The Montgomery Multiply, Montgomery Square, and Multiple-Precision
Multiply instructions work by loading a combination of the floating
point and multiple register windows worth of integer registers
with the inputs.

These values are 64-bit.  But for 32-bit userland processes we only
save the low 32-bits of each integer register during a register spill.
This is because the register window save area is in the user stack and
has a fixed layout.

Therefore, the only way to use these instruction in 32-bit mode is to
perform the following sequence:

1) Load the top-32bits of a choosen integer register with a sentinel,
   say "-1".  This will be in the outer-most register window.

   The idea is that we're trying to see if the outer-most register
   window gets spilled, and thus the 64-bit values were truncated.

2) Load all the inputs for the montmul/montsqr/mpmul instruction,
   down to the inner-most register window.

3) Execute the opcode.

4) Traverse back up to the outer-most register window.

5) Check the sentinel, if it's still "-1" store the results.
   Otherwise retry the entire sequence.

This retry is extremely troublesome.  If you're just unlucky and an
interrupt or other trap happens, it'll push that outer-most window to
the stack and clear the sentinel when we restore it.

We could retry forever and never make forward progress if interrupts
arrive at a fast enough rate (consider perf events as one example).
So we have do limited retries and fallback to software which is
extremely non-deterministic.

Luckily it's very straightforward to provide a mechanism to let
32-bit applications use a 64-bit stack.  Stacks in 64-bit mode are
biased by 2047 bytes, which means that the lowest bit is set in the
actual %sp register value.

So if we see bit zero set in a 32-bit application's stack we treat
it like a 64-bit stack.

Runtime detection of such a facility is tricky, and cumbersome at
best.  For example, just trying to use a biased stack and seeing if it
works is hard to recover from (the signal handler will need to use an
alt stack, plus something along the lines of longjmp).  Therefore, we
add a system call to report a bitmask of arch specific features like
this in a cheap and less hairy way.

With help from Andy Polyakov.
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull USB fixes from Greg Kroah-Hartman:
 "Here are a bunch of USB fixes for the 3.7-rc tree.

  There's a lot of small USB serial driver fixes, and one larger one
  (the mos7840 driver changes are mostly just moving code around to fix
  problems.) Thanks to Johan Hovold for finding the problems and fixing
  them all up.

  Other than those, there is the usual new device ids, xhci bugfixes,
  and gadget driver fixes, nothing out of the ordinary.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'usb-3.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (49 commits)
  xhci: trivial: Remove assigned but unused ep_ctx.
  xhci: trivial: Remove assigned but unused slot_ctx.
  xhci: Fix missing break in xhci_evaluate_context_result.
  xhci: Fix potential NULL ptr deref in command cancellation.
  ehci: Add yet-another Lucid nohandoff pci quirk
  ehci: fix Lucid nohandoff pci quirk to be more generic with BIOS versions
  USB: mos7840: fix port_probe flow
  USB: mos7840: fix port-data memory leak
  USB: mos7840: remove invalid disconnect handling
  USB: mos7840: remove NULL-urb submission
  USB: qcserial: fix interface-data memory leak in error path
  USB: option: fix interface-data memory leak in error path
  USB: ipw: fix interface-data memory leak in error path
  USB: mos7840: fix port-device leak in error path
  USB: mos7840: fix urb leak at release
  USB: sierra: fix port-data memory leak
  USB: sierra: fix memory leak in probe error path
  USB: sierra: fix memory leak in attach error path
  USB: usb-wwan: fix multiple memory leaks in error paths
  USB: keyspan: fix NULL-pointer dereferences and memory leaks
  ...

Pull serial fix from Greg Kroah-Hartman:
 "Here is one patch, a revert of a omap serial driver patch that was
  causing problems, for your 3.7-rc tree.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'tty-3.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "serial: omap: fix software flow control"

Pull staging driver fixes from Greg Kroah-Hartman:
 "Here are some staging driver fixes for your 3.7-rc tree.

  Nothing major here, a number of iio driver fixups that were causing
  problems, some comedi driver bugfixes, and a bunch of tidspbridge
  warning squashing and other regressions fixed from the 3.6 release.

  All have been in the linux-next releases for a bit.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'staging-3.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (32 commits)
  staging: tidspbridge: delete unused mmu functions
  staging: tidspbridge: ioremap physical address of the stack segment in shm
  staging: tidspbridge: ioremap dsp sync addr
  staging: tidspbridge: change type to __iomem for per and core addresses
  staging: tidspbridge: drop const from custom mmu implementation
  staging: tidspbridge: request the right irq for mmu
  staging: ipack: add missing include (implicit declaration of function 'kfree')
  staging: ramster: depends on NET
  staging: omapdrm: fix allocation size for page addresses array
  staging: zram: Fix handling of incompressible pages
  Staging: android: binder: Allow using highmem for binder buffers
  Staging: android: binder: Fix memory leak on thread/process exit
  staging: comedi: ni_labpc: fix possible NULL deref during detach
  staging: comedi: das08: fix possible NULL deref during detach
  staging: comedi: amplc_pc263: fix possible NULL deref during detach
  staging: comedi: amplc_pc236: fix possible NULL deref during detach
  staging: comedi: amplc_pc236: fix invalid register access during detach
  staging: comedi: amplc_dio200: fix possible NULL deref during detach
  staging: comedi: 8255_pci: fix possible NULL deref during detach
  staging: comedi: ni_daq_700: fix dio subdevice regression
  ...

Pull driver core fixes from Greg Kroah-Hartman:
 "Here are a number of firmware core fixes for 3.7, and some other minor
  fixes.  And some documentation updates thrown in for good measure.

  All have been in the linux-next tree for a while.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'driver-core-3.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  Documentation:Chinese translation of Documentation/arm64/memory.txt
  Documentation:Chinese translation of Documentation/arm64/booting.txt
  Documentation:Chinese translation of Documentation/IRQ.txt
  firmware loader: document kernel direct loading
  sysfs: sysfs_pathname/sysfs_add_one: Use strlcat() instead of strcat()
  dynamic_debug: Remove unnecessary __used
  firmware loader: sync firmware cache by async_synchronize_full_domain
  firmware loader: let direct loading back on 'firmware_buf'
  firmware loader: fix one reqeust_firmware race
  firmware loader: cancel uncache work before caching firmware

Pull char/misc driver fixes from Greg Kroah-Hartman:
 "Here are some driver fixes for 3.7.  They include extcon driver fixes,
  a hyper-v bugfix, and two other minor driver fixes.

  All of these have been in the linux-next releases for a while.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'char-misc-3.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  sonypi: suspend/resume callbacks should be conditionally compiled on CONFIG_PM_SLEEP
  Drivers: hv: Cleanup error handling in vmbus_open()
  extcon : register for cable interest by cable name
  extcon: trivial: kfree missed from remove path
  extcon: driver model release call not needed
  extcon: MAX77693: Add platform data for MUIC device to initialize registers
  extcon: max77693: Use max77693_update_reg for rmw operations
  extcon: Fix kerneldoc for extcon_set_cable_state and extcon_set_cable_state_
  extcon: adc-jack: Add missing MODULE_LICENSE
  extcon: adc-jack: Fix checking return value of request_any_context_irq
  extcon: Fix return value in extcon_register_interest()
  extcon: unregister compat link on cleanup
  extcon: Unregister compat class at module unload to fix oops
  extcon: optimising the check_mutually_exclusive function
  extcon: standard cable names definition and declaration changed
  extcon-max8997: remove usage of ret in max8997_muic_handle_charger_type_detach
  extcon: Remove duplicate inclusion of extcon.h header file

In commit 800179c9 ("This adds symlink and hardlink restrictions to
the Linux VFS"), the new link protections were enabled by default, in
the hope that no actual application would care, despite it being
technically against legacy UNIX (and documented POSIX) behavior.

However, it does turn out to break some applications.  It's rare, and
it's unfortunate, but it's unacceptable to break existing systems, so
we'll have to default to legacy behavior.

In particular, it has broken the way AFD distributes files, see

  http://www.dwd.de/AFD/

along with some legacy scripts.

Distributions can end up setting this at initrd time or in system
scripts: if you have security problems due to link attacks during your
early boot sequence, you have bigger problems than some kernel sysctl
setting. Do:

	echo 1 > /proc/sys/fs/protected_symlinks
	echo 1 > /proc/sys/fs/protected_hardlinks

to re-enable the link protections.

Alternatively, we may at some point introduce a kernel config option
that sets these kinds of "more secure but not traditional" behavioural
options automatically.
Reported-by: Nick Bowler <nbowler@elliptictech.com>
Reported-by: Holger Kiehl <Holger.Kiehl@dwd.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org # v3.6
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull sound fixes from Takashi Iwai:
 "Slightly a high amount of commits come from Adrian Knoth's HDSPM
  driver fixes.  Other than that, all small trival fixes or quirks that
  are pretty driver-specific."

* tag 'sound-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ASoC: wm8994: Only enable extra BCLK cycles when required
  ALSA: als3000: check for the kzalloc return value
  ALSA: sound/isa/opti9xx/miro.c: eliminate possible double free
  ALSA: hda - Fix silent headphone output from Toshiba P200
  ALSA: hdspm - Fix coding style in CTL_ELEM macros
  ALSA: hdspm - Fix typo in kcontrol element on RME MADI cards
  ALSA: hdspm - Fix sync_in detection on AES/AES32
  ALSA: hdspm - Fix sync_in reporting on RME MADI cards
  ALSA: hdspm - Also report autosync_sample_rate on MADI and MADIface
  ALSA: hdspm - Fix reported autosync_sample_rate
  ALSA: hdspm - Fix sync check reporting on all RME HDSPM cards
  ALSA: hdspm - Report external rate in slave mode on PCI MADI
  ALSA: hdspm - Allow DDS/Varispeed to be set from userspace
  ALSA: hda - add dock support for Thinkpad T430
  ASoC: ux500_msp_i2s: Fix devm_* and return code merge error
  ASoC: Ux500: Dispose of device nodes correctly

Pull DMA-mapping revert from Marek Szyprowski:
 "Due to my mistake, my previous pull request (merged as commit
  cff7b8ba: "Merge branch 'fixes_for_linus' ..") contained a patch
  which is aimed for v3.8 and lacks its dependences.  This pull request
  reverts it and fixes build break of ARM architecture."

* 'fixes_for_linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping:
  Revert "ARM: dma-mapping: support debug_dma_mapping_error"

Pull x86 fixes from Ingo Molnar:
 "This fixes a couple of nasty page table initialization bugs which were
  causing kdump regressions.  A clean rearchitecturing of the code is in
  the works - meanwhile these are reverts that restore the
  best-known-working state of the kernel.

  There's also EFI fixes and other small fixes."

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, mm: Undo incorrect revert in arch/x86/mm/init.c
  x86: efi: Turn off efi_enabled after setup on mixed fw/kernel
  x86, mm: Find_early_table_space based on ranges that are actually being mapped
  x86, mm: Use memblock memory loop instead of e820_RAM
  x86, mm: Trim memory in memblock to be page aligned
  x86/irq/ioapic: Check for valid irq_cfg pointer in smp_irq_move_cleanup_interrupt
  x86/efi: Fix oops caused by incorrect set_memory_uc() usage
  x86-64: Fix page table accounting
  Revert "x86/mm: Fix the size calculation of mapping tables"
  MAINTAINERS: Add EFI git repository location

Pull perf fixes from Ingo Molnar:
 "Most of the kernel diffstat relates to a group of Intel P6 and KNC
  (Xeon-Phi Knights Corner) PMU driver fixes, neither of which is in
  heavy use, so we took the fixes.

  The rest is diverse smallish fixes to the tooling and kernel side."

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86: Remove unused variable in nhmex_rbox_alter_er()
  perf/x86: Enable overflow on Intel KNC with a custom knc_pmu_handle_irq()
  perf/x86: Remove cpuc->enable check on Intl KNC event enable/disable
  perf/x86: Make Intel KNC use full 40-bit width of counters
  perf/x86/uncore: Handle pci_read_config_dword() errors
  perf/x86: Remove P6 cpuc->enabled check
  perf/x86: Update/fix generic events on P6 PMU
  perf/x86: Fix P6 FP_ASSIST event constraint
  perf, cpu hotplug: Use cached value of smp_processor_id()
  perf, cpu hotplug: Run CPU_STARTING notifiers with irqs disabled
  x86/perf: Fix virtualization sanity check
  perf test: Fix exclude_guest parse events tests
  perf tools: do not flush maps on COMM for perf report
  perf help: Fix --help for builtins
  perf trace: Check if sample raw_data field is set
  perf trace: Validate syscall id before growing syscall table

Pull btrfs fixes from Chris Mason:
 "This has our series of fixes for the next rc.  The biggest batch is
  from Jan Schmidt, fixing up some problems in our subvolume quota code
  and fixing btrfs send/receive to work with the new extended inode
  refs."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: do not bug when we fail to commit the transaction
  Btrfs: fix memory leak when cloning root's node
  Btrfs: Use btrfs_update_inode_fallback when creating a snapshot
  Btrfs: Send: preserve ownership (uid and gid) also for symlinks.
  Btrfs: fix deadlock caused by the nested chunk allocation
  btrfs: Return EINVAL when length to trim is less than FSB
  Btrfs: fix memory leak in btrfs_quota_enable()
  Btrfs: send correct rdev and mode in btrfs-send
  Btrfs: extended inode refs support for send mechanism
  Btrfs: Fix wrong error handling code
  Fix a sign bug causing invalid memory access in the ino_paths ioctl.
  Btrfs: comment for loop in tree_mod_log_insert_move
  Btrfs: fix extent buffer reference for tree mod log roots
  Btrfs: determine level of old roots
  Btrfs: tree mod log's old roots could still be part of the tree
  Btrfs: fix a tree mod logging issue for root replacement operations
  Btrfs: don't put removals from push_node_left into tree mod log twice

Merge tag 'efi-for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent

Pull EFI fixes from Matt Fleming:

 "Fix oops with EFI variables on mixed 32/64-bit firmware/kernels and
  document EFI git repository location on kernel.org."

Conflicts:
	arch/x86/include/asm/efi.h
Signed-off-by: Ingo Molnar <mingo@kernel.org>

This reverts commit 871ae57a, which is
scheduled for v3.8 and accidently got into v3.7-rc series.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

Pull drm radeon fixes from Dave Airlie:
 "Just radeon fixes in this one:
   - some new PCI IDs
   - ATPX regression fix
   - async VM regression fixes
   - some module options fixes"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/radeon: fix ATPX regression in acpi rework
  drm/radeon: fix ATPX function documentation
  drm/radeon: move the retry to gem_object_create
  drm/radeon: move size limits to gem_object_create.
  drm/radeon: use vzalloc for gart pages
  drm/radeon: fix and simplify pot argument checks v3
  drm/radeon: fix header size estimation in VM code
  drm/radeon: remove set_page check from VM code
  drm/radeon: fix si_set_page v2
  drm/radeon: fix cayman_vm_set_page v2
  drm/radeon: fix PFP sync in vm_flush
  drm/radeon: add error output if VM CS fails on cayman
  drm/radeon: give each backlight a unique id
  drm/radeon: fix sparse warning
  drm/radeon: add some new SI PCI ids

Pull NFS bugfixes from Trond Myklebust:

 - Fix the NFSv2/v3 kernel statd protocol, which broke due to net
   namespace related changes.

 - Fix a number of races in the SUNRPC TCP disconnect/reconnect code.

* tag 'nfs-for-3.7-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  LOCKD: Clear ln->nsm_clnt only when ln->nsm_users is zero
  LOCKD: fix races in nsm_client_get
  SUNRPC: Get rid of the xs_error_report socket callback
  SUNRPC: Prevent races in xs_abort_connection()
  Revert "SUNRPC: Ensure we close the socket on EPIPE errors too..."
  SUNRPC: Clear the connect flag when socket state is TCP_CLOSE_WAIT

Alex writes:
"Fixes pull request for radeon.  The main things here are
fixing a ATPX regression from the acpi rework, fixing some
fallout from the async VM work, and fixing some module options
that were broken in certain cases.  Other than that, mainly
just bug fixes."

* 'drm-fixes-3.7' of git://people.freedesktop.org/~agd5f/linux:
  drm/radeon: fix ATPX regression in acpi rework
  drm/radeon: fix ATPX function documentation
  drm/radeon: move the retry to gem_object_create
  drm/radeon: move size limits to gem_object_create.
  drm/radeon: use vzalloc for gart pages
  drm/radeon: fix and simplify pot argument checks v3
  drm/radeon: fix header size estimation in VM code
  drm/radeon: remove set_page check from VM code
  drm/radeon: fix si_set_page v2
  drm/radeon: fix cayman_vm_set_page v2
  drm/radeon: fix PFP sync in vm_flush
  drm/radeon: add error output if VM CS fails on cayman
  drm/radeon: give each backlight a unique id
  drm/radeon: fix sparse warning
  drm/radeon: add some new SI PCI ids

Merge misc fixes from Andrew Morton:
 "18 total.  15 fixes and some updates to a device_cgroup patchset which
  bring it up to date with the version which I should have merged in the
  first place."

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (18 patches)
  fs/compat_ioctl.c: VIDEO_SET_SPU_PALETTE missing error check
  gen_init_cpio: avoid stack overflow when expanding
  drivers/rtc/rtc-imxdi.c: add missing spin lock initialization
  mm, numa: avoid setting zone_reclaim_mode unless a node is sufficiently distant
  pidns: limit the nesting depth of pid namespaces
  drivers/dma/dw_dmac: make driver's endianness configurable
  mm/mmu_notifier: allocate mmu_notifier in advance
  tools/testing/selftests/epoll/test_epoll.c: fix build
  UAPI: fix tools/vm/page-types.c
  mm/page_alloc.c:alloc_contig_range(): return early for err path
  rbtree: include linux/compiler.h for definition of __always_inline
  genalloc: stop crashing the system when destroying a pool
  backlight: ili9320: add missing SPI dependency
  device_cgroup: add proper checking when changing default behavior
  device_cgroup: stop using simple_strtoul()
  device_cgroup: rename deny_all to behavior
  cgroup: fix invalid rcu dereference
  mm: fix XFS oops due to dirty pages without buffers on s390

Decode multitouch reports from the touch sensor of the Cintiq 24HD
touch.
Signed-off-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Like our other pen-and-touch products, the Cintiq 24HD touch needs data
to be shared between its two sensors to facilitate proximity-based palm
rejection.

Unlike other tablets that report sensor data through separate interfaces
of the same USB device, the Cintiq 24HD touch has separate USB devices
that are connected to an internal USB hub.

This patch makes it possible to designate the USB VID/PID of the other
device so that the two may share data.  To ensure we don't accidentally
link to a sensor from a physically separate device (if several have been
plugged in), we limit the search to siblings (i.e., devices directly
connected to the same hub).
Signed-off-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If one includes documentation for an external tool, it should be
correct.  This is not:

1. Overriding the input to rngd should typically be neither
   necessary nor desired.  This is especially so since newer
   versions of rngd support a number of different *types* of sources.
2. The default kernel-exported device is called /dev/hwrng not
   /dev/hwrandom nor /dev/hw_random (both of which were used in the
   past; however, kernel and udev seem to have converged on
   /dev/hwrng.)

Overall it is better if the documentation for rngd is kept with rngd
rather than in a kernel Makefile.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull ARM fixes from Russell King:
 "A random collection of various fixes, mainly from Arnd and a few other
  people.  Not thing really stands out here."

* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
  ARM: drop experimental status for hotplug and Thumb2
  ARM: 7560/1: SMP_TWD: use DIV_ROUND_CLOSEST() for periodic mode
  ARM: 7559/1: smp: switch away from the idmap before updating init_mm.mm_count
  ARM: 7556/1: perf: fix updated event period in response to PERF_EVENT_IOC_PERIOD
  ARM: 7555/1: kexec: fix segment memory addresses check
  ARM: warnings in arch/arm/include/asm/uaccess.h
  ARM: binfmt_flat: unused variable 'persistent'
  ARM: be really quiet when building with 'make -s'
  ARM: pass -marm to gcc by default for both C and assembler
  ARM: Xen: fix initial build problems
  ARM: export default read_current_timer
  ARM: Fix another build warning in arch/arm/mm/alignment.c
  ARM: export set_irq_flags
  ARM: kprobes: make more tests conditional

Pull CMA and DMA-mapping fixes from Marek Szyprowski:
 "This consists mainly of a set of one-liner fixes and cleanups for a
  few minor issues identified in both Contiguous Memory Allocator code
  and ARM DMA-mapping subsystem."

* 'fixes_for_linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping:
  ARM: mm: Remove unused arm_vmregion priv field
  ARM: dma-mapping: fix build warning in __dma_alloc()
  ARM: dma-mapping: support debug_dma_mapping_error
  mm: cma: alloc_contig_range: return early for err path
  drivers: cma: Fix wrong CMA selected region size default value
  drivers: dma-coherent: Fix typo in dma_mmap_from_coherent documentation
  drivers: dma-contiguous: Don't redefine SZ_1M

Commit

    844ab6f9 x86, mm: Find_early_table_space based on ranges that are actually being mapped

added back some lines back wrongly that has been removed in commit

    7b16bbf9 Revert "x86/mm: Fix the size calculation of mapping tables"

remove them again.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/CAE9FiQW_vuaYQbmagVnxT2DGsYc=9tNeAbdBq53sYkitPOwxSQ@mail.gmail.comAcked-by: Jacob Shin <jacob.shin@amd.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

The compat ioctl for VIDEO_SET_SPU_PALETTE was missing an error check
while converting ioctl arguments.  This could lead to leaking kernel
stack contents into userspace.

Patch extracted from existing fix in grsecurity.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: David Miller <davem@davemloft.net>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: PaX Team <pageexec@freemail.hu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix possible overflow of the buffer used for expanding environment
variables when building file list.

In the extremely unlikely case of an attacker having control over the
environment variables visible to gen_init_cpio, control over the
contents of the file gen_init_cpio parses, and gen_init_cpio was built
without compiler hardening, the attacker can gain arbitrary execution
control via a stack buffer overflow.

  $ cat usr/crash.list
  file foo ${BIG}${BIG}${BIG}${BIG}${BIG}${BIG} 0755 0 0
  $ BIG=$(perl -e 'print "A" x 4096;') ./usr/gen_init_cpio usr/crash.list
  *** buffer overflow detected ***: ./usr/gen_init_cpio terminated

This also replaces the space-indenting with tabs.

Patch based on existing fix extracted from grsecurity.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: PaX Team <pageexec@freemail.hu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Jan Luebbe <jlu@pengutronix.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Roland Stigge <stigge@antcom.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Roland Stigge <stigge@antcom.de>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 957f822a ("mm, numa: reclaim from all nodes within reclaim
distance") caused zone_reclaim_mode to be set for all systems where two
nodes are within RECLAIM_DISTANCE of each other.  This is the opposite
of what we actually want: zone_reclaim_mode should be set if two nodes
are sufficiently distant.
Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Julian Wollrath <jwollrath@web.de>
Tested-by: Julian Wollrath <jwollrath@web.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Patrik Kullman <patrik.kullman@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

'struct pid' is a "variable sized struct" - a header with an array of
upids at the end.

The size of the array depends on a level (depth) of pid namespaces.  Now a
level of pidns is not limited, so 'struct pid' can be more than one page.

Looks reasonable, that it should be less than a page.  MAX_PIS_NS_LEVEL is
not calculated from PAGE_SIZE, because in this case it depends on
architectures, config options and it will be reduced, if someone adds a
new fields in struct pid or struct upid.

I suggest to set MAX_PIS_NS_LEVEL = 32, because it saves ability to expand
"struct pid" and it's more than enough for all known for me use-cases.
When someone finds a reasonable use case, we can add a config option or a
sysctl parameter.

In addition it will reduce the effect of another problem, when we have
many nested namespaces and the oldest one starts dying.
zap_pid_ns_processe will be called for each namespace and find_vpid will
be called for each process in a namespace.  find_vpid will be called
minimum max_level^2 / 2 times.  The reason of that is that when we found a
bit in pidmap, we can't determine this pidns is top for this process or it
isn't.

vpid is a heavy operation, so a fork bomb, which create many nested
namespace, can make a system inaccessible for a long time.  For example my
system becomes inaccessible for a few minutes with 4000 processes.

[akpm@linux-foundation.org: return -EINVAL in response to excessive nesting, not -ENOMEM]
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The dw_dmac driver was originally developed for avr32 to be used with the
Synopsys DesignWare AHB DMA controller.  Starting from 2.6.38, access to
the device's i/o memory was done with the little-endian readl/writel
functions(1)

This broke the driver for the avr32 platform, because it needs big
(native) endian accessors.  This patch makes the endianness configurable
using 'DW_DMAC_BIG_ENDIAN_IO', which will default be true for AVR32

I submitted this patch before(2) but then waited for Andy to finish other
changes to the same module(3).

(1) https://patchwork.kernel.org/patch/608211
(2) https://lkml.org/lkml/2012/8/26/148
(3) https://lkml.org/lkml/2012/9/21/173Signed-off-by: Hein Tibosch <hein_tibosch@yahoo.es>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Havard Skinnemoen <havard@skinnemoen.net>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

While allocating mmu_notifier with parameter GFP_KERNEL, swap would start
to work in case of tight available memory.  Eventually, that would lead to
a deadlock while the swap deamon swaps anonymous pages.  It was caused by
commit e0f3c3f7 ("mm/mmu_notifier: init notifier if necessary").

  =================================
  [ INFO: inconsistent lock state ]
  3.7.0-rc1+ #518 Not tainted
  ---------------------------------
  inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage.
  kswapd0/35 [HC0[0]:SC0[0]:HE1:SE1] takes:
   (&mapping->i_mmap_mutex){+.+.?.}, at: page_referenced+0x9c/0x2e0
  {RECLAIM_FS-ON-W} state was registered at:
     mark_held_locks+0x86/0x150
     lockdep_trace_alloc+0x67/0xc0
     kmem_cache_alloc_trace+0x33/0x230
     do_mmu_notifier_register+0x87/0x180
     mmu_notifier_register+0x13/0x20
     kvm_dev_ioctl+0x428/0x510
     do_vfs_ioctl+0x98/0x570
     sys_ioctl+0x91/0xb0
     system_call_fastpath+0x16/0x1b
  irq event stamp: 825
  hardirqs last  enabled at (825): _raw_spin_unlock_irq+0x30/0x60
  hardirqs last disabled at (824): _raw_spin_lock_irq+0x19/0x80
  softirqs last  enabled at (0): copy_process+0x630/0x17c0
  softirqs last disabled at (0): (null)
  ...

Simply back out the above commit, which was a small performance
optimization.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Reported-by: Andrea Righi <andrea@betterlinux.com>
Tested-by: Andrea Righi <andrea@betterlinux.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Sagi Grimberg <sagig@mellanox.co.il>
Cc: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Latest Linus head run of "make selftests" in the tools directory failed
with references to undefined variables.  Reference was to
'write_thread_data' which is the name of a struct that is being used, not
the variable itself.  Change reference so it points to the variable.
Signed-off-by: Daniel Hazelton <dshadowwolf@gmail.com>
Cc: "Paton J. Lewis" <palewis@adobe.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix tools/vm/page-types.c to use the UAPI variant of linux/kernel-page-flags.h
lest the following error appear:

  In file included from page-types.c:38:0:
    ../../include/linux/kernel-page-flags.h:4:42: fatal error:
    uapi/linux/kernel-page-flags.h: No such file or directory
Reported-by: Daniel Hazelton <dshadowwolf@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Fengguang Wu <fengguang.wu@intel.com>
Tested-by: Daniel Hazelton <dshadowwolf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If start_isolate_page_range() failed, unset_migratetype_isolate() has been
done inside it.
Signed-off-by: Bob Liu <lliubbo@gmail.com>
Cc: Ni zhan Chen <nizhan.chen@gmail.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rb_erase_augmented() is a static function annotated with
__always_inline.  This causes a compile failure when attempting to use
the rbtree implementation as a library (e.g.  kvm tool):

  rbtree_augmented.h:125:24: error: expected `=', `,', `;', `asm' or `__attribute__' before `void'

Include linux/compiler.h in rbtree_augmented.h so that the __always_inline
macro is resolved correctly.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Reviewed-by: Michel Lespinasse <walken@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The genalloc code uses the bitmap API from include/linux/bitmap.h and
lib/bitmap.c, which is based on long values.  Both bitmap_set from
lib/bitmap.c and bitmap_set_ll, which is the lockless version from
genalloc.c, use BITMAP_LAST_WORD_MASK to set the first bits in a long in
the bitmap.

That one uses (1 << bits) - 1, 0b111, if you are setting the first three
bits.  This means that the API counts from the least significant bits
(LSB from now on) to the MSB.  The LSB in the first long is bit 0, then.
The same works for the lookup functions.

The genalloc code uses longs for the bitmap, as it should.  In
include/linux/genalloc.h, struct gen_pool_chunk has unsigned long
bits[0] as its last member.  When allocating the struct, genalloc should
reserve enough space for the bitmap.  This should be a proper number of
longs that can fit the amount of bits in the bitmap.

However, genalloc allocates an integer number of bytes that fit the
amount of bits, but may not be an integer amount of longs.  9 bytes, for
example, could be allocated for 70 bits.

This is a problem in itself if the Least Significat Bit in a long is in
the byte with the largest address, which happens in Big Endian machines.
This means genalloc is not allocating the byte in which it will try to
set or check for a bit.

This may end up in memory corruption, where genalloc will try to set the
bits it has not allocated.  In fact, genalloc may not set these bits
because it may find them already set, because they were not zeroed since
they were not allocated.  And that's what causes a BUG when
gen_pool_destroy is called and check for any set bits.

What really happens is that genalloc uses kmalloc_node with __GFP_ZERO
on gen_pool_add_virt.  With SLAB and SLUB, this means the whole slab
will be cleared, not only the requested bytes.  Since struct
gen_pool_chunk has a size that is a multiple of 8, and slab sizes are
multiples of 8, we get lucky and allocate and clear the right amount of
bytes.

Hower, this is not the case with SLOB or with older code that did memset
after allocating instead of using __GFP_ZERO.

So, a simple module as this (running 3.6.0), will cause a crash when
rmmod'ed.

  [root@phantom-lp2 foo]# cat foo.c
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/genalloc.h>

  MODULE_LICENSE("GPL");
  MODULE_VERSION("0.1");

  static struct gen_pool *foo_pool;

  static __init int foo_init(void)
  {
          int ret;
          foo_pool = gen_pool_create(10, -1);
          if (!foo_pool)
                  return -ENOMEM;
          ret = gen_pool_add(foo_pool, 0xa0000000, 32 << 10, -1);
          if (ret) {
                  gen_pool_destroy(foo_pool);
                  return ret;
          }
          return 0;
  }

  static __exit void foo_exit(void)
  {
          gen_pool_destroy(foo_pool);
  }

  module_init(foo_init);
  module_exit(foo_exit);
  [root@phantom-lp2 foo]# zcat /proc/config.gz | grep SLOB
  CONFIG_SLOB=y
  [root@phantom-lp2 foo]# insmod ./foo.ko
  [root@phantom-lp2 foo]# rmmod foo
  ------------[ cut here ]------------
  kernel BUG at lib/genalloc.c:243!
  cpu 0x4: Vector: 700 (Program Check) at [c0000000bb0e7960]
      pc: c0000000003cb50c: .gen_pool_destroy+0xac/0x110
      lr: c0000000003cb4fc: .gen_pool_destroy+0x9c/0x110
      sp: c0000000bb0e7be0
     msr: 8000000000029032
    current = 0xc0000000bb0e0000
    paca    = 0xc000000006d30e00   softe: 0        irq_happened: 0x01
      pid   = 13044, comm = rmmod
  kernel BUG at lib/genalloc.c:243!
  [c0000000bb0e7ca0] d000000004b00020 .foo_exit+0x20/0x38 [foo]
  [c0000000bb0e7d20] c0000000000dff98 .SyS_delete_module+0x1a8/0x290
  [c0000000bb0e7e30] c0000000000097d4 syscall_exit+0x0/0x94
  --- Exception: c00 (System Call) at 000000800753d1a0
  SP (fffd0b0e640) is in userspace
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Benjamin Gaignard <benjamin.gaignard@stericsson.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add this missing SPI dependency and prevent the driver from building
without SPI, because functions of the spi driver are used in this
driver.

  drivers/video/backlight/ili9320.c:51: undefined reference to `spi_sync'

Also, a prompt string for CONFIG_LCD_ILI9320 is added for explicit
selection.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Before changing a group's default behavior to ALLOW, we must check if
its parent's behavior is also ALLOW.
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: James Morris <jmorris@namei.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Convert the code to use kstrtou32() instead of simple_strtoul() which is
deprecated.  The real size of the variables are u32, so use kstrtou32
instead of kstrtoul
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: James Morris <jmorris@namei.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This was done in a v2 patch but v1 ended up being committed.  The
variable name is less confusing and stores the default behavior when no
matching exception exists.
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: James Morris <jmorris@namei.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>