From patchwork Thu Aug 20 09:20:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 265744 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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 10BAAC433DF for ; Thu, 20 Aug 2020 10:08:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DBA2D206DA for ; Thu, 20 Aug 2020 10:08:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597918114; bh=vXeEIzsqQBvfgLUHF5Suok51uUamakv2YzQy1CuxnzQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=F/5ik/wFMtWbigprNqKg6LZwvU3reOjfo6hCJHbEFZPIORrhZc9WJGAAFKj6ypMpc EFCdqwDCuMwlp2rOMfijE/GtGZQbBg9Nz/K4XUm5WwQjU0yfELB2D78Aqt841Lk8qp oSvQ6khk6Y4BxWGjpFFumK/w11eg6YRlrgKlNq/A= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730631AbgHTKId (ORCPT ); Thu, 20 Aug 2020 06:08:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:40808 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729792AbgHTKIc (ORCPT ); Thu, 20 Aug 2020 06:08:32 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 58D6C20738; Thu, 20 Aug 2020 10:08:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597918112; bh=vXeEIzsqQBvfgLUHF5Suok51uUamakv2YzQy1CuxnzQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hbHbUV1pokTtr/xltsFitJzxmWrEIKayMP8293VtYKuU05ZsnUDKK7DjaCrXJa6hL WM3oB4uB9vMQ7ar7Jm/6LS/KmMUdLmX4bRHiJKULwiaAdRAkhhENT1GrkOBsOTB72g +undpL3ajXfqFJ1RwsLp6o4itZPxKjojSn+yrEFU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xin Xiong , Xiyu Yang , Xin Tan , "David S. Miller" , Sasha Levin Subject: [PATCH 4.14 026/228] atm: fix atm_dev refcnt leaks in atmtcp_remove_persistent Date: Thu, 20 Aug 2020 11:20:01 +0200 Message-Id: <20200820091608.842161518@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200820091607.532711107@linuxfoundation.org> References: <20200820091607.532711107@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Xin Xiong [ Upstream commit 51875dad43b44241b46a569493f1e4bfa0386d86 ] atmtcp_remove_persistent() invokes atm_dev_lookup(), which returns a reference of atm_dev with increased refcount or NULL if fails. The refcount leaks issues occur in two error handling paths. If dev_data->persist is zero or PRIV(dev)->vcc isn't NULL, the function returns 0 without decreasing the refcount kept by a local variable, resulting in refcount leaks. Fix the issue by adding atm_dev_put() before returning 0 both when dev_data->persist is zero or PRIV(dev)->vcc isn't NULL. Signed-off-by: Xin Xiong Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/atm/atmtcp.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/atm/atmtcp.c b/drivers/atm/atmtcp.c index afebeb1c3e1e9..723bad1201cc5 100644 --- a/drivers/atm/atmtcp.c +++ b/drivers/atm/atmtcp.c @@ -432,9 +432,15 @@ static int atmtcp_remove_persistent(int itf) return -EMEDIUMTYPE; } dev_data = PRIV(dev); - if (!dev_data->persist) return 0; + if (!dev_data->persist) { + atm_dev_put(dev); + return 0; + } dev_data->persist = 0; - if (PRIV(dev)->vcc) return 0; + if (PRIV(dev)->vcc) { + atm_dev_put(dev); + return 0; + } kfree(dev_data); atm_dev_put(dev); atm_dev_deregister(dev);