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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 58AA2C433F5 for ; Thu, 19 May 2022 08:58:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235698AbiESI6T (ORCPT ); Thu, 19 May 2022 04:58:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43202 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229450AbiESI6R (ORCPT ); Thu, 19 May 2022 04:58:17 -0400 Received: from smtp-relay-canonical-1.canonical.com (smtp-relay-canonical-1.canonical.com [185.125.188.121]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 79ED79D07B; Thu, 19 May 2022 01:58:16 -0700 (PDT) Received: from [192.168.192.153] (unknown [50.126.114.69]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-canonical-1.canonical.com (Postfix) with ESMTPSA id 133E03F772; Thu, 19 May 2022 08:58:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical.com; s=20210705; t=1652950695; bh=6Oiy096Izr3Tq4XztfXw7/ZW6D9X51nuLlYFuMD7TmQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=kV/CHRNZ8/8/6TaUJ7JvtwUlZA7u8gYrz5wx3lfB9IsTH7dtAXsVE570QpXwUiX02 +j+DQ/CIBUVxEa0lq8el+X/LEjVo9TW3AcU47SBVQihm8HQV9dnVSFyhHVp55mnFgk 8ZJtULDrNmGkg91iJret+rjPQZemhhiginYk7CeRCBbJT4Xfyg2sy2jL/g8xaRBjvA nmbJzoasZx8/ythRDbOlRBJSSi4DruV16tviuGClObbaSs2ADk7+c/hntzKr9gA1vn tZGUpk7SMJj48xm9gK/rh5tcw8IIRUx9W4iHiXtWRsNY5l1ItgmxNez69BQkA1t0go kGjY4VKSO5OAg== Message-ID: Date: Thu, 19 May 2022 01:58:11 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Subject: Re: [PATCH] apparmor: fix reference count leak in aa_pivotroot() Content-Language: en-US To: Xin Xiong , James Morris , "Serge E. Hallyn" , Seth Arnold , linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org Cc: yuanxzhang@fudan.edu.cn, Xiyu Yang , Xin Tan References: <20220428033907.1658-1-xiongx18@fudan.edu.cn> From: John Johansen Organization: Canonical In-Reply-To: <20220428033907.1658-1-xiongx18@fudan.edu.cn> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/27/22 20:39, Xin Xiong wrote: > The aa_pivotroot() function has a reference counting bug in a specific > path. When aa_replace_current_label() returns on success, the function > forgets to decrement the reference count of “target”, which is > increased earlier by build_pivotroot(), causing a reference leak. > > Fix it by decreasing the refcount of “target” in that path. > > Fixes: 2ea3ffb7782a ("apparmor: add mount mediation") > Co-developed-by: Xiyu Yang > Signed-off-by: Xiyu Yang > Co-developed-by: Xin Tan > Signed-off-by: Xin Tan > Signed-off-by: Xin Xiong thanks I have pulled it into my tree Acked-by: John Johansen > --- > security/apparmor/mount.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/security/apparmor/mount.c b/security/apparmor/mount.c > index aa6fcfde3051..d0b19ab9137d 100644 > --- a/security/apparmor/mount.c > +++ b/security/apparmor/mount.c > @@ -718,6 +718,7 @@ int aa_pivotroot(struct aa_label *label, const struct path *old_path, > aa_put_label(target); > goto out; > } > + aa_put_label(target); > } else > /* already audited error */ > error = PTR_ERR(target);