On Fri, Aug 26, 2022 at 09:14:09AM +0200, Roberto Sassu wrote: > On Fri, 2022-08-26 at 08:42 +0300, Jarkko Sakkinen wrote: > > On Thu, Aug 18, 2022 at 05:29:23PM +0200, > > roberto.sassu@xxxxxxxxxxxxxxx wrote: > > > From: Roberto Sassu <roberto.sassu@xxxxxxxxxx> > > > > > > In preparation for the patch that introduces the > > > bpf_lookup_user_key() eBPF > > > kfunc, move KEY_LOOKUP_ definitions to include/linux/key.h, to be > > > able to > > > validate the kfunc parameters. > > > > > > Also, introduce key_lookup_flags_check() directly in > > > include/linux/key.h, > > > to reduce the risk that the check is not in sync with currently > > > defined > > > flags. > > > > Missing the description what the heck this function even is. > > > > Please, explain that. > > Hi Jarkko > > sorry, forgot to update the commit description. Will do it. > > > Also, the short subject is misleading because this *just* > > does not move flags. > > > > > Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx> > > > Reviewed-by: KP Singh <kpsingh@xxxxxxxxxx> > > > --- > > > include/linux/key.h | 11 +++++++++++ > > > security/keys/internal.h | 2 -- > > > 2 files changed, 11 insertions(+), 2 deletions(-) > > > > > > diff --git a/include/linux/key.h b/include/linux/key.h > > > index 7febc4881363..b5bbae77a9e7 100644 > > > --- a/include/linux/key.h > > > +++ b/include/linux/key.h > > > @@ -88,6 +88,17 @@ enum key_need_perm { > > > KEY_DEFER_PERM_CHECK, /* Special: permission check is > > > deferred */ > > > }; > > > > > > +#define KEY_LOOKUP_CREATE 0x01 > > > +#define KEY_LOOKUP_PARTIAL 0x02 > > > + > > > > /* > > * Explain what the heck this function is. > > */ > > > +static inline int key_lookup_flags_check(u64 flags) > > > +{ > > > + if (flags & ~(KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL)) > > > + return -EINVAL; > > > + > > > + return 0; > > > +} > > > > This is essentially a boolean function, right? > > > > I.e. the implementation can be just: > > > > !!(flags & ~(KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL)) > > Absolutely fine with that, if you prefer. It can be either, it more depends on if a new function is needed in the first place. E.g. if you are worried about maintaining you could just as well define a constant containing the mask, right? > > > Not even sure if this is needed in the first place, or > > would it be better just to open code it. How many call > > sites does it have anyway? > > > > Daniel preferred to have this check here. How many call sites? BR, Jarkko