [PATCH bpf-next v3 14/15] bpf: allow '?' at the beginning of DATASEC names

[Eduard Zingerman <eddyz87@gmail.com>]

On Tue, 2024-03-05 at 13:43 -0800, Andrii Nakryiko wrote:
[...]

> > @@ -761,12 +761,13 @@ static bool btf_name_offset_valid(const struct btf *btf, u32 offset)
> >         return offset < btf->hdr.str_len;
> >  }
> > 
> > -static bool __btf_name_char_ok(char c, bool first)
> > +static bool __btf_name_char_ok(char c, bool first, bool allow_qmark)
> >  {
> >         if ((first ? !isalpha(c) :
> >                      !isalnum(c)) &&
> >             c != '_' &&
> > -           c != '.')
> > +           c != '.' &&
> > +           (allow_qmark && first ? c != '?' : true))
> 
> ELF data section can have pretty much arbitrary characters in the
> name. I don't think we should allow question mark only at the
> beginning. Let's just allow any printable character, anywhere (for
> DATASEC only, of course)? There is no danger in doing this, data
> section name is not a variable name or some C identifier, and so won't
> be used like that.

Makes sense to me.

Thank you for reviewing this patch-set, I've applied the changes,
will share v4 tomorrow.