From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5E970C43381 for ; Mon, 18 Mar 2019 16:57:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3758F20863 for ; Mon, 18 Mar 2019 16:57:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727142AbfCRQ5M (ORCPT ); Mon, 18 Mar 2019 12:57:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50512 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726837AbfCRQ5L (ORCPT ); Mon, 18 Mar 2019 12:57:11 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B6B9EF74D0; Mon, 18 Mar 2019 16:57:11 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-120-17.rdu2.redhat.com [10.10.120.17]) by smtp.corp.redhat.com (Postfix) with ESMTP id BF0A660FAB; Mon, 18 Mar 2019 16:57:10 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH] vfs: Fix refcounting of filenames in fs_parser From: David Howells To: viro@zeniv.linux.org.uk Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, dhowells@redhat.com Date: Mon, 18 Mar 2019 16:57:09 +0000 Message-ID: <155292822993.1511.7755301484525814050.stgit@warthog.procyon.org.uk> User-Agent: StGit/unknown-version MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Mon, 18 Mar 2019 16:57:11 +0000 (UTC) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Fix an overput in which filename_lookup() unconditionally drops a ref to the filename it was given, but this isn't taken account of in the caller, fs_lookup_param(). Addresses-Coverity-ID: 1443811 ("Use after free") Signed-off-by: David Howells --- fs/fs_parser.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/fs_parser.c b/fs/fs_parser.c index 842e8f749db6..be86703ec371 100644 --- a/fs/fs_parser.c +++ b/fs/fs_parser.c @@ -268,6 +268,7 @@ int fs_lookup_param(struct fs_context *fc, return invalf(fc, "%s: not usable as path", param->key); } + f->refcnt++; /* filename_lookup() drops our ref. */ ret = filename_lookup(param->dirfd, f, flags, _path, NULL); if (ret < 0) { errorf(fc, "%s: Lookup failure for '%s'", param->key, f->name);