KEYS: Deal with dead-type keys appropriately [try #6]
Allow keys for which the key type has been removed to be unlinked. Currently
dead-type keys can only be disposed of by completely clearing the keyrings
that point to them.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index ed929af..4739cfb 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -487,7 +487,7 @@
* - don't create special keyrings unless so requested
* - partially constructed keys aren't found unless requested
*/
-key_ref_t lookup_user_key(key_serial_t id, int create, int partial,
+key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
key_perm_t perm)
{
struct request_key_auth *rka;
@@ -503,7 +503,7 @@
switch (id) {
case KEY_SPEC_THREAD_KEYRING:
if (!cred->thread_keyring) {
- if (!create)
+ if (!(lflags & KEY_LOOKUP_CREATE))
goto error;
ret = install_thread_keyring();
@@ -521,7 +521,7 @@
case KEY_SPEC_PROCESS_KEYRING:
if (!cred->tgcred->process_keyring) {
- if (!create)
+ if (!(lflags & KEY_LOOKUP_CREATE))
goto error;
ret = install_process_keyring();
@@ -642,7 +642,14 @@
break;
}
- if (!partial) {
+ /* unlink does not use the nominated key in any way, so can skip all
+ * the permission checks as it is only concerned with the keyring */
+ if (lflags & KEY_LOOKUP_FOR_UNLINK) {
+ ret = 0;
+ goto error;
+ }
+
+ if (!(lflags & KEY_LOOKUP_PARTIAL)) {
ret = wait_for_key_construction(key, true);
switch (ret) {
case -ERESTARTSYS:
@@ -660,7 +667,8 @@
}
ret = -EIO;
- if (!partial && !test_bit(KEY_FLAG_INSTANTIATED, &key->flags))
+ if (!(lflags & KEY_LOOKUP_PARTIAL) &&
+ !test_bit(KEY_FLAG_INSTANTIATED, &key->flags))
goto invalid_key;
/* check the permissions */