| Message ID | 20220818152929.402605-5-roberto.sassu@huaweicloud.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | bpf: Add kfuncs for PKCS#7 signature verification | expand |
On Thu, Aug 18, 2022 at 05:29:23PM +0200, roberto.sassu@huaweicloud.com wrote: > From: Roberto Sassu <roberto.sassu@huawei.com> > > 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. Also, the short subject is misleading because this *just* does not move flags. > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > Reviewed-by: KP Singh <kpsingh@kernel.org> > --- > 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)) 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? BR, Jarkko
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@huaweicloud.com wrote: > > > From: Roberto Sassu <roberto.sassu@huawei.com> > > > > > > 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@huawei.com> > > > Reviewed-by: KP Singh <kpsingh@kernel.org> > > > --- > > > 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
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 + +static inline int key_lookup_flags_check(u64 flags) +{ + if (flags & ~(KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL)) + return -EINVAL; + + return 0; +} + struct seq_file; struct user_struct; struct signal_struct; diff --git a/security/keys/internal.h b/security/keys/internal.h index 9b9cf3b6fcbb..3c1e7122076b 100644 --- a/security/keys/internal.h +++ b/security/keys/internal.h @@ -165,8 +165,6 @@ extern struct key *request_key_and_link(struct key_type *type, extern bool lookup_user_key_possessed(const struct key *key, const struct key_match_data *match_data); -#define KEY_LOOKUP_CREATE 0x01 -#define KEY_LOOKUP_PARTIAL 0x02 extern long join_session_keyring(const char *name); extern void key_change_session_keyring(struct callback_head *twork);