VBoxCreateUSBNode.sh creates character special files in /dev/vboxusb each time
a new USB device appears. This script is called by udev.
audit.log on a system in permissive mode before this patch contains:
type=AVC msg=audit(1396889711.890:175): avc: denied { execute } for pid=26284 comm="systemd-udevd" name="VBoxCreateUSBNode.sh" dev="sda5" ino=5899405 scontext=system_u:system_r:udev_t tcontext=unconfined_u:object_r:usr_t tclass=file
type=AVC msg=audit(1396889711.890:175): avc: denied { execute_no_trans } for pid=26284 comm="systemd-udevd" path="/usr/share/virtualbox/VBoxCreateUSBNode.sh" dev="sda5" ino=5899405 scontext=system_u:system_r:udev_t tcontext=unconfined_u:object_r:usr_t tclass=file
On ArchLinux, glibc package installs /usr/bin/getconf as a hard link to a file
in /usr/lib/getconf/. For example on a x86_64 machine:
$ ls -i -l /usr/bin/getconf /usr/lib/getconf/XBS5_LP64_OFF64
5900355 -rwxr-xr-x. 4 root root 22880 Feb 28 04:53 /usr/bin/getconf
5900355 -rwxr-xr-x. 4 root root 22880 Feb 28 04:53 /usr/lib/getconf/XBS5_LP64_OFF64
Such configuration produces an instability when labeling the files with
"restorecon -Rv /":
restorecon reset /usr/bin/getconf context unconfined_u:object_r:lib_t:s0->unconfined_u:object_r:bin_t:s0
restorecon reset /usr/lib/getconf/XBS5_LP64_OFF64 context unconfined_u:object_r:bin_t:s0->unconfined_u:object_r:lib_t:s0
As /usr/lib/getconf directory only contains executable programs, this issue is
fixed by labeling this directory and its content "bin_t".
/sys/fs/cgroup is a tmpfs which contains cgroup mounts and symlinks such as
cpu and cpuacct. Running restorecon makes this warning happen:
restorecon: Warning no default label for /sys/fs/cgroup/cpu
Declare a file context for every symlink in the cgroup tmpfs montpoint to
no longer have such warning.
Even if there is not FHS provision for this, systemd is using
/dev/hugepages to mount the hugetlbfs fs by default.
The needed file contexts are already present
Second part of the support of security_t under /sys/fs/selinux - when
asked not to audit getting attributes on the selinux file system, have
this propagate to the sysfs parts as well.
Signed-off-by: Sven Vermeulen <sven.vermeulen@siphos.be>
Because it is no longer a top-level file system, we need to enhance some
of the interfaces with the appropriate rights towards sysfs_t.
First set to allow getattr rights on the file system, which now also
means getattr on the sysfs_t file system as well as search privileges in
sysfs_t.
Signed-off-by: Sven Vermeulen <sven.vermeulen@siphos.be>
On Debian, this directory can contain locally trusted certificates that
will be then be symlinked to /etc/ssl/certs by
update-ca-certificates(8), the files should be labelled as cert_t.
The postgresql manpages are installed under a private directory, some of
them are symlinked to the usual location.
Properly labeling them ensure that mandb can read them.
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=740591
Associate the new xattrfs attribute to fs_t and the pseudo filesystems
that we know support xattr
This patch adds the attribute to the following (pseudo) filesystems
- device_t
- devpts_t
- fs_t
- hugetlbfs
- sysfs_t
- tmpfs_t
In glibc, the get_nprocs method reads /sys/devices/system/cpu/online, so
we need to grant most domains read access to this file. As we don't want
them to have read access on sysfs_t by default, create a new type
(cpu_online_t) and assign it to the file, and grant domains read access
to the file.
This does require systems to relabel the file upon every boot, something
distributions do in their bootup scripts, as /sys devices don't keep
their context.
Signed-off-by: Sven Vermeulen <sven.vermeulen@siphos.be>
When sudo is invoked (sudo -i) the audit log gets quite a lot of denials
related to the getattr permission against tty_device_t:chr_file for the
*_sudo_t domain. However, no additional logging (that would hint at a
need) by sudo, nor any functional issues come up.
Hence the dontaudit call.
Signed-off-by: Sven Vermeulen <sven.vermeulen@siphos.be>
Unprivileged users don't need to read kallsyms and /boot/System.map.
This allow rule was introduced in the initial revision of userdomain.if in
2005, with commit b16c6b8c32a631a2e66265f6f60b664222760972:
# cjp: why?
bootloader_read_kernel_symbol_table($1_t)
When working on fc_sort to try to understand why using /usr/s?bin/... file
contexts has been reported not to work properly [1], I found it frustrating not
to be able to do "tmp/fc_sort my_filecontexts.fc" and see the result printed on
the screen. This patch implements this behavior by making optional the second
argument of fc_sort.
[1] commit 36e2216f8 of contrib repository,
http://git.overlays.gentoo.org/gitweb/?p=proj/hardened-refpolicy.git;a=commit;h=36e2216f82192660d063012e69281f27ba20864b
When running fc_sort on an empty context file, this program uses uninitialized
pointers when accessing to the elements of a list. On my system, it goes in a
very long loop (maybe infinite) because uninitialized fields in malloc'ed
structures happen to contain valid pointers in the heap.
This patch fixes this bug by initializing ->next and ->data fields before they
may be read.
Before this commit, "make -j2" would execute twice at the same time the rules
written to build tmp/all_post.conf because these rules were applied every time
tmp/all_post.conf, tmp/all_attrs_types.conf and tmp/only_te_rules.conf needed
to be built. However, executing twice in parallel such line is buggy:
$(GREP) '^fs_use_(xattr|task|trans)' $(tmpdir)/all_te_files.conf >> \
tmpdir)/all_post.conf
This is why "make" reports following error for parallel builds:
Compiling refpolicy-patched base module
/usr/bin/checkmodule -M -U allow base.conf -o tmp/base.mod
/usr/bin/checkmodule: loading policy configuration from base.conf
policy/modules/kernel/ubac.te":710:ERROR 'syntax error' at token
'fs_use_trans' on line 26520:
fs_use_trans devtmpfs system_u:object_r:device_t:s0;
/usr/bin/checkmodule: error(s) encountered while parsing configuration
make: *** [tmp/base.mod] Error 1
This commit fixes this bug by splitting the rules in 3 different targets, in
both monolithic and modular builds.
Nicolas Iooss
Chris PeBenito
Laurent Bigonville
Sven Vermeulen
Luis Ressel
Chris PeBenito