KEYS: Make /proc/keys check to see if a key is possessed before security check

Make /proc/keys check to see if the calling process possesses each key before
performing the security check.  The possession check can be skipped if the key
doesn't have the possessor-view permission bit set.

This causes the keys a process possesses to show up in /proc/keys, even if they
don't have matching user/group/other view permissions.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/security/keys/internal.h b/security/keys/internal.h
index 38783dcf6c6..addb67b169f 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -114,6 +114,10 @@ extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
                                     const void *description,
                                     key_match_func_t match);
 
+extern key_ref_t search_my_process_keyrings(struct key_type *type,
+                                            const void *description,
+                                            key_match_func_t match,
+                                            const struct cred *cred);
 extern key_ref_t search_process_keyrings(struct key_type *type,
                                          const void *description,
                                          key_match_func_t match,
@@ -134,6 +138,7 @@ extern struct key *request_key_and_link(struct key_type *type,
                                         struct key *dest_keyring,
                                         unsigned long flags);
 
+extern int lookup_user_key_possessed(const struct key *key, const void *target);
 extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags,
                                  key_perm_t perm);
 #define KEY_LOOKUP_CREATE       0x01