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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 DA241C433E0 for ; Thu, 18 Jun 2020 02:03:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ACECE221F8 for ; Thu, 18 Jun 2020 02:03:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592445781; bh=kZs7yTu0LGA3GelZtkTTklM55dg2istBIFGH5972M80=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=o9bHitrztmhs3UbJ4E2FXkkJJl3qaKGF8g+9aRN2EII+KUxlNP8vH+TV/BuuJAW3A gYjo7fC+J5UQXYJf1ccZ7eWYQR2HdSwanhwEqmPgrrtXmNRjlu99TI2IsLsBqcpC5T ygxyZu8QTNI1dif4XhIhXKTeo7+eWccAKl6RSk3Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732847AbgFRCDA (ORCPT ); Wed, 17 Jun 2020 22:03:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:57584 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727092AbgFRBXn (ORCPT ); Wed, 17 Jun 2020 21:23:43 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C5B3D20B1F; Thu, 18 Jun 2020 01:23:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592443422; bh=kZs7yTu0LGA3GelZtkTTklM55dg2istBIFGH5972M80=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tZNU7Ihi7XOrBEmQ64vVmm363PYdHKPiGFbEo1z5pfXlgPlvXIbukmlPhdbpa766X /L7zwMd4kqpgmOA8HLCzGusmN7oqrRun4MZyFkrb8SivsODxh4FVjc+o7RhmCHhADJ 0GNMaEB3WZ85wPxZPWMG04xCPOAmFUCG7dR5yFhQ= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Xiyu Yang , Xin Tan , Greg Kroah-Hartman , Sasha Levin , devel@driverdev.osuosl.org Subject: [PATCH AUTOSEL 4.19 063/172] staging: gasket: Fix mapping refcnt leak when register/store fails Date: Wed, 17 Jun 2020 21:20:29 -0400 Message-Id: <20200618012218.607130-63-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200618012218.607130-1-sashal@kernel.org> References: <20200618012218.607130-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xiyu Yang [ Upstream commit e3436ce60cf5f5eaedda2b8c622f69feb97595e2 ] gasket_sysfs_register_store() invokes get_mapping(), which returns a reference of the specified gasket_sysfs_mapping object to "mapping" with increased refcnt. When gasket_sysfs_register_store() returns, local variable "mapping" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in one exception handling path of gasket_sysfs_register_store(). When gasket_dev is NULL, the function forgets to decrease the refcnt increased by get_mapping(), causing a refcnt leak. Fix this issue by calling put_mapping() when gasket_dev is NULL. Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Link: https://lore.kernel.org/r/1587618941-13718-1-git-send-email-xiyuyang19@fudan.edu.cn Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/staging/gasket/gasket_sysfs.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/staging/gasket/gasket_sysfs.c b/drivers/staging/gasket/gasket_sysfs.c index 9c982f1c0881..5986c67bc7ec 100644 --- a/drivers/staging/gasket/gasket_sysfs.c +++ b/drivers/staging/gasket/gasket_sysfs.c @@ -377,6 +377,7 @@ ssize_t gasket_sysfs_register_store(struct device *device, gasket_dev = mapping->gasket_dev; if (!gasket_dev) { dev_err(device, "Device driver may have been removed\n"); + put_mapping(mapping); return 0; } -- 2.25.1