This fixes CVE-2016-8650.

If mpi_powm() is given a zero exponent, it wants to immediately return
either 1 or 0, depending on the modulus.  However, if the result was
initalised with zero limb space, no limbs space is allocated and a
NULL-pointer exception ensues.

Fix this by allocating a minimal amount of limb space for the result when
the 0-exponent case when the result is 1 and not touching the limb space
when the result is 0.

This affects the use of RSA keys and X.509 certificates that carry them.

BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: [<ffffffff8138ce5d>] mpi_powm+0x32/0x7e6
PGD 0
Oops: 0002 [#1] SMP
Modules linked in:
CPU: 3 PID: 3014 Comm: keyctl Not tainted 4.9.0-rc6-fscache+ #278
Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
task: ffff8804011944c0 task.stack: ffff880401294000
RIP: 0010:[<ffffffff8138ce5d>]  [<ffffffff8138ce5d>] mpi_powm+0x32/0x7e6
RSP: 0018:ffff880401297ad8  EFLAGS: 00010212
RAX: 0000000000000000 RBX: ffff88040868bec0 RCX: ffff88040868bba0
RDX: ffff88040868b260 RSI: ffff88040868bec0 RDI: ffff88040868bee0
RBP: ffff880401297ba8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000047 R11: ffffffff8183b210 R12: 0000000000000000
R13: ffff8804087c7600 R14: 000000000000001f R15: ffff880401297c50
FS:  00007f7a7918c700(0000) GS:ffff88041fb80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000401250000 CR4: 00000000001406e0
Stack:
 ffff88040868bec0 0000000000000020 ffff880401297b00 ffffffff81376cd4
 0000000000000100 ffff880401297b10 ffffffff81376d12 ffff880401297b30
 ffffffff81376f37 0000000000000100 0000000000000000 ffff880401297ba8
Call Trace:
 [<ffffffff81376cd4>] ? __sg_page_iter_next+0x43/0x66
 [<ffffffff81376d12>] ? sg_miter_get_next_page+0x1b/0x5d
 [<ffffffff81376f37>] ? sg_miter_next+0x17/0xbd
 [<ffffffff8138ba3a>] ? mpi_read_raw_from_sgl+0xf2/0x146
 [<ffffffff8132a95c>] rsa_verify+0x9d/0xee
 [<ffffffff8132acca>] ? pkcs1pad_sg_set_buf+0x2e/0xbb
 [<ffffffff8132af40>] pkcs1pad_verify+0xc0/0xe1
 [<ffffffff8133cb5e>] public_key_verify_signature+0x1b0/0x228
 [<ffffffff8133d974>] x509_check_for_self_signed+0xa1/0xc4
 [<ffffffff8133cdde>] x509_cert_parse+0x167/0x1a1
 [<ffffffff8133d609>] x509_key_preparse+0x21/0x1a1
 [<ffffffff8133c3d7>] asymmetric_key_preparse+0x34/0x61
 [<ffffffff812fc9f3>] key_create_or_update+0x145/0x399
 [<ffffffff812fe227>] SyS_add_key+0x154/0x19e
 [<ffffffff81001c2b>] do_syscall_64+0x80/0x191
 [<ffffffff816825e4>] entry_SYSCALL64_slow_path+0x25/0x25
Code: 56 41 55 41 54 53 48 81 ec a8 00 00 00 44 8b 71 04 8b 42 04 4c 8b 67 18 45 85 f6 89 45 80 0f 84 b4 06 00 00 85 c0 75 2f 41 ff ce <49> c7 04 24 01 00 00 00 b0 01 75 0b 48 8b 41 18 48 83 38 01 0f
RIP  [<ffffffff8138ce5d>] mpi_powm+0x32/0x7e6
 RSP <ffff880401297ad8>
CR2: 0000000000000000
---[ end trace d82015255d4a5d8d ]---

Basically, this is a backport of a libgcrypt patch:

	http://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=patch;h=6e1adb05d290aeeb1c230c763970695f4a538526

Fixes: cdec9cb5 ("crypto: GnuPG based MPI lib - source files (part 1)")
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
cc: linux-ima-devel@lists.sourceforge.net
cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>

We shouldn't free cert->pub->key in x509_cert_parse() because
x509_free_certificate() also does this:
	BUG: Double free or freeing an invalid pointer
	...
	Call Trace:
	 [<ffffffff81896c20>] dump_stack+0x63/0x83
	 [<ffffffff81356571>] kasan_object_err+0x21/0x70
	 [<ffffffff81356ed9>] kasan_report_double_free+0x49/0x60
	 [<ffffffff813561ad>] kasan_slab_free+0x9d/0xc0
	 [<ffffffff81350b7a>] kfree+0x8a/0x1a0
	 [<ffffffff81844fbf>] public_key_free+0x1f/0x30
	 [<ffffffff818455d4>] x509_free_certificate+0x24/0x90
	 [<ffffffff818460bc>] x509_cert_parse+0x2bc/0x300
	 [<ffffffff81846cae>] x509_key_preparse+0x3e/0x330
	 [<ffffffff818444cf>] asymmetric_key_preparse+0x6f/0x100
	 [<ffffffff8178bec0>] key_create_or_update+0x260/0x5f0
	 [<ffffffff8178e6d9>] SyS_add_key+0x199/0x2a0
	 [<ffffffff821d823b>] entry_SYSCALL_64_fastpath+0x1e/0xad
	Object at ffff880110bd1900, in cache kmalloc-512 size: 512
	....
	Freed:
	PID = 2579
	[<ffffffff8104283b>] save_stack_trace+0x1b/0x20
	[<ffffffff813558f6>] save_stack+0x46/0xd0
	[<ffffffff81356183>] kasan_slab_free+0x73/0xc0
	[<ffffffff81350b7a>] kfree+0x8a/0x1a0
	[<ffffffff818460a3>] x509_cert_parse+0x2a3/0x300
	[<ffffffff81846cae>] x509_key_preparse+0x3e/0x330
	[<ffffffff818444cf>] asymmetric_key_preparse+0x6f/0x100
	[<ffffffff8178bec0>] key_create_or_update+0x260/0x5f0
	[<ffffffff8178e6d9>] SyS_add_key+0x199/0x2a0
	[<ffffffff821d823b>] entry_SYSCALL_64_fastpath+0x1e/0xad

Fixes: db6c43bd ("crypto: KEYS: convert public key and digsig asym to the akcipher api")
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

Pull MMC fixes from Ulf Hansson:
 "MMC host:

   - sdhci-of-esdhc: Fix card detection
   - dw_mmc: Fix DMA error path"

* tag 'mmc-v4.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: dw_mmc: fix the error handling for dma operation
  mmc: sdhci-of-esdhc: fixup PRESENT_STATE read

Pull USB fixes from Greg KH:
 "Here are a few small USB fixes and new device ids for 4.9-rc7.

  The majority of these fixes are in the musb driver, fixing a number of
  regressions that have been reported but took a while to resolve. The
  other fixes are all small ones, to resolve other reported minor
  issues.

  All have been in linux-next for a while with no reported issues"

* tag 'usb-4.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: gadget: f_fs: fix wrong parenthesis in ffs_func_req_match()
  phy: twl4030-usb: Fix for musb session bit based PM
  usb: musb: Drop pointless PM runtime code for dsps glue
  usb: musb: Add missing pm_runtime_disable and drop 2430 PM timeout
  usb: musb: Fix PM for hub disconnect
  usb: musb: Fix sleeping function called from invalid context for hdrc glue
  usb: musb: Fix broken use of static variable for multiple instances
  USB: serial: cp210x: add ID for the Zone DPMX
  usb: chipidea: move the lock initialization to core file
  Fix USB CB/CBI storage devices with CONFIG_VMAP_STACK=y
  USB: serial: ftdi_sio: add support for TI CC3200 LaunchPad

Pull HID fixes from Jiri Kosina:

 - DMA-on-stack fixes for a couple drivers, from Benjamin Tissoires

 - small memory sanitization fix for sensor-hub driver, from Song
   Hongyan

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
  HID: hid-sensor-hub: clear memory to avoid random data
  HID: rmi: make transfer buffers DMA capable
  HID: magicmouse: make transfer buffers DMA capable
  HID: lg: make transfer buffers DMA capable
  HID: cp2112: make transfer buffers DMA capable

Otherwise each individual rotator char would be printed in a new line:

(...)
[    0.642350] -
[    0.644374] |
[    0.646367] -
(...)
Signed-off-by: Nicolas Schichan <nicolas.schichan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull NFS client bugfixes from Anna Schumaker:
 "Most of these fix regressions or races, but there is one patch for
  stable that Arnd sent me

  Stable bugfix:
   - Hide array-bounds warning

  Bugfixes:
   - Keep a reference on lock states while checking
   - Handle NFS4ERR_OLD_STATEID in nfs4_reclaim_open_state
   - Don't call close if the open stateid has already been cleared
   - Fix CLOSE rases with OPEN
   - Fix a regression in DELEGRETURN"

* tag 'nfs-for-4.9-4' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  NFSv4.x: hide array-bounds warning
  NFSv4.1: Keep a reference on lock states while checking
  NFSv4.1: Handle NFS4ERR_OLD_STATEID in nfs4_reclaim_open_state
  NFSv4: Don't call close if the open stateid has already been cleared
  NFSv4: Fix CLOSE races with OPEN
  NFSv4.1: Fix a regression in DELEGRETURN

Pull arch/tile bugfix from Chris Metcalf:
 "This fixes a bug that causes reboots after 208 days of uptime :-)"

* 'stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  tile: avoid using clocksource_cyc2ns with absolute cycle count

For large values of "mult" and long uptimes, the intermediate
result of "cycles * mult" can overflow 64 bits.  For example,
the tile platform calls clocksource_cyc2ns with a 1.2 GHz clock;
we have mult = 853, and after 208.5 days, we overflow 64 bits.

Since clocksource_cyc2ns() is intended to be used for relative
cycle counts, not absolute cycle counts, performance is more
importance than accepting a wider range of cycle values.  So,
just use mult_frac() directly in tile's sched_clock().

Commit 4cecf6d4 ("sched, x86: Avoid unnecessary overflow
in sched_clock") by Salman Qazi results in essentially the same
generated code for x86 as this change does for tile.  In fact,
a follow-on change by Salman introduced mult_frac() and switched
to using it, so the C code was largely identical at that point too.

Peter Zijlstra then added mul_u64_u32_shr() and switched x86
to use it.  This is, in principle, better; by optimizing the
64x64->64 multiplies to be 32x32->64 multiplies we can potentially
save some time.  However, the compiler piplines the 64x64->64
multiplies pretty well, and the conditional branch in the generic
mul_u64_u32_shr() causes some bubbles in execution, with the
result that it's pretty much a wash.  If tilegx provided its own
implementation of mul_u64_u32_shr() without the conditional branch,
we could potentially save 3 cycles, but that seems like small gain
for a fair amount of additional build scaffolding; no other platform
currently provides a mul_u64_u32_shr() override, and tile doesn't
currently have an <asm/div64.h> header to put the override in.

Additionally, gcc currently has an optimization bug that prevents
it from recognizing the opportunity to use a 32x32->64 multiply,
and so the result would be no better than the existing mult_frac()
until such time as the compiler is fixed.

For now, just using mult_frac() seems like the right answer.

Cc: stable@kernel.org [v3.4+]
Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>

When user tried to read some fields like hysteresis from IIO sysfs on some
systems, it fails. The reason is that this field is a byte field and caller
of sensor_hub_get_feature() passes a buffer of 4 bytes. Here the function
sensor_hub_get_feature() copies the single byte from the report to the
caller buffer and returns "1" as the number of bytes copied. So caller
can use the return value.

But this is done by multiple callers, so if we just change the
sensor_hub_get_feature so that caller buffer is initialized with 0s
then we don't to change all functions.
Signed-off-by: Song Hongyan <hongyan.song@intel.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Kernel v4.9 strictly enforces DMA capable buffers, so we need to remove
buffers allocated on the stack.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Kernel v4.9 strictly enforces DMA capable buffers, so we need to remove
buffers allocated on the stack.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Kernel v4.9 strictly enforces DMA capable buffers, so we need to remove
buffers allocated on the stack.

[jkosina@suse.cz: fix up second usage of hid_hw_raw_request(), spotted by
 0day build bot]
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Kernel v4.9 strictly enforces DMA capable buffers, so we need to remove
buffers allocated on the stack.

Use a spinlock to prevent concurrent accesses to the buffer.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Pull perf fixes from Ingo Molnar:
 "Six fixes for bugs that were found via fuzzing, and a trivial
  hw-enablement patch for AMD Family-17h CPU PMUs"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/uncore: Allow only a single PMU/box within an events group
  perf/x86/intel: Cure bogus unwind from PEBS entries
  perf/x86: Restore TASK_SIZE check on frame pointer
  perf/core: Fix address filter parser
  perf/x86: Add perf support for AMD family-17h processors
  perf/x86/uncore: Fix crash by removing bogus event_list[] handling for SNB client uncore IMC
  perf/core: Do not set cpuctx->cgrp for unscheduled cgroups

Pull crypto fixes from Herbert Xu:
 "The last push broke algif_hash for all shash implementations, so this
  is a follow-up to fix that.

  This also fixes a problem in the crypto scatterwalk that triggers a
  BUG_ON with certain debugging options due to the new vmalloced-stack
  code"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: scatterwalk - Remove unnecessary aliasing check in map_and_copy
  crypto: algif_hash - Fix result clobbering in recvmsg

Pull thermal management fix from Zhang Rui:
 "We only have one urgent fix this time.

  Commit 3105f234 ("thermal/powerclamp: correct cpu support check"),
  which is shipped in 4.9-rc3, fixed a problem introduced by commit
  b721ca0d ("thermal/powerclamp: remove cpu whitelist").

  But unfortunately, it broke intel_powerclamp driver module auto-
  loading at the same time. Thus we need this change to add back module
  auto-loading for 4.9"

* 'for-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
  thermal/powerclamp: add back module device table

Pull SCSI fixes from James Bottomley:
 "Two small fixes.

  One prevents timeouts on mpt3sas when trying to use the secure erase
  protocol which causes the erase protocol to be aborted. The second is
  a regression in a prior fix which causes all commands to abort during
  PCI extended error recovery, which is incorrect because PCI EEH is
  independent from what's happening on the FC transport"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: qla2xxx: do not abort all commands in the adapter during EEH recovery
  scsi: mpt3sas: Fix secure erase premature termination

Pull clk fixes from Stephen Boyd:
 "A handful of driver fixes.

  The sunxi fixes are for an incorrect clk tree configuration and a bad
  frequency calculation. The other two are fixes for passing the wrong
  pointer in drivers recently converted to clk_hw style registration"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: efm32gg: Pass correct type to hw provider registration
  clk: berlin: Pass correct type to hw provider registration
  clk: sunxi: Fix M factor computation for APB1
  clk: sunxi-ng: sun6i-a31: Force AHB1 clock to use PLL6 as parent

A correct bugfix introduced a harmless warning that shows up with gcc-7:

fs/nfs/callback.c: In function 'nfs_callback_up':
fs/nfs/callback.c:214:14: error: array subscript is outside array bounds [-Werror=array-bounds]

What happens here is that the 'minorversion == 0' check tells the
compiler that we assume minorversion can be something other than 0,
but when CONFIG_NFS_V4_1 is disabled that would be invalid and
result in an out-of-bounds access.

The added check for IS_ENABLED(CONFIG_NFS_V4_1) tells gcc that this
really can't happen, which makes the code slightly smaller and also
avoids the warning.

The bugfix that introduced the warning is marked for stable backports,
we want this one backported to the same releases.

Fixes: 98b0f80c ("NFSv4.x: Fix a refcount leak in nfs_callback_up_net")
Cc: stable@vger.kernel.org # v3.7+
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Pull scheduler fixes from Ingo Molnar:
 "Two fixes for autogroup scheduling, for races when turning the feature
  on/off via /proc/sys/kernel/sched_autogroup_enabled"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/autogroup: Do not use autogroup->tg in zombie threads
  sched/autogroup: Fix autogroup_move_group() to never skip sched_move_task()

Pull x86 fixes from Ingo Molnar:
 "Misc fixes:
   - two fixes to make (very) old Intel CPUs boot reliably
   - fix the intel-mid driver and rename it
   - two KASAN false positive fixes
   - an FPU fix
   - two sysfb fixes
   - two build fixes related to new toolchain versions"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/platform/intel-mid: Rename platform_wdt to platform_mrfld_wdt
  x86/build: Build compressed x86 kernels as PIE when !CONFIG_RELOCATABLE as well
  x86/platform/intel-mid: Register watchdog device after SCU
  x86/fpu: Fix invalid FPU ptrace state after execve()
  x86/boot: Fail the boot if !M486 and CPUID is missing
  x86/traps: Ignore high word of regs->cs in early_fixup_exception()
  x86/dumpstack: Prevent KASAN false positive warnings
  x86/unwind: Prevent KASAN false positive warnings in guess unwinder
  x86/boot: Avoid warning for zero-filling .bss
  x86/sysfb: Fix lfb_size calculation
  x86/sysfb: Add support for 64bit EFI lfb_base

Group validation expects all events to be of the same PMU; however
is_uncore_pmu() is too wide, it matches _all_ uncore events, even
across PMUs.

This triggers failure when we group different events from different
uncore PMUs, like:

  perf stat -vv -e '{uncore_cbox_0/config=0x0334/,uncore_qpi_0/event=1/}' -a sleep 1

Fix is_uncore_pmu() by only matching events to the box at hand.

Note that generic code; ran after this step; will disallow this
mixture of PMU events.
Reported-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vince@deater.net>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20161118125354.GQ3117@twins.programming.kicks-ass.netSigned-off-by: Ingo Molnar <mingo@kernel.org>

Vince Weaver reported that perf_fuzzer + KASAN detects that PEBS event
unwinds sometimes do 'weird' things. In particular, we seemed to be
ending up unwinding from random places on the NMI stack.

While it was somewhat expected that the event record BP,SP would not
match the interrupt BP,SP in that the interrupt is strictly later than
the record event, it was overlooked that it could be on an already
overwritten stack.

Therefore, don't copy the recorded BP,SP over the interrupted BP,SP
when we need stack unwinds.

Note that its still possible the unwind doesn't full match the actual
event, as its entirely possible to have done an (I)RET between record
and interrupt, but on average it should still point in the general
direction of where the event came from. Also, it's the best we can do,
considering.

The particular scenario that triggered the bogus NMI stack unwind was
a PEBS event with very short period, upon enabling the event at the
tail of the PMI handler (FREEZE_ON_PMI is not used), it instantly
triggers a record (while still on the NMI stack) which in turn
triggers the next PMI. This then causes back-to-back NMIs and we'll
try and unwind the stack-frame from the last NMI, which obviously is
now overwritten by our own.
Analyzed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davej@codemonkey.org.uk <davej@codemonkey.org.uk>
Cc: dvyukov@google.com <dvyukov@google.com>
Cc: stable@vger.kernel.org
Fixes: ca037701 ("perf, x86: Add PEBS infrastructure")
Link: http://lkml.kernel.org/r/20161117171731.GV3157@twins.programming.kicks-ass.netSigned-off-by: Ingo Molnar <mingo@kernel.org>

The following commit:

  75925e1a ("perf/x86: Optimize stack walk user accesses")

... switched from copy_from_user_nmi() to __copy_from_user_nmi() with a manual
access_ok() check.

Unfortunately, copy_from_user_nmi() does an explicit check against TASK_SIZE,
whereas the access_ok() uses whatever the current address limit of the task is.

We are getting NMIs when __probe_kernel_read() has switched to KERNEL_DS, and
then see vmalloc faults when we access what looks like pointers into vmalloc
space:

  [] WARNING: CPU: 3 PID: 3685731 at arch/x86/mm/fault.c:435 vmalloc_fault+0x289/0x290
  [] CPU: 3 PID: 3685731 Comm: sh Tainted: G        W       4.6.0-5_fbk1_223_gdbf0f40 #1
  [] Call Trace:
  []  <NMI>  [<ffffffff814717d1>] dump_stack+0x4d/0x6c
  []  [<ffffffff81076e43>] __warn+0xd3/0xf0
  []  [<ffffffff81076f2d>] warn_slowpath_null+0x1d/0x20
  []  [<ffffffff8104a899>] vmalloc_fault+0x289/0x290
  []  [<ffffffff8104b5a0>] __do_page_fault+0x330/0x490
  []  [<ffffffff8104b70c>] do_page_fault+0xc/0x10
  []  [<ffffffff81794e82>] page_fault+0x22/0x30
  []  [<ffffffff81006280>] ? perf_callchain_user+0x100/0x2a0
  []  [<ffffffff8115124f>] get_perf_callchain+0x17f/0x190
  []  [<ffffffff811512c7>] perf_callchain+0x67/0x80
  []  [<ffffffff8114e750>] perf_prepare_sample+0x2a0/0x370
  []  [<ffffffff8114e840>] perf_event_output+0x20/0x60
  []  [<ffffffff8114aee7>] ? perf_event_update_userpage+0xc7/0x130
  []  [<ffffffff8114ea01>] __perf_event_overflow+0x181/0x1d0
  []  [<ffffffff8114f484>] perf_event_overflow+0x14/0x20
  []  [<ffffffff8100a6e3>] intel_pmu_handle_irq+0x1d3/0x490
  []  [<ffffffff8147daf7>] ? copy_user_enhanced_fast_string+0x7/0x10
  []  [<ffffffff81197191>] ? vunmap_page_range+0x1a1/0x2f0
  []  [<ffffffff811972f1>] ? unmap_kernel_range_noflush+0x11/0x20
  []  [<ffffffff814f2056>] ? ghes_copy_tofrom_phys+0x116/0x1f0
  []  [<ffffffff81040d1d>] ? x2apic_send_IPI_self+0x1d/0x20
  []  [<ffffffff8100411d>] perf_event_nmi_handler+0x2d/0x50
  []  [<ffffffff8101ea31>] nmi_handle+0x61/0x110
  []  [<ffffffff8101ef94>] default_do_nmi+0x44/0x110
  []  [<ffffffff8101f13b>] do_nmi+0xdb/0x150
  []  [<ffffffff81795187>] end_repeat_nmi+0x1a/0x1e
  []  [<ffffffff8147daf7>] ? copy_user_enhanced_fast_string+0x7/0x10
  []  [<ffffffff8147daf7>] ? copy_user_enhanced_fast_string+0x7/0x10
  []  [<ffffffff8147daf7>] ? copy_user_enhanced_fast_string+0x7/0x10
  []  <<EOE>>  <IRQ>  [<ffffffff8115d05e>] ? __probe_kernel_read+0x3e/0xa0

Fix this by moving the valid_user_frame() check to before the uaccess
that loads the return address and the pointer to the next frame.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Fixes: 75925e1a ("perf/x86: Optimize stack walk user accesses")
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Exactly because for_each_thread() in autogroup_move_group() can't see it
and update its ->sched_task_group before _put() and possibly free().

So the exiting task needs another sched_move_task() before exit_notify()
and we need to re-introduce the PF_EXITING (or similar) check removed by
the previous change for another reason.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hartsjc@redhat.com
Cc: vbendel@redhat.com
Cc: vlovejoy@redhat.com
Link: http://lkml.kernel.org/r/20161114184612.GA15968@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

The PF_EXITING check in task_wants_autogroup() is no longer needed. Remove
it, but see the next patch.

However the comment is correct in that autogroup_move_group() must always
change task_group() for every thread so the sysctl_ check is very wrong;
we can race with cgroups and even sys_setsid() is not safe because a task
running with task_group() == ag->tg must participate in refcounting:

	int main(void)
	{
		int sctl = open("/proc/sys/kernel/sched_autogroup_enabled", O_WRONLY);

		assert(sctl > 0);
		if (fork()) {
			wait(NULL); // destroy the child's ag/tg
			pause();
		}

		assert(pwrite(sctl, "1\n", 2, 0) == 2);
		assert(setsid() > 0);
		if (fork())
			pause();

		kill(getppid(), SIGKILL);
		sleep(1);

		// The child has gone, the grandchild runs with kref == 1
		assert(pwrite(sctl, "0\n", 2, 0) == 2);
		assert(setsid() > 0);

		// runs with the freed ag/tg
		for (;;)
			sleep(1);

		return 0;
	}

crashes the kernel. It doesn't really need sleep(1), it doesn't matter if
autogroup_move_group() actually frees the task_group or this happens later.
Reported-by: Vern Lovejoy <vlovejoy@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hartsjc@redhat.com
Cc: vbendel@redhat.com
Link: http://lkml.kernel.org/r/20161114184609.GA15965@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

The aliasing check in map_and_copy is no longer necessary because
the IPsec ESP code no longer provides an IV that points into the
actual request data.  As this check is now triggering BUG checks
due to the vmalloced stack code, I'm removing it.
Reported-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Recently an init call was added to hash_recvmsg so as to reset
the hash state in case a sendmsg call was never made.

Unfortunately this ended up clobbering the result if the previous
sendmsg was done with a MSG_MORE flag.  This patch fixes it by
excluding that case when we make the init call.

Fixes: a8348bca ("algif_hash - Fix NULL hash crash with shash")
Reported-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Pull apparmor bugfix from James Morris:
 "This has a fix for a policy replacement bug that is fairly serious for
  apache mod_apparmor users, as it results in the wrong policy being
  applied on an network facing service"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  apparmor: fix change_hat not finding hat after policy replacement

Pull sparc fixes from David Miller:

 1) With modern networking cards we can run out of 32-bit DMA space, so
    support 64-bit DMA addressing when possible on sparc64. From Dave
    Tushar.

 2) Some signal frame validation checks are inverted on sparc32, fix
    from Andreas Larsson.

 3) Lockdep tables can get too large in some circumstances on sparc64,
    add a way to adjust the size a bit. From Babu Moger.

 4) Fix NUMA node probing on some sun4v systems, from Thomas Tai.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: drop duplicate header scatterlist.h
  lockdep: Limit static allocations if PROVE_LOCKING_SMALL is defined
  config: Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc
  sunbmac: Fix compiler warning
  sunqe: Fix compiler warnings
  sparc64: Enable 64-bit DMA
  sparc64: Enable sun4v dma ops to use IOMMU v2 APIs
  sparc64: Bind PCIe devices to use IOMMU v2 service
  sparc64: Initialize iommu_map_table and iommu_pool
  sparc64: Add ATU (new IOMMU) support
  sparc64: Add FORCE_MAX_ZONEORDER and default to 13
  sparc64: fix compile warning section mismatch in find_node()
  sparc32: Fix inverted invalid_frame_pointer checks on sigreturns
  sparc64: Fix find_node warning if numa node cannot be found

Pull networking fixes from David Miller:

 1) Clear congestion control state when changing algorithms on an
    existing socket, from Florian Westphal.

 2) Fix register bit values in altr_tse_pcs portion of stmmac driver,
    from Jia Jie Ho.

 3) Fix PTP handling in stammc driver for GMAC4, from Giuseppe
    CAVALLARO.

 4) Fix udplite multicast delivery handling, it ignores the udp_table
    parameter passed into the lookups, from Pablo Neira Ayuso.

 5) Synchronize the space estimated by rtnl_vfinfo_size and the space
    actually used by rtnl_fill_vfinfo. From Sabrina Dubroca.

 6) Fix memory leak in fib_info when splitting nodes, from Alexander
    Duyck.

 7) If a driver does a napi_hash_del() explicitily and not via
    netif_napi_del(), it must perform RCU synchronization as needed. Fix
    this in virtio-net and bnxt drivers, from Eric Dumazet.

 8) Likewise, it is not necessary to invoke napi_hash_del() is we are
    also doing neif_napi_del() in the same code path. Remove such calls
    from be2net and cxgb4 drivers, also from Eric Dumazet.

 9) Don't allocate an ID in peernet2id_alloc() if the netns is dead,
    from WANG Cong.

10) Fix OF node and device struct leaks in of_mdio, from Johan Hovold.

11) We cannot cache routes in ip6_tunnel when using inherited traffic
    classes, from Paolo Abeni.

12) Fix several crashes and leaks in cpsw driver, from Johan Hovold.

13) Splice operations cannot use freezable blocking calls in AF_UNIX,
    from WANG Cong.

14) Link dump filtering by master device and kind support added an error
    in loop index updates during the dump if we actually do filter, fix
    from Zhang Shengju.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (59 commits)
  tcp: zero ca_priv area when switching cc algorithms
  net: l2tp: Treat NET_XMIT_CN as success in l2tp_eth_dev_xmit
  ethernet: stmmac: make DWMAC_STM32 depend on it's associated SoC
  tipc: eliminate obsolete socket locking policy description
  rtnl: fix the loop index update error in rtnl_dump_ifinfo()
  l2tp: fix racy SOCK_ZAPPED flag check in l2tp_ip{,6}_bind()
  net: macb: add check for dma mapping error in start_xmit()
  rtnetlink: fix FDB size computation
  netns: fix get_net_ns_by_fd(int pid) typo
  af_unix: conditionally use freezable blocking calls in read
  net: ethernet: ti: cpsw: fix fixed-link phy probe deferral
  net: ethernet: ti: cpsw: add missing sanity check
  net: ethernet: ti: cpsw: fix secondary-emac probe error path
  net: ethernet: ti: cpsw: fix of_node and phydev leaks
  net: ethernet: ti: cpsw: fix deferred probe
  net: ethernet: ti: cpsw: fix mdio device reference leak
  net: ethernet: ti: cpsw: fix bad register access in probe error path
  net: sky2: Fix shutdown crash
  cfg80211: limit scan results cache size
  net sched filters: pass netlink message flags in event notification
  ...

We need to zero out the private data area when application switches
connection to different algorithm (TCP_CONGESTION setsockopt).

When congestion ops get assigned at connect time everything is already
zeroed because sk_alloc uses GFP_ZERO flag.  But in the setsockopt case
this contains whatever previous cc placed there.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

The tc could return NET_XMIT_CN as one congestion notification, but
it does not mean the packe is lost. Other modules like ipvlan,
macvlan, and others treat NET_XMIT_CN as success too.
So l2tp_eth_dev_xmit should add the NET_XMIT_CN check.
Signed-off-by: Gao Feng <gfree.wind@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

While walking the list of lock_states, keep a reference on each
nfs4_lock_state to be checked, otherwise the lock state could be removed
while the check performs TEST_STATEID and possible FREE_STATEID.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

There's not much point, except compile test, enabling the stmmac
platform drivers unless the STM32 SoC is enabled. It's not
useful without it.
Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 3105f234 replaced module
cpu id table with a cpu feature check, which is logically correct.
But we need the module device table to allow module auto loading.

Cc: stable@vger.kernel.org # 4.8
Fixes:3105f234 thermal/powerclamp: correct cpu support check
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

The token table passed into match_token() must be null-terminated, which
it currently is not in the perf's address filter string parser, as caught
by Vince's perf_fuzzer and KASAN.

It doesn't blow up otherwise because of the alignment padding of the table
to the next element in the .rodata, which is luck.

Fixing by adding a null-terminator to the token table.
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dvyukov@google.com
Cc: stable@vger.kernel.org # v4.7+
Fixes: 375637bc ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/877f81f264.fsf@ashishki-desk.ger.corp.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

When dma->start is failed,then it has to fall back to PIO mode
for current transfer.

But Host controller was already set to bits relevant to DMA operation.
If needs to use the PIO mode, Host controller has to stop the DMA
operation. (It's more stable than now.)

When it occurred error, it's not running any request.

Fixes: 3fc7eaef ("mmc: dw_mmc: Add external dma interface support")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Cc: <stable@vger.kernel.org> # v4.3+
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Rename the watchdog platform library file to explicitly show that is used only
on Intel Merrifield platforms.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161118172723.179761-1-andriy.shevchenko@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>