Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760149AbdLRSd1 (ORCPT ); Mon, 18 Dec 2017 13:33:27 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:60916 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932963AbdLRPtv (ORCPT ); Mon, 18 Dec 2017 10:49:51 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Jeffery , David Howells , James Morris , Eric Biggers Subject: [PATCH 3.18 09/69] Dont leak a key reference if request_key() tries to use a revoked keyring Date: Mon, 18 Dec 2017 16:47:55 +0100 Message-Id: <20171218152737.047280267@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171218152735.055508271@linuxfoundation.org> References: <20171218152735.055508271@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1247 Lines: 37 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Jeffery commit d0709f1e66e8066c4ac6a54620ec116aa41937c0 upstream. If a request_key() call to allocate and fill out a key attempts to insert the key structure into a revoked keyring, the key will leak, using memory and part of the user's key quota until the system reboots. This is from a failure of construct_alloc_key() to decrement the key's reference count after the attempt to insert into the requested keyring is rejected. key_put() needs to be called in the link_prealloc_failed callpath to ensure the unused key is released. Signed-off-by: David Jeffery Signed-off-by: David Howells Signed-off-by: James Morris Signed-off-by: Eric Biggers Signed-off-by: Greg Kroah-Hartman --- security/keys/request_key.c | 1 + 1 file changed, 1 insertion(+) --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -437,6 +437,7 @@ link_check_failed: link_prealloc_failed: mutex_unlock(&user->cons_lock); + key_put(key); kleave(" = %d [prelink]", ret); return ret;