selinux: avoid dereference of garbage after mount failure

In case kern_mount() fails and returns an error pointer return in the
error branch instead of continuing and dereferencing the error pointer.

While on it drop the never read static variable selinuxfs_mount.

Cc: stable@vger.kernel.org
Fixes: 0619f0f5e36f ("selinux: wrap selinuxfs state")
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: saner handling of policy reloads

On policy reload selinuxfs replaces two subdirectories (/booleans
and /class) with new variants. Unfortunately, that's done with
serious abuses of directory locking.

1) lock_rename() should be done to parents, not to objects being
exchanged

2) there's a bunch of reasons why it should not be done for directories
that do not have a common ancestor; most of those do not apply to
selinuxfs, but even in the best case the proof is subtle and brittle.

3) failure halfway through the creation of /class will leak
names and values arrays.

4) use of d_genocide() is also rather brittle; it's probably not much of
a bug per se, but e.g. an overmount of /sys/fs/selinuxfs/classes/shm/index
with any regular file will end up with leaked mount on policy reload.
Sure, don't do it, but...

Let's stop messing with disconnected directories; just create
a temporary (/.swapover) with no permissions for anyone (on the
level of ->permission() returing -EPERM, no matter who's calling
it) and build the new /booleans and /class in there; then
lock_rename on root and that temporary directory and d_exchange()
old and new both for class and booleans. Then unlock and use
simple_recursive_removal() to take the temporary out; it's much
more robust.

And instead of bothering with separate pathways for freeing
new (on failure halfway through) and old (on success) names/values,
do all freeing in one place. With temporaries swapped with the
old ones when we are past all possible failures.

The only user-visible difference is that /.swapover shows up
(but isn't possible to open, look up into, etc.) for the
duration of policy reload.

Reviewed-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[PM: applied some fixes from Al post merge]
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: convert to new timestamp accessors

Convert to using the new inode timestamp accessor functions.

Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20231004185347.80880-83-jlayton@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

selinux: avoid implicit conversions in selinuxfs code

Use umode_t as parameter type for sel_make_inode(), which assigns the
value to the member i_mode of struct inode.

Use identical and unsigned types for loop iterators.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: avoid implicit conversions in services code

Use u32 as the output parameter type in security_get_classes() and
security_get_permissions(), based on the type of the symtab nprim
member.

Declare the read-only class string parameter of
security_get_permissions() const.

Avoid several implicit conversions by using the identical type for the
destination.

Use the type identical to the source for local variables.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: cleanup extra whitespace in subject]
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: avoid implicit conversions regarding enforcing status

Use the type bool as parameter type in
selinux_status_update_setenforce(). The related function
enforcing_enabled() returns the type bool, while the struct
selinux_kernel_status member enforcing uses an u32.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: subject line tweaks]
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: convert to ctime accessor functions

In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-89-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

selinux: declare read-only data arrays const

The array of mount tokens in only used in match_opt_prefix() and never
modified.

The array of symtab names is never modified and only used in the
DEBUG_HASHES configuration as output.

The array of files for the SElinux filesystem sub-directory `ss` is
similar to the other `struct tree_descr` usages only read from to
construct the containing entries.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: adjust typos in comments

Found by codespell(1)

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: remove the runtime disable functionality

After working with the larger SELinux-based distros for several
years, we're finally at a place where we can disable the SELinux
runtime disable functionality. The existing kernel deprecation
notice explains the functionality and why we want to remove it:

The selinuxfs "disable" node allows SELinux to be disabled at
runtime prior to a policy being loaded into the kernel. If
disabled via this mechanism, SELinux will remain disabled until
the system is rebooted.

The preferred method of disabling SELinux is via the "selinux=0"
boot parameter, but the selinuxfs "disable" node was created to
make it easier for systems with primitive bootloaders that did not
allow for easy modification of the kernel command line.
Unfortunately, allowing for SELinux to be disabled at runtime makes
it difficult to secure the kernel's LSM hooks using the
"__ro_after_init" feature.

It is that last sentence, mentioning the '__ro_after_init' hardening,
which is the real motivation for this change, and if you look at the
diffstat you'll see that the impact of this patch reaches across all
the different LSMs, helping prevent tampering at the LSM hook level.

From a SELinux perspective, it is important to note that if you
continue to disable SELinux via "/etc/selinux/config" it may appear
that SELinux is disabled, but it is simply in an uninitialized state.
If you load a policy with `load_policy -i`, you will see SELinux
come alive just as if you had loaded the policy during early-boot.

It is also worth noting that the "/sys/fs/selinux/disable" file is
always writable now, regardless of the Kconfig settings, but writing
to the file has no effect on the system, other than to display an
error on the console if a non-zero/true value is written.

Finally, in the several years where we have been working on
deprecating this functionality, there has only been one instance of
someone mentioning any user visible breakage. In this particular
case it was an individual's kernel test system, and the workaround
documented in the deprecation notice ("selinux=0" on the kernel
command line) resolved the issue without problem.

Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: remove the 'checkreqprot' functionality

We originally promised that the SELinux 'checkreqprot' functionality
would be removed no sooner than June 2021, and now that it is March
2023 it seems like it is a good time to do the final removal. The
deprecation notice in the kernel provides plenty of detail on why
'checkreqprot' is not desirable, with the key point repeated below:

This was a compatibility mechanism for legacy userspace and
for the READ_IMPLIES_EXEC personality flag. However, if set to
1, it weakens security by allowing mappings to be made executable
without authorization by policy. The default value of checkreqprot
at boot was changed starting in Linux v4.4 to 0 (i.e. check the
actual protection), and Android and Linux distributions have been
explicitly writing a "0" to /sys/fs/selinux/checkreqprot during
initialization for some time.

Along with the official deprecation notice, we have been discussing
this on-list and directly with several of the larger SELinux-based
distros and everyone is happy to see this feature finally removed.
In an attempt to catch all of the smaller, and DIY, Linux systems
we have been writing a deprecation notice URL into the kernel log,
along with a growing ssleep() penalty, when admins enabled
checkreqprot at runtime or via the kernel command line. We have
yet to have anyone come to us and raise an objection to the
deprecation or planned removal.

It is worth noting that while this patch removes the checkreqprot
functionality, it leaves the user visible interfaces (kernel command
line and selinuxfs file) intact, just inert. This should help
prevent breakages with existing userspace tools that correctly, but
unnecessarily, disable checkreqprot at boot or runtime. Admins
that attempt to enable checkreqprot will be met with a removal
message in the kernel log.

Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: stop passing selinux_state pointers and their offspring

Linus observed that the pervasive passing of selinux_state pointers
introduced by me in commit aa8e712cee93 ("selinux: wrap global selinux
state") adds overhead and complexity without providing any
benefit. The original idea was to pave the way for SELinux namespaces
but those have not yet been implemented and there isn't currently
a concrete plan to do so. Remove the passing of the selinux_state
pointers, reverting to direct use of the single global selinux_state,
and likewise remove passing of child pointers like the selinux_avc.
The selinux_policy pointer remains as it is needed for atomic switching
of policies.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202303101057.mZ3Gv5fK-lkp@intel.com/
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

mm: replace vma->vm_flags direct modifications with modifier calls

Replace direct modifications to vma->vm_flags with calls to modifier
functions to be able to track flag changes and to keep vma locking
correctness.

[akpm@linux-foundation.org: fix drivers/misc/open-dice.c, per Hyeonggon Yoo]
Link: https://lkml.kernel.org/r/20230126193752.297968-5-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjun Roy <arjunroy@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Minchan Kim <minchan@google.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Oskolkov <posk@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Punit Agrawal <punit.agrawal@bytedance.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

selinux: increase the deprecation sleep for checkreqprot and runtime disable

Further the checkreqprot and runtime disable deprecation efforts by
increasing the sleep time from 5 to 15 seconds to help make this more
noticeable for any users who are still using these knobs.

Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: use int arrays for boolean values

Do not cast pointers of signed integers to pointers of unsigned integers
and vice versa.

It should currently not be an issue since they hold SELinux boolean
values which should only contain either 0's or 1's, which should have
the same representation.

Reported by sparse:

.../selinuxfs.c:1485:30: warning: incorrect type in assignment
(different signedness)
.../selinuxfs.c:1485:30: expected unsigned int *
.../selinuxfs.c:1485:30: got int *[addressable] values
.../selinuxfs.c:1402:48: warning: incorrect type in argument 3
(different signedness)
.../selinuxfs.c:1402:48: expected int *values
.../selinuxfs.c:1402:48: got unsigned int *bool_pending_values

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: minor whitespace fixes, sparse output cleanup]
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: remove an unneeded variable in sel_make_class_dir_entries()

Return the value sel_make_perm_files() directly instead of storing it
in another redundant variable.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
[PM: subject line tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: don't sleep when CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE is true

Unfortunately commit 81200b0265b1 ("selinux: checkreqprot is
deprecated, add some ssleep() discomfort") added a five second sleep
during early kernel boot, e.g. start_kernel(), which could cause a
"scheduling while atomic" panic. This patch fixes this problem by
moving the sleep out of checkreqprot_set() and into
sel_write_checkreqprot() so that we only sleep when the checkreqprot
setting is set during runtime, after the kernel has booted. The
error message remains the same in both cases.

Fixes: 81200b0265b1 ("selinux: checkreqprot is deprecated, add some ssleep() discomfort")
Reported-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: checkreqprot is deprecated, add some ssleep() discomfort

The checkreqprot functionality was disabled by default back in
Linux v4.4 (2015) with commit 2a35d196c160e3 ("selinux: change
CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE default") and it was
officially marked as deprecated in Linux v5.7. It was always a
bit of a hack to workaround very old userspace and to the best of
our knowledge, the checkreqprot functionality has been disabled by
Linux distributions for quite some time.

This patch moves the deprecation messages from KERN_WARNING to
KERN_ERR and adds a five second sleep to anyone using it to help
draw their attention to the deprecation and provide a URL which
helps explain things in more detail.

Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: runtime disable is deprecated, add some ssleep() discomfort

We deprecated the SELinux runtime disable functionality in Linux
v5.6, and it is time to get a bit more serious about removing it.
Add a five second sleep to anyone using it to help draw their
attention to the deprecation and provide a URL which helps explain
things in more detail, including how to add kernel command line
parameters to some of the more popular Linux distributions.

Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: shorten the policy capability enum names

The SELinux policy capability enum names are rather long and follow
the "POLICYDB_CAPABILITY_XXX format". While the "POLICYDB_" prefix
is helpful in tying the enums to other SELinux policy constants,
macros, etc. there is no reason why we need to spell out
"CAPABILITY" completely. Shorten "CAPABILITY" to "CAP" in order to
make things a bit shorter and cleaner.

Moving forward, the SELinux policy capability enum names should
follow the "POLICYDB_CAP_XXX" format.

Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: check return value of sel_make_avc_files

sel_make_avc_files() might fail and return a negative errno value on
memory allocation failures. Re-add the check of the return value,
dropped in 66f8e2f03c02 ("selinux: sidtab reverse lookup hash table").

Reported by clang-analyzer:

security/selinux/selinuxfs.c:2129:2: warning: Value stored to
'ret' is never read [deadcode.DeadStores]
ret = sel_make_avc_files(dentry);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~

Fixes: 66f8e2f03c02 ("selinux: sidtab reverse lookup hash table")
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
[PM: description line wrapping, added proper commit ref]
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: measure state and policy capabilities

SELinux stores the configuration state and the policy capabilities
in kernel memory. Changes to this data at runtime would have an impact
on the security guarantees provided by SELinux. Measuring this data
through IMA subsystem provides a tamper-resistant way for
an attestation service to remotely validate it at runtime.

Measure the configuration state and policy capabilities by calling
the IMA hook ima_measure_critical_data().

To enable SELinux data measurement, the following steps are required:

1, Add "ima_policy=critical_data" to the kernel command line arguments
to enable measuring SELinux data at boot time.
For example,
BOOT_IMAGE=/boot/vmlinuz-5.11.0-rc3+ root=UUID=fd643309-a5d2-4ed3-b10d-3c579a5fab2f ro nomodeset security=selinux ima_policy=critical_data

2, Add the following rule to /etc/ima/ima-policy
measure func=CRITICAL_DATA label=selinux

Sample measurement of SELinux state and policy capabilities:

10 2122...65d8 ima-buf sha256:13c2...1292 selinux-state 696e...303b

Execute the following command to extract the measured data
from the IMA's runtime measurements list:

grep "selinux-state" /sys/kernel/security/integrity/ima/ascii_runtime_measurements | tail -1 | cut -d' ' -f 6 | xxd -r -p

The output should be a list of key-value pairs. For example,
initialized=1;enforcing=0;checkreqprot=1;network_peer_controls=1;open_perms=1;extended_socket_class=1;always_check_network=0;cgroup_seclabel=1;nnp_nosuid_transition=1;genfs_seclabel_symlinks=0;

To verify the measurement is consistent with the current SELinux state
reported on the system, compare the integer values in the following
files with those set in the IMA measurement (using the following commands):

- cat /sys/fs/selinux/enforce
- cat /sys/fs/selinux/checkreqprot
- cat /sys/fs/selinux/policy_capabilities/[capability_file]

Note that the actual verification would be against an expected state
and done on a separate system (likely an attestation server) requiring
"initialized=1;enforcing=1;checkreqprot=0;"
for a secure state and then whatever policy capabilities are actually
set in the expected policy (which can be extracted from the policy
itself via seinfo, for example).

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Suggested-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinuxfs: unify policy load error reporting

Let's drop the pr_err()s from sel_make_policy_nodes() and just add one
pr_warn_ratelimited() call to the sel_make_policy_nodes() error path in
sel_write_load().

Changing from error to warning makes sense, since after 02a52c5c8c3b
("selinux: move policy commit after updating selinuxfs"), this error
path no longer leads to a broken selinuxfs tree (it's just kept in the
original state and policy load is aborted).

I also added _ratelimited to be consistent with the other prtin in the
same function (it's probably not necessary, but can't really hurt...
there are likely more important error messages to be printed when
filesystem entry creation starts erroring out).

Suggested-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: fix variable scope issue in live sidtab conversion

Commit 02a52c5c8c3b ("selinux: move policy commit after updating
selinuxfs") moved the selinux_policy_commit() call out of
security_load_policy() into sel_write_load(), which caused a subtle yet
rather serious bug.

The problem is that security_load_policy() passes a reference to the
convert_params local variable to sidtab_convert(), which stores it in
the sidtab, where it may be accessed until the policy is swapped over
and RCU synchronized. Before 02a52c5c8c3b, selinux_policy_commit() was
called directly from security_load_policy(), so the convert_params
pointer remained valid all the way until the old sidtab was destroyed,
but now that's no longer the case and calls to sidtab_context_to_sid()
on the old sidtab after security_load_policy() returns may cause invalid
memory accesses.

This can be easily triggered using the stress test from commit
ee1a84fdfeed ("selinux: overhaul sidtab to fix bug and improve
performance"):
```
function rand_cat() {
echo $(( $RANDOM % 1024 ))
}

function do_work() {
while true; do
echo -n "system_u:system_r:kernel_t:s0:c$(rand_cat),c$(rand_cat)" \
>/sys/fs/selinux/context 2>/dev/null || true
done
}

do_work >/dev/null &
do_work >/dev/null &
do_work >/dev/null &

while load_policy; do echo -n .; sleep 0.1; done

kill %1
kill %2
kill %3
```

Fix this by allocating the temporary sidtab convert structures
dynamically and passing them among the
selinux_policy_{load,cancel,commit} functions.

Fixes: 02a52c5c8c3b ("selinux: move policy commit after updating selinuxfs")
Cc: stable@vger.kernel.org
Tested-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
[PM: merge fuzz in security.h and services.c]
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: don't log MAC_POLICY_LOAD record on failed policy load

If sel_make_policy_nodes() fails, we should jump to 'out', not 'out1',
as the latter would incorrectly log an MAC_POLICY_LOAD audit record,
even though the policy hasn't actually been reloaded. The 'out1' jump
label now becomes unused and can be removed.

Fixes: 02a52c5c8c3b ("selinux: move policy commit after updating selinuxfs")
Cc: stable@vger.kernel.org
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: mark some global variables __ro_after_init

All of these are never modified outside initcalls, so they can be
__ro_after_init.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: make selinuxfs_mount static

It is not referenced outside selinuxfs.c, so remove its extern header
declaration and make it static.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: Add helper functions to get and set checkreqprot

checkreqprot data member in selinux_state struct is accessed directly by
SELinux functions to get and set. This could cause unexpected read or
write access to this data member due to compiler optimizations and/or
compiler's reordering of access to this field.

Add helper functions to get and set checkreqprot data member in
selinux_state struct. These helper functions use READ_ONCE and
WRITE_ONCE macros to ensure atomic read or write of memory for
this data member.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Suggested-by: Paul Moore <paul@paul-moore.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: simplify away security_policydb_len()

Remove the security_policydb_len() calls from sel_open_policy() and
instead update the inode size from the size returned from
security_read_policy().

Since after this change security_policydb_len() is only called from
security_load_policy(), remove it entirely and just open-code it there.

Also, since security_load_policy() is always called with policy_mutex
held, make it dereference the policy pointer directly and drop the
unnecessary RCU locking.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: move policy mutex to selinux_state, use in lockdep checks

Move the mutex used to synchronize policy changes (reloads and setting
of booleans) from selinux_fs_info to selinux_state and use it in
lockdep checks for rcu_dereference_protected() calls in the security
server functions. This makes the dependency on the mutex explicit
in the code rather than relying on comments.

Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: Create new booleans and class dirs out of tree

In order to avoid concurrency issues around selinuxfs resource availability
during policy load, we first create new directories out of tree for
reloaded resources, then swap them in, and finally delete the old versions.

This fix focuses on concurrency in each of the two subtrees swapped, and
not concurrency between the trees. This means that it is still possible
that subsequent reads to eg the booleans directory and the class directory
during a policy load could see the old state for one and the new for the other.
The problem of ensuring that policy loads are fully atomic from the perspective
of userspace is larger than what is dealt with here. This commit focuses on
ensuring that the directories contents always match either the new or the old
policy state from the perspective of userspace.

In the previous implementation, on policy load /sys/fs/selinux is updated
by deleting the previous contents of
/sys/fs/selinux/{class,booleans} and then recreating them. This means
that there is a period of time when the contents of these directories do not
exist which can cause race conditions as userspace relies on them for
information about the policy. In addition, it means that error recovery in
the event of failure is challenging.

In order to demonstrate the race condition that this series fixes, you
can use the following commands:

while true; do cat /sys/fs/selinux/class/service/perms/status
>/dev/null; done &
while true; do load_policy; done;

In the existing code, this will display errors fairly often as the class
lookup fails. (In normal operation from systemd, this would result in a
permission check which would be allowed or denied based on policy settings
around unknown object classes.) After applying this patch series you
should expect to no longer see such error messages.

Signed-off-by: Daniel Burgener <dburgener@linux.microsoft.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: Standardize string literal usage for selinuxfs directory names

Switch class and policy_capabilities directory names to be referred to with
global constants, consistent with booleans directory name. This will allow
for easy consistency of naming in future development.

Signed-off-by: Daniel Burgener <dburgener@linux.microsoft.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: Refactor selinuxfs directory populating functions

Make sel_make_bools and sel_make_classes take the specific elements of
selinux_fs_info that they need rather than the entire struct.

This will allow a future patch to pass temporary elements that are not in
the selinux_fs_info struct to these functions so that the original elements
can be preserved until we are ready to perform the switch over.

Signed-off-by: Daniel Burgener <dburgener@linux.microsoft.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: Create function for selinuxfs directory cleanup

Separating the cleanup from the creation will simplify two things in
future patches in this series. First, the creation can be made generic,
to create directories not tied to the selinux_fs_info structure. Second,
we will ultimately want to reorder creation and deletion so that the
deletions aren't performed until the new directory structures have already
been moved into place.

Signed-off-by: Daniel Burgener <dburgener@linux.microsoft.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: move policy commit after updating selinuxfs

With the refactoring of the policy load logic in the security
server from the previous change, it is now possible to split out
the committing of the new policy from security_load_policy() and
perform it only after successful updating of selinuxfs. Change
security_load_policy() to return the newly populated policy
data structures to the caller, export selinux_policy_commit()
for external callers, and introduce selinux_policy_cancel() to
provide a way to cancel the policy load in the event of an error
during updating of the selinuxfs directory tree. Further, rework
the interfaces used by selinuxfs to get information from the policy
when creating the new directory tree to take and act upon the
new policy data structure rather than the current/active policy.
Update selinuxfs to use these updated and new interfaces. While
we are here, stop re-creating the policy_capabilities directory
on each policy load since it does not depend on the policy, and
stop trying to create the booleans and classes directories during
the initial creation of selinuxfs since no information is available
until first policy load.

After this change, a failure while updating the booleans and class
directories will cause the entire policy load to be canceled, leaving
the original policy intact, and policy load notifications to userspace
will only happen after a successful completion of updating those
directories. This does not (yet) provide full atomicity with respect
to the updating of the directory trees themselves.

Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: remove unused initial SIDs and improve handling

Remove initial SIDs that have never been used or are no longer used by
the kernel from its string table, which is also used to generate the
SECINITSID_* symbols referenced in code. Update the code to
gracefully handle the fact that these can now be NULL. Stop treating
it as an error if a policy defines additional initial SIDs unknown to
the kernel. Do not load unused initial SID contexts into the sidtab.
Fix the incorrect usage of the name from the ocontext in error
messages when loading initial SIDs since these are not presently
written to the kernel policy and are therefore always NULL.

After this change, it is possible to safely reclaim and reuse some of
the unused initial SIDs without compatibility issues. Specifically,
unused initial SIDs that were being assigned the same context as the
unlabeled initial SID in policies can be reclaimed and reused for
another purpose, with existing policies still treating them as having
the unlabeled context and future policies having the option of mapping
them to a more specific context. For example, this could have been
used when the infiniband labeling support was introduced to define
initial SIDs for the default pkey and endport SIDs similar to the
handling of port/netif/node SIDs rather than always using
SECINITSID_UNLABELED as the default.

The set of safely reclaimable unused initial SIDs across all known
policies is igmp_packet (13), icmp_socket (14), tcp_socket (15), kmod
(24), policy (25), and scmp_packet (26); these initial SIDs were
assigned the same context as unlabeled in all known policies including
mls. If only considering non-mls policies (i.e. assuming that mls
users always upgrade policy with their kernels), the set of safely
reclaimable unused initial SIDs further includes file_labels (6), init
(7), sysctl_modprobe (16), and sysctl_fs (18) through sysctl_dev (23).

Adding new initial SIDs beyond SECINITSID_NUM to policy unfortunately
became a fatal error in commit 24ed7fdae669 ("selinux: use separate
table for initial SID lookup") and even before that it could cause
problems on a policy reload (collision between the new initial SID and
one allocated at runtime) ever since commit 42596eafdd75 ("selinux:
load the initial SIDs upon every policy load") so we cannot safely
start adding new initial SIDs to policies beyond SECINITSID_NUM (27)
until such a time as all such kernels do not need to be supported and
only those that include this commit are relevant. That is not a big
deal since we haven't added a new initial SID since 2004 (v2.6.7) and
we have plenty of unused ones we can reclaim if we truly need one.

If we want to avoid the wasted storage in initial_sid_to_string[]
and/or sidtab->isids[] for the unused initial SIDs, we could introduce
an indirection between the kernel initial SID values and the policy
initial SID values and just map the policy SID values in the ocontexts
to the kernel values during policy_load_isids(). Originally I thought
we'd do this by preserving the initial SID names in the kernel policy
and creating a mapping at load time like we do for the security
classes and permissions but that would require a new kernel policy
format version and associated changes to libsepol/checkpolicy and I'm
not sure it is justified. Simpler approach is just to create a fixed
mapping table in the kernel from the existing fixed policy values to
the kernel values. Less flexible but probably sufficient.

A separate selinux userspace change was applied in
https://github.com/SELinuxProject/selinux/commit/8677ce5e8f592950ae6f14cea1b68a20ddc1ac25
to enable removal of most of the unused initial SID contexts from
policies, but there is no dependency between that change and this one.
That change permits removing all of the unused initial SID contexts
from policy except for the fs and sysctl SID contexts. The initial
SID declarations themselves would remain in policy to preserve the
values of subsequent ones but the contexts can be dropped. If/when
the kernel decides to reuse one of them, future policies can change
the name and start assigning a context again without breaking
compatibility.

Here is how I would envision staging changes to the initial SIDs in a
compatible manner after this commit is applied:

1. At any time after this commit is applied, the kernel could choose
to reclaim one of the safely reclaimable unused initial SIDs listed
above for a new purpose (i.e. replace its NULL entry in the
initial_sid_to_string[] table with a new name and start using the
newly generated SECINITSID_name symbol in code), and refpolicy could
at that time rename its declaration of that initial SID to reflect its
new purpose and start assigning it a context going
forward. Existing/old policies would map the reclaimed initial SID to
the unlabeled context, so that would be the initial default behavior
until policies are updated. This doesn't depend on the selinux
userspace change; it will work with existing policies and userspace.

2. In 6 months or so we'll have another SELinux userspace release that
will include the libsepol/checkpolicy support for omitting unused
initial SID contexts.

3. At any time after that release, refpolicy can make that release its
minimum build requirement and drop the sid context statements (but not
the sid declarations) for all of the unused initial SIDs except for
fs and sysctl, which must remain for compatibility on policy
reload with old kernels and for compatibility with kernels that were
still using SECINITSID_SYSCTL (< 2.6.39). This doesn't depend on this
kernel commit; it will work with previous kernels as well.

4. After N years for some value of N, refpolicy decides that it no
longer cares about policy reload compatibility for kernels that
predate this kernel commit, and refpolicy drops the fs and sysctl
SID contexts from policy too (but retains the declarations).

5. After M years for some value of M, the kernel decides that it no
longer cares about compatibility with refpolicies that predate step 4
(dropping the fs and sysctl SIDs), and those two SIDs also become
safely reclaimable. This step is optional and need not ever occur unless
we decide that the need to reclaim those two SIDs outweighs the
compatibility cost.

6. After O years for some value of O, refpolicy decides that it no
longer cares about policy load (not just reload) compatibility for
kernels that predate this kernel commit, and both kernel and refpolicy
can then start adding and using new initial SIDs beyond 27. This does
not depend on the previous change (step 5) and can occur independent
of it.

Fixes: https://github.com/SELinuxProject/selinux-kernel/issues/12
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: convert cond_list to array

Since it is fixed-size after allocation and we know the size beforehand,
using a plain old array is simpler and more efficient.

While there, also fix signedness of some related variables/parameters.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: sel_avc_get_stat_idx should increase position index

If seq_file .next function does not change position index,
read after some lseek can generate unexpected output.

$ dd if=/sys/fs/selinux/avc/cache_stats # usual output
lookups hits misses allocations reclaims frees
817223 810034 7189 7189 6992 7037
1934894 1926896 7998 7998 7632 7683
1322812 1317176 5636 5636 5456 5507
1560571 1551548 9023 9023 9056 9115
0+1 records in
0+1 records out
189 bytes copied, 5,1564e-05 s, 3,7 MB/s

$# read after lseek to midle of last line
$ dd if=/sys/fs/selinux/avc/cache_stats bs=180 skip=1
dd: /sys/fs/selinux/avc/cache_stats: cannot skip to specified offset
056 9115 <<<< end of last line
1560571 1551548 9023 9023 9056 9115 <<< whole last line once again
0+1 records in
0+1 records out
45 bytes copied, 8,7221e-05 s, 516 kB/s

$# read after lseek beyond end of of file
$ dd if=/sys/fs/selinux/avc/cache_stats bs=1000 skip=1
dd: /sys/fs/selinux/avc/cache_stats: cannot skip to specified offset
1560571 1551548 9023 9023 9056 9115 <<<< generates whole last line
0+1 records in
0+1 records out
36 bytes copied, 9,0934e-05 s, 396 kB/s

https://bugzilla.kernel.org/show_bug.cgi?id=206283

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>

Documentation,selinux: deprecate setting checkreqprot to 1

Deprecate setting the SELinux checkreqprot tunable to 1 via kernel
parameter or /sys/fs/selinux/checkreqprot. Setting it to 0 is left
intact for compatibility since Android and some Linux distributions
do so for security and treat an inability to set it as a fatal error.
Eventually setting it to 0 will become a no-op and the kernel will
stop using checkreqprot's value internally altogether.

checkreqprot was originally introduced as a compatibility mechanism
for legacy userspace and the READ_IMPLIES_EXEC personality flag.
However, if set to 1, it weakens security by allowing mappings to be
made executable without authorization by policy. The default value
for the SECURITY_SELINUX_CHECKREQPROT_VALUE config option was changed
from 1 to 0 in commit 2a35d196c160e3 ("selinux: change
CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE default") and both Android
and Linux distributions began explicitly setting
/sys/fs/selinux/checkreqprot to 0 some time ago.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: deprecate disabling SELinux and runtime

Deprecate the CONFIG_SECURITY_SELINUX_DISABLE functionality. The
code was originally developed to make it easier for Linux
distributions to support architectures where adding parameters to the
kernel command line was difficult. Unfortunately, supporting runtime
disable meant we had to make some security trade-offs when it came to
the LSM hooks, as documented in the Kconfig help text:

NOTE: selecting this option will disable the '__ro_after_init'
kernel hardening feature for security hooks. Please consider
using the selinux=0 boot parameter instead of enabling this
option.

Fortunately it looks as if that the original motivation for the
runtime disable functionality is gone, and Fedora/RHEL appears to be
the only major distribution enabling this capability at build time
so we are now taking steps to remove it entirely from the kernel.
The first step is to mark the functionality as deprecated and print
an error when it is used (what this patch is doing). As Fedora/RHEL
makes progress in transitioning the distribution away from runtime
disable, we will introduce follow-up patches over several kernel
releases which will block for increasing periods of time when the
runtime disable is used. Finally we will remove the option entirely
once we believe all users have moved to the kernel cmdline approach.

Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinuxfs: use scnprintf to get real length for inode

The return value of snprintf maybe over the size of TMPBUFLEN, use
scnprintf instead in sel_read_class and sel_read_perm.

Signed-off-by: liuyang34 <liuyang34@xiaomi.com>
[PM: cleaned up the description]
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: clean up selinux_enabled/disabled/enforcing_boot

Rename selinux_enabled to selinux_enabled_boot to make it clear that
it only reflects whether SELinux was enabled at boot. Replace the
references to it in the MAC_STATUS audit log in sel_write_enforce()
with hardcoded "1" values because this code is only reachable if SELinux
is enabled and does not change its value, and update the corresponding
MAC_STATUS audit log in sel_write_disable(). Stop clearing
selinux_enabled in selinux_disable() since it is not used outside of
initialization code that runs before selinux_disable() can be reached.
Mark both selinux_enabled_boot and selinux_enforcing_boot as __initdata
since they are only used in initialization code.

Wrap the disabled field in the struct selinux_state with
CONFIG_SECURITY_SELINUX_DISABLE since it is only used for
runtime disable.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: sidtab reverse lookup hash table

This replaces the reverse table lookup and reverse cache with a
hashtable which improves cache-miss reverse-lookup times from
O(n) to O(1)* and maintains the same performance as a reverse
cache hit.

This reduces the time needed to add a new sidtab entry from ~500us
to 5us on a Pixel 3 when there are ~10,000 sidtab entries.

The implementation uses the kernel's generic hashtable API,
It uses the context's string represtation as the hash source,
and the kernels generic string hashing algorithm full_name_hash()
to reduce the string to a 32 bit value.

This change also maintains the improvement introduced in
commit ee1a84fdfeed ("selinux: overhaul sidtab to fix bug and improve
performance") which removed the need to keep the current sidtab
locked during policy reload. It does however introduce periodic
locking of the target sidtab while converting the hashtable. Sidtab
entries are never modified or removed, so the context struct stored
in the sid_to_context tree can also be used for the context_to_sid
hashtable to reduce memory usage.

This bug was reported by:
- On the selinux bug tracker.
BUG: kernel softlockup due to too many SIDs/contexts #37
https://github.com/SELinuxProject/selinux-kernel/issues/37
- Jovana Knezevic on Android's bugtracker.
Bug: 140252993
"During multi-user performance testing, we create and remove users
many times. selinux_android_restorecon_pkgdir goes from 1ms to over
20ms after about 200 user creations and removals. Accumulated over
~280 packages, that adds a significant time to user creation,
making perf benchmarks unreliable."

* Hashtable lookup is only O(1) when n < the number of buckets.

Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Reported-by: Stephen Smalley <sds@tycho.nsa.gov>
Reported-by: Jovana Knezevic <jovanak@google.com>
Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
Tested-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: subj tweak, removed changelog from patch description]
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: remove load size limit

Load size was limited to 64MB, this was legacy limitation due to vmalloc()
which was removed a while ago.

Signed-off-by: zhanglin <zhang.lin16@zte.com.cn>
[PM: removed comments in the description about 'real world use cases']
Signed-off-by: Paul Moore <paul@paul-moore.com>

vfs: Convert selinuxfs to use the new mount API

Convert the selinuxfs filesystem to the new internal mount API as the old
one will be obsoleted and removed. This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Paul Moore <paul@paul-moore.com>
cc: Stephen Smalley <sds@tycho.nsa.gov>
cc: Eric Paris <eparis@parisplace.org>
cc: selinux@vger.kernel.org
cc: linux-security-module@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

LSM: switch to blocking policy update notifiers

Atomic policy updaters are not very useful as they cannot
usually perform the policy updates on their own. Since it
seems that there is no strict need for the atomicity,
switch to the blocking variant. While doing so, rename
the functions accordingly.

Signed-off-by: Janne Karhunen <janne.karhunen@gmail.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 372

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 135 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531081036.435762997@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

SELinux: Abstract use of inode security blob

Don't use the inode->i_security pointer directly.
Provide a helper function that provides the security blob pointer.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>

selinux: cleanup dentry and inodes on error in selinuxfs

If the resource requested by d_alloc_name is not added to the linked
list through d_add, then dput needs to be called to release the
subsequent abnormal branch to avoid resource leakage.

Add missing dput to selinuxfs.c

Signed-off-by: nixiaoming <nixiaoming@huawei.com>
[PM: tweak the subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: constify write_op[]

write_op[] is never modified, so make it 'const'.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: move user accesses in selinuxfs out of locked regions

If a user is accessing a file in selinuxfs with a pointer to a userspace
buffer that is backed by e.g. a userfaultfd, the userspace access can
stall indefinitely, which can block fsi->mutex if it is held.

For sel_read_policy(), remove the locking, since this method doesn't seem
to access anything that requires locking.

For sel_read_bool(), move the user access below the locked region.

For sel_write_bool() and sel_commit_bools_write(), move the user access
up above the locked region.

Cc: stable@vger.kernel.org
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: removed an unused variable in sel_read_policy()]
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: Cleanup printk logging in selinuxfs

Replace printk with pr_* to avoid checkpatch warnings.

Signed-off-by: Peter Enderborg <peter.enderborg@sony.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

audit: use inline function to get audit context

Recognizing that the audit context is an internal audit value, use an
access function to retrieve the audit context pointer for the task
rather than reaching directly into the task struct to get it.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: merge fuzz in auditsc.c and selinuxfs.c, checkpatch.pl fixes]
Signed-off-by: Paul Moore <paul@paul-moore.com>

audit: normalize MAC_POLICY_LOAD record

The audit MAC_POLICY_LOAD record had redundant dangling keywords and was
missing information about which LSM was responsible and its completion
status. While this record is only issued on success, the parser expects
the res= field to be present.

Old record:
type=MAC_POLICY_LOAD msg=audit(1479299795.404:43): policy loaded auid=0 ses=1

Delete the redundant dangling keywords, add the lsm= field and the res=
field.

New record:
type=MAC_POLICY_LOAD msg=audit(1523293846.204:894): auid=0 ses=1 lsm=selinux res=1

See: https://github.com/linux-audit/audit-kernel/issues/47

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

audit: normalize MAC_STATUS record

There were two formats of the audit MAC_STATUS record, one of which was more
standard than the other. One listed enforcing status changes and the
other listed enabled status changes with a non-standard label. In
addition, the record was missing information about which LSM was
responsible and the operation's completion status. While this record is
only issued on success, the parser expects the res= field to be present.

old enforcing/permissive:
type=MAC_STATUS msg=audit(1523312831.378:24514): enforcing=0 old_enforcing=1 auid=0 ses=1
old enable/disable:
type=MAC_STATUS msg=audit(1523312831.378:24514): selinux=0 auid=0 ses=1

List both sets of status and old values and add the lsm= field and the
res= field.

Here is the new format:
type=MAC_STATUS msg=audit(1523293828.657:891): enforcing=0 old_enforcing=1 auid=0 ses=1 enabled=1 old-enabled=1 lsm=selinux res=1

This record already accompanied a SYSCALL record.

See: https://github.com/linux-audit/audit-kernel/issues/46

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: 80-char fixes, merge fuzz, use new SELinux state functions]
Signed-off-by: Paul Moore <paul@paul-moore.com>

security: selinux: Change return type to vm_fault_t

Use new return type vm_fault_t for fault handler
in struct vm_operations_struct.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: fix missing dput() before selinuxfs unmount

Commit 0619f0f5e36f ("selinux: wrap selinuxfs state") triggers a BUG
when SELinux is runtime-disabled (i.e. systemd or equivalent disables
SELinux before initial policy load via /sys/fs/selinux/disable based on
/etc/selinux/config SELINUX=disabled).

This does not manifest if SELinux is disabled via kernel command line
argument or if SELinux is enabled (permissive or enforcing).

Before:
SELinux: Disabled at runtime.
BUG: Dentry 000000006d77e5c7{i=17,n=null} still in use (1) [unmount of selinuxfs selinuxfs]

After:
SELinux: Disabled at runtime.

Fixes: 0619f0f5e36f ("selinux: wrap selinuxfs state")
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selinux: wrap AVC state

Wrap the AVC state within the selinux_state structure and
pass it explicitly to all AVC functions. The AVC private state
is encapsulated in a selinux_avc structure that is referenced
from the selinux_state.

This change should have no effect on SELinux behavior or
APIs (userspace or LSM).

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: James Morris <james.morris@microsoft.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: wrap selinuxfs state

Move global selinuxfs state to a per-instance structure (selinux_fs_info),
and include a pointer to the selinux_state in this structure.
Pass this selinux_state to all security server operations, thereby
ensuring that each selinuxfs instance presents a view of and acts
as an interface to a particular selinux_state instance.

This change should have no effect on SELinux behavior or APIs
(userspace or LSM). It merely wraps the selinuxfs global state,
links it to a particular selinux_state (currently always the single
global selinux_state) and uses that state for all operations.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: rename the {is,set}_enforcing() functions

Rename is_enforcing() to enforcing_enabled() and
enforcing_set() to set_enforcing().

Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: wrap global selinux state

Define a selinux state structure (struct selinux_state) for
global SELinux state and pass it explicitly to all security server
functions. The public portion of the structure contains state
that is used throughout the SELinux code, such as the enforcing mode.
The structure also contains a pointer to a selinux_ss structure whose
definition is private to the security server and contains security
server specific state such as the policy database and SID table.

This change should have no effect on SELinux behavior or APIs
(userspace or LSM). It merely wraps SELinux state and passes it
explicitly as needed.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: minor fixups needed due to collisions with the SCTP patches]
Signed-off-by: Paul Moore <paul@paul-moore.com>

sel_write_validatetrans(): don't open-code memdup_user_nul()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

selinux lsm IB/core: Implement LSM notification system

Add a generic notificaiton mechanism in the LSM. Interested consumers
can register a callback with the LSM and security modules can produce
events.

Because access to Infiniband QPs are enforced in the setup phase of a
connection security should be enforced again if the policy changes.
Register infiniband devices for policy change notification and check all
QPs on that device when the notification is received.

Add a call to the notification mechanism from SELinux when the AVC
cache changes or setenforce is cleared.

Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Acked-by: James Morris <james.l.morris@oracle.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: log policy capability state when a policy is loaded

Log the state of SELinux policy capabilities when a policy is loaded.
For each policy capability known to the kernel, log the policy capability
name and the value set in the policy. For policy capabilities that are
set in the loaded policy but unknown to the kernel, log the policy
capability index, since this is the only information presently available
in the policy.

Sample output with a policy created with a new capability defined
that is not known to the kernel:
SELinux: policy capability network_peer_controls=1
SELinux: policy capability open_perms=1
SELinux: policy capability extended_socket_class=1
SELinux: policy capability always_check_network=0
SELinux: policy capability cgroup_seclabel=0
SELinux: unknown policy capability 5

Resolves: https://github.com/SELinuxProject/selinux-kernel/issues/32

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>

fs: constify tree_descr arrays passed to simple_fill_super()

simple_fill_super() is passed an array of tree_descr structures which
describe the files to create in the filesystem's root directory. Since
these arrays are never modified intentionally, they should be 'const' so
that they are placed in .rodata and benefit from memory protection.
This patch updates the function signature and all users, and also
constifies tree_descr.name.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

selinuxfs: Use seq_puts() in sel_avc_stats_seq_show()

A string which did not contain data format specifications should be put
into a sequence. Thus use the corresponding function "seq_puts".

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: wrap cgroup seclabel support with its own policy capability

commit 1ea0ce40690dff38935538e8dab7b12683ded0d3 ("selinux: allow
changing labels for cgroupfs") broke the Android init program,
which looks up security contexts whenever creating directories
and attempts to assign them via setfscreatecon().
When creating subdirectories in cgroup mounts, this would previously
be ignored since cgroup did not support userspace setting of security
contexts. However, after the commit, SELinux would attempt to honor
the requested context on cgroup directories and fail due to permission
denial. Avoid breaking existing userspace/policy by wrapping this change
with a conditional on a new cgroup_seclabel policy capability. This
preserves existing behavior until/unless a new policy explicitly enables
this capability.

Reported-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf

->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to
take a vma and vmf parameter when the vma already resides in vmf.

Remove the vma parameter to simplify things.

[arnd@arndb.de: fix ARM build]
Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selinux: default to security isid in sel_make_bools() if no sid is found

Use SECINITSID_SECURITY as the default SID for booleans which don't have
a matching SID returned from security_genfs_sid(), also update the
error message to a warning which matches this.

This prevents the policy failing to load (and consequently the system
failing to boot) when there is no default genfscon statement matched for
the selinuxfs in the new policy.

Signed-off-by: Gary Tierney <gary.tierney@gmx.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: log errors when loading new policy

Adds error logging to the code paths which can fail when loading a new
policy in sel_write_load(). If the policy fails to be loaded from
userspace then a warning message is printed, whereas if a failure occurs
after loading policy from userspace an error message will be printed
with details on where policy loading failed (recreating one of /classes/,
/policy_capabilities/, /booleans/ in the SELinux fs).

Also, if sel_make_bools() fails to obtain an SID for an entry in
/booleans/* an error will be printed indicating the path of the
boolean.

Signed-off-by: Gary Tierney <gary.tierney@gmx.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: clean up cred usage and simplify

SELinux was sometimes using the task "objective" credentials when
it could/should use the "subjective" credentials. This was sometimes
hidden by the fact that we were unnecessarily passing around pointers
to the current task, making it appear as if the task could be something
other than current, so eliminate all such passing of current. Inline
various permission checking helper functions that can be reduced to a
single avc_has_perm() call.

Since the credentials infrastructure only allows a task to alter
its own credentials, we can always assume that current must be the same
as the target task in selinux_setprocattr after the check. We likely
should move this check from selinux_setprocattr() to proc_pid_attr_write()
and drop the task argument to the security hook altogether; it can only
serve to confuse things.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: support distinctions among all network address families

Extend SELinux to support distinctions among all network address families
implemented by the kernel by defining new socket security classes
and mapping to them. Otherwise, many sockets are mapped to the generic
socket class and are indistinguishable in policy. This has come up
previously with regard to selectively allowing access to bluetooth sockets,
and more recently with regard to selectively allowing access to AF_ALG
sockets. Guido Trentalancia submitted a patch that took a similar approach
to add only support for distinguishing AF_ALG sockets, but this generalizes
his approach to handle all address families implemented by the kernel.
Socket security classes are also added for ICMP and SCTP sockets.
Socket security classes were not defined for AF_* values that are reserved
but unimplemented in the kernel, e.g. AF_NETBEUI, AF_SECURITY, AF_ASH,
AF_ECONET, AF_SNA, AF_WANPIPE.

Backward compatibility is provided by only enabling the finer-grained
socket classes if a new policy capability is set in the policy; older
policies will behave as before. The legacy redhat1 policy capability
that was only ever used in testing within Fedora for ptrace_child
is reclaimed for this purpose; as far as I can tell, this policy
capability is not enabled in any supported distro policy.

Add a pair of conditional compilation guards to detect when new AF_* values
are added so that we can update SELinux accordingly rather than having to
belatedly update it long after new address families are introduced.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: normalize input to /sys/fs/selinux/enforce

At present, one can write any signed integer value to
/sys/fs/selinux/enforce and it will be stored,
e.g. echo -1 > /sys/fs/selinux/enforce or echo 2 >
/sys/fs/selinux/enforce. This makes no real difference
to the kernel, since it only ever cares if it is zero or non-zero,
but some userspace code compares it with 1 to decide if SELinux
is enforcing, and this could confuse it. Only a process that is
already root and is allowed the setenforce permission in SELinux
policy can write to /sys/fs/selinux/enforce, so this is not considered
to be a security issue, but it should be fixed.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>

selinux: Minor cleanups

Fix the comment for function __inode_security_revalidate, which returns
an integer.

Use the LABEL_* constants consistently for isec->initialized.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

fs: Replace CURRENT_TIME with current_time() for inode timestamps

CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_time() instead.

CURRENT_TIME is also not y2038 safe.

This is also in preparation for the patch that transitions
vfs timestamps to use 64 bit time and hence make them
y2038 safe. As part of the effort current_time() will be
extended to do range checks. Hence, it is necessary for all
file system timestamps to use current_time(). Also,
current_time() will be transitioned along with vfs to be
y2038 safe.

Note that whenever a single call to current_time() is used
to change timestamps in different inodes, it is because they
share the same time granularity.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Felipe Balbi <balbi@kernel.org>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

selinux: fix type mismatch

avc_cache_threshold is of type unsigned int. Do not use a signed
new_value in sscanf(page, "%u", &new_value).

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
[PM: subject prefix fix, description cleanup]
Signed-off-by: Paul Moore <paul@paul-moore.com>

wrappers for ->i_mutex access

parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

selinuxfs: switch to memdup_user_nul()

Nothing in there gives a damn about the buffer alignment - it
just parses its contents. So the use of get_zeroed_page()
doesn't buy us anything - might as well had been kmalloc(),
which makes that code equivalent to open-coded memdup_user_nul()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

selinux: export validatetrans decisions

Make validatetrans decisions available through selinuxfs.
"/validatetrans" is added to selinuxfs for this purpose.
This functionality is needed by file system servers
implemented in userspace or kernelspace without the VFS
layer.

Writing "$oldcontext $newcontext $tclass $taskcontext"
to /validatetrans is expected to return 0 if the transition
is allowed and -EPERM otherwise.

Signed-off-by: Andrew Perepechko <anserper@ya.ru>
CC: andrew.perepechko@seagate.com
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>

selinux: introduce security_context_str_to_sid

There seems to be a little confusion as to whether the scontext_len
parameter of security_context_to_sid() includes the nul-byte or
not. Reading security_context_to_sid_core(), it seems that the
expectation is that it does not (both the string copying and the test
for scontext_len being zero hint at that).

Introduce the helper security_context_str_to_sid() to do the strlen()
call and fix all callers.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>

mm: mark most vm_operations_struct const

With two exceptions (drm/qxl and drm/radeon) all vm_operations_struct
structs should be constant.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sysfs: Create mountpoints with sysfs_create_mount_point

This allows for better documentation in the code and
it allows for a simpler and fully correct version of
fs_fully_visible to be written.

The mount points converted and their filesystems are:
/sys/hypervisor/s390/ s390_hypfs
/sys/kernel/config/ configfs
/sys/kernel/debug/ debugfs
/sys/firmware/efi/efivars/ efivarfs
/sys/fs/fuse/connections/ fusectl
/sys/fs/pstore/ pstore
/sys/kernel/tracing/ tracefs
/sys/fs/cgroup/ cgroup
/sys/kernel/security/ securityfs
/sys/fs/selinux/ selinuxfs
/sys/fs/smackfs/ smackfs

Cc: stable@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

VFS: security/: d_inode() annotations

... except where that code acts as a filesystem driver, rather than
working with dentries given to it.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

selinux: fix sel_write_enforce broken return value

Return a negative error value like the rest of the entries in this function.

Cc: <stable@vger.kernel.org>
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: tweaked subject line]
Signed-off-by: Paul Moore <pmoore@redhat.com>

selinuxfs: don't open-code d_genocide()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

move d_rcu from overlapping d_child to overlapping d_alias

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

selinux: add gfp argument to security_xfrm_policy_alloc and fix callers

security_xfrm_policy_alloc can be called in atomic context so the
allocation should be done with GFP_ATOMIC. Add an argument to let the
callers choose the appropriate way. In order to do so a gfp argument
needs to be added to the method xfrm_policy_alloc_security in struct
security_operations and to the internal function
selinux_xfrm_alloc_user. After that switch to GFP_ATOMIC in the atomic
callers and leave GFP_KERNEL as before for the rest.
The path that needed the gfp argument addition is:
security_xfrm_policy_alloc -> security_ops.xfrm_policy_alloc_security ->
all users of xfrm_policy_alloc_security (e.g. selinux_xfrm_policy_alloc) ->
selinux_xfrm_alloc_user (here the allocation used to be GFP_KERNEL only)

Now adding a gfp argument to selinux_xfrm_alloc_user requires us to also
add it to security_context_to_sid which is used inside and prior to this
patch did only GFP_KERNEL allocation. So add gfp argument to
security_context_to_sid and adjust all of its callers as well.

CC: Paul Moore <paul@paul-moore.com>
CC: Dave Jones <davej@redhat.com>
CC: Steffen Klassert <steffen.klassert@secunet.com>
CC: Fan Du <fan.du@windriver.com>
CC: David S. Miller <davem@davemloft.net>
CC: LSM list <linux-security-module@vger.kernel.org>
CC: SELinux list <selinux@tycho.nsa.gov>

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

security: replace strict_strto*() with kstrto*()

The usage of strict_strto*() is not preferred, because
strict_strto*() is obsolete. Thus, kstrto*() should be
used.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

Add SELinux policy capability for always checking packet and peer classes.

Currently the packet class in SELinux is not checked if there are no
SECMARK rules in the security or mangle netfilter tables. Some systems
prefer that packets are always checked, for example, to protect the system
should the netfilter rules fail to load or if the nefilter rules
were maliciously flushed.

Add the always_check_network policy capability which, when enabled, treats
SECMARK as enabled, even if there are no netfilter SECMARK rules and
treats peer labeling as enabled, even if there is no Netlabel or
labeled IPSEC configuration.

Includes definition of "redhat1" SELinux policy capability, which
exists in the SELinux userpace library, to keep ordering correct.

The SELinux userpace portion of this was merged last year, but this kernel
change fell on the floor.

Signed-off-by: Chris PeBenito <cpebenito@tresys.com>
Signed-off-by: Eric Paris <eparis@redhat.com>

new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

mm: kill vma flag VM_RESERVED and mm->reserved_vm counter

A long time ago, in v2.4, VM_RESERVED kept swapout process off VMA,
currently it lost original meaning but still has some effects:

| effect | alternative flags
-+------------------------+---------------------------------------------
1| account as reserved_vm | VM_IO
2| skip in core dump | VM_IO, VM_DONTDUMP
3| do not merge or expand | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP
4| do not mlock | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP

This patch removes reserved_vm counter from mm_struct. Seems like nobody
cares about it, it does not exported into userspace directly, it only
reduces total_vm showed in proc.

Thus VM_RESERVED can be replaced with VM_IO or pair VM_DONTEXPAND | VM_DONTDUMP.

remap_pfn_range() and io_remap_pfn_range() set VM_IO|VM_DONTEXPAND|VM_DONTDUMP.
remap_vmalloc_range() set VM_DONTEXPAND | VM_DONTDUMP.

[akpm@linux-foundation.org: drivers/vfio/pci/vfio_pci.c fixup]
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

userns: Convert selinux to use kuid and kgid where appropriate

Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

switch dentry_open() to struct path, make it grab references itself

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

selinuxfs snprintf() misuses

a) %d does _not_ produce a page worth of output
b) snprintf() doesn't return negatives - it used to in old glibc, but
that's the kernel...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

SELinux: if sel_make_bools errors don't leave inconsistent state

We reset the bool names and values array to NULL, but do not reset the
number of entries in these arrays to 0. If we error out and then get back
into this function we will walk these NULL pointers based on the belief
that they are non-zero length.

Signed-off-by: Eric Paris <eparis@redhat.com>
cc: stable@kernel.org

SELinux: remove needless sel_div function

I'm not really sure what the idea behind the sel_div function is, but it's
useless. Since a and b are both unsigned, it's impossible for a % b < 0.
That means that part of the function never does anything. Thus it's just a
normal /. Just do that instead. I don't even understand what that operation
was supposed to mean in the signed case however....

If it was signed:
sel_div(-2, 4) == ((-2 / 4) - ((-2 % 4) < 0))
((0) - ((-2) < 0))
((0) - (1))
(-1)

What actually happens:
sel_div(-2, 4) == ((18446744073709551614 / 4) - ((18446744073709551614 % 4) < 0))
((4611686018427387903) - ((2 < 0))
(4611686018427387903 - 0)
((unsigned int)4611686018427387903)
(4294967295)

Neither makes a whole ton of sense to me. So I'm getting rid of the
function entirely.

Signed-off-by: Eric Paris <eparis@redhat.com>

SELinux: loosen DAC perms on reading policy

There is no reason the DAC perms on reading the policy file need to be root
only. There are selinux checks which should control this access.

Signed-off-by: Eric Paris <eparis@redhat.com>

SELinux: allow seek operations on the file exposing policy

sesearch uses:
lseek(3, 0, SEEK_SET) = -1 ESPIPE (Illegal seek)

Make that work.

Signed-off-by: Eric Paris <eparis@redhat.com>

selinuxfs: merge dentry allocation into sel_make_dir()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

selinux: sparse fix: fix warnings in netlink code

Fix sparse warnings in SELinux Netlink code.

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Eric Paris <eparis@redhat.com>

selinux: sparse fix: eliminate warnings for selinuxfs

Fixes several sparse warnings for selinuxfs.c

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Eric Paris <eparis@redhat.com>

selinux: sparse fix: declare selinux_disable() in security.h

Sparse fix: declare selinux_disable() in security.h

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Eric Paris <eparis@redhat.com>

selinuxfs: remove custom hex_to_bin()

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Eric Paris <eparis@parisplace.org>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: sparse fix: fix warnings in netlink code

Fix sparse warnings in SELinux Netlink code.

Signed-off-by: James Morris <jmorris@namei.org>

selinux: sparse fix: eliminate warnings for selinuxfs

Fixes several sparse warnings for selinuxfs.c

Signed-off-by: James Morris <jmorris@namei.org>

selinux: sparse fix: declare selinux_disable() in security.h

Sparse fix: declare selinux_disable() in security.h

Signed-off-by: James Morris <jmorris@namei.org>

doc: Update the email address for Paul Moore in various source files

My @hp.com will no longer be valid starting August 5, 2011 so an update is
necessary. My new email address is employer independent so we don't have
to worry about doing this again any time soon.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: James Morris <jmorris@namei.org>

doc: Update the email address for Paul Moore in various source files

My @hp.com will no longer be valid starting August 5, 2011 so an update is
necessary. My new email address is employer independent so we don't have
to worry about doing this again any time soon.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VFS : mount lock scalability for internal mounts

For a number of file systems that don't have a mount point (e.g. sockfs
and pipefs), they are not marked as long term. Therefore in
mntput_no_expire, all locks in vfs_mount lock are taken instead of just
local cpu's lock to aggregate reference counts when we release
reference to file objects. In fact, only local lock need to have been
taken to update ref counts as these file systems are in no danger of
going away until we are ready to unregister them.

The attached patch marks file systems using kern_mount without
mount point as long term. The contentions of vfs_mount lock
is now eliminated. Before un-registering such file system,
kern_unmount should be called to remove the long term flag and
make the mount point ready to be freed.

Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

selinux: fix case of names with whitespace/multibytes on /selinux/create

I submit the patch again, according to patch submission convension.

This patch enables to accept percent-encoded object names as forth
argument of /selinux/create interface to avoid possible bugs when we
give an object name including whitespace or multibutes.

E.g) if and when a userspace object manager tries to create a new object
named as "resolve.conf but fake", it shall give this name as the forth
argument of the /selinux/create. But sscanf() logic in kernel space
fetches only the part earlier than the first whitespace.
In this case, selinux may unexpectedly answer a default security context
configured to "resolve.conf", but it is bug.

Although I could not test this patch on named TYPE_TRANSITION rules
actually, But debug printk() message seems to me the logic works
correctly.
I assume the libselinux provides an interface to apply this logic
transparently, so nothing shall not be changed from the viewpoint of
application.

Signed-off-by: KaiGai Kohei <kohei.kaigai@emea.nec.com>
Signed-off-by: Eric Paris <eparis@redhat.com>

selinux: avoid unnecessary avc cache stat hit count

There is no point in counting hits - we can calculate it from the number
of lookups and misses.

This makes the avc statistics a bit smaller, and makes the code
generation better too.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

SELINUX: add /sys/fs/selinux mount point to put selinuxfs

In the interest of keeping userspace from having to create new root
filesystems all the time, let's follow the lead of the other in-kernel
filesystems and provide a proper mount point for it in sysfs.

For selinuxfs, this mount point should be in /sys/fs/selinux/

Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Lennart Poettering <mzerqung@0pointer.de>
Cc: Daniel J Walsh <dwalsh@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
[include kobject.h - Eric Paris]
[use selinuxfs_obj throughout - Eric Paris]
Signed-off-by: Eric Paris <eparis@redhat.com>

treewide: remove extra semicolons

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

selinux: add type_transition with name extension support for selinuxfs

The attached patch allows /selinux/create takes optional 4th argument
to support TYPE_TRANSITION with name extension for userspace object
managers.
If 4th argument is not supplied, it shall perform as existing kernel.
In fact, the regression test of SE-PostgreSQL works well on the patched
kernel.

Thanks,

Signed-off-by: KaiGai Kohei <kohei.kaigai@eu.nec.com>
[manually verify fuzz was not an issue, and it wasn't: eparis]
Signed-off-by: Eric Paris <eparis@redhat.com>

fs: dcache rationalise dget variants

dget_locked was a shortcut to avoid the lazy lru manipulation when we already
held dcache_lock (lru manipulation was relatively cheap at that point).
However, how that the lru lock is an innermost one, we never hold it at any
caller, so the lock cost can now be avoided. We already have well working lazy
dcache LRU, so it should be fine to defer LRU manipulations to scan time.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>

fs: dcache remove dcache_lock

dcache_lock no longer protects anything. remove it.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>

fs: dcache scale subdirs

Protect d_subdirs and d_child with d_lock, except in filesystems that aren't
using dcache_lock for these anyway (eg. using i_mutex).

Note: if we change the locking rule in future so that ->d_child protection is
provided only with ->d_parent->d_lock, it may allow us to reduce some locking.
But it would be an exception to an otherwise regular locking scheme, so we'd
have to see some good results. Probably not worthwhile.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>

SELinux: do not set automatic i_ino in selinuxfs

selinuxfs carefully uses i_ino to figure out what the inode refers to. The
VFS used to generically set this value and we would reset it to something
useable. After 85fe4025c616 each filesystem sets this value to a default
if needed. Since selinuxfs doesn't use the default value and it can only
lead to problems (I'd rather have 2 inodes with i_ino == 0 than one
pointing to the wrong data) lets just stop setting a default.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: James Morris <jmorris@namei.org>

SELinux: standardize return code handling in selinuxfs.c

selinuxfs.c has lots of different standards on how to handle return paths on
error. For the most part transition to

rc=errno
if (failure)
goto out;
[...]
out:
cleanup()
return rc;

Instead of doing cleanup mid function, or having multiple returns or other
options. This doesn't do that for every function, but most of the complex
functions which have cleanup routines on error.

Signed-off-by: Eric Paris <eparis@redhat.com>

convert get_sb_single() users

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs: do not assign default i_ino in new_inode

Instead of always assigning an increasing inode number in new_inode
move the call to assign it into those callers that actually need it.
For now callers that need it is estimated conservatively, that is
the call is added to all filesystems that do not assign an i_ino
by themselves. For a few more filesystems we can avoid assigning
any inode number given that they aren't user visible, and for others
it could be done lazily when an inode number is actually needed,
but that's left for later patches.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

selinux: implement mmap on /selinux/policy

/selinux/policy allows a user to copy the policy back out of the kernel.
This patch allows userspace to actually mmap that file and use it directly.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

SELinux: allow userspace to read policy back out of the kernel

There is interest in being able to see what the actual policy is that was
loaded into the kernel. The patch creates a new selinuxfs file
/selinux/policy which can be read by userspace. The actual policy that is
loaded into the kernel will be written back out to userspace.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: fast status update interface (/selinux/status)

This patch provides a new /selinux/status entry which allows applications
read-only mmap(2).
This region reflects selinux_kernel_status structure in kernel space.
struct selinux_kernel_status
{
u32 length; /* length of this structure */
u32 sequence; /* sequence number of seqlock logic */
u32 enforcing; /* current setting of enforcing mode */
u32 policyload; /* times of policy reloaded */
u32 deny_unknown; /* current setting of deny_unknown */
};

When userspace object manager caches access control decisions provided
by SELinux, it needs to invalidate the cache on policy reload and setenforce
to keep consistency.
However, the applications need to check the kernel state for each accesses
on userspace avc, or launch a background worker process.
In heuristic, frequency of invalidation is much less than frequency of
making access control decision, so it is annoying to invoke a system call
to check we don't need to invalidate the userspace cache.
If we can use a background worker thread, it allows to receive invalidation
messages from the kernel. But it requires us an invasive coding toward the
base application in some cases; E.g, when we provide a feature performing
with SELinux as a plugin module, it is unwelcome manner to launch its own
worker thread from the module.

If we could map /selinux/status to process memory space, application can
know updates of selinux status; policy reload or setenforce.

A typical application checks selinux_kernel_status::sequence when it tries
to reference userspace avc. If it was changed from the last time when it
checked userspace avc, it means something was updated in the kernel space.
Then, the application can reset userspace avc or update current enforcing
mode, without any system call invocations.
This sequence number is updated according to the seqlock logic, so we need
to wait for a while if it is odd number.

Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by: Eric Paris <eparis@redhat.com>
--
security/selinux/include/security.h | 21 ++++++
security/selinux/selinuxfs.c | 56 +++++++++++++++
security/selinux/ss/Makefile | 2 +-
security/selinux/ss/services.c | 3 +
security/selinux/ss/status.c | 129 +++++++++++++++++++++++++++++++++++
5 files changed, 210 insertions(+), 1 deletions(-)
Signed-off-by: James Morris <jmorris@namei.org>

selinux: use generic_file_llseek

The default for llseek will change to no_llseek,
so selinuxfs needs to add explicit .llseek
assignments. Since we're dealing with regular
files from a VFS perspective, use generic_file_llseek.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: James Morris <jmorris@namei.org>

Security: Fix coding style in security/

Fix coding style in security/

Signed-off-by: Zhitong Wang <zhitong.wangzt@alibaba-inc.com>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: fix memory leak in sel_make_bools

In sel_make_bools, kernel allocates memory for bool_pending_names[i]
with security_get_bools. So if we just free bool_pending_names, those
memories for bool_pending_names[i] will be leaked.

This patch resolves dozens of following kmemleak report after resuming
from suspend:
unreferenced object 0xffff88022e4c7380 (size 32):
comm "init", pid 1, jiffies 4294677173
backtrace:
[<ffffffff810f76b5>] create_object+0x1a2/0x2a9
[<ffffffff810f78bb>] kmemleak_alloc+0x26/0x4b
[<ffffffff810ef3eb>] __kmalloc+0x18f/0x1b8
[<ffffffff811cd511>] security_get_bools+0xd7/0x16f
[<ffffffff811c48c0>] sel_write_load+0x12e/0x62b
[<ffffffff810f9a39>] vfs_write+0xae/0x10b
[<ffffffff810f9b56>] sys_write+0x4a/0x6e
[<ffffffff81011b82>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff

Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: allow MLS->non-MLS and vice versa upon policy reload

Allow runtime switching between different policy types (e.g. from a MLS/MCS
policy to a non-MLS/non-MCS policy or viceversa).

Signed-off-by: Guido Trentalancia <guido@trentalancia.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: change the handling of unknown classes

If allow_unknown==deny, SELinux treats an undefined kernel security
class as an error condition rather than as a typical permission denial
and thus does not allow permissions on undefined classes even when in
permissive mode. Change the SELinux logic so that this case is handled
as a typical permission denial, subject to the usual permissive mode and
permissive domain handling.

Also drop the 'requested' argument from security_compute_av() and
helpers as it is a legacy of the original security server interface and
is unused.

Changes:
- Handle permissive domains consistently by moving up the test for a
permissive domain.
- Make security_compute_av_user() consistent with security_compute_av();
the only difference now is that security_compute_av() performs mapping
between the kernel-private class and permission indices and the policy
values. In the userspace case, this mapping is handled by libselinux.
- Moved avd_init inside the policy lock.

Based in part on a patch by Paul Moore <paul.moore@hp.com>.

Reported-by: Andrew Worsley <amworsley@gmail.com>
Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: dynamic class/perm discovery

Modify SELinux to dynamically discover class and permission values
upon policy load, based on the dynamic object class/perm discovery
logic from libselinux. A mapping is created between kernel-private
class and permission indices used outside the security server and the
policy values used within the security server.

The mappings are only applied upon kernel-internal computations;
similar mappings for the private indices of userspace object managers
is handled on a per-object manager basis by the userspace AVC. The
interfaces for compute_av and transition_sid are split for kernel
vs. userspace; the userspace functions are distinguished by a _user
suffix.

The kernel-private class indices are no longer tied to the policy
values and thus do not need to skip indices for userspace classes;
thus the kernel class index values are compressed. The flask.h
definitions were regenerated by deleting the userspace classes from
refpolicy's definitions and then regenerating the headers. Going
forward, we can just maintain the flask.h, av_permissions.h, and
classmap.h definitions separately from policy as they are no longer
tied to the policy values. The next patch introduces a utility to
automate generation of flask.h and av_permissions.h from the
classmap.h definitions.

The older kernel class and permission string tables are removed and
replaced by a single security class mapping table that is walked at
policy load to generate the mapping. The old kernel class validation
logic is completely replaced by the mapping logic.

The handle unknown logic is reworked. reject_unknown=1 is handled
when the mappings are computed at policy load time, similar to the old
handling by the class validation logic. allow_unknown=1 is handled
when computing and mapping decisions - if the permission was not able
to be mapped (i.e. undefined, mapped to zero), then it is
automatically added to the allowed vector. If the class was not able
to be mapped (i.e. undefined, mapped to zero), then all permissions
are allowed for it if allow_unknown=1.

avc_audit leverages the new security class mapping table to lookup the
class and permission names from the kernel-private indices.

The mdp program is updated to use the new table when generating the
class definitions and allow rules for a minimal boot policy for the
kernel. It should be noted that this policy will not include any
userspace classes, nor will its policy index values for the kernel
classes correspond with the ones in refpolicy (they will instead match
the kernel-private indices).

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: remove obsolete read buffer limit from sel_read_bool

On Tue, 2009-05-19 at 00:05 -0400, Eamon Walsh wrote:
> Recent versions of coreutils have bumped the read buffer size from 4K to
> 32K in several of the utilities.
>
> This means that "cat /selinux/booleans/xserver_object_manager" no longer
> works, it returns "Invalid argument" on F11. getsebool works fine.
>
> sel_read_bool has a check for "count > PAGE_SIZE" that doesn't seem to
> be present in the other read functions. Maybe it could be removed?

Yes, that check is obsoleted by the conversion of those functions to
using simple_read_from_buffer(), which will reduce count if necessary to
what is available in the buffer.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

Permissive domain in userspace object manager

This patch enables applications to handle permissive domain correctly.

Since the v2.6.26 kernel, SELinux has supported an idea of permissive
domain which allows certain processes to work as if permissive mode,
even if the global setting is enforcing mode.
However, we don't have an application program interface to inform
what domains are permissive one, and what domains are not.
It means applications focuses on SELinux (XACE/SELinux, SE-PostgreSQL
and so on) cannot handle permissive domain correctly.

This patch add the sixth field (flags) on the reply of the /selinux/access
interface which is used to make an access control decision from userspace.
If the first bit of the flags field is positive, it means the required
access control decision is on permissive domain, so application should
allow any required actions, as the kernel doing.

This patch also has a side benefit. The av_decision.flags is set at
context_struct_compute_av(). It enables to check required permissions
without read_lock(&policy_rwlock).

Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@redhat.com>
--
security/selinux/avc.c | 2 +-
security/selinux/include/security.h | 4 +++-
security/selinux/selinuxfs.c | 4 ++--
security/selinux/ss/services.c | 30 +++++-------------------------
4 files changed, 11 insertions(+), 29 deletions(-)
Signed-off-by: James Morris <jmorris@namei.org>

selinux: Remove the "compat_net" compatibility code

The SELinux "compat_net" is marked as deprecated, the time has come to
finally remove it from the kernel. Further code simplifications are
likely in the future, but this patch was intended to be a simple,
straight-up removal of the compat_net code.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>

SELinux: remove unused av.decided field

It appears there was an intention to have the security server only decide
certain permissions and leave other for later as some sort of a portential
performance win. We are currently always deciding all 32 bits of
permissions and this is a useless couple of branches and wasted space.
This patch completely drops the av.decided concept.

This in a 17% reduction in the time spent in avc_has_perm_noaudit
based on oprofile sampling of a tbench benchmark.

Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

zero i_uid/i_gid on inode allocation

... and don't bother in callers. Don't bother with zeroing i_blocks,
while we are at it - it's already been zeroed.

i_mode is not worth the effort; it has no common default value.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits.: core

Impact: cleanup

In future, all cpumask ops will only be valid (in general) for bit
numbers < nr_cpu_ids. So use that instead of NR_CPUS in iterators
and other comparisons.

This is always safe: no cpu number can be >= nr_cpu_ids, and
nr_cpu_ids is initialized to NR_CPUS at boot.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: James Morris <jmorris@namei.org>
Cc: Eric Biederman <ebiederm@xmission.com>

selinux: Deprecate and schedule the removal of the the compat_net functionality

This patch is the first step towards removing the old "compat_net" code from
the kernel. Secmark, the "compat_net" replacement was first introduced in
2.6.18 (September 2006) and the major Linux distributions with SELinux support
have transitioned to Secmark so it is time to start deprecating the "compat_net"
mechanism. Testing a patched version of 2.6.28-rc6 with the initial release of
Fedora Core 5 did not show any problems when running in enforcing mode.

This patch adds an entry to the feature-removal-schedule.txt file and removes
the SECURITY_SELINUX_ENABLE_SECMARK_DEFAULT configuration option, forcing
Secmark on by default although it can still be disabled at runtime. The patch
also makes the Secmark permission checks "dynamic" in the sense that they are
only executed when Secmark is configured; this should help prevent problems
with older distributions that have not yet migrated to Secmark.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>

CRED: Use RCU to access another task's creds and to release a task's own creds

Use RCU to access another task's creds and to release a task's own creds.
This means that it will be possible for the credentials of a task to be
replaced without another task (a) requiring a full lock to read them, and (b)
seeing deallocated memory.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>

CRED: Separate task security context from task_struct

Separate the task security context from task_struct. At this point, the
security data is temporarily embedded in the task_struct with two pointers
pointing to it.

Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in
entry.S via asm-offsets.

With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>

SELinux: more user friendly unknown handling printk

I've gotten complaints and reports about people not understanding the
meaning of the current unknown class/perm handling the kernel emits on
every policy load. Hopefully this will make make it clear to everyone
the meaning of the message and won't waste a printk the user won't care
about anyway on systems where the kernel and the policy agree on
everything.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

SELinux: keep the code clean formating and syntax

Formatting and syntax changes

whitespace, tabs to spaces, trailing space
put open { on same line as struct def
remove unneeded {} after if statements
change printk("Lu") to printk("llu")
convert asm/uaccess.h to linux/uaacess.h includes
remove unnecessary asm/bug.h includes
convert all users of simple_strtol to strict_strtol

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

SELinux: cleanup on isle selinuxfs.c

Why would anyone just clean up white space all day? Because they were
out too late last night and don't want to think for a day. So here is a
nice clean selinuxfs.c patch.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

SELinux: clean up printks

Make sure all printk start with KERN_*
Make sure all printk end with \n
Make sure all printk have the word 'selinux' in them
Change "function name" to "%s", __func__ (found 2 wrong)

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

security: Remove unnecessary inclusions of asm/semaphore.h

None of these files use any of the functionality promised by
asm/semaphore.h.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>

security: replace remaining __FUNCTION__ occurrences

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: James Morris <jmorris@namei.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Morris <jmorris@namei.org>

SELinux: create new open permission

Adds a new open permission inside SELinux when 'opening' a file. The idea
is that opening a file and reading/writing to that file are not the same
thing. Its different if a program had its stdout redirected to /tmp/output
than if the program tried to directly open /tmp/output. This should allow
policy writers to more liberally give read/write permissions across the
policy while still blocking many design and programing flaws SELinux is so
good at catching today.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>

[AUDIT] add session id to audit messages

In order to correlate audit records to an individual login add a session
id. This is incremented every time a user logs in and is included in
almost all messages which currently output the auid. The field is
labeled ses= or oses=

Signed-off-by: Eric Paris <eparis@redhat.com>

[PATCH] switch audit_get_loginuid() to task_struct *

all callers pass something->audit_context

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

SELinux: Add a capabilities bitmap to SELinux policy version 22

Add a new policy capabilities bitmap to SELinux policy version 22. This bitmap
will enable the security server to query the policy to determine which features
it supports.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>

security/selinux: constify function pointer tables and fields

Constify function pointer tables and fields.

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: James Morris <jmorris@namei.org>

SELinux: detect dead booleans

Instead of using f_op to detect dead booleans, check the inode index
against the number of booleans and check the dentry name against the
boolean name for that index on reads and writes. This prevents
incorrect use of a boolean file opened prior to a policy reload while
allowing valid use of it as long as it still corresponds to the same
boolean in the policy.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

SELinux: do not clear f_op when removing entries

Do not clear f_op when removing entries since it isn't safe to do.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

SELinux: policy selectable handling of unknown classes and perms

Allow policy to select, in much the same way as it selects MLS support, how
the kernel should handle access decisions which contain either unknown
classes or unknown permissions in known classes. The three choices for the
policy flags are

0 - Deny unknown security access. (default)
2 - reject loading policy if it does not contain all definitions
4 - allow unknown security access

The policy's choice is exported through 2 booleans in
selinuxfs. /selinux/deny_unknown and /selinux/reject_unknown.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: add selinuxfs structure for object class discovery

The structure is as follows (relative to selinuxfs root):

/class/file/index
/class/file/perms/read
/class/file/perms/write
...

Each class is allocated 33 inodes, 1 for the class index and 32 for
permissions. Relative to SEL_CLASS_INO_OFFSET, the inode of the index file
DIV 33 is the class number. The inode of the permission file % 33 is the
index of the permission for that class.

Signed-off-by: Christopher J. PeBenito <cpebenito@tresys.com>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: change sel_make_dir() to specify inode counter.

Specify the inode counter explicitly in sel_make_dir(), rather than always
using sel_last_ino.

Signed-off-by: Christopher J. PeBenito <cpebenito@tresys.com>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: rename sel_remove_bools() for more general usage.

sel_remove_bools() will also be used by the object class discovery, rename
it for more general use.

Signed-off-by: Christopher J. PeBenito <cpebenito@tresys.com>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: change numbering of boolean directory inodes in selinuxfs

Change the numbering of the booleans directory inodes in selinuxfs to
provide more room for new inodes without a conflict in inode numbers and
to be consistent with how inode numbering is done in the
initial_contexts directory.

Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@parisplace.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: remove unused enumeration constant from selinuxfs

Remove the unused enumeration constant, SEL_AVC, from the sel_inos
enumeration in selinuxfs.

Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@parisplace.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: explicitly number all selinuxfs inodes

Explicitly number all selinuxfs inodes to prevent a conflict between
inodes numbered using last_ino when created with new_inode() and those
labeled explicitly.

Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@parisplace.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

selinux: export initial SID contexts via selinuxfs

Make the initial SID contexts accessible to userspace via selinuxfs.
An initial use of this support will be to make the unlabeled context
available to libselinux for use for invalidated userspace SIDs.

Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

[PATCH] mark struct file_operations const 9

Many struct file_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[PATCH] struct path: convert selinux

Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] r/o bind mount prepwork: inc_nlink() helper

This is mostly included for parity with dec_nlink(), where we will have some
more hooks. This one should stay pretty darn straightforward for now.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] inode-diet: Eliminate i_blksize from the inode structure

This eliminates the i_blksize field from struct inode. Filesystems that want
to provide a per-inode st_blksize can do so by providing their own getattr
routine instead of using the generic_fillattr() function.

Note that some filesystems were providing pretty much random (and incorrect)
values for i_blksize.

[bunk@stusta.de: cleanup]
[akpm@osdl.org: generic_fillattr() fix]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Remove obsolete #include <linux/config.h>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

[PATCH] VFS: Permit filesystem to override root dentry on mount

Extend the get_sb() filesystem operation to take an extra argument that
permits the VFS to pass in the target vfsmount that defines the mountpoint.

The filesystem is then required to manually set the superblock and root dentry
pointers. For most filesystems, this should be done with simple_set_mnt()
which will set the superblock pointer and then set the root dentry to the
superblock's s_root (as per the old default behaviour).

The get_sb() op now returns an integer as there's now no need to return the
superblock pointer.

This patch permits a superblock to be implicitly shared amongst several mount
points, such as can be done with NFS to avoid potential inode aliasing. In
such a case, simple_set_mnt() would not be called, and instead the mnt_root
and mnt_sb would be set directly.

The patch also makes the following changes:

(*) the get_sb_*() convenience functions in the core kernel now take a vfsmount
pointer argument and return an integer, so most filesystems have to change
very little.

(*) If one of the convenience function is not used, then get_sb() should
normally call simple_set_mnt() to instantiate the vfsmount. This will
always return 0, and so can be tail-called from get_sb().

(*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the
dcache upon superblock destruction rather than shrink_dcache_anon().

This is required because the superblock may now have multiple trees that
aren't actually bound to s_root, but that still need to be cleaned up. The
currently called functions assume that the whole tree is rooted at s_root,
and that anonymous dentries are not the roots of trees which results in
dentries being left unculled.

However, with the way NFS superblock sharing are currently set to be
implemented, these assumptions are violated: the root of the filesystem is
simply a dummy dentry and inode (the real inode for '/' may well be
inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries
with child trees.

[*] Anonymous until discovered from another tree.

(*) The documentation has been adjusted, including the additional bit of
changing ext2_* into foo_* in the documentation.

[akpm@osdl.org: convert ipath_fs, do other stuff]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[SECMARK]: Add new packet controls to SELinux

Add new per-packet access controls to SELinux, replacing the old
packet controls.

Packets are labeled with the iptables SECMARK and CONNSECMARK targets,
then security policy for the packets is enforced with these controls.

To allow for a smooth transition to the new controls, the old code is
still present, but not active by default. To restore previous
behavior, the old controls may be activated at runtime by writing a
'1' to /selinux/compat_net, and also via the kernel boot parameter
selinux_compat_net. Switching between the network control models
requires the security load_policy permission. The old controls will
probably eventually be removed and any continued use is discouraged.

With this patch, the new secmark controls for SElinux are disabled by
default, so existing behavior is entirely preserved, and the user is
not affected at all.

It also provides a config option to enable the secmark controls by
default (which can always be overridden at boot and runtime). It is
also noted in the kconfig help that the user will need updated
userspace if enabling secmark controls for SELinux and that they'll
probably need the SECMARK and CONNMARK targets, and conntrack protocol
helpers, although such decisions are beyond the scope of kernel
configuration.

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

[PATCH] SELinux: fix hard link count for selinuxfs root directory

A further fix is needed for selinuxfs link count management, to ensure that
the count is correct for the parent directory when a subdirectory is
created. This is only required for the root directory currently, but the
code has been updated for the general case.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] selinuxfs cleanups: sel_make_avc_files

Fix copy & paste error in sel_make_avc_files(), removing a supurious call to
d_genocide() in the error path. All of this will be cleaned up by
kill_litter_super().

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] selinuxfs cleanups: sel_make_bools

Remove the call to sel_make_bools() from sel_fill_super(), as policy needs to
be loaded before the boolean files can be created. Policy will never be
loaded during sel_fill_super() as selinuxfs is kernel mounted during init and
the only means to load policy is via selinuxfs.

Also, the call to d_genocide() on the error path of sel_make_bools() is
incorrect and replaced with sel_remove_bools().

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] selinuxfs cleanups: sel_fill_super exit path

Unify the error path of sel_fill_super() so that all errors pass through the
same point and generate an error message. Also, removes a spurious dput() in
the error path which breaks the refcounting for the filesystem
(litter_kill_super() will correctly clean things up itself on error).

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] selinuxfs cleanups: use sel_make_dir()

Use existing sel_make_dir() helper to create booleans directory rather than
duplicating the logic.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] selinuxfs cleanups: fix hard link count

Fix the hard link count for selinuxfs directories, which are currently one
short.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] selinux: simplify sel_read_bool

Simplify sel_read_bool to use the simple_read_from_buffer helper, like the
other selinuxfs functions.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] sem2mutex: security/

Semaphore to mutex conversion.

The conversion was generated via scripts, and the result was validated
automatically via a script as well.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Stephen Smalley <sds@epoch.ncsc.mil>
Cc: James Morris <jmorris@namei.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] SE Linux audit events

Attached is a patch that hardwires important SE Linux events to the audit
system. Please Apply.

Signed-off-by: Steve Grubb <sgrubb@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

[PATCH] shrink dentry struct

Some long time ago, dentry struct was carefully tuned so that on 32 bits
UP, sizeof(struct dentry) was exactly 128, ie a power of 2, and a multiple
of memory cache lines.

Then RCU was added and dentry struct enlarged by two pointers, with nice
results for SMP, but not so good on UP, because breaking the above tuning
(128 + 8 = 136 bytes)

This patch reverts this unwanted side effect, by using an union (d_u),
where d_rcu and d_child are placed so that these two fields can share their
memory needs.

At the time d_free() is called (and d_rcu is really used), d_child is known
to be empty and not touched by the dentry freeing.

Lockless lookups only access d_name, d_parent, d_lock, d_op, d_flags (so
the previous content of d_child is not needed if said dentry was unhashed
but still accessed by a CPU because of RCU constraints)

As dentry cache easily contains millions of entries, a size reduction is
worth the extra complexity of the ugly C union.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Dipankar Sarma <dipankar@in.ibm.com>
Cc: Maneesh Soni <maneesh@in.ibm.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Ian Kent <raven@themaw.net>
Cc: Paul Jackson <pj@sgi.com>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: James Morris <jmorris@namei.org>
Cc: Stephen Smalley <sds@epoch.ncsc.mil>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] selinux: ARRAY_SIZE cleanups

Use ARRAY_SIZE macro instead of sizeof(x)/sizeof(x[0]).

Signed-off-by: Nicolas Kaiser <nikai@nikai.net>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] selinux: extend selinuxfs context interface

This patch extends the selinuxfs context interface to allow return the
canonical form of the context to userspace.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] reduce sizeof(struct file)

Now that RCU applied on 'struct file' seems stable, we can place f_rcuhead
in a memory location that is not anymore used at call_rcu(&f->f_rcuhead,
file_free_rcu) time, to reduce the size of this critical kernel object.

The trick I used is to move f_rcuhead and f_list in an union called f_u

The callers are changed so that f_rcuhead becomes f_u.fu_rcuhead and f_list
becomes f_u.f_list

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] SELinux: remove unecessary size_t checks in selinuxfs

This patch removes a bunch of unecessary checks for (size_t < 0) in
selinuxfs.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] SELinux: convert to kzalloc

This patch converts SELinux code from kmalloc/memset to the new kazalloc
unction. On i386, this results in a text saving of over 1K.

Before:
text data bss dec hex filename
86319 4642 15236 106197 19ed5 security/selinux/built-in.o

After:
text data bss dec hex filename
85278 4642 15236 105156 19ac4 security/selinux/built-in.o

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] SELinux: handle sel_make_bools() failure in selinuxfs

This patch fixes error handling in sel_make_bools(), where currently we'd
get a memory leak via security_get_bools() and try to kfree() the wrong
pointer if called again.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] selinux: kfree cleanup

kfree(NULL) is legal.

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!