From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754708AbbHEWN3 (ORCPT ); Wed, 5 Aug 2015 18:13:29 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:38469 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754398AbbHEVuK (ORCPT ); Wed, 5 Aug 2015 17:50:10 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Paul Moore , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 037/107] selinux: don't waste ebitmap space when importing NetLabel categories Date: Wed, 5 Aug 2015 14:48:29 -0700 Message-Id: <1438811379-384-38-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1438811379-384-1-git-send-email-kamal@canonical.com> References: <1438811379-384-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19.8-ckt5 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Paul Moore commit 3324603524925c7727207027d1c15e597412d15e upstream. At present we don't create efficient ebitmaps when importing NetLabel category bitmaps. This can present a problem when comparing ebitmaps since ebitmap_cmp() is very strict about these things and considers these wasteful ebitmaps not equal when compared to their more efficient counterparts, even if their values are the same. This isn't likely to cause problems on 64-bit systems due to a bit of luck on how NetLabel/CIPSO works and the default ebitmap size, but it can be a problem on 32-bit systems. This patch fixes this problem by being a bit more intelligent when importing NetLabel category bitmaps by skipping over empty sections which should result in a nice, efficient ebitmap. Signed-off-by: Paul Moore Signed-off-by: Kamal Mostafa --- security/selinux/ss/ebitmap.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/security/selinux/ss/ebitmap.c b/security/selinux/ss/ebitmap.c index afe6a26..57644b1 100644 --- a/security/selinux/ss/ebitmap.c +++ b/security/selinux/ss/ebitmap.c @@ -153,6 +153,12 @@ int ebitmap_netlbl_import(struct ebitmap *ebmap, if (offset == (u32)-1) return 0; + /* don't waste ebitmap space if the netlabel bitmap is empty */ + if (bitmap == 0) { + offset += EBITMAP_UNIT_SIZE; + continue; + } + if (e_iter == NULL || offset >= e_iter->startbit + EBITMAP_SIZE) { e_prev = e_iter; -- 1.9.1