Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into next

integrity_kernel_read() duplicates the file read operations code
in vfs_read(). This patch refactors vfs_read() code creating a
helper function __vfs_read(). It is used by both vfs_read() and
integrity_kernel_read().
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

This patch provides CONFIG_IMA_APPRAISE_SIGNED_INIT kernel configuration
option to force IMA appraisal using signatures. This is useful, when EVM
key is not initialized yet and we want securely initialize integrity or
any other functionality.

It forces embedded policy to require signature. Signed initialization
script can initialize EVM key, update the IMA policy and change further
requirement of everything to be signed.

Changes in v3:
* kernel parameter fixed to configuration option in the patch description

Changes in v2:
* policy change of this patch separated from the key loading patch
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Keys can only be loaded once the rootfs is mounted. Initcalls
are not suitable for that. This patch defines a special hook
to load the x509 public keys onto the IMA keyring, before
attempting to access any file. The keys are required for
verifying the file's signature. The hook is called after the
root filesystem is mounted and before the kernel calls 'init'.

Changes in v3:
* added more explanation to the patch description (Mimi)

Changes in v2:
* Hook renamed as 'integrity_load_keys()' to handle both IMA and EVM
  keys by integrity subsystem.
* Hook patch moved after defining loading functions
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Define configuration option to load X509 certificate into the
IMA trusted kernel keyring. It implements ima_load_x509() hook
to load X509 certificate into the .ima trusted kernel keyring
from the root filesystem.

Changes in v3:
* use ima_policy_flag in ima_get_action()
  ima_load_x509 temporarily clears ima_policy_flag to disable
  appraisal to load key. Use it to skip appraisal rules.
* Key directory path changed to /etc/keys (Mimi)
* Expand IMA_LOAD_X509 Kconfig help

Changes in v2:
* added '__init'
* use ima_policy_flag to disable appraisal to load keys
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Provide the function to load x509 certificates from the kernel into the
integrity kernel keyring.

Changes in v2:
* configuration option removed
* function declared as '__init'
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

This patch defines a new function called integrity_read_file()
to read file from the kernel into a buffer. Subsequent patches
will read a file containing the public keys and load them onto
the IMA keyring.

This patch moves and renames ima_kernel_read(), the non-security
checking version of kernel_read(), to integrity_kernel_read().

Changes in v3:
* Patch descriptions improved (Mimi)
* Add missing cast (kbuild test robot)

Changes in v2:
* configuration option removed
* function declared as '__init'
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

This patch allows users to provide a custom template format through the
new kernel command line parameter 'ima_template_fmt'. If the supplied
format is not valid, IMA uses the default template descriptor.

Changelog:
 - v3:
   - added check for 'fields' and 'num_fields' in
     template_desc_init_fields() (suggested by Mimi Zohar)

 - v2:
   - using template_desc_init_fields() to validate a format string
     (Roberto Sassu)
   - updated documentation by stating that only the chosen template
     descriptor is initialized (Roberto Sassu)

 - v1:
   - simplified code of ima_template_fmt_setup()
     (Roberto Sassu, suggested by Mimi Zohar)
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

The allocation of a field pointers array is moved at the end of
template_desc_init_fields() and done only if the value of the 'fields'
and 'num_fields' parameters is not NULL. For just validating a template
format string, retrieved template field pointers are placed in a temporary
array.

Changelog:
 - v3:
   - do not check in this patch if 'fields' and 'num_fields' are NULL
     (suggested by Mimi Zohar)
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

This patch removes the allocation of a copy of 'template_fmt', needed for
iterating over all fields in the passed template format string. The removal
was possible by replacing strcspn(), which modifies the passed string,
with strchrnul(). The currently processed template field is copied in
a temporary variable.

The purpose of this change is use template_desc_init_fields() in two ways:
for just validating a template format string (the function should work
if called by a setup function, when memory cannot be allocated), and for
actually initializing a template descriptor. The implementation of this
feature will be complete with the next patch.

Changelog:
 - v3:
   - added 'goto out' in template_desc_init_fields() to free allocated
     memory if a template field length is not valid (suggested by
     Mimi Zohar)
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

With the introduction of the 'ima_template_fmt' kernel cmdline parameter,
a user can define a new template descriptor with custom format. However,
in this case, userspace tools will be unable to parse the measurements
list because the new template is unknown. For this reason, this patch
modifies the current IMA behavior to display in the list the template
format instead of the name (only if the length of the latter is zero)
so that a tool can extract needed information if it can handle listed
fields.

This patch also correctly displays the error log message in
ima_init_template() if the selected template cannot be initialized.

Changelog:
 - v3:
   - check the first byte of 'e->template_desc->name' instead of using
     strlen() in ima_fs.c (suggested by Mimi Zohar)

 - v2:
   - print the template format in ima_init_template(), if the selected
     template is custom (Roberto Sassu)

 - v1:
   - fixed patch description (Roberto Sassu, suggested by Mimi Zohar)
   - set 'template_name' variable in ima_fs.c only once
     (Roberto Sassu, suggested by Mimi Zohar)
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

This patch adds some error messages to inform users about the following
events: template descriptor not found, invalid template descriptor,
template field not found and template initialization failed.

Changelog:
 - v2:
   - display an error message if the format string contains too many
     fields (Roberto Sassu)
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

The current implementation uses an atomic counter to provide exclusive
access to the sysfs 'policy' entry to update the IMA policy. While it is
highly unlikely, the usage of a counter might potentially allow another
process to overflow the counter, open the interface and insert additional
rules into the policy being loaded.

This patch replaces using an atomic counter with atomic bit operations
which is more reliable and a widely used method to provide exclusive access.

As bit operation keep the interface locked after successful update, it makes
it unnecessary to verify if the default policy was set or not during parsing
and interface closing. This patch also removes that code.

Changes in v3:
* move audit log message to ima_relead_policy() to report successful and
  unsuccessful result
* unnecessary comment removed

Changes in v2:
* keep interface locked after successful policy load as in original design
* remove sysfs entry as in original design
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Empty policy lines cause parsing failures which is, especially
for new users, hard to spot. This patch prevents it.

Changes in v2:
* strip leading blanks and tabs in rules to prevent parsing failures
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

If a rule is a comment, there is no need to allocate an entry.
Move the checking for comments before allocating the entry.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Audit messages are rate limited, often causing the policy update
info to not be visible.  Report policy loading status also using
pr_info.

Changes in v2:
* reporting moved to ima_release_policy to notice parsing errors
* reporting both completed and failed status
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

__getname() uses slab allocation which is faster than kmalloc.
Make use of it.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

If filesystem is mounted read-only or file is immutable, updating
xattr will fail. This is a usual case during early boot until
filesystem is remount read-write. This patch verifies conditions
to skip unnecessary attempt to calculate HMAC and set xattr.

Changes in v2:
* indention changed according to Lindent (requested by Mimi)
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

integrity_init_keyring() is used only from kernel '__init'
functions. Add it there as well.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

This patch completes the switching to the 'ima_policy_flag' variable
in the checks at the beginning of IMA functions, starting with the
commit a756024e.

Checking 'iint_initialized' is completely unnecessary, because
S_IMA flag is unset if iint was not allocated. At the same time
the integrity cache is allocated with SLAB_PANIC and the kernel will
panic if the allocation fails during kernel initialization. So on
a running system iint_initialized is always true and can be removed.

Changes in v3:
* not limiting test to IMA_APPRAISE (spotted by Roberto Sassu)

Changes in v2:
* 'iint_initialized' removal patch merged to this patch (requested
   by Mimi)
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Acked-by: Roberto Sassu <roberto.sassu@polito.it>

Latest KEYS code return error if hexadecimal string length id odd.
Fix it.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>

Previous version of KEYS used to output last 4 bytes of fingerprint.
Now it outputs 8 last bytes of raw subject, which does not make any
visual meaning at all. This patch restores old behavior.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>

The 'id:' prefix must be stripped for asymmetric_key_hex_to_key_id() to be
able to process ca_keyid.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>

Earlier KEYS code used pure subject key identifiers (fingerprint)
for searching keys. Latest merged code removed that and broke
compatibility with integrity subsytem signatures and original
format of module signatures.

This patch returns back partial matching on SKID.
Reported-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>

Bring back the functionality whereby an asymmetric key can be matched with a
partial match on one of its IDs.

Whilst we're at it, allow for the possibility of having an increased number of
IDs.
Reported-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>

Pull SCSI fixes from James Bottomley:
 "This is a set of two small fixes, both to code which went in during
  the merge window: cxgb4i has a scheduling in atomic bug in its new
  ipv6 code and uas fails to work properly with the new scsi-mq code"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  [SCSI] uas: disable use of blk-mq I/O path
  [SCSI] cxgb4i: avoid holding mutex in interrupt context

Pull kconfig fixes for tiny setups from Josh Triplett:
 "Two Kconfig bugfixes for 3.17 related to tinification.  These fixes
  make the Kconfig "General Setup" menu much more usable"

* tag 'tiny/kconfig-for-3.17' of https://git.kernel.org/pub/scm/linux/kernel/git/josh/linux:
  init/Kconfig: Fix HAVE_FUTEX_CMPXCHG to not break up the EXPERT menu
  init/Kconfig: Hide printk log config if CONFIG_PRINTK=n

commit 03b8c7b6 ("futex: Allow
architectures to skip futex_atomic_cmpxchg_inatomic() test") added the
HAVE_FUTEX_CMPXCHG symbol right below FUTEX.  This placed it right in
the middle of the options for the EXPERT menu.  However,
HAVE_FUTEX_CMPXCHG does not depend on EXPERT or FUTEX, so Kconfig stops
placing items in the EXPERT menu, and displays the remaining several
EXPERT items (starting with EPOLL) directly in the General Setup menu.

Since both users of HAVE_FUTEX_CMPXCHG only select it "if FUTEX", make
HAVE_FUTEX_CMPXCHG itself depend on FUTEX.  With this change, the
subsequent items display as part of the EXPERT menu again; the EMBEDDED
menu now appears as the next top-level item in the General Setup menu,
which makes General Setup much shorter and more usable.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Cc: stable <stable@vger.kernel.org>

The buffers sized by CONFIG_LOG_BUF_SHIFT and
CONFIG_LOG_CPU_MAX_BUF_SHIFT do not exist if CONFIG_PRINTK=n, so don't
ask about their size at all.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Cc: stable <stable@vger.kernel.org>

Pull i2c fixes from Wolfram Sang:
 "Two i2c driver bugfixes"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: qup: Fix order of runtime pm initialization
  i2c: rk3x: fix 0 length write transfers

Merge tag 'trace-fixes-v3.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull trace ring buffer iterator fix from Steven Rostedt:
 "While testing some new changes for 3.18, I kept hitting a bug every so
  often in the ring buffer.  At first I thought it had to do with some
  of the changes I was working on, but then testing something else I
  realized that the bug was in 3.17 itself.  I ran several bisects as
  the bug was not very reproducible, and finally came up with the commit
  that I could reproduce easily within a few minutes, and without the
  change I could run the tests over an hour without issue.  The change
  fit the bug and I figured out a fix.  That bad commit was:

    Commit 651e22f2 "ring-buffer: Always reset iterator to reader page"

  This commit fixed a bug, but in the process created another one.  It
  used the wrong value as the cached value that is used to see if things
  changed while an iterator was in use.  This made it look like a change
  always happened, and could cause the iterator to go into an infinite
  loop"

* tag 'trace-fixes-v3.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ring-buffer: Fix infinite spin in reading buffer

Pull cifs/smb3 fixes from Steve French:
 "Fix for CIFS/SMB3 oops on reconnect during readpages (3.17 regression)
  and for incorrectly closing file handle in symlink error cases"

* 'for-linus' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Fix readpages retrying on reconnects
  Fix problem recognizing symlinks

Pull raid5 discard fix from Neil Brown:
 "One fix for raid5 discard issue"

* tag 'md/3.17-final-fix' of git://neil.brown.name/md:
  md/raid5: disable 'DISCARD' by default due to safety concerns.

Pull drm fixes from Dave Airlie:
 "Nothing too major or scary.

  One i915 regression fix, nouveau has a tmds regression fix, along with
  a regression fix for the runtime pm code for optimus laptops not
  restoring the display hw correctly"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/nouveau: make sure display hardware is reinitialised on runtime resume
  drm/nouveau: punt fbcon resume out to a workqueue
  drm/nouveau: fix regression on original nv50 board
  drm/nv50/disp: fix dpms regression on certain boards
  drm/i915: Flush the PTEs after updating them before suspend

Module signing matches keys by comparing against the key description exactly.
However, the way the key description gets constructed got changed to be
composed of the subject name plus the certificate serial number instead of the
subject name and the subjectKeyId.  I changed this to avoid problems with
certificates that don't *have* a subjectKeyId.

Instead, if available, use the raw subjectKeyId to form the key description
and only use the serial number if the subjectKeyId doesn't exist.
Reported-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>

If hexlen is odd then function returns an error.
Use IS_ERR to check for error, otherwise invalid pointer
is used and kernel gives oops:

[  132.816522] BUG: unable to handle kernel paging request at
ffffffffffffffea
[  132.819902] IP: [<ffffffff812bfc20>] asymmetric_key_id_same+0x14/0x36
[  132.820302] PGD 1a12067 PUD 1a14067 PMD 0
[  132.820302] Oops: 0000 [#1] SMP
[  132.820302] Modules linked in: bridge(E) stp(E) llc(E) evdev(E)
serio_raw(E) i2c_piix4(E) button(E) fuse(E)
[  132.820302] CPU: 0 PID: 2993 Comm: cat Tainted: G            E
3.16.0-kds+ #2847
[  132.820302] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  132.820302] task: ffff88004249a430 ti: ffff880056640000 task.ti:
ffff880056640000
[  132.820302] RIP: 0010:[<ffffffff812bfc20>]  [<ffffffff812bfc20>]
asymmetric_key_id_same+0x14/0x36
[  132.820302] RSP: 0018:ffff880056643930  EFLAGS: 00010246
[  132.820302] RAX: 0000000000000000 RBX: ffffffffffffffea RCX:
ffff880056643ae0
[  132.820302] RDX: 000000000000005e RSI: ffffffffffffffea RDI:
ffff88005bac9300
[  132.820302] RBP: ffff880056643948 R08: 0000000000000003 R09:
00000007504aa01a
[  132.820302] R10: 0000000000000000 R11: 0000000000000000 R12:
ffff88005d68ca40
[  132.820302] R13: 0000000000000101 R14: 0000000000000000 R15:
ffff88005bac5280
[  132.820302] FS:  00007f67a153c740(0000) GS:ffff88005da00000(0000)
knlGS:0000000000000000
[  132.820302] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  132.820302] CR2: ffffffffffffffea CR3: 000000002e663000 CR4:
00000000000006f0
[  132.820302] Stack:
[  132.820302]  ffffffff812bfc66 ffff880056643ae0 ffff88005bac5280
ffff880056643958
[  132.820302]  ffffffff812bfc9d ffff880056643980 ffffffff812971d9
ffff88005ce930c1
[  132.820302]  ffff88005ce930c0 0000000000000000 ffff8800566439c8
ffffffff812fb753
[  132.820302] Call Trace:
[  132.820302]  [<ffffffff812bfc66>] ? asymmetric_match_key_ids+0x24/0x42
[  132.820302]  [<ffffffff812bfc9d>] asymmetric_key_cmp+0x19/0x1b
[  132.820302]  [<ffffffff812971d9>] keyring_search_iterator+0x74/0xd7
[  132.820302]  [<ffffffff812fb753>] assoc_array_subtree_iterate+0x67/0xd2
[  132.820302]  [<ffffffff81297165>] ? key_default_cmp+0x20/0x20
[  132.820302]  [<ffffffff812fbaa1>] assoc_array_iterate+0x19/0x1e
[  132.820302]  [<ffffffff81297332>] search_nested_keyrings+0xf6/0x2b6
[  132.820302]  [<ffffffff810728da>] ? sched_clock_cpu+0x91/0xa2
[  132.820302]  [<ffffffff810860d2>] ? mark_held_locks+0x58/0x6e
[  132.820302]  [<ffffffff810a137d>] ? current_kernel_time+0x77/0xb8
[  132.820302]  [<ffffffff81297871>] keyring_search_aux+0xe1/0x14c
[  132.820302]  [<ffffffff812977fc>] ? keyring_search_aux+0x6c/0x14c
[  132.820302]  [<ffffffff8129796b>] keyring_search+0x8f/0xb6
[  132.820302]  [<ffffffff812bfc84>] ? asymmetric_match_key_ids+0x42/0x42
[  132.820302]  [<ffffffff81297165>] ? key_default_cmp+0x20/0x20
[  132.820302]  [<ffffffff812ab9e3>] asymmetric_verify+0xa4/0x214
[  132.820302]  [<ffffffff812ab90e>] integrity_digsig_verify+0xb1/0xe2
[  132.820302]  [<ffffffff812abe41>] ? evm_verifyxattr+0x6a/0x7a
[  132.820302]  [<ffffffff812b0390>] ima_appraise_measurement+0x160/0x370
[  132.820302]  [<ffffffff81161db2>] ? d_absolute_path+0x5b/0x7a
[  132.820302]  [<ffffffff812ada30>] process_measurement+0x322/0x404
Reported-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>

The uas driver uses the block layer tag for USB3 stream IDs.  With
blk-mq we can get larger tag numbers that the queue depth, which breaks
this assumption.  A fix is under way for 3.18, but sits on top of
large changes so can't easily be backported.   Set the disable_blk_mq
path so that a uas device can't easily crash the system when using
blk-mq for SCSI.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

Pull ACPI and power management fixes from Rafael Wysocki:
 "These are three regression fixes (cpufreq core, pcc-cpufreq, i915 /
  ACPI) and one trivial fix for a callback return value mismatch in the
  cpufreq integrator driver.

  Specifics:

   - A recent cpufreq core fix went too far and introduced a regression
     in the system suspend code path.  Fix from Viresh Kumar.

   - An ACPI-related commit in the i915 driver that fixed backlight
     problems for some Thinkpads inadvertently broke a Dell machine (in
     3.16).  Fix from Aaron Lu.

   - The pcc-cpufreq driver was broken during the 3.15 cycle by a commit
     that put wait_event() under a spinlock by mistake.  Fix that
     (Rafael J Wysocki).

   - The return value type of integrator_cpufreq_remove() is void, but
     should be int.  Fix from Arnd Bergmann"

* tag 'pm+acpi-3.17-final' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: update 'cpufreq_suspended' after stopping governors
  ACPI / i915: Update the condition to ignore firmware backlight change request
  cpufreq: integrator: fix integrator_cpufreq_remove return type
  cpufreq: pcc-cpufreq: Fix wait_event() under spinlock