linux-kernel - Re: [PATCH 2/2] file capabilities: remove CONFIG_SECURITY_FILE

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20080924234857.GA22375@sequoia.sous-sol.org>
Date:	Wed, 24 Sep 2008 16:49:03 -0700
From:	Chris Wright <chrisw@...s-sol.org>
To:	"Serge E. Hallyn" <serue@...ibm.com>
Cc:	lkml <linux-kernel@...r.kernel.org>,
	linux-security-module@...r.kernel.org,
	James Morris <jmorris@...hat.com>,
	Andrew Morgan <morgan@...nel.org>,
	Andreas Gruenbacher <agruen@...e.de>,
	Andrew Morton <akpm@...l.org>,
	Chris Wright <chrisw@...s-sol.org>,
	Randy Dunlap <randy.dunlap@...cle.com>
Subject: Re: [PATCH 2/2] file capabilities: remove
	CONFIG_SECURITY_FILE_CAPABILITIES

* Serge E. Hallyn (serue@...ibm.com) wrote:
> Remove the option to compile the kernel without file capabilities.  Not
> compiling file capabilities actually makes the kernel less safe, as it
> includes the possibility for a task changing another task's capabilities.
> 
> Some are concerned that userspace tools (and user education) are not
> up to the task of properly configuring file capabilities on a system.
> For those cases, there is now the ability to boot with the no_file_caps
> boot option.  This will prevent file capabilities from being used in
> the capabilities recalculation at exec, but will not change the rest
> of the kernel behavior which used to be switchable using the
> CONFIG_SECURITY_FILE_CAPABILITIES option.

(note: defconfig has CONFIG_SECURITY_FILE_CAPABILITIES=y)
   text    data     bss     dec     hex filename
6805157 1018344  671900 8495401  81a129 obj64-defconfig/vmlinux
6805151 1018368  671900 8495419  81a13b obj64-defconfig-patch1/vmlinux
6805151 1018368  671900 8495419  81a13b obj64-defconfig-patch2/vmlinux
6804605 1018344  671900 8494849  819f01 obj64-nofcap/vmlinux
6804604 1018344  671900 8494848  819f00 obj64-nofcap-patch1/vmlinux
6805150 1018368  671900 8495418  81a13a obj64-nofcap-patch2/vmlinux

The last 2 show the real diff now, add 570 bytes by effectively forcing
CONFIG_SECURITY_FILE_CAPABILITIES on.

What is being done to enable userspace in distros to make those 570
bytes generally useful?

thanks,
-chris
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/