Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756533AbZKDO0W (ORCPT ); Wed, 4 Nov 2009 09:26:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756492AbZKDO0W (ORCPT ); Wed, 4 Nov 2009 09:26:22 -0500 Received: from out01.mta.xmission.com ([166.70.13.231]:47982 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756478AbZKDO0U (ORCPT ); Wed, 4 Nov 2009 09:26:20 -0500 To: "Serge E. Hallyn" Cc: Greg Kroah-Hartman , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, sds@tycho.nsa.gov, jmorris@namei.org, casey@schaufler-ca.com, linux-security-module@vger.kernel.org Subject: Re: [PATCH] sysfs: Don't leak secdata when a sysfs_dirent is freed. References: <20091104140913.GA4355@us.ibm.com> From: ebiederm@xmission.com (Eric W. Biederman) Date: Wed, 04 Nov 2009 06:26:19 -0800 In-Reply-To: <20091104140913.GA4355@us.ibm.com> (Serge E. Hallyn's message of "Wed\, 4 Nov 2009 08\:09\:13 -0600") Message-ID: User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-XM-SPF: eid=;;;mid=;;;hst=in01.mta.xmission.com;;;ip=76.21.114.89;;;frm=ebiederm@xmission.com;;;spf=neutral X-SA-Exim-Connect-IP: 76.21.114.89 X-SA-Exim-Mail-From: ebiederm@xmission.com X-SA-Exim-Version: 4.2.1 (built Thu, 25 Oct 2007 00:26:12 +0000) X-SA-Exim-Scanned: No (on in01.mta.xmission.com); Unknown failure Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2068 Lines: 63 "Serge E. Hallyn" writes: > Quoting Eric W. Biederman (ebiederm@xmission.com): >> >> While refreshing my sysfs patches I noticed a leak in the secdata >> implementation. We don't free the secdata when we free the >> sysfs dirent. >> >> This is a bug in 2.6.32-rc5 that we really should close. >> >> Signed-off-by: Eric W. Biederman > > I'm surprised no kmemleak or anything has found this - but I guess > not many sites hand-set custom selinux contexts on sysfs? I don't expect so since you couldn't customize it in 2.6.31. This is brand new code, and this corner case was just overlooked in the review. Eric > Acked-by: Serge Hallyn > >> --- >> >> fs/sysfs/dir.c | 4 ++++ >> 1 files changed, 4 insertions(+), 0 deletions(-) >> >> diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c >> index 5fad489..e020183 100644 >> --- a/fs/sysfs/dir.c >> +++ b/fs/sysfs/dir.c >> @@ -21,6 +21,7 @@ >> #include >> #include >> #include >> +#include >> #include "sysfs.h" >> >> DEFINE_MUTEX(sysfs_mutex); >> @@ -285,6 +286,9 @@ void release_sysfs_dirent(struct sysfs_dirent * sd) >> sysfs_put(sd->s_symlink.target_sd); >> if (sysfs_type(sd) & SYSFS_COPY_NAME) >> kfree(sd->s_name); >> + if (sd->s_iattr && sd->s_iattr->ia_secdata) >> + security_release_secctx(sd->s_iattr->ia_secdata, >> + sd->s_iattr->ia_secdata_len); >> kfree(sd->s_iattr); >> sysfs_free_ino(sd->s_ino); >> kmem_cache_free(sysfs_dir_cachep, sd); >> -- >> 1.6.5.2.143.g8cc62 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-security-module" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html -- 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/