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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 D9066C433DF for ; Tue, 26 May 2020 19:08:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9F51C20776 for ; Tue, 26 May 2020 19:08:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590520130; bh=Pb3w8EfsuE0U2OZBSl6Xdlzscep5epzAj1g46ZuRWZs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=OSSqxMlrWC6M63JP9u3V+KB7KKvLdFKSFxb359lr9tXqjzsKHmDjGl0FtTWYb/iSE C0uEGskD5fnpyt/jC61053CG6vM4AP7zND83O65DJq7usC+aBd65//wfYTA3bDN/16 SvotE9bvclhtPqyrorAp7o1PwYSxG5EVNT1RfGPw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391033AbgEZTIu (ORCPT ); Tue, 26 May 2020 15:08:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:37774 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391806AbgEZTIp (ORCPT ); Tue, 26 May 2020 15:08:45 -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 A4C8D20776; Tue, 26 May 2020 19:08:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590520125; bh=Pb3w8EfsuE0U2OZBSl6Xdlzscep5epzAj1g46ZuRWZs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IuFaiC7vmQj6z+mhYuzWds/vnuUO0dMKLXr0yIFzl6ZpbegtUGZRrXkX4mU6K63RQ jMKgEmpdyFfzOIzM4YPAoYJn078VgUHS0OfiLJFMNUbtyEf6QVkhP81up3zBltHe7N /rfRk5ZzHiXDONAyfg88dO8PkGtuoxEyJ9+W1a0o= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiyu Yang , Xin Tan , John Johansen Subject: [PATCH 5.4 067/111] apparmor: fix potential label refcnt leak in aa_change_profile Date: Tue, 26 May 2020 20:53:25 +0200 Message-Id: <20200526183939.201163831@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200526183932.245016380@linuxfoundation.org> References: <20200526183932.245016380@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 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 commit a0b845ffa0d91855532b50fc040aeb2d8338dca4 upstream. aa_change_profile() invokes aa_get_current_label(), which returns a reference of the current task's label. According to the comment of aa_get_current_label(), the returned reference must be put with aa_put_label(). However, when the original object pointed by "label" becomes unreachable because aa_change_profile() returns or a new object is assigned to "label", reference count increased by aa_get_current_label() is not decreased, causing a refcnt leak. Fix this by calling aa_put_label() before aa_change_profile() return and dropping unnecessary aa_get_current_label(). Fixes: 9fcf78cca198 ("apparmor: update domain transitions that are subsets of confinement at nnp") Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Signed-off-by: John Johansen Signed-off-by: Greg Kroah-Hartman --- security/apparmor/domain.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/security/apparmor/domain.c +++ b/security/apparmor/domain.c @@ -1334,6 +1334,7 @@ int aa_change_profile(const char *fqname ctx->nnp = aa_get_label(label); if (!fqname || !*fqname) { + aa_put_label(label); AA_DEBUG("no profile name"); return -EINVAL; } @@ -1352,8 +1353,6 @@ int aa_change_profile(const char *fqname op = OP_CHANGE_PROFILE; } - label = aa_get_current_label(); - if (*fqname == '&') { stack = true; /* don't have label_parse() do stacking */