diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index d14ace88e529..5a5efa26ed0e 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -677,12 +677,14 @@ long keyctl_describe_key(key_serial_t keyid,
 
 	/* calculate how much information we're going to return */
 	ret = -ENOMEM;
+	down_read(&key->sem);
 	infobuf = kasprintf(GFP_KERNEL,
 			    "%s;%d;%d;%08x;",
 			    key->type->name,
 			    from_kuid_munged(current_user_ns(), key->uid),
 			    from_kgid_munged(current_user_ns(), key->gid),
 			    key->perm);
+	up_read(&key->sem);
 	if (!infobuf)
 		goto error2;
 	infolen = strlen(infobuf);