Label some shell scripts from bridge-utils correctly. Maybe have ifdef
distro_debian around this, not sure what upstream is doing.
systemd_nspawn_t needs to manage the /etc/localtime symlink if you have a
labeled chroot.
Another dontaudit for mon_local_test_t to stop it spamming the logs.
Support a .d directory for dnsmasq config files.
systemd relabels everything in /dev and /run after loading the policy.
In these directories there is a socket file for udev, /run/udev/control,
which is not allowed to be relabelled from tmpfs_t:
avc: denied { relabelfrom } for pid=1 comm="systemd"
name="control" dev="tmpfs" ino=7027
scontext=system_u:system_r:init_t tcontext=system_u:object_r:tmpfs_t
tclass=sock_file permissive=1
avc: denied { relabelto } for pid=1 comm="systemd" name="control"
dev="tmpfs" ino=7027 scontext=system_u:system_r:init_t
tcontext=system_u:object_r:udev_var_run_t tclass=sock_file
permissive=1
/run/tmpfiles.d directory (used by systemd-tmpfiles service) is also
relabelled.
This is currently denied:
avc: denied { create } for pid=1 comm="systemd" name="pts"
scontext=system_u:system_r:init_t
tcontext=system_u:object_r:devpts_t tclass=dir permissive=1
systemd tries to create /dev/pts directly with its context type
"devpts_t", but this is not allowed:
avc: denied { associate } for pid=1 comm="systemd" name="pts"
scontext=system_u:object_r:devpts_t
tcontext=system_u:object_r:device_t
tclass=filesystem permissive=1
The following patch creates two additional interfaces for tun_tap_device_t to grant only read or only write access (rather than both read and write access). It is possible to open a tap device for only reading or only writing and this allows policy to match that use.
Signed-off-by: Dave Sugar <dsugar@tresys.com>
Commit 2e7553db63 ("Create / to /usr equivalence for bin, sbin, and
lib, from Russell Coker.") removed from corecommands.fc:
/usr/(.*/)?bin(/.*)? gen_context(system_u:object_r:bin_t,s0)
Consequently files like /usr/x86_64-w64-mingw32/bin/objdump get labeled
as usr_t:
$ matchpathcon /usr/x86_64-w64-mingw32/bin/objdump
/usr/x86_64-w64-mingw32/bin/objdump system_u:object_r:usr_t
Make such files labeled as bin_t again.
Remove complement (~) and wildcard (*) in allow rules so that there are no
unintentional additions when new permissions are declared.
This patch does not add or remove permissions from any rules.
When a program uses init_module() to load a module, the kernel checks
for system:load_module permission in the process type [1].
For example when systemd loads ip_tables modules (since
1d3087978a),
the following AVC denial gets reported:
avc: denied { module_load } for pid=1 comm="systemd"
scontext=system_u:system_r:init_t tcontext=system_u:system_r:init_t
tclass=system permissive=1
[1] The relevant kernel code is selinux_kernel_module_from_file() in
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/security/selinux/hooks.c?h=v4.11#n3836
/* init_module */
if (file == NULL)
return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
SYSTEM__MODULE_LOAD, NULL);
In this code, both source and target SIDs are current_sid().
Since Xen 4.7, /dev/xen/privcmd is used instead of /proc/xen/privcmd.
Add the device into the policy so `xenstored` can work.
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Kernel commit 6941857e82ae ("selinux: add a map permission check
for mmap") added a map permission check on mmap so that we can
distinguish memory mapped access (since it has different implications
for revocation). The purpose of a separate map permission check on
mmap(2) is to permit policy to prohibit memory mapping of specific files
for which we need to ensure that every access is revalidated, particularly
useful for scenarios where we expect the file to be relabeled at runtime
in order to reflect state changes (e.g. cross-domain solution, assured
pipeline without data copying). The kernel commit is anticipated to
be included in Linux 4.13.
This refpolicy change defines map permission for refpolicy. It mirrors
the definition in the kernel classmap by adding it to the common
definitions for files and sockets. This will break compatibility for
kernels that predate the dynamic class/perm mapping support (< 2.6.33,
< RHEL 6); on such kernels, one would instead need to add map permission
to the end of each file and socket access vector.
This change only allows map permission as needed, e.g. only in the
mmap_file_perms and exec_file_perms object permission sets
(since map is always required there) and only in specific interfaces
or modules where denials were observed in limited testing.
It is important to note that effective use of this permission requires
complete removal of unconfined, as otherwise unconfined domains will be
able to map all file types and therefore bypass the intended protection.
If we wanted to exclude map permission to all file types by default from
unconfined, we would need to add it to the list of permissions excluded from
files_unconfined_type in kernel/files.te.
Policies that depend on this permission not being allowed to specific file
types should also make use of neverallow rules to ensure that this is not
undermined by any allow rule, and ensure that they are performing neverallow
checking at policy build time (e.g. make validate) or runtime (e.g.
semanage.conf expand-check=1).
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Every Infiniband network will have a default pkey, so that is labeled.
The rest of the pkey configuration is network specific. The policy allows
access to the default and unlabeled pkeys for sysadm and staff users.
kernel_t is allowed access to all pkeys, which it needs to process and
route management datagrams.
Endports are all unlabeled by default, sysadm users are allowed to
manage the subnet on unlabeled endports. kernel_t is allowed to manage
the subnet on all ibendports, which is required for configuring the HCA.
This patch requires selinux series: "SELinux user space support for
Infiniband RDMA", due to the new ipkeycon labeling mechanism.
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Setting this service option to 'full' or 'strict' will also remount the
/etc directory. Allow this in the policy.
This fixes the systemd-networkd service, but will also positively affect
any other service using the above hardening option.
This patch is slightly more involved than just running sed. It also adds
typealias rules and doesn't change the FC entries.
The /dev/apm_bios device doesn't exist on modern systems. I have left that
policy in for the moment on the principle of making one change per patch. But
I might send another patch to remove that as it won't exist with modern
kernels.
This patch adds three new file contexts for script executables
belonging to new Gnome applications (weather application and
sound recorder).
Signed-off-by: Guido Trentalancia <guido@trentalancia.net>
Patches for modutils, at least one of which is needed to generate an initramfs
on Debian.
Patch to allow lvm to talk to fifos from dpkg_script_t for postinst scripts
etc.
Patch for brctl to allow it to create sysfs files.
This patch adds a lot of policy that is needed to setup an initramfs and grub
on Debian nowadays.
Also changed a comment about ia64 to correctly mention EFI.
This patch adds an interface to manage systemd_passwd_var_run_t symlinks that
I'll add another patch to use shortly.
It has a number of changes needed by systemd_logind_t to set permissions for
local logins.
It has some more permissions that systemd_machined_t needs, I don't think it's
everything that systemd_machined_t needs but it's a start.
It has some changes for udev_t for systemd-udevd.
On systems such as Arch Linux, all programs which are usually located in
/bin, /sbin, /usr/bin and /usr/sbin are present in /usr/bin and the
other locations are symbolic links to this directory. With such a
configuration, the file contexts which define types for files in
/bin, /sbin and /usr/sbin need to be duplicated to provide definitions
for /usr/bin/...
As the "/bin vs. /usr/bin" part of the needed definitions has already
been done with the "usr merge" patches, the next step consists in
duplicating file contexts for /usr/sbin. This is what this patch does
for all modules which are not in contrib.
This is the second iteration of an idea I have previously posted on
http://oss.tresys.com/pipermail/refpolicy/2017-March/009176.html
This patch doesn't do everything that is needed to have systemd-nspawn work.
But it does everything that is needed and which I have written in a clear and
uncontroversial way. I think it's best to get this upstream now and then
either have a separate discussion about the more difficult issues, or wait
until I devise a way of solving those problems that's not too hacky.
Who knows, maybe someone else will devise a brilliant solution to the remaining
issues after this is accepted upstream.
Also there's a tiny patch for systemd_machined_t that is required by
systemd_nspawn_t.
Description: systemd-nspawn
Author: Russell Coker <russell@coker.com.au>
Last-Update: 2017-03-29
I believe that I have addressed all the issues Chris raised, so here's a newer
version of the patch which applies to today's git version.
Description: systemd-resolved, sessions, and tmpfiles patches
Author: Russell Coker <russell@coker.com.au>
Last-Update: 2017-03-26
Here's the latest version of my patch to remove all /var/run when it's not
needed. I have removed the subst thing from the patch, but kept a
distro_debian bit that relies on it. So with this patch the policy won't
install if you build it with distro_debian unless you have my subst patch.
Chris, if your automated tests require that it build and install with
distro_debian then skip the patch for sysnetwork.fc.
From Russell Coker
When using setfiles to validate file contexts of Debian modular policy
(with DISTRO=debian and MONOLITHIC=n), it fails with:
tmp/all_mods.fc: line 527 is missing fields
tmp/all_mods.fc: line 527 is missing fields
tmp/all_mods.fc: Invalid argument
Here is the content of tmp/all_mods.fc around line 527:
# this is a static /dev dir "backup mount"
# if you want to disable udev, youll have to boot permissive and relabel!
/dev/\.static -d system_u:object_r:device_t
/dev/\.static/dev -d system_u:object_r:device_t
/dev/\.static/dev/(.*)? <<none>>
'
The quote of "you'll" has been eaten by m4 and there is a spurious quote
on the last line, which is reported by setfiles. Fix this by removing
the quote in the comment.
Here is an example of a failed build on Travis-CI:
https://travis-ci.org/fishilico/selinux-refpolicy-patched/jobs/205951446
userdomains should not alter labels of kernel pseudo filesystems, but allowing setfiles/restorecon(d) to check the contexts helps spotting incorrect labels
When you merged the mon patch you removed the ability for mon_t to execute
lib_t files.
The following patch re-enables the ability to execute alert scripts.
Since 8e01472078763ebc1eaea089a1adab75dd982ccd, it's possible to use
genfscon for sysfs.
This patch should help to deprecate distribution specific call to
restorecon or tmpfiles to restore /sys/devices/system/cpu/online during
boot.
Thanks to Dominick for the tip.
Some policy modules define file contexts in /bin, /sbin and /lib without
defining similar file contexts in the same directory under /usr.
Add these missing file contexts when there are outside ifdef blocks.
This patch adds missing permissions in the kernel module that prevent
to run it without the unconfined module.
This second version improves the comment section of new interfaces:
"Domain" is replaced by "Domain allowed access".
Signed-off-by: Guido Trentalancia <guido@trentalancia.net>
Interface fs_register_binary_executable_type allow registering
interpreters using a filesystem monted on /proc/sys/fs/binfmt_misc. In
order to access this filesystem, the process needs to search every
parent directory of the mountpoint.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
Remove file context aliases and update file context paths to use the /run filesystem path.
Add backward compatibility file context alias for /var/run using applications like https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=783321
Lock files are still seated at /var/lock
The kernel_read_unix_sysctls() and kernel_rw_unix_sysctls() currenly
don't allow listing the /proc/sys/net/unix directory, contrary to the
other sysctl interfaces.
When reading or managing noxattr fs files or symbolic links, also
let the user list noxattr fs directories.
This patch should be applied after the following one:
http://oss.tresys.com/pipermail/refpolicy/2016-October/008539.html
"Let users read/manage symlinks on fs that do not support xattr"
posted on Sat, 29 Oct 2016 15:39:46 UTC.
Signed-off-by: Guido Trentalancia <guido@trentalancia.net>
Let unprivileged and administrative users read symbolic links on
filesystems that do not support extended attributes (xattr) such
as cdroms, FAT, NTFS and so on.
Signed-off-by: Guido Trentalancia <guido@trentalancia.net>
On Tuesday, 2 August 2016 7:59:28 PM AEDT Chris PeBenito wrote:
> On 07/31/16 08:34, Russell Coker wrote:
> > The following patch deals with a single binary for modutils, so depmod_t,
> > and insmod_t are merged.
>
> Since the main SELinux distros (including RHEL/CentOS 7) all have merged
> modutils these days, I'm open to taking a patch that fully merges these
> domains (in which case renaming to kmod_t, with proper aliasing seems
> the best idea).
>
> However, it's been some time since I used a busybox-based system; does
> busybox still have separated tools? Yes, this is a bit of an obvious
> question since busybox is also single-binary, but IIRC, the embedded
> guys made some tiny helper scripts or executables so proper
> transitioning could occur. Separate domains may still make sense.
As we have had no response from Busybox users in the last 3 months and also no
response to the thread Luis started in 2013 I think it's safe to assume that
they don't need this.
I've attached a new patch which renames to kmod_t as you suggested. Please
consider it for inclusion.
--
My Main Blog http://etbe.coker.com.au/
My Documents Blog http://doc.coker.com.au/
Description: Change modutils policy to match the use of a single binary
Author: Russell Coker <russell@coker.com.au>
Last-Update: 2014-06-25
The "module_load" permission has been recently added to the "system"
class (kernel 4.7).
The following patch updates the Reference Policy so that the new
permission is allowed when a kernel module should be loaded.
To preserve the module encapsulation, a new interface is defined
in the kernel files module and that interface is then used in the
kernel module.
A short note is added about unneeded permissions that set the
kernel scheduling parameters (might lead to service disruption).
Signed-off-by: Guido Trentalancia <guido@trentalancia.net>
/etc/sysconfig/libvirtd does not have the executable bit set, so it does
not make sense for it to be labelled bin_t. I can't seem to find the
reason it was set that way originally.
Signed-off-by: Garrett Holmstrom <gholms@devzero.com>
With the new "cgroup2" system added in kernel 4.5, systemd is getting
selinux denials when manipulating the cgroup hierarchy.
Pull request in systemd with cgroup2 support:
https://github.com/systemd/systemd/pull/2903
AVC when writing process numbers to move them to the right cgroup:
Mar 29 19:58:30 rawhide kernel: audit: type=1400
audit(1459295910.257:68): avc: denied { write } for pid=1
comm="systemd" name="cgroup.procs" dev="cgroup2" ino=6
scontext=system_u:system_r:init_t:s0
tcontext=system_u:object_r:unlabeled_t:s0 tclass=file permissive=1
In this case new filesystem "cgroup2" need to be labeled as cgroup_t.
Signed-off-by: Lukas Vrabec <lvrabec@redhat.com>
When a device gets removed, for example with "cryptsetup close",
kdevtmpfs (a kernel thread) removes its entry from devtmpfs filesystem:
avc: denied { unlink } for pid=48 comm="kdevtmpfs"
name="dm-4" dev="devtmpfs" ino=144111
scontext=system_u:system_r:kernel_t
tcontext=system_u:object_r:fixed_disk_device_t tclass=blk_file
Allow this access on systems using systemd.
On Arch Linux, /usr/lib/gvfs directory contains both executable files
(gvfsd, gvfs-udisks2-volume-monitor...) and libraries (libgvfscommon.so
and libgvfsdaemon.so). As all executable files are prefixed with
"gfvs", so use this to distinguish them with the libraries.
This fixes the following AVC denials, reported from geoclue service
using a library wrongly labelled bin_t:
avc: denied { read } for pid=14872 comm="geoclue"
name="libgvfscommon.so" dev="dm-0" ino=3152594
scontext=system_u:system_r:geoclue_t
tcontext=system_u:object_r:bin_t tclass=file permissive=1
avc: denied { open } for pid=14872 comm="geoclue"
path="/usr/lib/gvfs/libgvfscommon.so" dev="dm-0" ino=3152594
scontext=system_u:system_r:geoclue_t
tcontext=system_u:object_r:bin_t tclass=file permissive=1
avc: denied { execute } for pid=14872 comm="geoclue"
path="/usr/lib/gvfs/libgvfscommon.so" dev="dm-0" ino=3152594
scontext=system_u:system_r:geoclue_t
tcontext=system_u:object_r:bin_t tclass=file permissive=1
