Files are measured or appraised based on the IMA policy.  When a
file, in policy, is opened with the O_DIRECT flag, a deadlock
occurs.

The first attempt at resolving this lockdep temporarily removed the
O_DIRECT flag and restored it, after calculating the hash.  The
second attempt introduced the O_DIRECT_HAVELOCK flag. Based on this
flag, do_blockdev_direct_IO() would skip taking the i_mutex a second
time.  The third attempt, by Dmitry Kasatkin, resolves the i_mutex
locking issue, by re-introducing the IMA mutex, but uncovered
another problem.  Reading a file with O_DIRECT flag set, writes
directly to userspace pages.  A second patch allocates a user-space
like memory.  This works for all IMA hooks, except ima_file_free(),
which is called on __fput() to recalculate the file hash.

Until this last issue is addressed, do not 'collect' the
measurement for measuring, appraising, or auditing files opened
with the O_DIRECT flag set.  Based on policy, permit or deny file
access.  This patch defines a new IMA policy rule option named
'permit_directio'.  Policy rules could be defined, based on LSM
or other criteria, to permit specific applications to open files
with the O_DIRECT flag set.

Changelog v1:
- permit or deny file access based IMA policy rules
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Cc: <stable@vger.kernel.org>

After silencing the sleeping warning in mls_convert_context() I started
seeing similar traces from hashtab_insert. Do a cond_resched there too.
Signed-off-by: Dave Jones <davej@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>

On a slow machine (with debugging enabled), upgrading selinux policy may take
a considerable amount of time. Long enough that the softlockup detector
gets triggered.

The backtrace looks like this..

 > BUG: soft lockup - CPU#2 stuck for 23s! [load_policy:19045]
 > Call Trace:
 >  [<ffffffff81221ddf>] symcmp+0xf/0x20
 >  [<ffffffff81221c27>] hashtab_search+0x47/0x80
 >  [<ffffffff8122e96c>] mls_convert_context+0xdc/0x1c0
 >  [<ffffffff812294e8>] convert_context+0x378/0x460
 >  [<ffffffff81229170>] ? security_context_to_sid_core+0x240/0x240
 >  [<ffffffff812221b5>] sidtab_map+0x45/0x80
 >  [<ffffffff8122bb9f>] security_load_policy+0x3ff/0x580
 >  [<ffffffff810788a8>] ? sched_clock_cpu+0xa8/0x100
 >  [<ffffffff810786dd>] ? sched_clock_local+0x1d/0x80
 >  [<ffffffff810788a8>] ? sched_clock_cpu+0xa8/0x100
 >  [<ffffffff8103096a>] ? __change_page_attr_set_clr+0x82a/0xa50
 >  [<ffffffff810786dd>] ? sched_clock_local+0x1d/0x80
 >  [<ffffffff810788a8>] ? sched_clock_cpu+0xa8/0x100
 >  [<ffffffff8103096a>] ? __change_page_attr_set_clr+0x82a/0xa50
 >  [<ffffffff810788a8>] ? sched_clock_cpu+0xa8/0x100
 >  [<ffffffff81534ddc>] ? retint_restore_args+0xe/0xe
 >  [<ffffffff8109c82d>] ? trace_hardirqs_on_caller+0xfd/0x1c0
 >  [<ffffffff81279a2e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
 >  [<ffffffff810d28a8>] ? rcu_irq_exit+0x68/0xb0
 >  [<ffffffff81534ddc>] ? retint_restore_args+0xe/0xe
 >  [<ffffffff8121e947>] sel_write_load+0xa7/0x770
 >  [<ffffffff81139633>] ? vfs_write+0x1c3/0x200
 >  [<ffffffff81210e8e>] ? security_file_permission+0x1e/0xa0
 >  [<ffffffff8113952b>] vfs_write+0xbb/0x200
 >  [<ffffffff811581c7>] ? fget_light+0x397/0x4b0
 >  [<ffffffff81139c27>] SyS_write+0x47/0xa0
 >  [<ffffffff8153bde4>] tracesys+0xdd/0xe2

Stephen Smalley suggested:

 > Maybe put a cond_resched() within the ebitmap_for_each_positive_bit()
 > loop in mls_convert_context()?

That seems to do the trick. Tested by downgrading and re-upgrading selinux-policy-targeted.
Signed-off-by: Dave Jones <davej@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>

We presently prevent processes from using setexecon() to set the
security label of exec()'d processes when NO_NEW_PRIVS is enabled by
returning an error; however, we silently ignore setexeccon() when
exec()'ing from a nosuid mounted filesystem.  This patch makes things
a bit more consistent by returning an error in the setexeccon()/nosuid
case.
Signed-off-by: Paul Moore <pmoore@redhat.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>

We cannot presently tell from an avc: denied message whether access was in
fact denied or was allowed due to global or per-domain permissive mode.
Add a permissive= field to the avc message to reflect this information.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>

This fixes a warning about the mismatch of types between
the declared unsigned and integer.
Signed-off-by: Toralf Förster <toralf.foerster@gmx.de>

The cgroup filesystem isn't ready for an LSM to
properly use extented attributes. This patch makes
files created in the cgroup filesystem usable by
a system running Smack and systemd.

Targeted for git://git.gitorious.org/smack-next/kernel.gitSigned-off-by: Casey Schaufler <casey@schaufler-ca.com>

Smack believes that many of the operatons that can
be performed on an open file descriptor are read operations.
The fstat and lseek system calls are examples.
An implication of this is that files shouldn't be open
if the task doesn't have read access even if it has
write access and the file is being opened write only.

Targeted for git://git.gitorious.org/smack-next/kernel.gitSigned-off-by: Casey Schaufler <casey@schaufler-ca.com>

This typedef is unnecessary and should just be removed.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

Merge tag 'keys-20140314' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs into next

Smack IPC policy requires that the sender have write access
to the receiver. UDS streams don't do per-packet checks. The
only check is done at connect time. The existing code checks
if the connecting process can write to the other, but not the
other way around. This change adds a check that the other end
can write to the connecting process.

Targeted for git://git.gitorious.org/smack-next/kernel.gitSigned-off-by: Casey Schuafler <casey@schaufler-ca.com>

Sam Henderson points out that removing the SMACK64TRANSMUTE
attribute from a directory does not result in the directory
transmuting. This is because the inode flag indicating that
the directory is transmuting isn't cleared. The fix is a tad
less than trivial because smk_task and smk_mmap should have
been broken out, too.

Targeted for git://git.gitorious.org/smack-next/kernel.gitSigned-off-by: Casey Schaufler <casey@schaufler-ca.com>

The function `smack_inode_post_setxattr` is called each
time that a setxattr is done, for any value of name.
The kernel allow to put value==NULL when size==0
to set an empty attribute value. The systematic
call to smk_import_entry was causing the dereference
of a NULL pointer hence a KERNEL PANIC!

The problem can be produced easily by issuing the
command `setfattr -n user.data file` under bash prompt
when SMACK is active.

Moving the call to smk_import_entry as proposed by this
patch is correcting the behaviour because the function
smack_inode_post_setxattr is called for the SMACK's
attributes only if the function smack_inode_setxattr validated
the value and its size (what will not be the case when size==0).

It also has a benefical effect to not fill the smack hash
with garbage values coming from any extended attribute
write.

Change-Id: Iaf0039c2be9bccb6cee11c24a3b44d209101fe47
Signed-off-by: José Bollo <jose.bollo@open.eurogiciel.org>

1. In order to remove any SMACK extended attribute from a file, a user
should have CAP_MAC_ADMIN capability. But user without having this
capability is able to remove SMACK64MMAP security attribute.

2. While validating size and value of smack extended attribute in
smack_inode_setsecurity hook, wrong error code is returned.
Signed-off-by: Pankaj Kumar <pamkaj.k2@samsung.com>
Signed-off-by: Himanshu Shukla <himanshu.sh@samsung.com>

This allows to limit ptrace beyond the regular smack access rules.
It adds a smackfs/ptrace interface that allows smack to be configured
to require equal smack labels for PTRACE_MODE_ATTACH access.
See the changes in Documentation/security/Smack.txt below for details.
Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@partner.samsung.com>
Signed-off-by: Rafal Krypa <r.krypa@samsung.com>

The decision whether we can trace a process is made in the following
functions:
	smack_ptrace_traceme()
	smack_ptrace_access_check()
	smack_bprm_set_creds() (in case the proces is traced)

This patch unifies all those decisions by introducing one function that
checks whether ptrace is allowed: smk_ptrace_rule_check().

This makes possible to actually trace with TRACEME where first the
TRACEME itself must be allowed and then exec() on a traced process.

Additional bugs fixed:
- The decision is made according to the mode parameter that is now correctly
  translated from PTRACE_MODE_* to MAY_* instead of being treated 1:1.
  PTRACE_MODE_READ requires MAY_READ.
  PTRACE_MODE_ATTACH requires MAY_READWRITE.
- Add a smack audit log in case of exec() refused by bprm_set_creds().
- Honor the PTRACE_MODE_NOAUDIT flag and don't put smack audit info
  in case this flag is set.
Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@partner.samsung.com>
Signed-off-by: Rafal Krypa <r.krypa@samsung.com>

The order of subject/object is currently reversed in
smack_ptrace_traceme(). It is currently checked if the tracee has a
capability to trace tracer and according to this rule a decision is made
whether the tracer will be allowed to trace tracee.
Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@partner.samsung.com>
Signed-off-by: Rafal Krypa <r.krypa@samsung.com>

Fix a possible memory access fault when transmute is true and isp is NULL.
Signed-off-by: José Bollo <jose.bollo@open.eurogiciel.org>

Pull vfs fixes from Al Viro:
 "Switch mnt_hash to hlist, turning the races between __lookup_mnt() and
  hash modifications into false negatives from __lookup_mnt() (instead
  of hangs)"

On the false negatives from __lookup_mnt():
 "The *only* thing we care about is not getting stuck in __lookup_mnt().
  If it misses an entry because something in front of it just got moved
  around, etc, we are fine.  We'll notice that mount_lock mismatch and
  that'll be it"

* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  switch mnt_hash to hlist
  don't bother with propagate_mnt() unless the target is shared
  keep shadowed vfsmounts together
  resizable namespace.c hashes

I am the new kernel tree Documentation maintainer (except for parts that
are handled by other people, of course).
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull input updates from Dmitry Torokhov:
 "Some more updates for the input subsystem.

  You will get a fix for race in mousedev that has been causing quite a
  few oopses lately and a small fixup for force feedback support in
  evdev"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: mousedev - fix race when creating mixed device
  Input: don't modify the id of ioctl-provided ff effect on upload failure

It its possible to configure your PAM stack to refuse login if audit
messages (about the login) were unable to be sent.  This is common in
many distros and thus normal configuration of many containers.  The PAM
modules determine if audit is enabled/disabled in the kernel based on
the return value from sending an audit message on the netlink socket.
If userspace gets back ECONNREFUSED it believes audit is disabled in the
kernel.  If it gets any other error else it refuses to let the login
proceed.

Just about ever since the introduction of namespaces the kernel audit
subsystem has returned EPERM if the task sending a message was not in
the init user or pid namespace.  So many forms of containers have never
worked if audit was enabled in the kernel.

BUT if the container was not in net_init then the kernel network code
would send ECONNREFUSED (instead of the audit code sending EPERM).  Thus
by pure accident/dumb luck/bug if an admin configured the PAM stack to
reject all logins that didn't talk to audit, but then ran the login
untility in the non-init_net namespace, it would work!! Clearly this was
a bug, but it is a bug some people expected.

With the introduction of network namespace support in 3.14-rc1 the two
bugs stopped cancelling each other out.  Now, containers in the
non-init_net namespace refused to let users log in (just like PAM was
configfured!) Obviously some people were not happy that what used to let
users log in, now didn't!

This fix is kinda hacky.  We return ECONNREFUSED for all non-init
relevant namespaces.  That means that not only will the old broken
non-init_net setups continue to work, now the broken non-init_pid or
non-init_user setups will 'work'.  They don't really work, since audit
isn't logging things.  But it's what most users want.

In 3.15 we should have patches to support not only the non-init_net
(3.14) namespace but also the non-init_pid and non-init_user namespace.
So all will be right in the world.  This just opens the doors wide open
on 3.14 and hopefully makes users happy, if not the audit system...
Reported-by: Andre Tomt <andre@tomt.net>
Reported-by: Adam Richter <adam_richter2004@yahoo.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Use cmpxchg() to atomically set i_flags instead of clearing out the
S_IMMUTABLE, S_APPEND, etc. flags and then setting them from the
EXT4_IMMUTABLE_FL, EXT4_APPEND_FL flags, since this opens up a race
where an immutable file has the immutable flag cleared for a brief
window of time.
Reported-by: John Sullivan <jsrhbz@kanargh.force9.co.uk>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fixes RCU bug - walking through hlist is safe in face of element moves,
since it's self-terminating.  Cyclic lists are not - if we end up jumping
to another hash chain, we'll loop infinitely without ever hitting the
original list head.

[fix for dumb braino folded]

Spotted by: Max Kellermann <mk@cm4all.com>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

If the dest_mnt is not shared, propagate_mnt() does nothing -
there's no mounts to propagate to and thus no copies to create.
Might as well don't bother calling it in that case.

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

preparation to switching mnt_hash to hlist

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

* switch allocation to alloc_large_system_hash()
* make sizes overridable by boot parameters (mhash_entries=, mphash_entries=)
* switch mountpoint_hashtable from list_head to hlist_head

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

Pull timer fix from Ingo Molnar:
 "A late breaking fix from John.  (The bug fixed has a hard lockup
  potential, but that was not observed, warnings were)"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Revert to calling clock_was_set_delayed() while in irq context

Pull Ceph fix from Sage Weil:
 "This drops a bad assert that a few users have been hitting but we've
  only recently been able to track down"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  rbd: drop an unsafe assertion

We should not be using static variable mousedev_mix in methods that can be
called before that singleton gets assigned. While at it let's add open and
close methods to mousedev structure so that we do not need to test if we
are dealing with multiplexor or normal device and simply call appropriate
method directly.

This fixes: https://bugzilla.kernel.org/show_bug.cgi?id=71551Reported-by: GiulioDP <depasquale.giulio@gmail.com>
Tested-by: GiulioDP <depasquale.giulio@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

If a new (id == -1) ff effect was uploaded from userspace,
ff-core.c::input_ff_upload() will have assigned a positive number to the
new effect id.  Currently, evdev.c::evdev_do_ioctl() will save this new id
to userspace, regardless of whether the upload succeeded or not.

On upload failure, this can be confusing because the dev->ff->effects[]
array will not contain an element at the index of that new effect id.

This patch fixes this by leaving the id unchanged after upload fails.

Note: Unfortunately applications should still expect changed effect id for
quite some time.

This has been discussed on:
http://www.mail-archive.com/linux-input@vger.kernel.org/msg08513.html
("ff-core effect id handling in case of a failed effect upload")
Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Elias Vanderstuyft <elias.vds@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Olivier Bonvalet reported having repeated crashes due to a failed
assertion he was hitting in rbd_img_obj_callback():

    Assertion failure in rbd_img_obj_callback() at line 2165:
	rbd_assert(which >= img_request->next_completion);

With a lot of help from Olivier with reproducing the problem
we were able to determine the object and image requests had
already been completed (and often freed) at the point the
assertion failed.

There was a great deal of discussion on the ceph-devel mailing list
about this.  The problem only arose when there were two (or more)
object requests in an image request, and the problem was always
seen when the second request was being completed.

The problem is due to a race in the window between setting the
"done" flag on an object request and checking the image request's
next completion value.  When the first object request completes, it
checks to see if its successor request is marked "done", and if
so, that request is also completed.  In the process, the image
request's next_completion value is updated to reflect that both
the first and second requests are completed.  By the time the
second request is able to check the next_completion value, it
has been set to a value *greater* than its own "which" value,
which caused an assertion to fail.

Fix this problem by skipping over any completion processing
unless the completing object request is the next one expected.
Test only for inequality (not >=), and eliminate the bad
assertion.
Tested-by: Olivier Bonvalet <ob@daevel.fr>
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Sage Weil <sage@inktank.com>
Reviewed-by: Ilya Dryomov <ilya.dryomov@inktank.com>

Pull networking fixes from David Miller:

 1) We've discovered a common error in several networking drivers, they
    put VLAN offload features into ->vlan_features, which would suggest
    that they support offloading 2 or more levels of VLAN encapsulation.
    Not only do these devices not do that, but we don't have the
    infrastructure yet to handle that at all.

    Fixes from Vlad Yasevich.

 2) Fix tcpdump crash with bridging and vlans, also from Vlad.

 3) Some MAINTAINERS updates for random32 and bonding.

 4) Fix late reseeds of prandom generator, from Sasha Levin.

 5) Bridge doesn't handle stacked vlans properly, fix from Toshiaki
    Makita.

 6) Fix deadlock in openvswitch, from Flavio Leitner.

 7) get_timewait4_sock() doesn't report delay times correctly, fix from
    Eric Dumazet.

 8) Duplicate address detection and addrconf verification need to run in
    contexts where RTNL can be obtained.  Move them to run from a
    workqueue.  From Hannes Frederic Sowa.

 9) Fix route refcount leaking in ip tunnels, from Pravin B Shelar.

10) Don't return -EINTR from non-blocking recvmsg() on AF_UNIX sockets,
    from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (28 commits)
  vlan: Warn the user if lowerdev has bad vlan features.
  veth: Turn off vlan rx acceleration in vlan_features
  ifb: Remove vlan acceleration from vlan_features
  qlge: Do not propaged vlan tag offloads to vlans
  bridge: Fix crash with vlan filtering and tcpdump
  net: Account for all vlan headers in skb_mac_gso_segment
  MAINTAINERS: bonding: change email address
  MAINTAINERS: bonding: change email address
  ipv6: move DAD and addrconf_verify processing to workqueue
  tcp: fix get_timewait4_sock() delay computation on 64bit
  openvswitch: fix a possible deadlock and lockdep warning
  bridge: Fix handling stacked vlan tags
  bridge: Fix inabillity to retrieve vlan tags when tx offload is disabled
  vhost: validate vhost_get_vq_desc return value
  vhost: fix total length when packets are too short
  random32: avoid attempt to late reseed if in the middle of seeding
  random32: assign to network folks in MAINTAINERS
  net/mlx4_core: pass pci_device_id.driver_data to __mlx4_init_one during reset
  core, nfqueue, openvswitch: Orphan frags in skb_zerocopy and handle errors
  vlan: Set hard_header_len according to available acceleration
  ...

Vlad Yasevich says:

====================
Audit all drivers for correct vlan_features.

Some drivers set vlan acceleration features in vlan_features.  This causes
issues with Q-in-Q/802.1ad configurations.

Audit all the drivers for correct vlan_features.  Fix broken ones.
Add a warning to vlan code to help catch future offenders.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Some drivers incorrectly assign vlan acceleration features to
vlan_features thus causing issues for Q-in-Q vlan configurations.
Warn the user of such cases.
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

For completeness, turn off vlan rx acceleration in vlan_features so
that it doesn't show up on q-in-q setups.
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Do not include vlan acceleration features in vlan_features as that
precludes correct Q-in-Q operation.
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>