| Message ID | 20220826091228.1701185-1-roberto.sassu@huaweicloud.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | None | expand |
On Fri, 2022-08-26 at 11:12 +0200, Roberto Sassu 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_valid() to check if the caller set > in the > argument only defined flags. Introduce it directly in > include/linux/key.h, > to reduce the risk that the check is not in sync with currently > defined > flags. > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > Reviewed-by: KP Singh <kpsingh@kernel.org> Jarkko, could you please ack it if it is fine? Thanks Roberto > --- > include/linux/key.h | 16 ++++++++++++++++ > security/keys/internal.h | 2 -- > 2 files changed, 16 insertions(+), 2 deletions(-) > > diff --git a/include/linux/key.h b/include/linux/key.h > index 7febc4881363..e679dbf0c940 100644 > --- a/include/linux/key.h > +++ b/include/linux/key.h > @@ -88,6 +88,22 @@ enum key_need_perm { > KEY_DEFER_PERM_CHECK, /* Special: permission check is > deferred */ > }; > > +#define KEY_LOOKUP_CREATE 0x01 > +#define KEY_LOOKUP_PARTIAL 0x02 > + > +/** > + * key_lookup_flags_valid - detect if provided key lookup flags are > valid > + * @flags: key lookup flags. > + * > + * Verify whether or not the caller set in the argument only defined > flags. > + * > + * Return: true if flags are valid, false if not. > + */ > +static inline bool key_lookup_flags_valid(u64 flags) > +{ > + return !(flags & ~(KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL)); > +} > + > 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);
On Fri, Aug 26, 2022 at 11:22:54AM +0200, Roberto Sassu wrote: > On Fri, 2022-08-26 at 11:12 +0200, Roberto Sassu 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_valid() to check if the caller set > > in the > > argument only defined flags. Introduce it directly in > > include/linux/key.h, > > to reduce the risk that the check is not in sync with currently > > defined > > flags. > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > > Reviewed-by: KP Singh <kpsingh@kernel.org> > > Jarkko, could you please ack it if it is fine? So, as said I'm not really confident that a function is even needed in the first place. It's fine if there are enough call sites to make it legit. BR, Jarkko
On Sun, Aug 28, 2022 at 06:59:41AM +0300, Jarkko Sakkinen wrote: > On Fri, Aug 26, 2022 at 11:22:54AM +0200, Roberto Sassu wrote: > > On Fri, 2022-08-26 at 11:12 +0200, Roberto Sassu 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_valid() to check if the caller set > > > in the > > > argument only defined flags. Introduce it directly in > > > include/linux/key.h, > > > to reduce the risk that the check is not in sync with currently > > > defined > > > flags. > > > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > > > Reviewed-by: KP Singh <kpsingh@kernel.org> > > > > Jarkko, could you please ack it if it is fine? > > So, as said I'm not really confident that a function is > even needed in the first place. It's fine if there are > enough call sites to make it legit. And *if* a named constant is enough, you could probably then just squash to the same patch that uses it, right? If there overwhelming amount of call sites I do fully get having a helper. BR, Jarkko
On Sun, 2022-08-28 at 07:03 +0300, Jarkko Sakkinen wrote: > On Sun, Aug 28, 2022 at 06:59:41AM +0300, Jarkko Sakkinen wrote: > > On Fri, Aug 26, 2022 at 11:22:54AM +0200, Roberto Sassu wrote: > > > On Fri, 2022-08-26 at 11:12 +0200, Roberto Sassu 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_valid() to check if the caller > > > > set > > > > in the > > > > argument only defined flags. Introduce it directly in > > > > include/linux/key.h, > > > > to reduce the risk that the check is not in sync with currently > > > > defined > > > > flags. > > > > > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > > > > Reviewed-by: KP Singh <kpsingh@kernel.org> > > > > > > Jarkko, could you please ack it if it is fine? > > > > So, as said I'm not really confident that a function is > > even needed in the first place. It's fine if there are > > enough call sites to make it legit. > > And *if* a named constant is enough, you could probably > then just squash to the same patch that uses it, right? Yes, the constant seems better. Maybe, I would add in the same patch that exports the lookup flags, since we have that. Thanks Roberto
On Mon, Aug 29, 2022 at 09:25:05AM +0200, Roberto Sassu wrote: > On Sun, 2022-08-28 at 07:03 +0300, Jarkko Sakkinen wrote: > > On Sun, Aug 28, 2022 at 06:59:41AM +0300, Jarkko Sakkinen wrote: > > > On Fri, Aug 26, 2022 at 11:22:54AM +0200, Roberto Sassu wrote: > > > > On Fri, 2022-08-26 at 11:12 +0200, Roberto Sassu 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_valid() to check if the caller > > > > > set > > > > > in the > > > > > argument only defined flags. Introduce it directly in > > > > > include/linux/key.h, > > > > > to reduce the risk that the check is not in sync with currently > > > > > defined > > > > > flags. > > > > > > > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > > > > > Reviewed-by: KP Singh <kpsingh@kernel.org> > > > > > > > > Jarkko, could you please ack it if it is fine? > > > > > > So, as said I'm not really confident that a function is > > > even needed in the first place. It's fine if there are > > > enough call sites to make it legit. > > > > And *if* a named constant is enough, you could probably > > then just squash to the same patch that uses it, right? > > Yes, the constant seems better. Maybe, I would add in the same patch > that exports the lookup flags, since we have that. Yeah, then it would be probably easier to review too since it is "in the context". BR, Jarkko
diff --git a/include/linux/key.h b/include/linux/key.h index 7febc4881363..e679dbf0c940 100644 --- a/include/linux/key.h +++ b/include/linux/key.h @@ -88,6 +88,22 @@ enum key_need_perm { KEY_DEFER_PERM_CHECK, /* Special: permission check is deferred */ }; +#define KEY_LOOKUP_CREATE 0x01 +#define KEY_LOOKUP_PARTIAL 0x02 + +/** + * key_lookup_flags_valid - detect if provided key lookup flags are valid + * @flags: key lookup flags. + * + * Verify whether or not the caller set in the argument only defined flags. + * + * Return: true if flags are valid, false if not. + */ +static inline bool key_lookup_flags_valid(u64 flags) +{ + return !(flags & ~(KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL)); +} + 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);