ALSA: hda/conexant - Correct vendor IDs for new codecs

commit 2d825fd82eb765412a558a56e193b77117d56699 upstream.

Never trust datasheet...

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Weng Meiling <wengmeiling.weng@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ALSA: hda - Add stereo-dmic fixup for Acer Aspire One 522

commit 63a077e27648b4043b1ca1b4e29f0c42d99616b6 upstream.

Acer Aspire One 522 has the infamous digital mic unit that needs the
phase inversion fixup for stereo.

Bugzilla: https://bugzilla.novell.com/show_bug.cgi?id=715737

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Weng Meiling <wengmeiling.weng@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ALSA: hda - Fix oops caused by recent commit "Fix internal mic for Lenovo Ideapad U300s"

commit 83b0c6ba999643ee8ad6329f26e1cdc870e1a920 upstream.

Make sure we don't dereference the "quirk" pointer when it is null.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Weng Meiling <wengmeiling.weng@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ALSA: hda - Add inverted internal mic quirk for Lenovo IdeaPad U310

commit e4db0952e542090c605fd41d31d761f1b4624f4a upstream.

The Lenovo IdeaPad U310 has an internal mic where the right channel
is phase inverted.

Signed-off-by: Felix Kaechele <felix@fetzig.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Weng Meiling <wengmeiling.weng@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ALSA: HDA: Add inverted internal mic quirk for Lenovo S205

commit b3c5dce81584391af8b6dedb0647e65c17aab3a2 upstream.

The Lenovo Ideapad S205 has an internal mic where the right channel
is phase inverted.

BugLink: https://bugs.launchpad.net/bugs/884652
Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Weng Meiling <wengmeiling.weng@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thinkpad-acpi: fix issuing duplicated key events for brightness up/down

commit ff413195e830541afeae469fc866ecd0319abd7e upstream.

The tp_features.bright_acpimode will not be set correctly for brightness
control because ACPI_VIDEO_HID will not be located in ACPI. As a result,
a duplicated key event will always be sent. acpi_video_backlight_support()
is sufficient to detect standard ACPI brightness control.

Signed-off-by: Alex Hung <alex.hung@canonical.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: Andreas Sturmlechner <andreas.sturmlechner@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

PCI: shpchp: Use per-slot workqueues to avoid deadlock

commit f652e7d2916fe2fcf9e7d709aa5b7476b431e2dd upstream.

When we have an SHPC-capable bridge with a second SHPC-capable bridge
below it, pushing the upstream bridge's attention button causes a
deadlock.

The deadlock happens because we use the shpchp_wq workqueue to run
shpchp_pushbutton_thread(), which uses shpchp_disable_slot() to remove
devices below the upstream bridge.  When we remove the downstream bridge,
we call shpc_remove(), the shpchp driver's .remove() method.  That calls
flush_workqueue(shpchp_wq), which deadlocks because the
shpchp_pushbutton_thread() work item is still running.

This patch avoids the deadlock by creating a workqueue for every slot
and removing the single shared workqueue.

Here's the call path that leads to the deadlock:

  shpchp_queue_pushbutton_work
    queue_work(shpchp_wq) # shpchp_pushbutton_thread
    ...

  shpchp_pushbutton_thread
    shpchp_disable_slot
      remove_board
        shpchp_unconfigure_device
          pci_stop_and_remove_bus_device
            ...
              shpc_remove # shpchp driver .remove method
                hpc_release_ctlr
                  cleanup_slots
                    flush_workqueue(shpchp_wq)

This change is based on code inspection, since we don't have hardware
with this topology.

Based-on-patch-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
[hq: Backported to 3.4: adjust context]
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mac80211: introduce IEEE80211_HW_TEARDOWN_AGGR_ON_BAR_FAIL

commit 5b632fe85ec82e5c43740b52e74c66df50a37db3 upstream.

Commit f0425beda4d404a6e751439b562100b902ba9c98 "mac80211: retry sending
failed BAR frames later instead of tearing down aggr" caused regression
on rt2x00 hardware (connection hangs). This regression was fixed by
commit be03d4a45c09ee5100d3aaaedd087f19bc20d01 "rt2x00: Don't let
mac80211 send a BAR when an AMPDU subframe fails". But the latter
commit caused yet another problem reported in
https://bugzilla.kernel.org/show_bug.cgi?id=42828#c22

After long discussion in this thread:
http://mid.gmane.org/20121018075615.GA18212@redhat.com
and testing various alternative solutions, which failed on one or other
setup, we have no other good fix for the issues like just revert both
mentioned earlier commits.

To do not affect other hardware which benefit from commit
f0425beda4d404a6e751439b562100b902ba9c98, instead of reverting it,
introduce flag that when used will restore mac80211 behaviour before
the commit.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
[replaced link with mid.gmane.org that has message-id]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
[hq: Backported to 3.4: adjust context]
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

e1000e: DoS while TSO enabled caused by link partner with small MSS

commit d821a4c4d11ad160925dab2bb009b8444beff484 upstream.

With a low enough MSS on the link partner and TSO enabled locally, the
networking stack can periodically send a very large (e.g.  64KB) TCP
message for which the driver will attempt to use more Tx descriptors than
are available by default in the Tx ring.  This is due to a workaround in
the code that imposes a limit of only 4 MSS-sized segments per descriptor
which appears to be a carry-over from the older e1000 driver and may be
applicable only to some older PCI or PCIx parts which are not supported in
e1000e.  When the driver gets a message that is too large to fit across the
configured number of Tx descriptors, it stops the upper stack from queueing
any more and gets stuck in this state.  After a timeout, the upper stack
assumes the adapter is hung and calls the driver to reset it.

Remove the unnecessary limitation of using up to only 4 MSS-sized segments
per Tx descriptor, and put in a hard failure test to catch when attempting
to check for message sizes larger than would fit in the whole Tx ring.
Refactor the remaining logic that limits the size of data per Tx descriptor
from a seemingly arbitrary 8KB to a limit based on the dynamic size of the
Tx packet buffer as described in the hardware specification.

Also, fix the logic in the check for space in the Tx ring for the next
largest possible packet after the current one has been successfully queued
for transmit, and use the appropriate defines for default ring sizes in
e1000_probe instead of magic values.

This issue goes back to the introduction of e1000e in 2.6.24 when it was
split off from e1000.

Reported-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

can: c_can: Set reserved bit in IFx_MASK2 to 1 on write

commit 2bd3bc4e8472424f1a6009825397639a8968920a upstream.

According to C_CAN documentation, the reserved bit in IFx_MASK2 register is
fixed 1.

Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

intel_idle: Don't register CPU notifier if we are not running.

commit 6f8c2e7933679f54b6478945dc72e59ef9a3d5e0 upstream.

The 'intel_idle_probe' probes the CPU and sets the CPU notifier.
But if later on during the module initialization we fail (say
in cpuidle_register_driver), we stop loading, but we neglect
to unregister the CPU notifier.  This means that during CPU
hotplug events the system will fail:

calling  intel_idle_init+0x0/0x326 @ 1
intel_idle: MWAIT substates: 0x1120
intel_idle: v0.4 model 0x2A
intel_idle: lapic_timer_reliable_states 0xffffffff
intel_idle: intel_idle yielding to none
initcall intel_idle_init+0x0/0x326 returned -19 after 14 usecs

... some time later, offlining and onlining a CPU:

cpu 3 spinlock event irq 62
BUG: unable to ] __cpuidle_register_device+0x1c/0x120
PGD 99b8b067 PUD 99b95067 PMD 0
Oops: 0000 [#1] SMP
Modules linked in: xen_evtchn nouveau mxm_wmi wmi radeon ttm i915 fbcon tileblit font atl1c bitblit softcursor drm_kms_helper video xen_blkfront xen_netfront fb_sys_fops sysimgblt sysfillrect syscopyarea xenfs xen_privcmd mperf
CPU 0
Pid: 2302, comm: udevd Not tainted 3.8.0-rc3upstream-00249-g09ad159 #1 MSI MS-7680/H61M-P23 (MS-7680)
RIP: e030:[<ffffffff814d956c>]  [<ffffffff814d956c>] __cpuidle_register_device+0x1c/0x120
RSP: e02b:ffff88009dacfcb8  EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff880105380000 RCX: 000000000000001c
RDX: 0000000000000000 RSI: 0000000000000055 RDI: ffff880105380000
RBP: ffff88009dacfce8 R08: ffffffff81a4f048 R09: 0000000000000008
R10: 0000000000000008 R11: 0000000000000000 R12: ffff880105380000
R13: 00000000ffffffdd R14: 0000000000000000 R15: ffffffff81a523d0
FS:  00007f37bd83b7a0(0000) GS:ffff880105200000(0000) knlGS:0000000000000000
CS:  e033 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000008 CR3: 00000000a09ea000 CR4: 0000000000042660
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process udevd (pid: 2302, threadinfo ffff88009dace000, task ffff88009afb47f0)
Stack:
 ffffffff8107f2d0 ffffffff810c2fb7 ffff88009dacfce8 00000000ffffffea
 ffff880105380000 00000000ffffffdd ffff88009dacfd08 ffffffff814d9882
 0000000000000003 ffff880105380000 ffff88009dacfd28 ffffffff81340afd
Call Trace:
 [<ffffffff8107f2d0>] ? collect_cpu_info_local+0x30/0x30
 [<ffffffff810c2fb7>] ? __might_sleep+0xe7/0x100
 [<ffffffff814d9882>] cpuidle_register_device+0x32/0x70
 [<ffffffff81340afd>] intel_idle_cpu_init+0xad/0x110
 [<ffffffff81340bc8>] cpu_hotplug_notify+0x68/0x80
 [<ffffffff8166023d>] notifier_call_chain+0x4d/0x70
 [<ffffffff810bc369>] __raw_notifier_call_chain+0x9/0x10
 [<ffffffff81094a4b>] __cpu_notify+0x1b/0x30
 [<ffffffff81652cf7>] _cpu_up+0x103/0x14b
 [<ffffffff81652e18>] cpu_up+0xd9/0xec
 [<ffffffff8164a254>] store_online+0x94/0xd0
 [<ffffffff814122fb>] dev_attr_store+0x1b/0x20
 [<ffffffff81216404>] sysfs_write_file+0xf4/0x170
 [<ffffffff811a1024>] vfs_write+0xb4/0x130
 [<ffffffff811a17ea>] sys_write+0x5a/0xa0
 [<ffffffff816643a9>] system_call_fastpath+0x16/0x1b
Code: 03 18 00 c9 c3 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 48 83 ec 30 48 89 5d e8 4c 89 65 f0 48 89 fb 4c 89 6d f8 e8 84 08 00 00 <48> 8b 78 08 49 89 c4 e8 f8 7f c1 ff 89 c2 b8 ea ff ff ff 84 d2
RIP  [<ffffffff814d956c>] __cpuidle_register_device+0x1c/0x120
 RSP <ffff88009dacfcb8>

This patch fixes that by moving the CPU notifier registration
as the last item to be done by the module.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[bwh: Backported to 3.2: notifier is registered only if we do not have ARAT]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

regulator: max8998: Ensure enough delay time for max8998_set_voltage_buck_time_sel

commit e8d9897ff064b1683c11c15ea1296a67a45d77b0 upstream.

commit 81d0a6ae7befb24c06f4aa4856af7f8d1f612171 upstream.

Use DIV_ROUND_UP to prevent truncation by integer division issue.
This ensures we return enough delay time.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
[bwh: Backported to 3.2: delay is done by driver, not returned to the caller]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

regulator: max8997: Use uV in voltage_map_desc

commit bc3b7756b5ff66828acf7bc24f148d28b8d61108 upstream.

Current code does integer division (min_vol = min_uV / 1000) before pass
min_vol to max8997_get_voltage_proper_val().
So it is possible min_vol is truncated to a smaller value.

For example, if the request min_uV is 800900 for ldo.
min_vol = 800900 / 1000 = 800 (mV)
Then max8997_get_voltage_proper_val returns 800 mV for this case which is lower
than the requested voltage.

Use uV rather than mV in voltage_map_desc to prevent truncation by integer
division.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
[bwh: Backported to 3.2:
 - Adjust context
 - voltage_map_desc also has an n_bits field]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

i915: ensure that VGA plane is disabled

commit 0fde901f1ddd2ce0e380a6444f1fb7ca555859e9 upstream.

Some broken systems (like HP nc6120) in some cases, usually after LID
close/open, enable VGA plane, making display unusable (black screen on LVDS,
some strange mode on VGA output). We used to disable VGA plane only once at
startup. Now we also check, if VGA plane is still disabled while changing
mode, and fix that if something changed it.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=57434
Signed-off-by: Krzysztof Mazur <krzysiek@podlesie.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[bwh: Backported to 3.2: intel_modeset_setup_hw_state() does not
 exist, so call i915_redisable_vga() directly from intel_lid_notify()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

i82975x_edac: Fix dimm label initialization

commit 479696840239e0cc43efb3c917bdcad2174d2215 upstream.

The driver has only 4 hardcoded labels, but allows much more memory.
Fix it by removing the hardcoded logic, using snprintf() instead.

[   19.833972] general protection fault: 0000 [#1] SMP
[   19.837733] Modules linked in: i82975x_edac(+) edac_core firewire_ohci firewire_core crc_itu_t nouveau mxm_wmi wmi video i2c_algo_bit drm_kms_helper ttm drm i2c_core
[   19.837733] CPU 0
[   19.837733] Pid: 390, comm: udevd Not tainted 3.6.1-1.fc17.x86_64.debug #1 Dell Inc.                 Precision WorkStation 390    /0MY510
[   19.837733] RIP: 0010:[<ffffffff813463a8>]  [<ffffffff813463a8>] strncpy+0x18/0x30
[   19.837733] RSP: 0018:ffff880078535b68  EFLAGS: 00010202
[   19.837733] RAX: ffff880069fa9708 RBX: ffff880078588000 RCX: ffff880069fa9708
[   19.837733] RDX: 000000000000001f RSI: 5f706f5f63616465 RDI: ffff880069fa9708
[   19.837733] RBP: ffff880078535b68 R08: ffff880069fa9727 R09: 000000000000fffe
[   19.837733] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000003
[   19.837733] R13: 0000000000000000 R14: ffff880069fa9290 R15: ffff880079624a80
[   19.837733] FS:  00007f3de01ee840(0000) GS:ffff88007c400000(0000) knlGS:0000000000000000
[   19.837733] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   19.837733] CR2: 00007f3de00b9000 CR3: 0000000078dbc000 CR4: 00000000000007f0
[   19.837733] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   19.837733] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[   19.837733] Process udevd (pid: 390, threadinfo ffff880078534000, task ffff880079642450)
[   19.837733] Stack:
[   19.837733]  ffff880078535c18 ffffffffa017c6b8 00040000816d627f ffff880079624a88
[   19.837733]  ffffc90004cd6000 ffff880079624520 ffff88007ac21148 0000000000000000
[   19.837733]  0000000000000000 0004000000000000 feda000078535bc8 ffffffff810d696d
[   19.837733] Call Trace:
[   19.837733]  [<ffffffffa017c6b8>] i82975x_init_one+0x2e6/0x3e6 [i82975x_edac]
...

Fix bug reported at:
https://bugzilla.redhat.com/show_bug.cgi?id=848149
And, very likely:
https://bbs.archlinux.org/viewtopic.php?id=148033
https://bugzilla.kernel.org/show_bug.cgi?id=47171

Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
[bwh: Backported to 3.2:
 - Adjust context
 - Use csrow->channels[chan].label not csrow->channels[chan]->dimm->label]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

MISC: hpilo, remove pci_disable_device

commit bcdee04ea7ae0406ae69094f6df1aacb66a69a0b upstream.

pci_disable_device(pdev) used to be in pci remove function. But this
PCI device has two functions with interrupt lines connected to a
single pin. The other one is a USB host controller. So when we disable
the PIN there e.g. by rmmod hpilo, the controller stops working. It is
because the interrupt link is disabled in ACPI since it is not
refcounted yet. See acpi_pci_link_free_irq called from
acpi_pci_irq_disable.

It is not the best solution whatsoever, but as a workaround until the
ACPI irq link refcounting is sorted out this should fix the reported
errors.

References: https://lkml.org/lkml/2008/11/4/535

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Grant Grundler <grundler@parisc-linux.org>
Cc: Nobin Mathew <nobin.mathew@gmail.com>
Cc: Robert Hancock <hancockr@shaw.ca>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Altobelli <david.altobelli@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

floppy: properly handle failure on add_disk loop

commit d60e7ec18c3fb2cbf90969ccd42889eb2d03aef9 upstream.

On floppy initialization, if something failed inside the loop we call
add_disk, there was no cleanup of previous iterations in the error
handling.

Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Input: synaptics - adjust threshold for treating position values as negative

commit 824efd37415961d38821ecbd9694e213fb2e8b32 upstream.

Commit c039450 (Input: synaptics - handle out of bounds values from the
hardware) caused any hardware reported values over 7167 to be treated as
a wrapped-around negative value. It turns out that some firmware uses
the value 8176 to indicate a finger near the edge of the touchpad whose
actual position cannot be determined. This value now gets treated as
negative, which can cause pointer jumps and broken edge scrolling on
these machines.

I only know of one touchpad which reports negative values, and this
hardware never reports any value lower than -8 (i.e. 8184). Moving the
threshold for treating a value as negative up to 8176 should work fine
then for any hardware we currently know about, and since we're dealing
with unspecified behavior it's probably the best we can do. The special
8176 value is also likely to result in sudden jumps in position, so
let's also clamp this to the maximum specified value for the axis.

BugLink: http://bugs.launchpad.net/bugs/1046512
https://bugzilla.kernel.org/show_bug.cgi?id=46371

Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Tested-by: Alan Swanson <swanson@ukfsn.org>
Tested-by: Arteom <arutemus@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

UBI: erase free PEB with bitflip in EC header

commit 193819cf2e6e395b1e1be2d36785dc5563a6edca upstream.

Without this patch, these PEB are not scrubbed until we put data in them.
Bitflip can accumulate latter and we can loose the EC header (but VID header
should be intact and allow to recover data).

Signed-off-by: Matthieu Castet <matthieu.castet@parrot.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
[bwh: Backported to 3.2: adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Staging: zram: Fix access of NULL pointer

commit 46a51c80216cb891f271ad021f59009f34677499 upstream.

This patch fixes the bug in reset_store caused by accessing NULL pointer.

The bdev gets its value from bdget_disk() which could fail when memory
pressure is severe and hence can return NULL because allocation of
inode in bdget could fail.

Hence, this patch introduces a check for bdev to prevent reference to a
NULL pointer in the later part of the code. It also removes unnecessary
check of bdev for fsync_bdev().

Acked-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

zram: allow request end to coincide with disksize

commit 75c7caf5a052ffd8db3312fa7864ee2d142890c4 upstream.

Pass valid_io_request() checks if request end coincides with disksize
(end equals bound), only fail if we attempt to read beyond the bound.

mkfs.ext2 produces numerous errors:
[ 2164.632747] quiet_error: 1 callbacks suppressed
[ 2164.633260] Buffer I/O error on device zram0, logical block 153599
[ 2164.633265] lost page write due to I/O error on zram0

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

zram: avoid access beyond the zram device

commit 12a7ad3b810e77137d0caf97a6dd97591e075b30 upstream.

Function valid_io_request() should verify the entire request are within
the zram device address range. Otherwise it may cause invalid memory
access when accessing/modifying zram->meta->table[index] because the
'index' is out of range. Then it may access non-exist memory, randomly
modify memory belong to other subsystems, which is hard to track down.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

zram: destroy all devices on error recovery path in zram_init()

commit 39a9b8ac9333e4268ecff7da6c9d1ab3823ff243 upstream.

On error recovery path of zram_init(), it leaks the zram device object
causing the failure. So change create_device() to free allocated
resources on error path.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

zram: avoid invalid memory access in zram_exit()

commit 6030ea9b35971a4200062f010341ab832e878ac9 upstream.

Memory for zram->disk object may have already been freed after returning
from destroy_device(zram), then it's unsafe for zram_reset_device(zram)
to access zram->disk again.

We can't solve this bug by flipping the order of destroy_device(zram)
and zram_reset_device(zram), that will cause deadlock issues to the
zram sysfs handler.

So fix it by holding an extra reference to zram->disk before calling
destroy_device(zram).

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

zram: Fix deadlock bug in partial read/write

commit 7e5a5104c6af709a8d97d5f4711e7c917761d464 upstream.

Now zram allocates new page with GFP_KERNEL in zram I/O path
if IO is partial. Unfortunately, It may cause deadlock with
reclaim path like below.

write_page from fs
fs_lock
allocation(GFP_KERNEL)
reclaim
pageout
write_page from fs
fs_lock <-- deadlock

This patch fixes it by using GFP_NOIO.  In read path, we
reorganize code flow so that kmap_atomic is called after the
GFP_NOIO allocation.

Acked-by: Jerome Marchand <jmarchand@redhat.com>
Acked-by: Nitin Gupta <ngupta@vflare.org>
[ penberg@kernel.org: don't use GFP_ATOMIC ]
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: no reordering is needed in the read path]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dm thin: fix discard corruption

commit f046f89a99ccfd9408b94c653374ff3065c7edb3 upstream.

Fix a bug in dm_btree_remove that could leave leaf values with incorrect
reference counts.  The effect of this was that removal of a shared block
could result in the space maps thinking the block was no longer used.
More concretely, if you have a thin device and a snapshot of it, sending
a discard to a shared region of the thin could corrupt the snapshot.

Thinp uses a 2-level nested btree to store it's mappings.  This first
level is indexed by thin device, and the second level by logical
block.

Often when we're removing an entry in this mapping tree we need to
rebalance nodes, which can involve shadowing them, possibly creating a
copy if the block is shared.  If we do create a copy then children of
that node need to have their reference counts incremented.  In this
way reference counts percolate down the tree as shared trees diverge.

The rebalance functions were incrementing the children at the
appropriate time, but they were always assuming the children were
internal nodes.  This meant the leaf values (in our case packed
block/flags entries) were not being incremented.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
[bwh: Backported to 3.2: bump target version numbers from 1.0.1 to 1.0.2]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
[xr: Backported to 3.4: bump target version numbers to 1.1.1]
Signed-off-by: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dm mpath: fix race condition between multipath_dtr and pg_init_done

commit 954a73d5d3073df2231820c718fdd2f18b0fe4c9 upstream.

Whenever multipath_dtr() is happening we must prevent queueing any
further path activation work.  Implement this by adding a new
'pg_init_disabled' flag to the multipath structure that denotes future
path activation work should be skipped if it is set.  By disabling
pg_init and then re-enabling in flush_multipath_work() we also avoid the
potential for pg_init to be initiated while suspending an mpath device.

Without this patch a race condition exists that may result in a kernel
panic:

1) If after pg_init_done() decrements pg_init_in_progress to 0, a call
   to wait_for_pg_init_completion() assumes there are no more pending path
   management commands.
2) If pg_init_required is set by pg_init_done(), due to retryable
   mode_select errors, then process_queued_ios() will again queue the
   path activation work.
3) If free_multipath() completes before activate_path() work is called a
   NULL pointer dereference like the following can be seen when
   accessing members of the recently destructed multipath:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000090
RIP: 0010:[<ffffffffa003db1b>]  [<ffffffffa003db1b>] activate_path+0x1b/0x30 [dm_multipath]
[<ffffffff81090ac0>] worker_thread+0x170/0x2a0
[<ffffffff81096c80>] ? autoremove_wake_function+0x0/0x40

[switch to disabling pg_init in flush_multipath_work & header edits by Mike Snitzer]
Signed-off-by: Shiva Krishna Merla <shivakrishna.merla@netapp.com>
Reviewed-by: Krishnasamy Somasundaram <somasundaram.krishnasamy@netapp.com>
Tested-by: Speagle Andy <Andy.Speagle@netapp.com>
Acked-by: Junichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
[bwh: Backported to 3.2:
 - Adjust context
 - Bump version to 1.3.2 not 1.6.0]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
[xr: Backported to 3.4: Adjust context]
Signed-off-by: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dm snapshot: avoid snapshot space leak on crash

commit 230c83afdd9cd384348475bea1e14b80b3b6b1b8 upstream.

There is a possible leak of snapshot space in case of crash.

The reason for space leaking is that chunks in the snapshot device are
allocated sequentially, but they are finished (and stored in the metadata)
out of order, depending on the order in which copying finished.

For example, supposed that the metadata contains the following records
SUPERBLOCK
METADATA (blocks 0 ... 250)
DATA 0
DATA 1
DATA 2
...
DATA 250

Now suppose that you allocate 10 new data blocks 251-260. Suppose that
copying of these blocks finish out of order (block 260 finished first
and the block 251 finished last). Now, the snapshot device looks like
this:
SUPERBLOCK
METADATA (blocks 0 ... 250, 260, 259, 258, 257, 256)
DATA 0
DATA 1
DATA 2
...
DATA 250
DATA 251
DATA 252
DATA 253
DATA 254
DATA 255
METADATA (blocks 255, 254, 253, 252, 251)
DATA 256
DATA 257
DATA 258
DATA 259
DATA 260

Now, if the machine crashes after writing the first metadata block but
before writing the second metadata block, the space for areas DATA 250-255
is leaked, it contains no valid data and it will never be used in the
future.

This patch makes dm-snapshot complete exceptions in the same order they
were allocated, thus fixing this bug.

Note: when backporting this patch to the stable kernel, change the version
field in the following way:
* if version in the stable kernel is {1, 11, 1}, change it to {1, 12, 0}
* if version in the stable kernel is {1, 10, 0} or {1, 10, 1}, change it
  to {1, 10, 2}
Userspace reads the version to determine if the bug was fixed, so the
version change is needed.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
[xr: Backported to 3.4: adjust version]
Signed-off-by: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

nfsd: nfsd_open: when dentry_open returns an error do not propagate as struct file

commit e4daf1ffbe6cc3b12aab4d604e627829e93e9914 upstream.

The following call chain:
------------------------------------------------------------
nfs4_get_vfs_file
- nfsd_open
  - dentry_open
    - do_dentry_open
      - __get_file_write_access
        - get_write_access
          - return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
------------------------------------------------------------

can result in the following state:
------------------------------------------------------------
struct nfs4_file {
...
  fi_fds = {0xffff880c1fa65c80, 0xffffffffffffffe6, 0x0},
  fi_access = {{
      counter = 0x1
    }, {
      counter = 0x0
    }},
...
------------------------------------------------------------

1) First time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is
NULL, hence nfsd_open() is called where we get status set to an error
and fp->fi_fds[O_WRONLY] to -ETXTBSY. Thus we do not reach
nfs4_file_get_access() and fi_access[O_WRONLY] is not incremented.

2) Second time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is
NOT NULL (-ETXTBSY), so nfsd_open() is NOT called, but
nfs4_file_get_access() IS called and fi_access[O_WRONLY] is incremented.
Thus we leave a landmine in the form of the nfs4_file data structure in
an incorrect state.

3) Eventually, when __nfs4_file_put_access() is called it finds
fi_access[O_WRONLY] being non-zero, it decrements it and calls
nfs4_file_put_fd() which tries to fput -ETXTBSY.
------------------------------------------------------------
...
     [exception RIP: fput+0x9]
     RIP: ffffffff81177fa9  RSP: ffff88062e365c90  RFLAGS: 00010282
     RAX: ffff880c2b3d99cc  RBX: ffff880c2b3d9978  RCX: 0000000000000002
     RDX: dead000000100101  RSI: 0000000000000001  RDI: ffffffffffffffe6
     RBP: ffff88062e365c90   R8: ffff88041fe797d8   R9: ffff88062e365d58
     R10: 0000000000000008  R11: 0000000000000000  R12: 0000000000000001
     R13: 0000000000000007  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
  #9 [ffff88062e365c98] __nfs4_file_put_access at ffffffffa0562334 [nfsd]
 #10 [ffff88062e365cc8] nfs4_file_put_access at ffffffffa05623ab [nfsd]
 #11 [ffff88062e365ce8] free_generic_stateid at ffffffffa056634d [nfsd]
 #12 [ffff88062e365d18] release_open_stateid at ffffffffa0566e4b [nfsd]
 #13 [ffff88062e365d38] nfsd4_close at ffffffffa0567401 [nfsd]
 #14 [ffff88062e365d88] nfsd4_proc_compound at ffffffffa0557f28 [nfsd]
 #15 [ffff88062e365dd8] nfsd_dispatch at ffffffffa054543e [nfsd]
 #16 [ffff88062e365e18] svc_process_common at ffffffffa04ba5a4 [sunrpc]
 #17 [ffff88062e365e98] svc_process at ffffffffa04babe0 [sunrpc]
 #18 [ffff88062e365eb8] nfsd at ffffffffa0545b62 [nfsd]
 #19 [ffff88062e365ee8] kthread at ffffffff81090886
 #20 [ffff88062e365f48] kernel_thread at ffffffff8100c14a
------------------------------------------------------------

Signed-off-by: Harshula Jayasuriya <harshula@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
[xr: Backported to 3.4: adjust context]
Signed-off-by: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

md/raid10: fix "enough" function for detecting if array is failed.

commit 80b4812407c6b1f66a4f2430e69747a13f010839 upstream.

The 'enough' function is written to work with 'near' arrays only
in that is implicitly assumes that the offset from one 'group' of
devices to the next is the same as the number of copies.
In reality it is the number of 'near' copies.

So change it to make this number explicit.

This bug makes it possible to run arrays without enough drives
present, which is dangerous.
It is appropriate for an -stable kernel, but will almost certainly
need to be modified for some of them.

Reported-by: Jakub Husák <jakub@gooseman.cz>
Signed-off-by: NeilBrown <neilb@suse.de>
[bwh: Backported to 3.2: s/geo->/conf->/]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dm snapshot: add missing module aliases

commit 23cb21092eb9dcec9d3604b68d95192b79915890 upstream.

Add module aliases so that autoloading works correctly if the user
tries to activate "snapshot-origin" or "snapshot-merge" targets.

Reference: https://bugzilla.redhat.com/889973

Reported-by: Chao Yang <chyang@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dm bufio: avoid a possible __vmalloc deadlock

commit 502624bdad3dba45dfaacaf36b7d83e39e74b2d2 upstream.

This patch uses memalloc_noio_save to avoid a possible deadlock in
dm-bufio.  (it could happen only with large block size, at most
PAGE_SIZE << MAX_ORDER (typically 8MiB).

__vmalloc doesn't fully respect gfp flags. The specified gfp flags are
used for allocation of requested pages, structures vmap_area, vmap_block
and vm_struct and the radix tree nodes.

However, the kernel pagetables are allocated always with GFP_KERNEL.
Thus the allocation of pagetables can recurse back to the I/O layer and
cause a deadlock.

This patch uses the function memalloc_noio_save to set per-process
PF_MEMALLOC_NOIO flag and the function memalloc_noio_restore to restore
it. When this flag is set, all allocations in the process are done with
implied GFP_NOIO flag, thus the deadlock can't happen.

This should be backported to stable kernels, but they don't have the
PF_MEMALLOC_NOIO flag and memalloc_noio_save/memalloc_noio_restore
functions. So, PF_MEMALLOC should be set and restored instead.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
[bwh: Backported to 3.2 as recommended]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFSv4.1: Handle NFS4ERR_DELAY when resetting the NFSv4.1 session

commit c489ee290bdbbace6bb63ebe6ebd4dd605819495 upstream.

NFS4ERR_DELAY is a legal reply when we call DESTROY_SESSION. It
usually means that the server is busy handling an unfinished RPC
request. Just sleep for a second and then retry.
We also need to be able to handle the NFS4ERR_BACK_CHAN_BUSY return
value. If the NFS server has outstanding callbacks, we just want to
similarly sleep & retry.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFSv4.1: Don't decode skipped layoutgets

commit 085b7a45c63d3da5be155faab9249a5cab224561 upstream.

layoutget's prepare hook can call rpc_exit with status = NFS4_OK (0).
Because of this, nfs4_proc_layoutget can't depend on a 0 status to mean
that the RPC was successfully sent, received and parsed.

To fix this, use the result's len member to see if parsing took place.

This fixes the following OOPS -- calling xdr_init_decode() with a buffer length
0 doesn't set the stream's 'p' member and ends up using uninitialized memory
in filelayout_decode_layout.

BUG: unable to handle kernel paging request at 0000000000008050
IP: [<ffffffff81282e78>] memcpy+0x18/0x120
PGD 0
Oops: 0000 [#1] SMP
last sysfs file: /sys/devices/pci0000:00/0000:00:11.0/0000:02:01.0/irq
CPU 1
Modules linked in: nfs_layout_nfsv41_files nfs lockd fscache auth_rpcgss nfs_acl autofs4 sunrpc ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip_tables ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables ipv6 dm_mirror dm_region_hash dm_log dm_mod ppdev parport_pc parport snd_ens1371 snd_rawmidi snd_ac97_codec ac97_bus snd_seq snd_seq_device snd_pcm snd_timer snd soundcore snd_page_alloc e1000 microcode vmware_balloon i2c_piix4 i2c_core sg shpchp ext4 mbcache jbd2 sr_mod cdrom sd_mod crc_t10dif pata_acpi ata_generic ata_piix mptspi mptscsih mptbase scsi_transport_spi [last unloaded: speedstep_lib]

Pid: 1665, comm: flush-0:22 Not tainted 2.6.32-356-test-2 #2 VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform
RIP: 0010:[<ffffffff81282e78>]  [<ffffffff81282e78>] memcpy+0x18/0x120
RSP: 0018:ffff88003dfab588  EFLAGS: 00010206
RAX: ffff88003dc42000 RBX: ffff88003dfab610 RCX: 0000000000000009
RDX: 000000003f807ff0 RSI: 0000000000008050 RDI: ffff88003dc42000
RBP: ffff88003dfab5b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000080 R12: 0000000000000024
R13: ffff88003dc42000 R14: ffff88003f808030 R15: ffff88003dfab6a0
FS:  0000000000000000(0000) GS:ffff880003420000(0000) knlGS:0000000000000000
CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 0000000000008050 CR3: 000000003bc92000 CR4: 00000000001407e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process flush-0:22 (pid: 1665, threadinfo ffff88003dfaa000, task ffff880037f77540)
Stack:
ffffffffa0398ac1 ffff8800397c5940 ffff88003dfab610 ffff88003dfab6a0
<d> ffff88003dfab5d0 ffff88003dfab680 ffffffffa01c150b ffffea0000d82e70
<d> 000000508116713b 0000000000000000 0000000000000000 0000000000000000
Call Trace:
[<ffffffffa0398ac1>] ? xdr_inline_decode+0xb1/0x120 [sunrpc]
[<ffffffffa01c150b>] filelayout_decode_layout+0xeb/0x350 [nfs_layout_nfsv41_files]
[<ffffffffa01c17fc>] filelayout_alloc_lseg+0x8c/0x3c0 [nfs_layout_nfsv41_files]
[<ffffffff8150e6ce>] ? __wait_on_bit+0x7e/0x90

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFSv4.1: Fix a race in pNFS layoutcommit

commit a073dbff359f4741013ae4b8395f5364c5e00b48 upstream.

We need to clear the NFS_LSEG_LAYOUTCOMMIT bits atomically with the
NFS_INO_LAYOUTCOMMIT bit, otherwise we may end up with situations
where the two are out of sync.
The first half of the problem is to ensure that pnfs_layoutcommit_inode
clears the NFS_LSEG_LAYOUTCOMMIT bit through pnfs_list_write_lseg.
We still need to keep the reference to those segments until the RPC call
is finished, so in order to make it clear _where_ those references come
from, we add a helper pnfs_list_write_lseg_done() that cleans up after
pnfs_list_write_lseg.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Benny Halevy <bhalevy@tonian.com>
[bwh: Backported to 3.2: s/pnfs_put_lseg/put_lseg/]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFS: nfs_getaclargs.acl_len is a size_t

commit 56d08fef2369d5ca9ad2e1fc697f5379fd8af751 upstream.

Squelch compiler warnings:

fs/nfs/nfs4proc.c: In function ‘__nfs4_get_acl_uncached’:
fs/nfs/nfs4proc.c:3811:14: warning: comparison between signed and
unsigned integer expressions [-Wsign-compare]
fs/nfs/nfs4proc.c:3818:15: warning: comparison between signed and
unsigned integer expressions [-Wsign-compare]

Introduced by commit bf118a34 "NFSv4: include bitmap in nfsv4 get
acl data", Dec 7, 2011.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

nfsd: don't run get_file if nfs4_preprocess_stateid_op return error

commit b022032e195ffca83d7002d6b84297d796ed443b upstream.

we should return error status directly when nfs4_preprocess_stateid_op
return error.

Signed-off-by: fanchaoting <fanchaoting@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFSv4.1: integer overflow in decode_cb_sequence_args()

commit 0439f31c35d1da0b28988b308ea455e38e6a350d upstream.

This seems like it could overflow on 32 bits.  Use kmalloc_array() which
has overflow protection built in.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

nfsd4: fix xdr decoding of large non-write compounds

commit 365da4adebb1c012febf81019ad3dc5bb52e2a13 upstream.

This fixes a regression from 247500820ebd02ad87525db5d9b199e5b66f6636
"nfsd4: fix decoding of compounds across page boundaries".  The previous
code was correct: argp->pagelist is initialized in
nfs4svc_deocde_compoundargs to rqstp->rq_arg.pages, and is therefore a
pointer to the page *after* the page we are currently decoding.

The reason that patch nevertheless fixed a problem with decoding
compounds containing write was a bug in the write decoding introduced by
5a80a54d21c96590d013378d8c5f65f879451ab4 "nfsd4: reorganize write
decoding", after which write decoding no longer adhered to the rule that
argp->pagelist point to the next page.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
[bwh: Backported to 3.2: adjust context; there is only one instance to fix]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFSv4 wait on recovery for async session errors

commit 4a82fd7c4e78a1b7a224f9ae8bb7e1fd95f670e0 upstream.

When the state manager is processing the NFS4CLNT_DELEGRETURN flag, session
draining is off, but DELEGRETURN can still get a session error.
The async handler calls nfs4_schedule_session_recovery returns -EAGAIN, and
the DELEGRETURN done then restarts the RPC task in the prepare state.
With the state manager still processing the NFS4CLNT_DELEGRETURN flag with
session draining off, these DELEGRETURNs will cycle with errors filling up the
session slots.

This prevents OPEN reclaims (from nfs_delegation_claim_opens) required by the
NFS4CLNT_DELEGRETURN state manager processing from completing, hanging the
state manager in the __rpc_wait_for_completion_task in nfs4_run_open_task
as seen in this kernel thread dump:

kernel: 4.12.32.53-ma D 0000000000000000     0  3393      2 0x00000000
kernel: ffff88013995fb60 0000000000000046 ffff880138cc5400 ffff88013a9df140
kernel: ffff8800000265c0 ffffffff8116eef0 ffff88013fc10080 0000000300000001
kernel: ffff88013a4ad058 ffff88013995ffd8 000000000000fbc8 ffff88013a4ad058
kernel: Call Trace:
kernel: [<ffffffff8116eef0>] ? cache_alloc_refill+0x1c0/0x240
kernel: [<ffffffffa0358110>] ? rpc_wait_bit_killable+0x0/0xa0 [sunrpc]
kernel: [<ffffffffa0358152>] rpc_wait_bit_killable+0x42/0xa0 [sunrpc]
kernel: [<ffffffff8152914f>] __wait_on_bit+0x5f/0x90
kernel: [<ffffffffa0358110>] ? rpc_wait_bit_killable+0x0/0xa0 [sunrpc]
kernel: [<ffffffff815291f8>] out_of_line_wait_on_bit+0x78/0x90
kernel: [<ffffffff8109b520>] ? wake_bit_function+0x0/0x50
kernel: [<ffffffffa035810d>] __rpc_wait_for_completion_task+0x2d/0x30 [sunrpc]
kernel: [<ffffffffa040d44c>] nfs4_run_open_task+0x11c/0x160 [nfs]
kernel: [<ffffffffa04114e7>] nfs4_open_recover_helper+0x87/0x120 [nfs]
kernel: [<ffffffffa0411646>] nfs4_open_recover+0xc6/0x150 [nfs]
kernel: [<ffffffffa040cc6f>] ? nfs4_open_recoverdata_alloc+0x2f/0x60 [nfs]
kernel: [<ffffffffa0414e1a>] nfs4_open_delegation_recall+0x6a/0xa0 [nfs]
kernel: [<ffffffffa0424020>] nfs_end_delegation_return+0x120/0x2e0 [nfs]
kernel: [<ffffffff8109580f>] ? queue_work+0x1f/0x30
kernel: [<ffffffffa0424347>] nfs_client_return_marked_delegations+0xd7/0x110 [nfs]
kernel: [<ffffffffa04225d8>] nfs4_run_state_manager+0x548/0x620 [nfs]
kernel: [<ffffffffa0422090>] ? nfs4_run_state_manager+0x0/0x620 [nfs]
kernel: [<ffffffff8109b0f6>] kthread+0x96/0xa0
kernel: [<ffffffff8100c20a>] child_rip+0xa/0x20
kernel: [<ffffffff8109b060>] ? kthread+0x0/0xa0
kernel: [<ffffffff8100c200>] ? child_rip+0x0/0x20

The state manager can not therefore process the DELEGRETURN session errors.
Change the async handler to wait for recovery on session errors.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[bwh: Backported to 3.2:
 - Adjust context
 - There's no restart_call label]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

cifs: delay super block destruction until all cifsFileInfo objects are gone

commit 24261fc23db950951760d00c188ba63cc756b932 upstream.

cifsFileInfo objects hold references to dentries and it is possible that
these will still be around in workqueues when VFS decides to kill super
block during unmount.

This results in panics like this one:
BUG: Dentry ffff88001f5e76c0{i=66b4a,n=1M-2} still in use (1) [unmount of cifs cifs]
------------[ cut here ]------------
kernel BUG at fs/dcache.c:943!
[..]
Process umount (pid: 1781, threadinfo ffff88003d6e8000, task ffff880035eeaec0)
[..]
Call Trace:
 [<ffffffff811b44f3>] shrink_dcache_for_umount+0x33/0x60
 [<ffffffff8119f7fc>] generic_shutdown_super+0x2c/0xe0
 [<ffffffff8119f946>] kill_anon_super+0x16/0x30
 [<ffffffffa036623a>] cifs_kill_sb+0x1a/0x30 [cifs]
 [<ffffffff8119fcc7>] deactivate_locked_super+0x57/0x80
 [<ffffffff811a085e>] deactivate_super+0x4e/0x70
 [<ffffffff811bb417>] mntput_no_expire+0xd7/0x130
 [<ffffffff811bc30c>] sys_umount+0x9c/0x3c0
 [<ffffffff81657c19>] system_call_fastpath+0x16/0x1b

Fix this by making each cifsFileInfo object hold a reference to cifs
super block, which implicitly keeps VFS super block around as well.

Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reported-and-Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
[xr: Backported to 3.4: adjust context]
Signed-off-by: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

VFS: make vfs_fstat() use f[get|put]_light()

commit e994defb7b6813ba6fa7a2a36e86d2455ad1dc35 upstream.

Use the *_light() versions that properly avoid doing the file user count
updates when they are unnecessary.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[xr: Backported to 3.4: adjust function name]
Signed-off-by: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tracing: Keep overwrite in sync between regular and snapshot buffers

commit 80902822658aab18330569587cdb69ac1dfdcea8 upstream.

Changing the overwrite mode for the ring buffer via the trace
option only sets the normal buffer. But the snapshot buffer could
swap with it, and then the snapshot would be in non overwrite mode
and the normal buffer would be in overwrite mode, even though the
option flag states otherwise.

Keep the two buffers overwrite modes in sync.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

perf: Fix error return code

commit c481420248c6730246d2a1b1773d5d7007ae0835 upstream.

Fix to return -ENOMEM in the allocation error case instead of 0
(if pmu_bus_running == 1), as done elsewhere in this function.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: a.p.zijlstra@chello.nl
Cc: paulus@samba.org
Cc: acme@ghostprotocols.net
Link: http://lkml.kernel.org/r/CAPgLHd8j_fWcgqe%3DKLWjpBj%2B%3Do0Pw6Z-SEq%3DNTPU08c2w1tngQ@mail.gmail.com
[ Tweaked the error code setting placement and the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sched/debug: Fix sd->*_idx limit range avoiding overflow

commit fd9b86d37a600488dbd80fe60cca46b822bff1cd upstream.

Commit 201c373e8e ("sched/debug: Limit sd->*_idx range on
sysctl") was an incomplete bug fix.

This patch fixes sd->*_idx limit range to [0 ~ CPU_LOAD_IDX_MAX-1]
avoiding array overflow caused by setting sd->*_idx to CPU_LOAD_IDX_MAX
on sysctl.

Signed-off-by: Libin <huawei.libin@huawei.com>
Cc: <jiang.liu@huawei.com>
Cc: <guohanjun@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/51626610.2040607@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sched/debug: Limit sd->*_idx range on sysctl

commit 201c373e8e4823700d3160d5c28e1ab18fd1193e upstream.

Various sd->*_idx's are used for refering the rq's load average table
when selecting a cpu to run.  However they can be set to any number
with sysctl knobs so that it can crash the kernel if something bad is
given. Fix it by limiting them into the actual range.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1345104204-8317-1-git-send-email-namhyung@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ftrace: Check module functions being traced on reload

commit 8c4f3c3fa9681dc549cd35419b259496082fef8b upstream.

There's been a nasty bug that would show up and not give much info.
The bug displayed the following warning:

 WARNING: at kernel/trace/ftrace.c:1529 __ftrace_hash_rec_update+0x1e3/0x230()
 Pid: 20903, comm: bash Tainted: G           O 3.6.11+ #38405.trunk
 Call Trace:
  [<ffffffff8103e5ff>] warn_slowpath_common+0x7f/0xc0
  [<ffffffff8103e65a>] warn_slowpath_null+0x1a/0x20
  [<ffffffff810c2ee3>] __ftrace_hash_rec_update+0x1e3/0x230
  [<ffffffff810c4f28>] ftrace_hash_move+0x28/0x1d0
  [<ffffffff811401cc>] ? kfree+0x2c/0x110
  [<ffffffff810c68ee>] ftrace_regex_release+0x8e/0x150
  [<ffffffff81149f1e>] __fput+0xae/0x220
  [<ffffffff8114a09e>] ____fput+0xe/0x10
  [<ffffffff8105fa22>] task_work_run+0x72/0x90
  [<ffffffff810028ec>] do_notify_resume+0x6c/0xc0
  [<ffffffff8126596e>] ? trace_hardirqs_on_thunk+0x3a/0x3c
  [<ffffffff815c0f88>] int_signal+0x12/0x17
 ---[ end trace 793179526ee09b2c ]---

It was finally narrowed down to unloading a module that was being traced.

It was actually more than that. When functions are being traced, there's
a table of all functions that have a ref count of the number of active
tracers attached to that function. When a function trace callback is
registered to a function, the function's record ref count is incremented.
When it is unregistered, the function's record ref count is decremented.
If an inconsistency is detected (ref count goes below zero) the above
warning is shown and the function tracing is permanently disabled until
reboot.

The ftrace callback ops holds a hash of functions that it filters on
(and/or filters off). If the hash is empty, the default means to filter
all functions (for the filter_hash) or to disable no functions (for the
notrace_hash).

When a module is unloaded, it frees the function records that represent
the module functions. These records exist on their own pages, that is
function records for one module will not exist on the same page as
function records for other modules or even the core kernel.

Now when a module unloads, the records that represents its functions are
freed. When the module is loaded again, the records are recreated with
a default ref count of zero (unless there's a callback that traces all
functions, then they will also be traced, and the ref count will be
incremented).

The problem is that if an ftrace callback hash includes functions of the
module being unloaded, those hash entries will not be removed. If the
module is reloaded in the same location, the hash entries still point
to the functions of the module but the module's ref counts do not reflect
that.

With the help of Steve and Joern, we found a reproducer:

 Using uinput module and uinput_release function.

 cd /sys/kernel/debug/tracing
 modprobe uinput
 echo uinput_release > set_ftrace_filter
 echo function > current_tracer
 rmmod uinput
 modprobe uinput
 # check /proc/modules to see if loaded in same addr, otherwise try again
 echo nop > current_tracer

 [BOOM]

The above loads the uinput module, which creates a table of functions that
can be traced within the module.

We add uinput_release to the filter_hash to trace just that function.

Enable function tracincg, which increments the ref count of the record
associated to uinput_release.

Remove uinput, which frees the records including the one that represents
uinput_release.

Load the uinput module again (and make sure it's at the same address).
This recreates the function records all with a ref count of zero,
including uinput_release.

Disable function tracing, which will decrement the ref count for uinput_release
which is now zero because of the module removal and reload, and we have
a mismatch (below zero ref count).

The solution is to check all currently tracing ftrace callbacks to see if any
are tracing any of the module's functions when a module is loaded (it already does
that with callbacks that trace all functions). If a callback happens to have
a module function being traced, it increments that records ref count and starts
tracing that function.

There may be a strange side effect with this, where tracing module functions
on unload and then reloading a new module may have that new module's functions
being traced. This may be something that confuses the user, but it's not
a big deal. Another approach is to disable all callback hashes on module unload,
but this leaves some ftrace callbacks that may not be registered, but can
still have hashes tracing the module's function where ftrace doesn't know about
it. That situation can cause the same bug. This solution solves that case too.
Another benefit of this solution, is it is possible to trace a module's
function on unload and load.

Link: http://lkml.kernel.org/r/20130705142629.GA325@redhat.com
Reported-by: Jörn Engel <joern@logfs.org>
Reported-by: Dave Jones <davej@redhat.com>
Reported-by: Steve Hodgson <steve@purestorage.com>
Tested-by: Steve Hodgson <steve@purestorage.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

perf: Fix perf ring buffer memory ordering

commit bf378d341e4873ed928dc3c636252e6895a21f50 upstream.

The PPC64 people noticed a missing memory barrier and crufty old
comments in the perf ring buffer code. So update all the comments and
add the missing barrier.

When the architecture implements local_t using atomic_long_t there
will be double barriers issued; but short of introducing more
conditional barrier primitives this is the best we can do.

Reported-by: Victor Kaplansky <victork@il.ibm.com>
Tested-by: Victor Kaplansky <victork@il.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: michael@ellerman.id.au
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: anton@samba.org
Cc: benh@kernel.crashing.org
Link: http://lkml.kernel.org/r/20131025173749.GG19466@laptop.lan
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs: cachefiles: add support for large files in filesystem caching

commit 98c350cda2c14a343d34ea01a3d9c24fea5ec66d upstream.

Support the caching of large files.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=31182

Signed-off-by: Justin Lecher <jlec@gentoo.org>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.com>
Tested-by: Suresh Jayaraman <sjayaraman@suse.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2:
 - Adjust context
 - dentry_open() takes dentry and vfsmount pointers, not a path pointer]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ecryptfs: Fix memory leakage in keystore.c

commit 3edc8376c06133e3386265a824869cad03a4efd4 upstream.

In 'decrypt_pki_encrypted_session_key' function:

Initializes 'payload' pointer and releases it on exit.

Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

CIFS: Fix error handling in cifs_push_mandatory_locks

commit e2f2886a824ff0a56da1eaa13019fde86aa89fa6 upstream.

Signed-off-by: Pavel Shilovsky <pshilovsky@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

setfacl removes part of ACL when setting POSIX ACLs to Samba

commit b1d93356427be6f050dc55c86eb019d173700af6 upstream.

setfacl over cifs mounts can remove the default ACL when setting the
(non-default part of) the ACL and vice versa (we were leaving at 0
rather than setting to -1 the count field for the unaffected
half of the ACL.  For example notice the setfacl removed
the default ACL in this sequence:

steven@steven-GA-970A-DS3:~/cifs-2.6$ getfacl /mnt/test-dir ; setfacl
-m default:user:test:rwx,user:test:rwx /mnt/test-dir
getfacl: Removing leading '/' from absolute path names
user::rwx
group::r-x
other::r-x
default:user::rwx
default:user:test:rwx
default:group::r-x
default:mask::rwx
default:other::r-x

steven@steven-GA-970A-DS3:~/cifs-2.6$ getfacl /mnt/test-dir
getfacl: Removing leading '/' from absolute path names
user::rwx
user:test:rwx
group::r-x
mask::rwx
other::r-x

Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Jeremy Allison <jra@samba.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

crypto: caam - add allocation failure handling in SPRINTFCAT macro

commit 27c5fb7a84242b66bf1e0b2fe6bf40d19bcc5c04 upstream.

GFP_ATOMIC memory allocation could fail.
In this case, avoid NULL pointer dereference and notify user.

Cc: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Horia Geanta <horia.geanta@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

i2c: designware: Mask all interrupts during i2c controller enable

commit 47bb27e78867997040a228328f2a631c3c7f2c82 upstream.

There have been "i2c_designware 80860F41:00: controller timed out" errors
on a number of Baytrail platforms. The issue is caused by incorrect value in
Interrupt Mask Register (DW_IC_INTR_MASK)  when i2c core is being enabled.
This causes call to __i2c_dw_enable() to immediately start the transfer which
leads to timeout. There are 3 failure modes observed:

1. Failure in S0 to S3 resume path

The default value after reset for DW_IC_INTR_MASK is 0x8ff. When we start
the first transaction after resuming from system sleep, TX_EMPTY interrupt
is already unmasked because of the hardware default.

2. Failure in normal operational path

This failure happens rarely and is hard to reproduce. Debug trace showed that
DW_IC_INTR_MASK had value of 0x254 when failure occurred, which meant
TX_EMPTY was unmasked.

3. Failure in S3 to S0 suspend path

This failure also happens rarely and is hard to reproduce. Adding debug trace
that read DW_IC_INTR_MASK made this failure not reproducible. But from ISR
call trace we could conclude TX_EMPTY was unmasked when problem occurred.

The patch masks all interrupts before the controller is enabled to resolve the
faulty DW_IC_INTR_MASK conditions.

Signed-off-by: Wenkai Du <wenkai.du@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[wsa: improved the comment and removed typo in commit msg]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ACPI / blacklist: Add dmi_enable_osi_linux quirk for Asus EEE PC 1015PX

commit f6e6e1b9fee88c90586787b71dc49bb3ce62bb89 upstream.

Without this this EEE PC exports a non working WMI interface, with this it
exports a working "good old" eeepc_laptop interface, fixing brightness control
not working as well as rfkill being stuck in a permanent wireless blocked
state.

This is not an ideal way to fix this, but various attempts to fix this
otherwise have failed, see:

References: https://bugzilla.redhat.com/show_bug.cgi?id=1067181
Reported-and-tested-by: lou.cardone@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

PCI: shpchp: Check bridge's secondary (not primary) bus speed

commit 93fa9d32670f5592c8e56abc9928fc194e1e72fc upstream.

When a new device is added below a hotplug bridge, the bridge's secondary
bus speed and the device's bus speed must match.  The shpchp driver
previously checked the bridge's *primary* bus speed, not the secondary bus
speed.

This caused hot-add errors like:

  shpchp 0000:00:03.0: Speed of bus ff and adapter 0 mismatch

Check the secondary bus speed instead.

[bhelgaas: changelog]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=75251
Fixes: 3749c51ac6c1 ("PCI: Make current and maximum bus speeds part of the PCI core")
Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86-64, modify_ldt: Make support for 16-bit segments a runtime option

commit fa81511bb0bbb2b1aace3695ce869da9762624ff upstream.

Checkin:

b3b42ac2cbae x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels

disabled 16-bit segments on 64-bit kernels due to an information
leak.  However, it does seem that people are genuinely using Wine to
run old 16-bit Windows programs on Linux.

A proper fix for this ("espfix64") is coming in the upcoming merge
window, but as a temporary fix, create a sysctl to allow the
administrator to re-enable support for 16-bit segments.

It adds a "/proc/sys/abi/ldt16" sysctl that defaults to zero (off). If
you hit this issue and care about your old Windows program more than
you care about a kernel stack address information leak, you can do

   echo 1 > /proc/sys/abi/ldt16

as root (add it to your startup scripts), and you should be ok.

The sysctl table is only added if you have COMPAT support enabled on
x86-64, but I assume anybody who runs old windows binaries very much
does that ;)

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/CA%2B55aFw9BPoD10U1LfHbOMpHWZkvJTkMcfCs9s3urPr1YyWBxw@mail.gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ASoC: wm8962: Update register CLASS_D_CONTROL_1 to be non-volatile

commit 44330ab516c15dda8a1e660eeaf0003f84e43e3f upstream.

The register CLASS_D_CONTROL_1 is marked as volatile because it contains
a bit, DAC_MUTE, which is also mirrored in the ADC_DAC_CONTROL_1
register. This causes problems for the "Speaker Switch" control, which
will report an error if the CODEC is suspended because it relies on a
volatile register.

To resolve this issue mark CLASS_D_CONTROL_1 as non-volatile and
manually keep the register cache in sync by updating both bits when
changing the mute status.

Reported-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

percpu: make pcpu_alloc_chunk() use pcpu_mem_free() instead of kfree()

commit 5a838c3b60e3a36ade764cf7751b8f17d7c9c2da upstream.

pcpu_chunk_struct_size = sizeof(struct pcpu_chunk) +
BITS_TO_LONGS(pcpu_unit_pages) * sizeof(unsigned long)

It hardly could be ever bigger than PAGE_SIZE even for large-scale machine,
but for consistency with its couterpart pcpu_mem_zalloc(),
use pcpu_mem_free() instead.

Commit b4916cb17c26 ("percpu: make pcpu_free_chunk() use
pcpu_mem_free() instead of kfree()") addressed this problem, but
missed this one.

tj: commit message updated

Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: 099a19d91ca4 ("percpu: allow limited allocation before slab is online)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

nfsd4: remove lockowner when removing lock stateid

commit a1b8ff4c97b4375d21b6d6c45d75877303f61b3b upstream.

The nfsv4 state code has always assumed a one-to-one correspondance
between lock stateid's and lockowners even if it appears not to in some
places.

We may actually change that, but for now when FREE_STATEID releases a
lock stateid it also needs to release the parent lockowner.

Symptoms were a subsequent LOCK crashing in find_lockowner_str when it
calls same_lockowner_ino on a lockowner that unexpectedly has an empty
so_stateids list.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

nfsd4: warn on finding lockowner without stateid's

commit 27b11428b7de097c42f205beabb1764f4365443b upstream.

The current code assumes a one-to-one lockowner<->lock stateid
correspondance.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFSD: Call ->set_acl with a NULL ACL structure if no entries

commit aa07c713ecfc0522916f3cd57ac628ea6127c0ec upstream.

After setting ACL for directory, I got two problems that caused
by the cached zero-length default posix acl.

This patch make sure nfsd4_set_nfs4_acl calls ->set_acl
with a NULL ACL structure if there are no entries.

Thanks for Christoph Hellwig's advice.

First problem:
............ hang ...........

Second problem:
[ 1610.167668] ------------[ cut here ]------------
[ 1610.168320] kernel BUG at /root/nfs/linux/fs/nfsd/nfs4acl.c:239!
[ 1610.168320] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
[ 1610.168320] Modules linked in: nfsv4(OE) nfs(OE) nfsd(OE)
rpcsec_gss_krb5 fscache ip6t_rpfilter ip6t_REJECT cfg80211 xt_conntrack
rfkill ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables
ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6
ip6table_mangle ip6table_security ip6table_raw ip6table_filter
ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4
nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw
auth_rpcgss nfs_acl snd_intel8x0 ppdev lockd snd_ac97_codec ac97_bus
snd_pcm snd_timer e1000 pcspkr parport_pc snd parport serio_raw joydev
i2c_piix4 sunrpc(OE) microcode soundcore i2c_core ata_generic pata_acpi
[last unloaded: nfsd]
[ 1610.168320] CPU: 0 PID: 27397 Comm: nfsd Tainted: G           OE
3.15.0-rc1+ #15
[ 1610.168320] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS
VirtualBox 12/01/2006
[ 1610.168320] task: ffff88005ab653d0 ti: ffff88005a944000 task.ti:
ffff88005a944000
[ 1610.168320] RIP: 0010:[<ffffffffa034d5ed>]  [<ffffffffa034d5ed>]
_posix_to_nfsv4_one+0x3cd/0x3d0 [nfsd]
[ 1610.168320] RSP: 0018:ffff88005a945b00  EFLAGS: 00010293
[ 1610.168320] RAX: 0000000000000001 RBX: ffff88006700bac0 RCX:
0000000000000000
[ 1610.168320] RDX: 0000000000000000 RSI: ffff880067c83f00 RDI:
ffff880068233300
[ 1610.168320] RBP: ffff88005a945b48 R08: ffffffff81c64830 R09:
0000000000000000
[ 1610.168320] R10: ffff88004ea85be0 R11: 000000000000f475 R12:
ffff880068233300
[ 1610.168320] R13: 0000000000000003 R14: 0000000000000002 R15:
ffff880068233300
[ 1610.168320] FS:  0000000000000000(0000) GS:ffff880077800000(0000)
knlGS:0000000000000000
[ 1610.168320] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 1610.168320] CR2: 00007f5bcbd3b0b9 CR3: 0000000001c0f000 CR4:
00000000000006f0
[ 1610.168320] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[ 1610.168320] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[ 1610.168320] Stack:
[ 1610.168320]  ffffffff00000000 0000000b67c83500 000000076700bac0
0000000000000000
[ 1610.168320]  ffff88006700bac0 ffff880068233300 ffff88005a945c08
0000000000000002
[ 1610.168320]  0000000000000000 ffff88005a945b88 ffffffffa034e2d5
000000065a945b68
[ 1610.168320] Call Trace:
[ 1610.168320]  [<ffffffffa034e2d5>] nfsd4_get_nfs4_acl+0x95/0x150 [nfsd]
[ 1610.168320]  [<ffffffffa03400d6>] nfsd4_encode_fattr+0x646/0x1e70 [nfsd]
[ 1610.168320]  [<ffffffff816a6e6e>] ? kmemleak_alloc+0x4e/0xb0
[ 1610.168320]  [<ffffffffa0327962>] ?
nfsd_setuser_and_check_port+0x52/0x80 [nfsd]
[ 1610.168320]  [<ffffffff812cd4bb>] ? selinux_cred_prepare+0x1b/0x30
[ 1610.168320]  [<ffffffffa0341caa>] nfsd4_encode_getattr+0x5a/0x60 [nfsd]
[ 1610.168320]  [<ffffffffa0341e07>] nfsd4_encode_operation+0x67/0x110
[nfsd]
[ 1610.168320]  [<ffffffffa033844d>] nfsd4_proc_compound+0x21d/0x810 [nfsd]
[ 1610.168320]  [<ffffffffa0324d9b>] nfsd_dispatch+0xbb/0x200 [nfsd]
[ 1610.168320]  [<ffffffffa00850cd>] svc_process_common+0x46d/0x6d0 [sunrpc]
[ 1610.168320]  [<ffffffffa0085433>] svc_process+0x103/0x170 [sunrpc]
[ 1610.168320]  [<ffffffffa032472f>] nfsd+0xbf/0x130 [nfsd]
[ 1610.168320]  [<ffffffffa0324670>] ? nfsd_destroy+0x80/0x80 [nfsd]
[ 1610.168320]  [<ffffffff810a5202>] kthread+0xd2/0xf0
[ 1610.168320]  [<ffffffff810a5130>] ? insert_kthread_work+0x40/0x40
[ 1610.168320]  [<ffffffff816c1ebc>] ret_from_fork+0x7c/0xb0
[ 1610.168320]  [<ffffffff810a5130>] ? insert_kthread_work+0x40/0x40
[ 1610.168320] Code: 78 02 e9 e7 fc ff ff 31 c0 31 d2 31 c9 66 89 45 ce
41 8b 04 24 66 89 55 d0 66 89 4d d2 48 8d 04 80 49 8d 5c 84 04 e9 37 fd
ff ff <0f> 0b 90 0f 1f 44 00 00 55 8b 56 08 c7 07 00 00 00 00 8b 46 0c
[ 1610.168320] RIP  [<ffffffffa034d5ed>] _posix_to_nfsv4_one+0x3cd/0x3d0
[nfsd]
[ 1610.168320]  RSP <ffff88005a945b00>
[ 1610.257313] ---[ end trace 838254e3e352285b ]---

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

trace: module: Maintain a valid user count

commit 098507ae3ec2331476fb52e85d4040c1cc6d0ef4 upstream.

The replacement of the 'count' variable by two variables 'incs' and
'decs' to resolve some race conditions during module unloading was done
in parallel with some cleanup in the trace subsystem, and was integrated
as a merge.

Unfortunately, the formula for this replacement was wrong in the tracing
code, and the refcount in the traces was not usable as a result.

Use 'count = incs - decs' to compute the user count.

Link: http://lkml.kernel.org/p/1393924179-9147-1-git-send-email-romain.izard.pro@gmail.com
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Fixes: c1ab9cab7509 "merge conflict resolution"
Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

media: media-device: fix infoleak in ioctl media_enum_entities()

commit e6a623460e5fc960ac3ee9f946d3106233fd28d8 upstream.

This fixes CVE-2014-1739.

Signed-off-by: Salva Peiró <speiro@ai2.upv.es>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

crypto: crypto_wq - Fix late crypto work queue initialization

commit 130fa5bc81b44b6cc1fbdea3abf6db0da22964e0 upstream.

The crypto algorithm modules utilizing the crypto daemon could
be used early when the system start up.  Using module_init
does not guarantee that the daemon's work queue is initialized
when the cypto alorithm depending on crypto_wq starts.  It is necessary
to initialize the crypto work queue earlier at the subsystem
init time to make sure that it is initialized
when used.

Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation: Update stable address in Chinese and Japanese translations

commit 98b0f811aade1b7c6e7806c86aa0befd5919d65f upstream.

The English and Korean translations were updated, the Chinese and Japanese
weren't.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drm/nouveau/acpi: allow non-optimus setups to load vbios from acpi

commit a3d0b1218d351c6e6f3cea36abe22236a08cb246 upstream.

There appear to be a crop of new hardware where the vbios is not
available from PROM/PRAMIN, but there is a valid _ROM method in ACPI.
The data read from PCIROM almost invariably contains invalid
instructions (still has the x86 opcodes), which makes this a low-risk
way to try to obtain a valid vbios image.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76475
Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

rtl8192cu: Fix unbalanced irq enable in error path of rtl92cu_hw_init()

commit 3234f5b06fc3094176a86772cc64baf3decc98fc upstream.

Fixes: a53268be0cb9 ('rtlwifi: rtl8192cu: Fix too long disable of IRQs')
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: 8012/1: kdump: Avoid overflow when converting pfn to physaddr

commit 8fad87bca7ac9737e413ba5f1656f1114a8c314d upstream.

When we configure CONFIG_ARM_LPAE=y, pfn << PAGE_SHIFT will
overflow if pfn >= 0x100000 in copy_oldmem_page.
So use __pfn_to_phys for converting.

Signed-off-by: Liu Hua <sdu.liu@huawei.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

posix_acl: handle NULL ACL in posix_acl_equiv_mode

commit 50c6e282bdf5e8dabf8d7cf7b162545a55645fd9 upstream.

Various filesystems don't bother checking for a NULL ACL in
posix_acl_equiv_mode, and thus can dereference a NULL pointer when it
gets passed one. This usually happens from the NFS server, as the ACL tools
never pass a NULL ACL, but instead of one representing the mode bits.

Instead of adding boilerplat to all filesystems put this check into one place,
which will allow us to remove the check from other filesystems as well later
on.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Ben Greear <greearb@candelatech.com>
Reported-by: Marco Munderloh <munderl@tnt.uni-hannover.de>,
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

rt2x00: fix beaconing on USB

commit 8834d3608cc516f13e2e510f4057c263f3d2ce42 upstream.

When disable beaconing we clear register with beacon and newer set it
back, what make we stop send beacons infinitely.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: Nokia 5300 should be treated as unusual dev

commit 6ed07d45d09bc2aa60e27b845543db9972e22a38 upstream.

Signed-off-by: Daniele Forsi <dforsi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: Nokia 305 should be treated as unusual dev

commit f0ef5d41792a46a1085dead9dfb0bdb2c574638e upstream.

Signed-off-by: Victor A. Santos <victoraur.santos@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: storage: shuttle_usbat: fix discs being detected twice

commit df602c2d2358f02c6e49cffc5b49b9daa16db033 upstream.

Even if the USB-to-ATAPI converter supported multiple LUNs, this
driver would always detect the same physical device or media because
it doesn't use srb->device->lun in any way.
Tested with an Hewlett-Packard CD-Writer Plus 8200e.

Signed-off-by: Daniele Forsi <dforsi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: at91-udc: fix irq and iomem resource retrieval

commit 886c7c426d465732ec9d1b2bbdda5642fc2e7e05 upstream.

When using dt resources retrieval (interrupts and reg properties) there is
no predefined order for these resources in the platform dev resource
table. Also don't expect the number of resource to be always 2.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
Acked-by: Boris BREZILLON <b.brezillon@overkiz.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drm/radeon: fix ATPX detection on non-VGA GPUs

commit e9a4099a59cc598a44006059dd775c25e422b772 upstream.

Some newer PX laptops have the pci device class
set to DISPLAY_OTHER rather than DISPLAY_VGA.  This
properly detects ATPX on those laptops.

Based on a patch from: Pali Rohár <pali.rohar@gmail.com>

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: airlied@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

md: avoid possible spinning md thread at shutdown.

commit 0f62fb220aa4ebabe8547d3a9ce4a16d3c045f21 upstream.

If an md array with externally managed metadata (e.g. DDF or IMSM)
is in use, then we should not set safemode==2 at shutdown because:

1/ this is ineffective: user-space need to be involved in any 'safemode' handling,
2/ The safemode management code doesn't cope with safemode==2 on external metadata
   and md_check_recover enters an infinite loop.

Even at shutdown, an infinite-looping process can be problematic, so this
could cause shutdown to hang.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

hrtimer: Set expiry time before switch_hrtimer_base()

commit 84ea7fe37908254c3bd90910921f6e1045c1747a upstream.

switch_hrtimer_base() calls hrtimer_check_target() which ensures that
we do not migrate a timer to a remote cpu if the timer expires before
the current programmed expiry time on that remote cpu.

But __hrtimer_start_range_ns() calls switch_hrtimer_base() before the
new expiry time is set. So the sanity check in hrtimer_check_target()
is operating on stale or even uninitialized data.

Update expiry time before calling switch_hrtimer_base().

[ tglx: Rewrote changelog once again ]

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: linaro-networking@linaro.org
Cc: fweisbec@gmail.com
Cc: arvind.chauhan@arm.com
Link: http://lkml.kernel.org/r/81999e148745fc51bbcd0615823fbab9b2e87e23.1399882253.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

hrtimer: Prevent remote enqueue of leftmost timers

commit 012a45e3f4af68e86d85cce060c6c2fed56498b2 upstream.

If a cpu is idle and starts an hrtimer which is not pinned on that
same cpu, the nohz code might target the timer to a different cpu.

In the case that we switch the cpu base of the timer we already have a
sanity check in place, which determines whether the timer is earlier
than the current leftmost timer on the target cpu. In that case we
enqueue the timer on the current cpu because we cannot reprogram the
clock event device on the target.

If the timers base is already the target CPU we do not have this
sanity check in place so we enqueue the timer as the leftmost timer in
the target cpus rb tree, but we cannot reprogram the clock event
device on the target cpu. So the timer expires late and subsequently
prevents the reprogramming of the target cpu clock event device until
the previously programmed event fires or a timer with an earlier
expiry time gets enqueued on the target cpu itself.

Add the same target check as we have for the switch base case and
start the timer on the current cpu if it would become the leftmost
timer on the target.

[ tglx: Rewrote subject and changelog ]

Signed-off-by: Leon Ma <xindong.ma@intel.com>
Link: http://lkml.kernel.org/r/1398847391-5994-1-git-send-email-xindong.ma@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

hrtimer: Prevent all reprogramming if hang detected

commit 6c6c0d5a1c949d2e084706f9e5fb1fccc175b265 upstream.

If the last hrtimer interrupt detected a hang it sets hang_detected=1
and programs the clock event device with a delay to let the system
make progress.

If hang_detected == 1, we prevent reprogramming of the clock event
device in hrtimer_reprogram() but not in hrtimer_force_reprogram().

This can lead to the following situation:

hrtimer_interrupt()
   hang_detected = 1;
   program ce device to Xms from now (hang delay)

We have two timers pending:
   T1 expires 50ms from now
   T2 expires 5s from now

Now T1 gets canceled, which causes hrtimer_force_reprogram() to be
invoked, which in turn programs the clock event device to T2 (5
seconds from now).

Any hrtimer_start after that will not reprogram the hardware due to
hang_detected still being set. So we effectivly block all timers until
the T2 event fires and cleans up the hang situation.

Add a check for hang_detected to hrtimer_force_reprogram() which
prevents the reprogramming of the hang delay in the hardware
timer. The subsequent hrtimer_interrupt will resolve all outstanding
issues.

[ tglx: Rewrote subject and changelog and fixed up the comment in
   hrtimer_force_reprogram() ]

Signed-off-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Link: http://lkml.kernel.org/r/53602DC6.2060101@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivercore: deferral race condition fix

commit 58b116bce13612e5aa6fcd49ecbd4cf8bb59e835 upstream.

When the kernel is built with CONFIG_PREEMPT it is possible to reach a state
when all modules loaded but some driver still stuck in the deferred list
and there is a need for external event to kick the deferred queue to probe
these drivers.

The issue has been observed on embedded systems with CONFIG_PREEMPT enabled,
audio support built as modules and using nfsroot for root filesystem.

The following log fragment shows such sequence when all audio modules
were loaded but the sound card is not present since the machine driver has
failed to probe due to missing dependency during it's probe.
The board is am335x-evmsk (McASP<->tlv320aic3106 codec) with davinci-evm
machine driver:

...
[   12.615118] davinci-mcasp 4803c000.mcasp: davinci_mcasp_probe: ENTER
[   12.719969] davinci_evm sound.3: davinci_evm_probe: ENTER
[   12.725753] davinci_evm sound.3: davinci_evm_probe: snd_soc_register_card
[   12.753846] davinci-mcasp 4803c000.mcasp: davinci_mcasp_probe: snd_soc_register_component
[   12.922051] davinci-mcasp 4803c000.mcasp: davinci_mcasp_probe: snd_soc_register_component DONE
[   12.950839] davinci_evm sound.3: ASoC: platform (null) not registered
[   12.957898] davinci_evm sound.3: davinci_evm_probe: snd_soc_register_card DONE (-517)
[   13.099026] davinci-mcasp 4803c000.mcasp: Kicking the deferred list
[   13.177838] davinci-mcasp 4803c000.mcasp: really_probe: probe_count = 2
[   13.194130] davinci_evm sound.3: snd_soc_register_card failed (-517)
[   13.346755] davinci_mcasp_driver_init: LEAVE
[   13.377446] platform sound.3: Driver davinci_evm requests probe deferral
[   13.592527] platform sound.3: really_probe: probe_count = 0

In the log the machine driver enters it's probe at 12.719969 (this point it
has been removed from the deferred lists). McASP driver already executing
it's probing (since 12.615118).
The machine driver tries to construct the sound card (12.950839) but did
not found one of the components so it fails. After this McASP driver
registers all the ASoC components (the machine driver still in it's probe
function after it failed to construct the card) and the deferred work is
prepared at 13.099026 (note that this time the machine driver is not in the
lists so it is not going to be handled when the work is executing).
Lastly the machine driver exit from it's probe and the core places it to
the deferred list but there will be no other driver going to load and the
deferred queue is not going to be kicked again - till we have external event
like connecting USB stick, etc.

The proposed solution is to try the deferred queue once more when the last
driver is asking for deferring and we had drivers loaded while this last
driver was probing.

This way we can avoid drivers stuck in the deferred queue.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

hwmon: (emc1403) Support full range of known chip revision numbers

commit 3a18e1398fc2dc9c32bbdc50664da3a77959a8d1 upstream.

The datasheet for EMC1413/EMC1414, which is fully compatible to
EMC1403/1404 and uses the same chip identification, references revision
numbers 0x01, 0x03, and 0x04. Accept the full range of revision numbers
from 0x01 to 0x04 to make sure none are missed.

Signed-off-by: Josef Gajdusek <atx@atx.name>
[Guenter Roeck: Updated headline and description]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

hwmon: (emc1403) fix inverted store_hyst()

commit 17c048fc4bd95efea208a1920f169547d8588f1f upstream.

Attempts to set the hysteresis value to a temperature below the target
limit fails with "write error: Numerical result out of range" due to
an inverted comparison.

Signed-off-by: Josef Gajdusek <atx@atx.name>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
[Guenter Roeck: Updated headline and description]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

hwpoison, hugetlb: lock_page/unlock_page does not match for handling a free hugepage

commit b985194c8c0a130ed155b71662e39f7eaea4876f upstream.

For handling a free hugepage in memory failure, the race will happen if
another thread hwpoisoned this hugepage concurrently.  So we need to
check PageHWPoison instead of !PageHWPoison.

If hwpoison_filter(p) returns true or a race happens, then we need to
unlock_page(hpage).

Signed-off-by: Chen Yucong <slaoub@gmail.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Tested-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86, mm, hugetlb: Add missing TLB page invalidation for hugetlb_cow()

commit 9844f5462392b53824e8b86726e7c33b5ecbb676 upstream.

The invalidation is required in order to maintain proper semantics
under CoW conditions. In scenarios where a process clones several
threads, a thread operating on a core whose DTLB entry for a
particular hugepage has not been invalidated, will be reading from
the hugepage that belongs to the forked child process, even after
hugetlb_cow().

The thread will not see the updated page as long as the stale DTLB
entry remains cached, the thread attempts to write into the page,
the child process exits, or the thread gets migrated to a different
processor.

Signed-off-by: Anthony Iliopoulos <anthony.iliopoulos@huawei.com>
Link: http://lkml.kernel.org/r/20140514092948.GA17391@server-36.huawei.corp
Suggested-by: Shay Goikhman <shay.goikhman@huawei.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ipmi: Reset the KCS timeout when starting error recovery

commit eb6d78ec213e6938559b801421d64714dafcf4b2 upstream.

The OBF timer in KCS was not reset in one situation when error recovery
was started, resulting in an immediate timeout.

Reported-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ipmi: Fix a race restarting the timer

commit 48e8ac2979920ffa39117e2d725afa3a749bfe8d upstream.

With recent changes it is possible for the timer handler to detect an
idle interface and not start the timer, but the thread to start an
operation at the same time.  The thread will not start the timer in that
instance, resulting in the timer not running.

Instead, move all timer operations under the lock and start the timer in
the thread if it detect non-idle and the timer is not already running.
Moving under locks allows the last timeout to be set in both the thread
and the timer.  'Timer is not running' means that the timer is not
pending and smi_timeout() is not running.  So we need a flag to detect
this correctly.

Also fix a few other timeout bugs: setting the last timeout when the
interrupt has to be disabled and the timer started, and setting the last
timeout in check_start_timer_thread possibly racing with the timer

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

timer: Prevent overflow in apply_slack

commit 98a01e779f3c66b0b11cd7e64d531c0e41c95762 upstream.

On architectures with sizeof(int) < sizeof (long), the
computation of mask inside apply_slack() can be undefined if the
computed bit is > 32.

E.g. with: expires = 0xffffe6f5 and slack = 25, we get:

expires_limit = 0x20000000e
bit = 33
mask = (1 << 33) - 1  /* undefined */

On x86, mask becomes 1 and and the slack is not applied properly.
On s390, mask is -1, expires is set to 0 and the timer fires immediately.

Use 1UL << bit to solve that issue.

Suggested-by: Deborah Townsend <dstownse@us.ibm.com>
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Link: http://lkml.kernel.org/r/20140418152310.GA13654@midget.suse.cz
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mm: make fixup_user_fault() check the vma access rights too

commit 1b17844b29ae042576bea588164f2f1e9590a8bc upstream.

fixup_user_fault() is used by the futex code when the direct user access
fails, and the futex code wants it to either map in the page in a usable
form or return an error.  It relied on handle_mm_fault() to map the
page, and correctly checked the error return from that, but while that
does map the page, it doesn't actually guarantee that the page will be
mapped with sufficient permissions to be then accessed.

So do the appropriate tests of the vma access rights by hand.

[ Side note: arguably handle_mm_fault() could just do that itself, but
  we have traditionally done it in the caller, because some callers -
  notably get_user_pages() - have been able to access pages even when
  they are mapped with PROT_NONE.  Maybe we should re-visit that design
  decision, but in the meantime this is the minimal patch. ]

Found by Dave Jones running his trinity tool.

Reported-by: Dave Jones <davej@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pata_at91: fix ata_host_activate() failure handling

commit 27aa64b9d1bd0d23fd692c91763a48309b694311 upstream.

Add missing clk_put() call to ata_host_activate() failure path.

Sergei says,

  "Hm, I have once fixed that (see that *if* (!ret)) but looks like a
   later commit 477c87e90853d136b188c50c0e4a93d01cad872e (ARM:
   at91/pata: use gpio_is_valid to check the gpio) broke it again. :-(
   Would be good if the changelog did mention that..."

Cc: Andrew Victor <linux@maxim.org.za>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ftrace/module: Hardcode ftrace_module_init() call into load_module()

commit a949ae560a511fe4e3adf48fa44fefded93e5c2b upstream.

A race exists between module loading and enabling of function tracer.

CPU 1 CPU 2
----- -----
  load_module()
   module->state = MODULE_STATE_COMING

register_ftrace_function()
 mutex_lock(&ftrace_lock);
 ftrace_startup()
  update_ftrace_function();
   ftrace_arch_code_modify_prepare()
    set_all_module_text_rw();
   <enables-ftrace>
    ftrace_arch_code_modify_post_process()
     set_all_module_text_ro();

[ here all module text is set to RO,
  including the module that is
  loading!! ]

   blocking_notifier_call_chain(MODULE_STATE_COMING);
    ftrace_init_module()

     [ tries to modify code, but it's RO, and fails!
       ftrace_bug() is called]

When this race happens, ftrace_bug() will produces a nasty warning and
all of the function tracing features will be disabled until reboot.

The simple solution is to treate module load the same way the core
kernel is treated at boot. To hardcode the ftrace function modification
of converting calls to mcount into nops. This is done in init/main.c
there's no reason it could not be done in load_module(). This gives
a better control of the changes and doesn't tie the state of the
module to its notifiers as much. Ftrace is special, it needs to be
treated as such.

The reason this would work, is that the ftrace_module_init() would be
called while the module is in MODULE_STATE_UNFORMED, which is ignored
by the set_all_module_text_ro() call.

Link: http://lkml.kernel.org/r/1395637826-3312-1-git-send-email-indou.takao@jp.fujitsu.com
Reported-by: Takao Indoh <indou.takao@jp.fujitsu.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

futex: Prevent attaching to kernel threads

commit f0d71b3dcb8332f7971b5f2363632573e6d9486a upstream.

We happily allow userspace to declare a random kernel thread to be the
owner of a user space PI futex.

Found while analysing the fallout of Dave Jones syscall fuzzer.

We also should validate the thread group for private futexes and find
some fast way to validate whether the "alleged" owner has RW access on
the file which backs the SHM, but that's a separate issue.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dave Jones <davej@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <darren@dvhart.com>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Carlos ODonell <carlos@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20140512201701.194824402@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

futex: Add another early deadlock detection check

commit 866293ee54227584ffcb4a42f69c1f365974ba7f upstream.

Dave Jones trinity syscall fuzzer exposed an issue in the deadlock
detection code of rtmutex:
  http://lkml.kernel.org/r/20140429151655.GA14277@redhat.com

That underlying issue has been fixed with a patch to the rtmutex code,
but the futex code must not call into rtmutex in that case because
    - it can detect that issue early
    - it avoids a different and more complex fixup for backing out

If the user space variable got manipulated to 0x80000000 which means
no lock holder, but the waiters bit set and an active pi_state in the
kernel is found we can figure out the recursive locking issue by
looking at the pi_state owner. If that is the current task, then we
can safely return -EDEADLK.

The check should have been added in commit 59fa62451 (futex: Handle
futex_pi OWNER_DIED take over correctly) already, but I did not see
the above issue caused by user space manipulation back then.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dave Jones <davej@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <darren@dvhart.com>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Carlos ODonell <carlos@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20140512201701.097349971@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net-gro: reset skb->truesize in napi_reuse_skb()

[ Upstream commit e33d0ba8047b049c9262fdb1fcafb93cb52ceceb ]

Recycling skb always had been very tough...

This time it appears GRO layer can accumulate skb->truesize
adjustments made by drivers when they attach a fragment to skb.

skb_gro_receive() can only subtract from skb->truesize the used part
of a fragment.

I spotted this problem seeing TcpExtPruneCalled and
TcpExtTCPRcvCollapsed that were unexpected with a recent kernel, where
TCP receive window should be sized properly to accept traffic coming
from a driver not overshooting skb->truesize.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

skb: Add inline helper for getting the skb end offset from head

[ Upstream commit ec47ea82477404631d49b8e568c71826c9b663ac ]

With the recent changes for how we compute the skb truesize it occurs to me
we are probably going to have a lot of calls to skb_end_pointer -
skb->head.  Instead of running all over the place doing that it would make
more sense to just make it a separate inline skb_end_offset(skb) that way
we can return the correct value without having gcc having to do all the
optimization to cancel out skb->head - skb->head.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ipv4: initialise the itag variable in __mkroute_input

[ Upstream commit fbdc0ad095c0a299e9abf5d8ac8f58374951149a ]

the value of itag is a random value from stack, and may not be initiated by
fib_validate_source, which called fib_combine_itag if CONFIG_IP_ROUTE_CLASSID
is not set

This will make the cached dst uncertainty

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

act_mirred: do not drop packets when fails to mirror it

[ Upstream commit 16c0b164bd24d44db137693a36b428ba28970c62 ]

We drop packet unconditionally when we fail to mirror it. This is not intended
in some cases. Consdier for kvm guest, we may mirror the traffic of the bridge
to a tap device used by a VM. When kernel fails to mirror the packet in
conditions such as when qemu crashes or stop polling the tap, it's hard for the
management software to detect such condition and clean the the mirroring
before. This would lead all packets to the bridge to be dropped and break the
netowrk of other virtual machines.

To solve the issue, the patch does not drop packets when kernel fails to mirror
it, and only drop the redirected packets.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ipv4: fib_semantics: increment fib_info_cnt after fib_info allocation

[ Upstream commit aeefa1ecfc799b0ea2c4979617f14cecd5cccbfd ]

Increment fib_info_cnt in fib_create_info() right after successfuly
alllocating fib_info structure, overwise fib_metrics allocation failure
leads to fib_info_cnt incorrectly decremented in free_fib_info(), called
on error path from fib_create_info().

Signed-off-by: Sergey Popovich <popovich_sergei@mail.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net: ipv4: ip_forward: fix inverted local_df test

[ Upstream commit ca6c5d4ad216d5942ae544bbf02503041bd802aa ]

local_df means 'ignore DF bit if set', so if its set we're
allowed to perform ip fragmentation.

This wasn't noticed earlier because the output path also drops such skbs
(and emits needed icmp error) and because netfilter ip defrag did not
set local_df until couple of days ago.

Only difference is that DF-packets-larger-than MTU now discarded
earlier (f.e. we avoid pointless netfilter postrouting trip).

While at it, drop the repeated test ip_exceeds_mtu, checking it once
is enough...

Fixes: fe6cc55f3a9 ("net: ip, ipv6: handle gso skbs in forwarding path")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tcp_cubic: fix the range of delayed_ack

[ Upstream commit 0cda345d1b2201dd15591b163e3c92bad5191745 ]

commit b9f47a3aaeab (tcp_cubic: limit delayed_ack ratio to prevent
divide error) try to prevent divide error, but there is still a little
chance that delayed_ack can reach zero. In case the param cnt get
negative value, then ratio+cnt would overflow and may happen to be zero.
As a result, min(ratio, ACK_RATIO_LIMIT) will calculate to be zero.

In some old kernels, such as 2.6.32, there is a bug that would
pass negative param, which then ultimately leads to this divide error.

commit 5b35e1e6e9c (tcp: fix tcp_trim_head() to adjust segment count
with skb MSS) fixed the negative param issue. However,
it's safe that we fix the range of delayed_ack as well,
to make sure we do not hit a divide by zero.

CC: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Liu Yu <allanyuliu@tencent.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>