Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932905Ab1FWRfn (ORCPT ); Thu, 23 Jun 2011 13:35:43 -0400 Received: from mail.windriver.com ([147.11.1.11]:34109 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932686Ab1FWRfi (ORCPT ); Thu, 23 Jun 2011 13:35:38 -0400 From: Paul Gortmaker To: stable@kernel.org, linux-kernel@vger.kernel.org Cc: stable-review@kernel.org, Eric Paris , Paul Gortmaker Subject: [34-longterm 069/247] SELinux: do not compute transition labels on mountpoint labeled filesystems Date: Thu, 23 Jun 2011 13:32:17 -0400 Message-Id: <1308850515-15242-10-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.7.4.4 In-Reply-To: <1308850515-15242-1-git-send-email-paul.gortmaker@windriver.com> References: <1308849690-14530-1-git-send-email-paul.gortmaker@windriver.com> <1308850515-15242-1-git-send-email-paul.gortmaker@windriver.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2514 Lines: 66 From: Eric Paris ------------------- This is a commit scheduled for the next v2.6.34 longterm release. If you see a problem with using this for longterm, please comment. ------------------- commit 415103f9932d45f7927f4b17e3a9a13834cdb9a1 upstream. selinux_inode_init_security computes transitions sids even for filesystems that use mount point labeling. It shouldn't do that. It should just use the mount point label always and no matter what. This causes 2 problems. 1) it makes file creation slower than it needs to be since we calculate the transition sid and 2) it allows files to be created with a different label than the mount point! # id -Z staff_u:sysadm_r:sysadm_t:s0-s0:c0.c1023 # sesearch --type --class file --source sysadm_t --target tmp_t Found 1 semantic te rules: type_transition sysadm_t tmp_t : file user_tmp_t; # mount -o loop,context="system_u:object_r:tmp_t:s0" /tmp/fs /mnt/tmp # ls -lZ /mnt/tmp drwx------. root root system_u:object_r:tmp_t:s0 lost+found # touch /mnt/tmp/file1 # ls -lZ /mnt/tmp -rw-r--r--. root root staff_u:object_r:user_tmp_t:s0 file1 drwx------. root root system_u:object_r:tmp_t:s0 lost+found Whoops, we have a mount point labeled filesystem tmp_t with a user_tmp_t labeled file! Signed-off-by: Eric Paris Reviewed-by: Reviewed-by: James Morris Signed-off-by: Paul Gortmaker --- security/selinux/hooks.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 5feecb4..0b459c8 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2595,7 +2595,10 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir, sid = tsec->sid; newsid = tsec->create_sid; - if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { + if ((sbsec->flags & SE_SBINITIALIZED) && + (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) + newsid = sbsec->mntpoint_sid; + else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { rc = security_transition_sid(sid, dsec->sid, inode_mode_to_security_class(inode->i_mode), &newsid); -- 1.7.4.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/