From patchwork Tue Jun 23 19:52:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 223561 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=-10.0 required=3.0 tests=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 5CE62C433DF for ; Tue, 23 Jun 2020 20:08:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 30CC7206C3 for ; Tue, 23 Jun 2020 20:08:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592942891; bh=xlGFGp69053SdoDQvg0jjtckRZObmKizq7MUoMM0yy8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=rQdeOsIESoM2ppYhRokB0TGDwJRujgLE57EdmXOLBXAvJAX/yX9DPKShHRD2tytCP GWAJIZYG36jTT2fvCWA+1FD4qe58AzgFlo+86eDRO+67HWSntCLY4eYRLHh6LqyZvz Nhtilkssujnb7exAuLjZ3ryMTTUw7/3kfHnY43ZU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387867AbgFWUIJ (ORCPT ); Tue, 23 Jun 2020 16:08:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:49054 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387833AbgFWUIH (ORCPT ); Tue, 23 Jun 2020 16:08:07 -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 6835D206C3; Tue, 23 Jun 2020 20:08:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592942887; bh=xlGFGp69053SdoDQvg0jjtckRZObmKizq7MUoMM0yy8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=swD1ZA4xlpXgANakQ8BALRgjTMx+jKGDEkdD8hRrJZxxGNpPDl5BvFv3GUmr/5jBm xw+LC0pik7d8jIBVriTrCS2vxg7SrIjhZjeYiLdTtKGnsN6lUrNYhse5Hwjp97C6PM f47XAJWJeE3lmm/DssR7lHwhMZpoEiUghJkAKY5E= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiyu Yang , Xin Tan , Sasha Levin Subject: [PATCH 5.7 133/477] staging: gasket: Fix mapping refcnt leak when put attribute fails Date: Tue, 23 Jun 2020 21:52:10 +0200 Message-Id: <20200623195413.892271810@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200623195407.572062007@linuxfoundation.org> References: <20200623195407.572062007@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: Xiyu Yang [ Upstream commit 57a66838e1494cd881b7f4e110ec685736e8e3ca ] gasket_sysfs_put_attr() invokes get_mapping(), which returns a reference of the specified gasket_sysfs_mapping object to "mapping" with increased refcnt. When gasket_sysfs_put_attr() returns, local variable "mapping" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in one path of gasket_sysfs_put_attr(). When mapping attribute is unknown, the function forgets to decrease the refcnt increased by get_mapping(), causing a refcnt leak. Fix this issue by calling put_mapping() when put attribute fails due to unknown attribute. Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Link: https://lore.kernel.org/r/1587618895-13660-1-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 5f0e089573a29..ad852ea1d4a92 100644 --- a/drivers/staging/gasket/gasket_sysfs.c +++ b/drivers/staging/gasket/gasket_sysfs.c @@ -339,6 +339,7 @@ void gasket_sysfs_put_attr(struct device *device, dev_err(device, "Unable to put unknown attribute: %s\n", attr->attr.attr.name); + put_mapping(mapping); } EXPORT_SYMBOL(gasket_sysfs_put_attr);