1 files changed, 52 insertions, 0 deletions

diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index 0f947bcbad46..bbfe7d92d41c 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -573,6 +573,52 @@ error:
 }
 
 /*
+ * Move a link to a key from one keyring to another, displacing any matching
+ * key from the destination keyring.
+ *
+ * The key must grant the caller Link permission and both keyrings must grant
+ * the caller Write permission.  There must also be a link in the from keyring
+ * to the key.  If both keyrings are the same, nothing is done.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_keyring_move(key_serial_t id, key_serial_t from_ringid,
+			 key_serial_t to_ringid, unsigned int flags)
+{
+	key_ref_t key_ref, from_ref, to_ref;
+	long ret;
+
+	if (flags & ~KEYCTL_MOVE_EXCL)
+		return -EINVAL;
+
+	key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE, KEY_NEED_LINK);
+	if (IS_ERR(key_ref))
+		return PTR_ERR(key_ref);
+
+	from_ref = lookup_user_key(from_ringid, 0, KEY_NEED_WRITE);
+	if (IS_ERR(from_ref)) {
+		ret = PTR_ERR(from_ref);
+		goto error2;
+	}
+
+	to_ref = lookup_user_key(to_ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE);
+	if (IS_ERR(to_ref)) {
+		ret = PTR_ERR(to_ref);
+		goto error3;
+	}
+
+	ret = key_move(key_ref_to_ptr(key_ref), key_ref_to_ptr(from_ref),
+		       key_ref_to_ptr(to_ref), flags);
+
+	key_ref_put(to_ref);
+error3:
+	key_ref_put(from_ref);
+error2:
+	key_ref_put(key_ref);
+	return ret;
+}
+
+/*
  * Return a description of a key to userspace.
  *
  * The key must grant the caller View permission for this to work.
@@ -1772,6 +1818,12 @@ SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3,
 			(const void __user *)arg4,
 			(const void __user *)arg5);
 
+	case KEYCTL_MOVE:
+		return keyctl_keyring_move((key_serial_t)arg2,
+					   (key_serial_t)arg3,
+					   (key_serial_t)arg4,
+					   (unsigned int)arg5);
+
 	default:
 		return -EOPNOTSUPP;
 	}