ANDROID: sdcardfs: Switch strcasecmp for internal call

This moves our uses of strcasecmp over to an internal call so we can
easily change implementations later if we so desire. Additionally,
we leverage qstr's where appropriate to save time on comparisons.

Change-Id: I32fdc4fd0cd3b7b735dcfd82f60a2516fd8272a5
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: switch to full_name_hash and qstr

Use the kernel's string hash function instead of rolling
our own. Additionally, save a bit of calculation by using
the qstr struct in place of strings.

Change-Id: I0bbeb5ec2a9233f40135ad632e6f22c30ffa95c1
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Add GID Derivation to sdcardfs

This changes sdcardfs to modify the user and group in the
underlying filesystem depending on its usage. Ownership is
set by Android user, and package, as well as if the file is
under obb or cache. Other files can be labeled by extension.
Those values are set via the configfs interace.

To add an entry,
mkdir -p [configfs root]/sdcardfs/extensions/[gid]/[ext]

Bug: 34262585
Change-Id: I4e030ce84f094a678376349b1a96923e5076a0f4
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Remove redundant operation

We call get_derived_permission_new unconditionally, so we don't need
to call update_derived_permission_lock, which does the same thing.

Change-Id: I0748100828c6af806da807241a33bf42be614935
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: add support for user permission isolation

This allows you to hide the existence of a package from
a user by adding them to an exclude list. If a user
creates that package's folder and is on the exclude list,
they will not see that package's id.

Bug: 34542611
Change-Id: I9eb82e0bf2457d7eb81ee56153b9c7d2f6646323
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Refactor configfs interface

This refactors the configfs code to be more easily extended.
It will allow additional files to be added easily.

Bug: 34542611
Bug: 34262585
Change-Id: I73c9b0ae5ca7eb27f4ebef3e6807f088b512d539
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Allow non-owners to touch

This modifies the permission checks in setattr to
allow for non-owners to modify the timestamp of
files to things other than the current time.
This still requires write access, as enforced by
the permission call, but relaxes the requirement
that the caller must be the owner, allowing those
with group permissions to change it as well.

Bug: 11118565
Change-Id: Ied31f0cce2797675c7ef179eeb4e088185adcbad
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: binder: fix format specifier for type binder_size_t

Fix following warning on 32bit ARCH build:

  CC      drivers/android/binder.o
drivers/android/binder.c: In function ‘binder_transaction’:
./include/linux/kern_levels.h:4:18: warning: format ‘%lld’ expects argument of type ‘long long int’,
but argument 4 has type ‘binder_size_t {aka unsigned int}’ [-Wformat=]
drivers/android/binder.c:2047:3: note: in expansion of macro ‘binder_user_error’
   binder_user_error("%d:%d got transaction with unaligned buffers size, %lld\n",
   ^

Change-Id: I943d0d4d54f7f2a019900cc18e55bed661bec5a5
Fixes: Change-Id: I02417f28cff14688f2e1d6fcb959438fd96566cc
       (android: binder: support for scatter-gather.")
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>

ANDROID: fs: Export vfs_rmdir2

allmodconfig builds fail with

ERROR: "vfs_rmdir2" undefined!

Export the missing function.

Change-Id: I983d327e59fd34e0484f3c54d925e97d3905c19c
Fixes: f9cb61dcb00c ("ANDROID: sdcardfs: User new permission2 functions")
Signed-off-by: Guenter Roeck <groeck@chromium.org>

ANDROID: fs: Export free_fs_struct and set_fs_pwd

allmodconfig builds fail with:

ERROR: "free_fs_struct" undefined!
ERROR: "set_fs_pwd" undefined!

Export the missing symbols.

Change-Id: I4877ead19d7e7f0c93d4c4cad5681364284323aa
Fixes: 0ec03f845799 ("ANDROID: sdcardfs: override umask on mkdir and create")
Signed-off-by: Guenter Roeck <groeck@chromium.org>

ANDROID: mnt: remount should propagate to slaves of slaves

propagate_remount was not accounting for the slave mounts
of other slave mounts, leading to some namespaces not
recieving the remount information.

bug:33731928
Change-Id: Idc9e8c2ed126a4143229fc23f10a959c2d0a3854
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Switch ->d_inode to d_inode()

Change-Id: I12375cc2d6e82fb8adf0319be971f335f8d7a312
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Fix locking issue with permision fix up

Don't use lookup_one_len so we can grab the spinlock that
protects d_subdirs.

Bug: 30954918
Change-Id: I0c6a393252db7beb467e0d563739a3a14e1b5115
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Change magic value

Sdcardfs uses the same magic value as wrapfs.
This should not be the case. As it is entirely
in memory, the value can be changed without any
loss of compatibility.

Change-Id: I24200b805d5e6d32702638be99e47d50d7f2f746
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Use per mount permissions

This switches sdcardfs over to using permission2.
Instead of mounting several sdcardfs instances onto
the same underlaying directory, you bind mount a
single mount several times, and remount with the
options you want. These are stored in the private
mount data, allowing you to maintain the same tree,
but have different permissions for different mount
points.

Warning functions have been added for permission,
as it should never be called, and the correct
behavior is unclear.

Change-Id: I841b1d70ec60cf2b866fa48edeb74a0b0f8334f5
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Add gid and mask to private mount data

Adds support for mount2, remount2, and the functions
to allocate/clone/copy the private data

The next patch will switch over to actually using it.

Change-Id: I8a43da26021d33401f655f0b2784ead161c575e3
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: User new permission2 functions

Change-Id: Ic7e0fb8fdcebb31e657b079fe02ac834c4a50db9
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: vfs: Add setattr2 for filesystems with per mount permissions

This allows filesystems to use their mount private data to
influence the permssions they use in setattr2. It has
been separated into a new call to avoid disrupting current
setattr users.

Change-Id: I19959038309284448f1b7f232d579674ef546385
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: vfs: Add permission2 for filesystems with per mount permissions

This allows filesystems to use their mount private data to
influence the permssions they return in permission2. It has
been separated into a new call to avoid disrupting current
permission users.

Change-Id: I9d416e3b8b6eca84ef3e336bd2af89ddd51df6ca
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: vfs: Allow filesystems to access their private mount data

Now we pass the vfsmount when mounting and remounting.
This allows the filesystem to actually set up the mount
specific data, although we can't quite do anything with
it yet. show_options is expanded to include data that
lives with the mount.

To avoid changing existing filesystems, these have
been added as new vfs functions.

Change-Id: If80670bfad9f287abb8ac22457e1b034c9697097
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: mnt: Add filesystem private data to mount points

This starts to add private data associated directly
to mount points. The intent is to give filesystems
a sense of where they have come from, as a means of
letting a filesystem take different actions based on
this information.

Change-Id: Ie769d7b3bb2f5972afe05c1bf16cf88c91647ab2
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Move directory unlock before touch

This removes a deadlock under low memory conditions.
filp_open can call lookup_slow, which will attempt to
lock the parent.

Change-Id: I940643d0793f5051d1e79a56f4da2fa8ca3d8ff7
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: fix external storage exporting incorrect uid

Symptom: App cannot write into per-app folder
Root Cause: sdcardfs exports incorrect uid
Solution: fix uid
Project: All
Note:
Test done by RD: passed

Change-Id: Iff64f6f40ba4c679f07f4426d3db6e6d0db7e3ca

ANDROID: sdcardfs: Added top to sdcardfs_inode_info

Adding packages to the package list and moving files
takes a large amount of locks, and is currently a
heavy operation. This adds a 'top' field to the
inode_info, which points to the inode for the top
most directory whose owner you would like to match.

On permission checks and get_attr, we look up the
owner based on the information at top. When we change
a package mapping, we need only modify the information
in the corresponding top inode_info's. When renaming,
we must ensure top is set correctly in all children.
This happens when an app specific folder gets moved
outside of the folder for that app.

Change-Id: Ib749c60b568e9a45a46f8ceed985c1338246ec6c
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Switch package list to RCU

Switched the package id hashmap to use RCU.

Change-Id: I9fdcab279009005bf28536247d11e13babab0b93
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Fix locking for permission fix up

Iterating over d_subdirs requires taking d_lock.
Removed several unneeded locks.

Change-Id: I5b1588e54c7e6ee19b756d6705171c7f829e2650
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: Check for other cases on path lookup

This fixes a bug where the first lookup of a
file or folder created under a different view
would not be case insensitive. It will now
search through for a case insensitive match
if the initial lookup fails.

Bug:28024488
Change-Id: I4ff9ce297b9f2f9864b47540e740fd491c545229
Signed-off-by: Daniel Rosenberg <drosen@google.com>

ANDROID: sdcardfs: override umask on mkdir and create

The mode on files created on the lower fs should
not be affected by the umask of the calling
task's fs_struct. Instead, we create a copy
and modify it as needed. This also lets us avoid
the string shenanigans around .nomedia files.

Bug: 27992761
Change-Id: Ia3a6e56c24c6e19b3b01c1827e46403bb71c2f4c
Signed-off-by: Daniel Rosenberg <drosen@google.com>

Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android

 Merge tag 'v4.4.44' into linux-linaro-lsk-v4.4

 This is the 4.4.44 stable release

Linux 4.4.44

pinctrl: sh-pfc: Do not unconditionally support PIN_CONFIG_BIAS_DISABLE

commit 5d7400c4acbf7fe633a976a89ee845f7333de3e4 upstream.

Always stating PIN_CONFIG_BIAS_DISABLE is supported gives untrue output
when examining /sys/kernel/debug/pinctrl/e6060000.pfc/pinconf-pins if
the operation get_bias() is implemented but the pin is not handled by
the get_bias() implementation. In that case the output will state that
"input bias disabled" indicating that this pin has bias control
support.

Make support for PIN_CONFIG_BIAS_DISABLE depend on that the pin either
supports SH_PFC_PIN_CFG_PULL_UP or SH_PFC_PIN_CFG_PULL_DOWN. This also
solves the issue where SoC specific implementations print error messages
if their particular implementation of {set,get}_bias() is called with a
pin it does not know about.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

powerpc/ibmebus: Fix device reference leaks in sysfs interface

commit fe0f3168169f7c34c29b0cf0c489f126a7f29643 upstream.

Make sure to drop any reference taken by bus_find_device() in the sysfs
callbacks that are used to create and destroy devices based on
device-tree entries.

Fixes: 6bccf755ff53 ("[POWERPC] ibmebus: dynamic addition/removal of adapters, some code cleanup")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

powerpc/ibmebus: Fix further device reference leaks

commit 815a7141c4d1b11610dccb7fcbb38633759824f2 upstream.

Make sure to drop any reference taken by bus_find_device() when creating
devices during init and driver registration.

Fixes: 55347cc9962f ("[POWERPC] ibmebus: Add device creation and bus probing based on of_device")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

bus: vexpress-config: fix device reference leak

commit c090959b9dd8c87703e275079aa4b4a824ba3f8e upstream.

Make sure to drop the reference to the parent device taken by
class_find_device() after populating the bus.

Fixes: 3b9334ac835b ("mfd: vexpress: Convert custom func API to regmap")
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

blk-mq: Always schedule hctx->next_cpu

commit c02ebfdddbafa9a6a0f52fbd715e6bfa229af9d3 upstream.

Commit 0e87e58bf60e ("blk-mq: improve warning for running a queue on the
wrong CPU") attempts to avoid triggering the WARN_ON in
__blk_mq_run_hw_queue when the expected CPU is dead.  Problem is, in the
last batch execution before round robin, blk_mq_hctx_next_cpu can
schedule a dead CPU and also update next_cpu to the next alive CPU in
the mask, which will trigger the WARN_ON despite the previous
workaround.

The following patch fixes this scenario by always scheduling the value
in hctx->next_cpu.  This changes the moment when we round-robin the CPU
running the hctx, but it really doesn't matter, since it still executes
BLK_MQ_CPU_WORK_BATCH times in a row before switching to another CPU.

Fixes: 0e87e58bf60e ("blk-mq: improve warning for running a queue on the wrong CPU")
Signed-off-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ACPI / APEI: Fix NMI notification handling

commit a545715d2dae8d071c5b06af947b07ffa846b288 upstream.

When removing and adding cpu 0 on a system with GHES NMI the following stack
trace is seen when re-adding the cpu:

WARNING: CPU: 0 PID: 0 at arch/x86/kernel/apic/apic.c:1349 setup_local_APIC+
Modules linked in: nfsv3 rpcsec_gss_krb5 nfsv4 nfs fscache coretemp intel_ra
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.0-rc6+ #2
Call Trace:
 dump_stack+0x63/0x8e
 __warn+0xd1/0xf0
 warn_slowpath_null+0x1d/0x20
 setup_local_APIC+0x275/0x370
 apic_ap_setup+0xe/0x20
 start_secondary+0x48/0x180
 set_init_arg+0x55/0x55
 early_idt_handler_array+0x120/0x120
 x86_64_start_reservations+0x2a/0x2c
 x86_64_start_kernel+0x13d/0x14c

During the cpu bringup, wakeup_cpu_via_init_nmi() is called and issues an
NMI on CPU 0.  The GHES NMI handler, ghes_notify_nmi() runs the
ghes_proc_irq_work work queue which ends up setting IRQ_WORK_VECTOR
(0xf6).  The "faulty" IR line set at arch/x86/kernel/apic/apic.c:1349 is  also
0xf6 (specifically APIC IRR for irqs 255 to 224 is 0x400000) which confirms
that something has set the IRQ_WORK_VECTOR line prior to the APIC being
initialized.

Commit 2383844d4850 ("GHES: Elliminate double-loop in the NMI handler")
incorrectly modified the behavior such that the handler returns
NMI_HANDLED only if an error was processed, and incorrectly runs the ghes
work queue for every NMI.

This patch modifies the ghes_proc_irq_work() to run as it did prior to
2383844d4850 ("GHES: Elliminate double-loop in the NMI handler") by
properly returning NMI_HANDLED and only calling the work queue if
NMI_HANDLED has been set.

Fixes: 2383844d4850 (GHES: Elliminate double-loop in the NMI handler)
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

block: cfq_cpd_alloc() should use @gfp

commit ebc4ff661fbe76781c6b16dfb7b754a5d5073f8e upstream.

cfq_cpd_alloc() which is the cpd_alloc_fn implementation for cfq was
incorrectly hard coding GFP_KERNEL instead of using the mask specified
through the @gfp parameter.  This currently doesn't cause any actual
issues because all current callers specify GFP_KERNEL.  Fix it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: e4a9bde9589f ("blkcg: replace blkcg_policy->cpd_size with ->cpd_alloc/free_fn() methods")
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

cpufreq: powernv: Disable preemption while checking CPU throttling state

commit 8a10c06a20ec8097a68fd7a4a1c0e285095b4d2f upstream.

With preemption turned on we can read incorrect throttling state
while being switched to CPU on a different chip.

 BUG: using smp_processor_id() in preemptible [00000000] code: cat/7343
 caller is .powernv_cpufreq_throttle_check+0x2c/0x710
 CPU: 13 PID: 7343 Comm: cat Not tainted 4.8.0-rc5-dirty #1
 Call Trace:
 [c0000007d25b75b0] [c000000000971378] .dump_stack+0xe4/0x150 (unreliable)
 [c0000007d25b7640] [c0000000005162e4] .check_preemption_disabled+0x134/0x150
 [c0000007d25b76e0] [c0000000007b63ac] .powernv_cpufreq_throttle_check+0x2c/0x710
 [c0000007d25b7790] [c0000000007b6d18] .powernv_cpufreq_target_index+0x288/0x360
 [c0000007d25b7870] [c0000000007acee4] .__cpufreq_driver_target+0x394/0x8c0
 [c0000007d25b7920] [c0000000007b22ac] .cpufreq_set+0x7c/0xd0
 [c0000007d25b79b0] [c0000000007adf50] .store_scaling_setspeed+0x80/0xc0
 [c0000007d25b7a40] [c0000000007ae270] .store+0xa0/0x100
 [c0000007d25b7ae0] [c0000000003566e8] .sysfs_kf_write+0x88/0xb0
 [c0000007d25b7b70] [c0000000003553b8] .kernfs_fop_write+0x178/0x260
 [c0000007d25b7c10] [c0000000002ac3cc] .__vfs_write+0x3c/0x1c0
 [c0000007d25b7cf0] [c0000000002ad584] .vfs_write+0xc4/0x230
 [c0000007d25b7d90] [c0000000002aeef8] .SyS_write+0x58/0x100
 [c0000007d25b7e30] [c00000000000bfec] system_call+0x38/0xfc

Fixes: 09a972d16209 (cpufreq: powernv: Report cpu frequency throttling)
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFSv4.1: nfs4_fl_prepare_ds must be careful about reporting success.

commit cfd278c280f997cf2fe4662e0acab0fe465f637b upstream.

Various places assume that if nfs4_fl_prepare_ds() turns a non-NULL 'ds',
then ds->ds_clp will also be non-NULL.

This is not necessasrily true in the case when the process received a fatal signal
while nfs4_pnfs_ds_connect is waiting in nfs4_wait_ds_connect().
In that case ->ds_clp may not be set, and the devid may not recently have been marked
unavailable.

So add a test for ds_clp == NULL and return NULL in that case.

Fixes: c23266d532b4 ("NFS4.1 Fix data server connection race")
Signed-off-by: NeilBrown <neilb@suse.com>
Acked-by: Olga Kornievskaia <aglo@umich.edu>
Acked-by: Adamson, Andy <William.Adamson@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFS: Fix a performance regression in readdir

commit 79f687a3de9e3ba2518b4ea33f38ca6cbe9133eb upstream.

Ben Coddington reports that commit 311324ad1713, by adding the function
nfs_dir_mapping_need_revalidate() that checks page cache validity on
each call to nfs_readdir() causes a performance regression when
the directory is being modified.

If the directory is changing while we're iterating through the directory,
POSIX does not require us to invalidate the page cache unless the user
calls rewinddir(). However, we still do want to ensure that we use
readdirplus in order to avoid a load of stat() calls when the user
is doing an 'ls -l' workload.

The fix should be to invalidate the page cache immediately when we're
setting the NFS_INO_ADVISE_RDPLUS bit.

Reported-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: 311324ad1713 ("NFS: Be more aggressive in using readdirplus...")
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pNFS: Fix race in pnfs_wait_on_layoutreturn

commit ee284e35d8c71bf5d4d807eaff6f67a17134b359 upstream.

We must put the task to sleep while holding the inode->i_lock in order
to ensure atomicity with the test for NFS_LAYOUT_RETURN.

Fixes: 500d701f336b ("NFS41: make close wait for layoutreturn")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pinctrl: meson: fix gpio request disabling other modes

commit f24d311f92b516a8aadef5056424ccabb4068e7b upstream.

The pinctrl_gpio_request is called with the "full" gpio number, already
containing the base, then meson_pmx_request_gpio is then called with the
final pin number.
Remove the base addition when calling meson_pmx_disable_other_groups.

Fixes: 6ac730951104 ("pinctrl: add driver for Amlogic Meson SoCs")
CC: Beniamino Galvani <b.galvani@gmail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Kevin Hilman <khilman@baylibre.com>
Acked-by: Beniamino Galvani <b.galvani@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

btrfs: fix error handling when run_delayed_extent_op fails

commit aa7c8da35d1905d80e840d075f07d26ec90144b5 upstream.

In __btrfs_run_delayed_refs, the error path when run_delayed_extent_op
fails sets locked_ref->processing = 0 but doesn't re-increment
delayed_refs->num_heads_ready.  As a result, we end up triggering
the WARN_ON in btrfs_select_ref_head.

Fixes: d7df2c796d7 (Btrfs: attach delayed ref updates to delayed ref heads)
Reported-by: Jon Nelson <jnelson-suse@jamponi.net>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

btrfs: fix locking when we put back a delayed ref that's too new

commit d0280996437081dd12ed1e982ac8aeaa62835ec4 upstream.

In __btrfs_run_delayed_refs, when we put back a delayed ref that's too
new, we have already dropped the lock on locked_ref when we set
->processing = 0.

This patch keeps the lock to cover that assignment.

Fixes: d7df2c796d7 (Btrfs: attach delayed ref updates to delayed ref heads)
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/cpu: Fix bootup crashes by sanitizing the argument of the 'clearcpuid=' command-line option

commit dd853fd216d1485ed3045ff772079cc8689a9a4a upstream.

A negative number can be specified in the cmdline which will be used as
setup_clear_cpu_cap() argument. With that we can clear/set some bit in
memory predceeding boot_cpu_data/cpu_caps_cleared which may cause kernel
to misbehave. This patch adds lower bound check to setup_disablecpuid().

Boris Petkov reproduced a crash:

  [    1.234575] BUG: unable to handle kernel paging request at ffffffff858bd540
  [    1.236535] IP: memcpy_erms+0x6/0x10

Signed-off-by: Lukasz Odzioba <lukasz.odzioba@intel.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: andi.kleen@intel.com
Cc: bp@alien8.de
Cc: dave.hansen@linux.intel.com
Cc: luto@kernel.org
Cc: slaoub@gmail.com
Fixes: ac72e7888a61 ("x86: add generic clearcpuid=... option")
Link: http://lkml.kernel.org/r/1482933340-11857-1-git-send-email-lukasz.odzioba@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ch341: fix modem-control and B0 handling

commit 030ee7ae52a46a2be52ccc8242c4a330aba8d38e upstream.

The modem-control signals are managed by the tty-layer during open and
should not be asserted prematurely when set_termios is called from
driver open.

Also make sure that the signals are asserted only when changing speed
from B0.

Fixes: 664d5df92e88 ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ch341: fix resume after reset

commit ce5e292828117d1b71cbd3edf9e9137cf31acd30 upstream.

Fix reset-resume handling which failed to resubmit the read and
interrupt URBs, thereby leaving a port that was open before suspend in a
broken state until closed and reopened.

Fixes: 1ded7ea47b88 ("USB: ch341 serial: fix port number changed after
resume")
Fixes: 2bfd1c96a9fb ("USB: serial: ch341: remove reset_resume callback")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drm/radeon: drop verde dpm quirks

commit 8a08403bcb39f5d0e733bcf59a8a74f16b538f6e upstream.

fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=98897
https://bugs.launchpad.net/bugs/1651981

Acked-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Adrian Fiergolski <A.Fiergolski@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sysctl: Drop reference added by grab_header in proc_sys_readdir

commit 93362fa47fe98b62e4a34ab408c4a418432e7939 upstream.

Fixes CVE-2016-9191, proc_sys_readdir doesn't drop reference
added by grab_header when return from !dir_emit_dots path.
It can cause any path called unregister_sysctl_table will
wait forever.

The calltrace of CVE-2016-9191:

[ 5535.960522] Call Trace:
[ 5535.963265]  [<ffffffff817cdaaf>] schedule+0x3f/0xa0
[ 5535.968817]  [<ffffffff817d33fb>] schedule_timeout+0x3db/0x6f0
[ 5535.975346]  [<ffffffff817cf055>] ? wait_for_completion+0x45/0x130
[ 5535.982256]  [<ffffffff817cf0d3>] wait_for_completion+0xc3/0x130
[ 5535.988972]  [<ffffffff810d1fd0>] ? wake_up_q+0x80/0x80
[ 5535.994804]  [<ffffffff8130de64>] drop_sysctl_table+0xc4/0xe0
[ 5536.001227]  [<ffffffff8130de17>] drop_sysctl_table+0x77/0xe0
[ 5536.007648]  [<ffffffff8130decd>] unregister_sysctl_table+0x4d/0xa0
[ 5536.014654]  [<ffffffff8130deff>] unregister_sysctl_table+0x7f/0xa0
[ 5536.021657]  [<ffffffff810f57f5>] unregister_sched_domain_sysctl+0x15/0x40
[ 5536.029344]  [<ffffffff810d7704>] partition_sched_domains+0x44/0x450
[ 5536.036447]  [<ffffffff817d0761>] ? __mutex_unlock_slowpath+0x111/0x1f0
[ 5536.043844]  [<ffffffff81167684>] rebuild_sched_domains_locked+0x64/0xb0
[ 5536.051336]  [<ffffffff8116789d>] update_flag+0x11d/0x210
[ 5536.057373]  [<ffffffff817cf61f>] ? mutex_lock_nested+0x2df/0x450
[ 5536.064186]  [<ffffffff81167acb>] ? cpuset_css_offline+0x1b/0x60
[ 5536.070899]  [<ffffffff810fce3d>] ? trace_hardirqs_on+0xd/0x10
[ 5536.077420]  [<ffffffff817cf61f>] ? mutex_lock_nested+0x2df/0x450
[ 5536.084234]  [<ffffffff8115a9f5>] ? css_killed_work_fn+0x25/0x220
[ 5536.091049]  [<ffffffff81167ae5>] cpuset_css_offline+0x35/0x60
[ 5536.097571]  [<ffffffff8115aa2c>] css_killed_work_fn+0x5c/0x220
[ 5536.104207]  [<ffffffff810bc83f>] process_one_work+0x1df/0x710
[ 5536.110736]  [<ffffffff810bc7c0>] ? process_one_work+0x160/0x710
[ 5536.117461]  [<ffffffff810bce9b>] worker_thread+0x12b/0x4a0
[ 5536.123697]  [<ffffffff810bcd70>] ? process_one_work+0x710/0x710
[ 5536.130426]  [<ffffffff810c3f7e>] kthread+0xfe/0x120
[ 5536.135991]  [<ffffffff817d4baf>] ret_from_fork+0x1f/0x40
[ 5536.142041]  [<ffffffff810c3e80>] ? kthread_create_on_node+0x230/0x230

One cgroup maintainer mentioned that "cgroup is trying to offline
a cpuset css, which takes place under cgroup_mutex.  The offlining
ends up trying to drain active usages of a sysctl table which apprently
is not happening."
The real reason is that proc_sys_readdir doesn't drop reference added
by grab_header when return from !dir_emit_dots path. So this cpuset
offline path will wait here forever.

See here for details: http://www.openwall.com/lists/oss-security/2016/11/04/13

Fixes: f0c3b5093add ("[readdir] convert procfs")
Reported-by: CAI Qian <caiqian@redhat.com>
Tested-by: Yang Shukui <yangshukui@huawei.com>
Signed-off-by: Zhou Chengming <zhouchengming1@huawei.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sysrq: attach sysrq handler correctly for 32-bit kernel

commit 802c03881f29844af0252b6e22be5d2f65f93fd0 upstream.

The sysrq input handler should be attached to the input device which has
a left alt key.

On 32-bit kernels, some input devices which has a left alt key cannot
attach sysrq handler.  Because the keybit bitmap in struct input_device_id
for sysrq is not correctly initialized.  KEY_LEFTALT is 56 which is
greater than BITS_PER_LONG on 32-bit kernels.

I found this problem when using a matrix keypad device which defines
a KEY_LEFTALT (56) but doesn't have a KEY_O (24 == 56%32).

Cc: Jiri Slaby <jslaby@suse.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty/serial: atmel_serial: BUG: stop DMA from transmitting in stop_tx

commit 89d8232411a85b9a6b12fd5da4d07d8a138a8e0c upstream.

If we don't disable the transmitter in atmel_stop_tx, the DMA buffer
continues to send data until it is emptied.
This cause problems with the flow control (CTS is asserted and data are
still sent).

So, disabling the transmitter in atmel_stop_tx is a sane thing to do.

Tested on at91sam9g35-cm(DMA)
Tested for regressions on sama5d2-xplained(Fifo) and at91sam9g20ek(PDC)

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mnt: Protect the mountpoint hashtable with mount_lock

commit 3895dbf8985f656675b5bde610723a29cbce3fa7 upstream.

Protecting the mountpoint hashtable with namespace_sem was sufficient
until a call to umount_mnt was added to mntput_no_expire.  At which
point it became possible for multiple calls of put_mountpoint on
the same hash chain to happen on the same time.

Kristen Johansen <kjlx@templeofstupid.com> reported:
> This can cause a panic when simultaneous callers of put_mountpoint
> attempt to free the same mountpoint.  This occurs because some callers
> hold the mount_hash_lock, while others hold the namespace lock.  Some
> even hold both.
>
> In this submitter's case, the panic manifested itself as a GP fault in
> put_mountpoint() when it called hlist_del() and attempted to dereference
> a m_hash.pprev that had been poisioned by another thread.

Al Viro observed that the simple fix is to switch from using the namespace_sem
to the mount_lock to protect the mountpoint hash table.

I have taken Al's suggested patch moved put_mountpoint in pivot_root
(instead of taking mount_lock an additional time), and have replaced
new_mountpoint with get_mountpoint a function that does the hash table
lookup and addition under the mount_lock.   The introduction of get_mounptoint
ensures that only the mount_lock is needed to manipulate the mountpoint
hashtable.

d_set_mounted is modified to only set DCACHE_MOUNTED if it is not
already set.  This allows get_mountpoint to use the setting of
DCACHE_MOUNTED to ensure adding a struct mountpoint for a dentry
happens exactly once.

Fixes: ce07d891a089 ("mnt: Honor MNT_LOCKED when detaching mounts")
Reported-by: Krister Johansen <kjlx@templeofstupid.com>
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

vme: Fix wrong pointer utilization in ca91cx42_slave_get

commit c8a6a09c1c617402cc9254b2bc8da359a0347d75 upstream.

In ca91cx42_slave_get function, the value pointed by vme_base pointer is
set through:

*vme_base = ioread32(bridge->base + CA91CX42_VSI_BS[i]);

So it must be dereferenced to be used in calculation of pci_base:

*pci_base = (dma_addr_t)*vme_base + pci_offset;

This bug was caught thanks to the following gcc warning:

drivers/vme/bridges/vme_ca91cx42.c: In function ‘ca91cx42_slave_get’:
drivers/vme/bridges/vme_ca91cx42.c:467:14: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
*pci_base = (dma_addr_t)vme_base + pci_offset;

Signed-off-by: Augusto Mecking Caringi <augustocaringi@gmail.com>
Acked-By: Martyn Welch <martyn@welchs.me.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

xhci: fix deadlock at host remove by running watchdog correctly

commit d6169d04097fd9ddf811e63eae4e5cd71e6666e2 upstream.

If a URB is killed while the host is removed we can end up in a situation
where the hub thread takes the roothub device lock, and waits for
the URB to be given back by xhci-hcd, blocking the host remove code.

xhci-hcd tries to stop the endpoint and give back the urb, but can't
as the host is removed from PCI bus at the same time, preventing the normal
way of giving back urb.

Instead we need to rely on the stop command timeout function to give back
the urb. This xhci_stop_endpoint_command_watchdog() timeout function
used a XHCI_STATE_DYING flag to indicate if the timeout function is already
running, but later this flag has been taking into use in other places to
mark that xhci is dying.

Remove checks for XHCI_STATE_DYING in xhci_urb_dequeue. We are still
checking that reading from pci state does not return 0xffffffff or that
host is not halted before trying to stop the endpoint.

This whole area of stopping endpoints, giving back URBs, and the wathdog
timeout need rework, this fix focuses on solving a specific deadlock
issue that we can then send to stable before any major rework.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

i2c: fix kernel memory disclosure in dev interface

commit 30f939feaeee23e21391cfc7b484f012eb189c3c upstream.

i2c_smbus_xfer() does not always fill an entire block, allowing
kernel stack memory disclosure through the temp variable. Clear
it before it's read to.

Signed-off-by: Vlad Tsyrklevich <vlad@tsyrklevich.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

i2c: print correct device invalid address

commit 6f724fb3039522486fce2e32e4c0fbe238a6ab02 upstream.

In of_i2c_register_device(), when the check for
device address validity fails we print the info.addr,
which has not been assigned properly.

Fix this by printing the actual invalid address.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: b4e2f6ac1281 ("i2c: apply DT flags when probing")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Input: elants_i2c - avoid divide by 0 errors on bad touchscreen data

commit 1c3415a06b1016a596bfe59e0cfee56c773aa958 upstream.

The following crash may be seen if bad data is received from the
touchscreen.

[ 2189.425150] elants_i2c i2c-ELAN0001:00: unknown packet ff ff ff ff
[ 2189.430738] divide error: 0000 [#1] PREEMPT SMP
[ 2189.434679] gsmi: Log Shutdown Reason 0x03
[ 2189.434689] Modules linked in: ip6t_REJECT nf_reject_ipv6 rfcomm evdi
uinput uvcvideo cmac videobuf2_vmalloc videobuf2_memops snd_hda_codec_hdmi
i2c_dev videobuf2_core snd_soc_sst_cht_bsw_rt5645 snd_hda_intel
snd_intel_sst_acpi btusb btrtl btbcm btintel bluetooth snd_soc_sst_acpi
snd_hda_codec snd_intel_sst_core snd_hwdep snd_soc_sst_mfld_platform
snd_hda_core snd_soc_rt5645 memconsole_x86_legacy memconsole zram snd_soc_rl6231
fuse ip6table_filter iwlmvm iwlwifi iwl7000_mac80211 cfg80211 iio_trig_sysfs
joydev cros_ec_sensors cros_ec_sensors_core industrialio_triggered_buffer
kfifo_buf industrialio snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq
snd_seq_device ppp_async ppp_generic slhc tun
[ 2189.434866] CPU: 0 PID: 106 Comm: irq/184-ELAN000 Tainted: G        W
3.18.0-13101-g57e8190 #1
[ 2189.434883] Hardware name: GOOGLE Ultima, BIOS Google_Ultima.7287.131.43 07/20/2016
[ 2189.434898] task: ffff88017a0b6d80 ti: ffff88017a2bc000 task.ti: ffff88017a2bc000
[ 2189.434913] RIP: 0010:[<ffffffffbecc48d5>]  [<ffffffffbecc48d5>] elants_i2c_irq+0x190/0x200
[ 2189.434937] RSP: 0018:ffff88017a2bfd98  EFLAGS: 00010293
[ 2189.434948] RAX: 0000000000000000 RBX: ffff88017a967828 RCX: ffff88017a9678e8
[ 2189.434962] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000000
[ 2189.434975] RBP: ffff88017a2bfdd8 R08: 00000000000003e8 R09: 0000000000000000
[ 2189.434989] R10: 0000000000000000 R11: 000000000044a2bd R12: ffff88017a991800
[ 2189.435001] R13: ffffffffbe8a2a53 R14: ffff88017a0b6d80 R15: ffff88017a0b6d80
[ 2189.435011] FS:  0000000000000000(0000) GS:ffff88017fc00000(0000) knlGS:0000000000000000
[ 2189.435022] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 2189.435030] CR2: 00007f678d94b000 CR3: 000000003f41a000 CR4: 00000000001007f0
[ 2189.435039] Stack:
[ 2189.435044]  ffff88017a2bfda8 ffff88017a9678e8 646464647a2bfdd8 0000000006e09574
[ 2189.435060]  0000000000000000 ffff88017a088b80 ffff88017a921000 ffffffffbe8a2a53
[ 2189.435074]  ffff88017a2bfe08 ffffffffbe8a2a73 ffff88017a0b6d80 0000000006e09574
[ 2189.435089] Call Trace:
[ 2189.435101]  [<ffffffffbe8a2a53>] ? irq_thread_dtor+0xa9/0xa9
[ 2189.435112]  [<ffffffffbe8a2a73>] irq_thread_fn+0x20/0x40
[ 2189.435123]  [<ffffffffbe8a2be1>] irq_thread+0x14e/0x222
[ 2189.435135]  [<ffffffffbee8cbeb>] ? __schedule+0x3b3/0x57a
[ 2189.435145]  [<ffffffffbe8a29aa>] ? wake_threads_waitq+0x2d/0x2d
[ 2189.435156]  [<ffffffffbe8a2a93>] ? irq_thread_fn+0x40/0x40
[ 2189.435168]  [<ffffffffbe87c385>] kthread+0x10e/0x116
[ 2189.435178]  [<ffffffffbe87c277>] ? __kthread_parkme+0x67/0x67
[ 2189.435189]  [<ffffffffbee900ac>] ret_from_fork+0x7c/0xb0
[ 2189.435199]  [<ffffffffbe87c277>] ? __kthread_parkme+0x67/0x67
[ 2189.435208] Code: ff ff eb 73 0f b6 bb c1 00 00 00 83 ff 03 7e 13 49 8d 7c
24 20 ba 04 00 00 00 48 c7 c6 8a cd 21 bf eb 4d 0f b6 83 c2 00 00 00 99 <f7> ff
83 f8 37 75 15 48 6b f7 37 4c 8d a3 c4 00 00 00 4c 8d ac
[ 2189.435312] RIP  [<ffffffffbecc48d5>] elants_i2c_irq+0x190/0x200
[ 2189.435323]  RSP <ffff88017a2bfd98>
[ 2189.435350] ---[ end trace f4945345a75d96dd ]---
[ 2189.443841] Kernel panic - not syncing: Fatal exception
[ 2189.444307] Kernel Offset: 0x3d800000 from 0xffffffff81000000
(relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[ 2189.444519] gsmi: Log Shutdown Reason 0x02

The problem was seen with a 3.18 based kernel, but there is no reason
to believe that the upstream code is safe.

Fixes: 66aee90088da2 ("Input: add support for Elan eKTH I2C touchscreens")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ch341: fix open and resume after B0

commit a20047f36e2f6a1eea4f1fd261aaa55882369868 upstream.

The private baud_rate variable is used to configure the port at open and
reset-resume and must never be set to (and left at) zero or reset-resume
and all further open attempts will fail.

Fixes: aa91def41a7b ("USB: ch341: set tty baud speed according to tty struct")
Fixes: 664d5df92e88 ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ch341: fix control-message error handling

commit 2d5a9c72d0c4ac73cf97f4b7814ed6c44b1e49ae upstream.

A short control transfer would currently fail to be detected, something
which could lead to stale buffer data being used as valid input.

Check for short transfers, and make sure to log any transfer errors.

Note that this also avoids leaking heap data to user space (TIOCMGET)
and the remote device (break control).

Fixes: 6ce76104781a ("USB: Driver for CH341 USB-serial adaptor")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ch341: fix open error handling

commit f2950b78547ffb8475297ada6b92bc2d774d5461 upstream.

Make sure to stop the interrupt URB before returning on errors during
open.

Fixes: 664d5df92e88 ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ch341: fix initial modem-control state

commit 4e2da44691cffbfffb1535f478d19bc2dca3e62b upstream.

DTR and RTS will be asserted by the tty-layer when the port is opened
and deasserted on close (if HUPCL is set). Make sure the initial state
is not-asserted before the port is first opened as well.

Fixes: 664d5df92e88 ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: kl5kusb105: fix line-state error handling

commit 146cc8a17a3b4996f6805ee5c080e7101277c410 upstream.

The current implementation failed to detect short transfers when
attempting to read the line state, and also, to make things worse,
logged the content of the uninitialised heap transfer buffer.

Fixes: abf492e7b3ae ("USB: kl5kusb105: fix DMA buffers on stack")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

nl80211: fix sched scan netlink socket owner destruction

commit 753aacfd2e95df6a0caf23c03dc309020765bea9 upstream.

A single netlink socket might own multiple interfaces *and* a
scheduled scan request (which might belong to another interface),
so when it goes away both may need to be destroyed.

Remove the schedule_scan_stop indirection to fix this - it's only
needed for interface destruction because of the way this works
right now, with a single work taking care of all interfaces.

Fixes: 93a1e86ce10e4 ("nl80211: Stop scheduled scan if netlink client disappears")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

KVM: x86: Introduce segmented_write_std

commit 129a72a0d3c8e139a04512325384fe5ac119e74d upstream.

Introduces segemented_write_std.

Switches from emulated reads/writes to standard read/writes in fxsave,
fxrstor, sgdt, and sidt.  This fixes CVE-2017-2584, a longstanding
kernel memory leak.

Since commit 283c95d0e389 ("KVM: x86: emulate FXSAVE and FXRSTOR",
2016-11-09), which is luckily not yet in any final release, this would
also be an exploitable kernel memory *write*!

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Fixes: 96051572c819194c37a8367624b285be10297eca
Fixes: 283c95d0e3891b64087706b344a4b545d04a6e62
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Steve Rutherford <srutherford@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

KVM: x86: emulate FXSAVE and FXRSTOR

commit 283c95d0e3891b64087706b344a4b545d04a6e62 upstream.

Internal errors were reported on 16 bit fxsave and fxrstor with ipxe.
Old Intels don't have unrestricted_guest, so we have to emulate them.

The patch takes advantage of the hardware implementation.

AMD and Intel differ in saving and restoring other fields in first 32
bytes.  A test wrote 0xff to the fxsave area, 0 to upper bits of MCSXR
in the fxsave area, executed fxrstor, rewrote the fxsave area to 0xee,
and executed fxsave:

  Intel (Nehalem):
    7f 1f 7f 7f ff 00 ff 07 ff ff ff ff ff ff 00 00
    ff ff ff ff ff ff 00 00 ff ff 00 00 ff ff 00 00
  Intel (Haswell -- deprecated FPU CS and FPU DS):
    7f 1f 7f 7f ff 00 ff 07 ff ff ff ff 00 00 00 00
    ff ff ff ff 00 00 00 00 ff ff 00 00 ff ff 00 00
  AMD (Opteron 2300-series):
    7f 1f 7f 7f ff 00 ee ee ee ee ee ee ee ee ee ee
    ee ee ee ee ee ee ee ee ff ff 00 00 ff ff 02 00

fxsave/fxrstor will only be emulated on early Intels, so KVM can't do
much to improve the situation.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

KVM: x86: add asm_safe wrapper

commit aabba3c6abd50b05b1fc2c6ec44244aa6bcda576 upstream.

Move the existing exception handling for inline assembly into a macro
and switch its return values to X86EMUL type.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

KVM: x86: add Align16 instruction flag

commit d3fe959f81024072068e9ed86b39c2acfd7462a9 upstream.

Needed for FXSAVE and FXRSTOR.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

KVM: x86: flush pending lapic jump label updates on module unload

commit cef84c302fe051744b983a92764d3fcca933415d upstream.

KVM's lapic emulation uses static_key_deferred (apic_{hw,sw}_disabled).
These are implemented with delayed_work structs which can still be
pending when the KVM module is unloaded. We've seen this cause kernel
panics when the kvm_intel module is quickly reloaded.

Use the new static_key_deferred_flush() API to flush pending updates on
module unload.

Signed-off-by: David Matlack <dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

jump_labels: API for flushing deferred jump label updates

commit b6416e61012429e0277bd15a229222fd17afc1c1 upstream.

Modules that use static_key_deferred need a way to synchronize with
any delayed work that is still pending when the module is unloaded.
Introduce static_key_deferred_flush() which flushes any pending
jump label updates.

Signed-off-by: David Matlack <dmatlack@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

KVM: eventfd: fix NULL deref irqbypass consumer

commit 4f3dbdf47e150016aacd734e663347fcaa768303 upstream.

Reported syzkaller:

    BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
    IP: irq_bypass_unregister_consumer+0x9d/0xb70 [irqbypass]
    PGD 0

    Oops: 0002 [#1] SMP
    CPU: 1 PID: 125 Comm: kworker/1:1 Not tainted 4.9.0+ #1
    Workqueue: kvm-irqfd-cleanup irqfd_shutdown [kvm]
    task: ffff9bbe0dfbb900 task.stack: ffffb61802014000
    RIP: 0010:irq_bypass_unregister_consumer+0x9d/0xb70 [irqbypass]
    Call Trace:
     irqfd_shutdown+0x66/0xa0 [kvm]
     process_one_work+0x16b/0x480
     worker_thread+0x4b/0x500
     kthread+0x101/0x140
     ? process_one_work+0x480/0x480
     ? kthread_create_on_node+0x60/0x60
     ret_from_fork+0x25/0x30
    RIP: irq_bypass_unregister_consumer+0x9d/0xb70 [irqbypass] RSP: ffffb61802017e20
    CR2: 0000000000000008

The syzkaller folks reported a NULL pointer dereference that due to
unregister an consumer which fails registration before. The syzkaller
creates two VMs w/ an equal eventfd occasionally. So the second VM
fails to register an irqbypass consumer. It will make irqfd as inactive
and queue an workqueue work to shutdown irqfd and unregister the irqbypass
consumer when eventfd is closed. However, the second consumer has been
initialized though it fails registration. So the token(same as the first
VM's) is taken to unregister the consumer through the workqueue, the
consumer of the first VM is found and unregistered, then NULL deref incurred
in the path of deleting consumer from the consumers list.

This patch fixes it by making irq_bypass_register/unregister_consumer()
looks for the consumer entry based on consumer pointer itself instead of
token matching.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

KVM: x86: fix emulation of "MOV SS, null selector"

commit 33ab91103b3415e12457e3104f0e4517ce12d0f3 upstream.

This is CVE-2017-2583.  On Intel this causes a failed vmentry because
SS's type is neither 3 nor 7 (even though the manual says this check is
only done for usable SS, and the dmesg splat says that SS is unusable!).
On AMD it's worse: svm.c is confused and sets CPL to 0 in the vmcb.

The fix fabricates a data segment descriptor when SS is set to a null
selector, so that CPL and SS.DPL are set correctly in the VMCS/vmcb.
Furthermore, only allow setting SS to a NULL selector if SS.RPL < 3;
this in turn ensures CPL < 3 because RPL must be equal to CPL.

Thanks to Andy Lutomirski and Willy Tarreau for help in analyzing
the bug and deciphering the manuals.

Reported-by: Xiaohan Zhang <zhangxiaohan1@huawei.com>
Fixes: 79d5b4c3cd809c770d4bf9812635647016c56011
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mm/hugetlb.c: fix reservation race when freeing surplus pages

commit e5bbc8a6c992901058bc09e2ce01d16c111ff047 upstream.

return_unused_surplus_pages() decrements the global reservation count,
and frees any unused surplus pages that were backing the reservation.

Commit 7848a4bf51b3 ("mm/hugetlb.c: add cond_resched_lock() in
return_unused_surplus_pages()") added a call to cond_resched_lock in the
loop freeing the pages.

As a result, the hugetlb_lock could be dropped, and someone else could
use the pages that will be freed in subsequent iterations of the loop.
This could result in inconsistent global hugetlb page state, application
api failures (such as mmap) failures or application crashes.

When dropping the lock in return_unused_surplus_pages, make sure that
the global reservation count (resv_huge_pages) remains sufficiently
large to prevent someone else from claiming pages about to be freed.

Analyzed by Paul Cassella.

Fixes: 7848a4bf51b3 ("mm/hugetlb.c: add cond_resched_lock() in return_unused_surplus_pages()")
Link: http://lkml.kernel.org/r/1483991767-6879-1-git-send-email-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Paul Cassella <cassella@cray.com>
Suggested-by: Michal Hocko <mhocko@kernel.org>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.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>

ocfs2: fix crash caused by stale lvb with fsdlm plugin

commit e7ee2c089e94067d68475990bdeed211c8852917 upstream.

The crash happens rather often when we reset some cluster nodes while
nodes contend fiercely to do truncate and append.

The crash backtrace is below:

   dlm: C21CBDA5E0774F4BA5A9D4F317717495: dlm_recover_grant 1 locks on 971 resources
   dlm: C21CBDA5E0774F4BA5A9D4F317717495: dlm_recover 9 generation 5 done: 4 ms
   ocfs2: Begin replay journal (node 318952601, slot 2) on device (253,18)
   ocfs2: End replay journal (node 318952601, slot 2) on device (253,18)
   ocfs2: Beginning quota recovery on device (253,18) for slot 2
   ocfs2: Finishing quota recovery on device (253,18) for slot 2
   (truncate,30154,1):ocfs2_truncate_file:470 ERROR: bug expression: le64_to_cpu(fe->i_size) != i_size_read(inode)
   (truncate,30154,1):ocfs2_truncate_file:470 ERROR: Inode 290321, inode i_size = 732 != di i_size = 937, i_flags = 0x1
   ------------[ cut here ]------------
   kernel BUG at /usr/src/linux/fs/ocfs2/file.c:470!
   invalid opcode: 0000 [#1] SMP
   Modules linked in: ocfs2_stack_user(OEN) ocfs2(OEN) ocfs2_nodemanager ocfs2_stackglue(OEN) quota_tree dlm(OEN) configfs fuse sd_mod    iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi af_packet iscsi_ibft iscsi_boot_sysfs softdog xfs libcrc32c ppdev parport_pc pcspkr parport      joydev virtio_balloon virtio_net i2c_piix4 acpi_cpufreq button processor ext4 crc16 jbd2 mbcache ata_generic cirrus virtio_blk ata_piix               drm_kms_helper ahci syscopyarea libahci sysfillrect sysimgblt fb_sys_fops ttm floppy libata drm virtio_pci virtio_ring uhci_hcd virtio ehci_hcd       usbcore serio_raw usb_common sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua scsi_mod autofs4
   Supported: No, Unsupported modules are loaded
   CPU: 1 PID: 30154 Comm: truncate Tainted: G           OE   N  4.4.21-69-default #1
   Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.1-0-g4adadbd-20151112_172657-sheep25 04/01/2014
   task: ffff88004ff6d240 ti: ffff880074e68000 task.ti: ffff880074e68000
   RIP: 0010:[<ffffffffa05c8c30>]  [<ffffffffa05c8c30>] ocfs2_truncate_file+0x640/0x6c0 [ocfs2]
   RSP: 0018:ffff880074e6bd50  EFLAGS: 00010282
   RAX: 0000000000000074 RBX: 000000000000029e RCX: 0000000000000000
   RDX: 0000000000000001 RSI: 0000000000000246 RDI: 0000000000000246
   RBP: ffff880074e6bda8 R08: 000000003675dc7a R09: ffffffff82013414
   R10: 0000000000034c50 R11: 0000000000000000 R12: ffff88003aab3448
   R13: 00000000000002dc R14: 0000000000046e11 R15: 0000000000000020
   FS:  00007f839f965700(0000) GS:ffff88007fc80000(0000) knlGS:0000000000000000
   CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
   CR2: 00007f839f97e000 CR3: 0000000036723000 CR4: 00000000000006e0
   Call Trace:
     ocfs2_setattr+0x698/0xa90 [ocfs2]
     notify_change+0x1ae/0x380
     do_truncate+0x5e/0x90
     do_sys_ftruncate.constprop.11+0x108/0x160
     entry_SYSCALL_64_fastpath+0x12/0x6d
   Code: 24 28 ba d6 01 00 00 48 c7 c6 30 43 62 a0 8b 41 2c 89 44 24 08 48 8b 41 20 48 c7 c1 78 a3 62 a0 48 89 04 24 31 c0 e8 a0 97 f9 ff <0f> 0b 3d 00 fe ff ff 0f 84 ab fd ff ff 83 f8 fc 0f 84 a2 fd ff
   RIP  [<ffffffffa05c8c30>] ocfs2_truncate_file+0x640/0x6c0 [ocfs2]

It's because ocfs2_inode_lock() get us stale LVB in which the i_size is
not equal to the disk i_size.  We mistakenly trust the LVB because the
underlaying fsdlm dlm_lock() doesn't set lkb_sbflags with
DLM_SBF_VALNOTVALID properly for us.  But, why?

The current code tries to downconvert lock without DLM_LKF_VALBLK flag
to tell o2cb don't update RSB's LVB if it's a PR->NULL conversion, even
if the lock resource type needs LVB.  This is not the right way for
fsdlm.

The fsdlm plugin behaves different on DLM_LKF_VALBLK, it depends on
DLM_LKF_VALBLK to decide if we care about the LVB in the LKB.  If
DLM_LKF_VALBLK is not set, fsdlm will skip recovering RSB's LVB from
this lkb and set the right DLM_SBF_VALNOTVALID appropriately when node
failure happens.

The following diagram briefly illustrates how this crash happens:

RSB1 is inode metadata lock resource with LOCK_TYPE_USES_LVB;

The 1st round:

             Node1                                    Node2
RSB1: PR
                                                  RSB1(master): NULL->EX
ocfs2_downconvert_lock(PR->NULL, set_lvb==0)
  ocfs2_dlm_lock(no DLM_LKF_VALBLK)

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

dlm_lock(no DLM_LKF_VALBLK)
  convert_lock(overwrite lkb->lkb_exflags
               with no DLM_LKF_VALBLK)

RSB1: NULL                                        RSB1: EX
                                                  reset Node2
dlm_recover_rsbs()
  recover_lvb()

/* The LVB is not trustable if the node with EX fails and
 * no lock >= PR is left. We should set RSB_VALNOTVALID for RSB1.
 */

 if(!(kb_exflags & DLM_LKF_VALBLK)) /* This means we miss the chance to
           return;                   * to invalid the LVB here.
                                     */

The 2nd round:

         Node 1                                Node2
RSB1(become master from recovery)

ocfs2_setattr()
  ocfs2_inode_lock(NULL->EX)
    /* dlm_lock() return the stale lvb without setting DLM_SBF_VALNOTVALID */
    ocfs2_meta_lvb_is_trustable() return 1 /* so we don't refresh inode from disk */
  ocfs2_truncate_file()
      mlog_bug_on_msg(disk isize != i_size_read(inode))  /* crash! */

The fix is quite straightforward.  We keep to set DLM_LKF_VALBLK flag
for dlm_lock() if the lock resource type needs LVB and the fsdlm plugin
is uesed.

Link: http://lkml.kernel.org/r/1481275846-6604-1-git-send-email-zren@suse.com
Signed-off-by: Eric Ren <zren@suse.com>
Reviewed-by: Joseph Qi <jiangqi903@gmail.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.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>

mm: fix devm_memremap_pages crash, use mem_hotplug_{begin, done}

commit f931ab479dd24cf7a2c6e2df19778406892591fb upstream.

Both arch_add_memory() and arch_remove_memory() expect a single threaded
context.

For example, arch/x86/mm/init_64.c::kernel_physical_mapping_init() does
not hold any locks over this check and branch:

    if (pgd_val(*pgd)) {
     pud = (pud_t *)pgd_page_vaddr(*pgd);
     paddr_last = phys_pud_init(pud, __pa(vaddr),
        __pa(vaddr_end),
        page_size_mask);
     continue;
    }

    pud = alloc_low_page();
    paddr_last = phys_pud_init(pud, __pa(vaddr), __pa(vaddr_end),
        page_size_mask);

The result is that two threads calling devm_memremap_pages()
simultaneously can end up colliding on pgd initialization.  This leads
to crash signatures like the following where the loser of the race
initializes the wrong pgd entry:

    BUG: unable to handle kernel paging request at ffff888ebfff0000
    IP: memcpy_erms+0x6/0x10
    PGD 2f8e8fc067 PUD 0 /* <---- Invalid PUD */
    Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
    CPU: 54 PID: 3818 Comm: systemd-udevd Not tainted 4.6.7+ #13
    task: ffff882fac290040 ti: ffff882f887a4000 task.ti: ffff882f887a4000
    RIP: memcpy_erms+0x6/0x10
    [..]
    Call Trace:
      ? pmem_do_bvec+0x205/0x370 [nd_pmem]
      ? blk_queue_enter+0x3a/0x280
      pmem_rw_page+0x38/0x80 [nd_pmem]
      bdev_read_page+0x84/0xb0

Hold the standard memory hotplug mutex over calls to
arch_{add,remove}_memory().

Fixes: 41e94a851304 ("add devm_memremap_pages")
Link: http://lkml.kernel.org/r/148357647831.9498.12606007370121652979.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
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>

selftests: do not require bash for the generated test

commit a2b1e8a20c992b01eeb76de00d4f534cbe9f3822 upstream.

Nothing in this minimal script seems to require bash. We often run these
tests on embedded devices where the only shell available is the busybox
ash. Use sh instead.

Signed-off-by: Rolf Eike Beer <eb@emlix.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

selftests: do not require bash to run netsocktests testcase

commit 3659f98b5375d195f1870c3e508fe51e52206839 upstream.

Nothing in this minimal script seems to require bash. We often run these
tests on embedded devices where the only shell available is the busybox
ash. Use sh instead.

Signed-off-by: Rolf Eike Beer <eb@emlix.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Input: i8042 - add Pegatron touchpad to noloop table

commit 41c567a5d7d1a986763e58c3394782813c3bcb03 upstream.

Avoid AUX loopback in Pegatron C15B touchpad, so input subsystem is able
to recognize a Synaptics touchpad in the AUX port.

Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=93791
(Touchpad is not detected on DNS 0801480 notebook (PEGATRON C15B))

Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Input: xpad - use correct product id for x360w controllers

commit b6fc513da50c5dbc457a8ad6b58b046a6a68fd9d upstream.

currently the controllers get the same product id as the wireless
receiver. However the controllers actually have their own product id.

The patch makes the driver expose the same product id as the windows
driver.

This improves compatibility when running applications with WINE.

see https://github.com/paroj/xpad/issues/54

Signed-off-by: Pavel Rojtberg <rojtberg@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

DEBUG: sched/fair: Fix sched_load_avg_cpu events for task_groups

The current sched_load_avg_cpu event traces the load for any cfs_rq that is
updated. This is not representative of the CPU load - instead we should only
trace this event when the cfs_rq being updated is in the root_task_group.

Change-Id: I345c2f13f6b5718cb4a89beb247f7887ce97ed6b
Signed-off-by: Brendan Jackman <brendan.jackman@arm.com>

DEBUG: sched/fair: Fix missing sched_load_avg_cpu events

update_cfs_rq_load_avg is called from update_blocked_averages without triggering
the sched_load_avg_cpu event. Move the event trigger to inside
update_cfs_rq_load_avg to avoid this missing event.

Change-Id: I6c4f66f687a644e4e7f798db122d28a8f5919b7b
Signed-off-by: Brendan Jackman <brendan.jackman@arm.com>

net: socket: don't set sk_uid to garbage value in ->setattr()

->setattr() was recently implemented for socket files to sync the socket
inode's uid to the new 'sk_uid' member of struct sock.  It does this by
copying over the ia_uid member of struct iattr.  However, ia_uid is
actually only valid when ATTR_UID is set in ia_valid, indicating that
the uid is being changed, e.g. by chown.  Other metadata operations such
as chmod or utimes leave ia_uid uninitialized.  Therefore, sk_uid could
be set to a "garbage" value from the stack.

Fix this by only copying the uid over when ATTR_UID is set.

[cherry-pick of net e1a3a60a2ebe991605acb14cd58e39c0545e174e]

Bug: 16355602
Change-Id: I20e53848e54282b72a388ce12bfa88da5e3e9efe
Fixes: 86741ec25462 ("net: core: Add a UID field to struct sock.")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Lorenzo Colitti <lorenzo@google.com>
Acked-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ANDROID: configs: CONFIG_ARM64_SW_TTBR0_PAN=y

Bug: 31432001
Change-Id: Ia72c3aa70a463d3a7f52b76e5082520aa328d29b
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

UPSTREAM: arm64: Disable PAN on uaccess_enable()

Commit 4b65a5db3627 ("arm64: Introduce uaccess_{disable,enable}
functionality based on TTBR0_EL1") added conditional user access
enable/disable. Unfortunately, a typo prevents the PAN bit from being
cleared for user access functions.

Restore the PAN functionality by adding the missing '!'.

Fixes: b65a5db3627 ("arm64: Introduce uaccess_{disable,enable} functionality based on TTBR0_EL1")
Reported-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Bug: 31432001
Change-Id: If61cb6cc756affc7df7fa06213723a8b96eb1e80
(cherry picked from commit 75037120e62b58c536999eb23d70cfcb6d6c0bcc)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

UPSTREAM: arm64: Enable CONFIG_ARM64_SW_TTBR0_PAN

This patch adds the Kconfig option to enable support for TTBR0 PAN
emulation. The option is default off because of a slight performance hit
when enabled, caused by the additional TTBR0_EL1 switching during user
access operations or exception entry/exit code.

Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Bug: 31432001
Change-Id: I2f0b5f332e3c56ea0453ff69826525dec49f034b
(cherry picked from commit ba42822af1c287f038aa550f3578c61c212a892e)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

UPSTREAM: arm64: xen: Enable user access before a privcmd hvc call

Privcmd calls are issued by the userspace. The kernel needs to enable
access to TTBR0_EL1 as the hypervisor would issue stage 1 translations
to user memory via AT instructions. Since AT instructions are not
affected by the PAN bit (ARMv8.1), we only need the explicit
uaccess_enable/disable if the TTBR0 PAN option is enabled.

Reviewed-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Bug: 31432001
Change-Id: I64d827923d869c1868702c8a18efa99ea91d3151
(cherry picked from commit 9cf09d68b89ae5fe0261dcc69464bcc676900af6)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

UPSTREAM: arm64: Handle faults caused by inadvertent user access with PAN enabled

When TTBR0_EL1 is set to the reserved page, an erroneous kernel access
to user space would generate a translation fault. This patch adds the
checks for the software-set PSR_PAN_BIT to emulate a permission fault
and report it accordingly.

Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Bug: 31432001
Change-Id: I87e48f6075f84878e4d26d4fadf6eaac49d2cb4e
(cherry picked from commit 786889636ad75296c213547d1ca656af4c59f390)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

BACKPORT: arm64: Disable TTBR0_EL1 during normal kernel execution

When the TTBR0 PAN feature is enabled, the kernel entry points need to
disable access to TTBR0_EL1. The PAN status of the interrupted context
is stored as part of the saved pstate, reusing the PSR_PAN_BIT (22).
Restoring access to TTBR0_EL1 is done on exception return if returning
to user or returning to a context where PAN was disabled.

Context switching via switch_mm() must defer the update of TTBR0_EL1
until a return to user or an explicit uaccess_enable() call.

Special care needs to be taken for two cases where TTBR0_EL1 is set
outside the normal kernel context switch operation: EFI run-time
services (via efi_set_pgd) and CPU suspend (via cpu_(un)install_idmap).
Code has been added to avoid deferred TTBR0_EL1 switching as in
switch_mm() and restore the reserved TTBR0_EL1 when uninstalling the
special TTBR0_EL1.

User cache maintenance (user_cache_maint_handler and
__flush_cache_user_range) needs the TTBR0_EL1 re-instated since the
operations are performed by user virtual address.

This patch also removes a stale comment on the switch_mm() function.

Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Bug: 31432001
Change-Id: I85a49f70e13b153b9903851edf56f6531c14e6de
(cherry picked from commit 39bc88e5e38e9b213bd7d833ce0df6ec029761ad)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

BACKPORT: arm64: Introduce uaccess_{disable,enable} functionality based on TTBR0_EL1

This patch adds the uaccess macros/functions to disable access to user
space by setting TTBR0_EL1 to a reserved zeroed page. Since the value
written to TTBR0_EL1 must be a physical address, for simplicity this
patch introduces a reserved_ttbr0 page at a constant offset from
swapper_pg_dir. The uaccess_disable code uses the ttbr1_el1 value
adjusted by the reserved_ttbr0 offset.

Enabling access to user is done by restoring TTBR0_EL1 with the value
from the struct thread_info ttbr0 variable. Interrupts must be disabled
during the uaccess_ttbr0_enable code to ensure the atomicity of the
thread_info.ttbr0 read and TTBR0_EL1 write. This patch also moves the
get_thread_info asm macro from entry.S to assembler.h for reuse in the
uaccess_ttbr0_* macros.

Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Bug: 31432001
Change-Id: I54ada623160cb47f5762e0e39a5e84a75252dbfd
(cherry picked from commit 4b65a5db362783ab4b04ca1c1d2ad70ed9b0ba2a)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

BACKPORT: arm64: Factor out TTBR0_EL1 post-update workaround into a specific asm macro

This patch takes the errata workaround code out of cpu_do_switch_mm into
a dedicated post_ttbr0_update_workaround macro which will be reused in a
subsequent patch.

Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Bug: 31432001
Change-Id: I2b45b11ab7390c3545b9e162532109c1526bef14
(cherry picked from commit f33bcf03e6079668da6bf4eec4a7dcf9289131d0)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

BACKPORT: arm64: Factor out PAN enabling/disabling into separate uaccess_* macros

This patch moves the directly coded alternatives for turning PAN on/off
into separate uaccess_{enable,disable} macros or functions. The asm
macros take a few arguments which will be used in subsequent patches.

Note that any (unlikely) access that the compiler might generate between
uaccess_enable() and uaccess_disable(), other than those explicitly
specified by the user access code, will not be protected by PAN.

Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Bug: 31432001
Change-Id: I75a410139d0756edab3210ee091fa5d047a22e04
(cherry picked from commit bd38967d406fb4f9fca67d612db71b5d74cfb0f5)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

UPSTREAM: arm64: alternative: add auto-nop infrastructure

In some cases, one side of an alternative sequence is simply a number of
NOPs used to balance the other side. Keeping track of this manually is
tedious, and the presence of large chains of NOPs makes the code more
painful to read than necessary.

To ameliorate matters, this patch adds a new alternative_else_nop_endif,
which automatically balances an alternative sequence with a trivial NOP
sled.

In many cases, we would like a NOP-sled in the default case, and
instructions patched in in the presence of a feature. To enable the NOPs
to be generated automatically for this case, this patch also adds a new
alternative_if, and updates alternative_else and alternative_endif to
work with either alternative_if or alternative_endif.

Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Martin <dave.martin@arm.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
[will: use new nops macro to generate nop sequences]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Bug: 31432001
Change-Id: I28d8aae073e113048577c41cfe27c91215fb4cf3
(cherry picked from commit 792d47379f4d4c76692f1795f33d38582f8907fa)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

UPSTREAM: arm64: barriers: introduce nops and __nops macros for NOP sequences

NOP sequences tend to get used for padding out alternative sections
and uarch-specific pipeline flushes in errata workarounds.

This patch adds macros for generating these sequences as both inline
asm blocks, but also as strings suitable for embedding in other asm
blocks directly.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Bug: 31432001
Change-Id: I7f82b677a065ede302a763d39ffcc3fef83f8fbe
(cherry picked from commit f99a250cb6a3b301b101b4c0f5fcb80593bba6dc)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

Revert "FROMLIST: arm64: Factor out PAN enabling/disabling into separate uaccess_* macros"

This reverts commit 23368b642deb01ac6ce668ec1dedfcc0cab25c71.

Bug: 31432001
Change-Id: Ia59e5fc75ef905b89d5f9194f1e762c1e5eff5bf
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

Revert "FROMLIST: arm64: Factor out TTBR0_EL1 post-update workaround into a specific asm macro"

This reverts commit 3b66929169de053042d47e482dd5748794756153.

Bug: 31432001
Change-Id: Ib38fcf553ca2077531cbf550fbaa75378a8723c5
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

Revert "FROMLIST: arm64: Introduce uaccess_{disable,enable} functionality based on TTBR0_EL1"

This reverts commit 1911d36b27ba58ee18592df25b7ee636d4d4c41d.

Bug: 31432001
Change-Id: Iee77eed8454f379b948dbbaf65c105952ea30bef
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

Revert "FROMLIST: arm64: Disable TTBR0_EL1 during normal kernel execution"

This reverts commit 5775ca34829caf0664c8ccc02fd0e93cb6022e0f.

Bug: 31432001
Change-Id: I9b07c2f01bc2bcfed51f60ab487034639f5e1960
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

Revert "FROMLIST: arm64: Handle faults caused by inadvertent user access with PAN enabled"

This reverts commit 0a75f2be2d16a271d64b20f9dc7de3e2629652a1.

Revert "FROMLIST: arm64: xen: Enable user access before a privcmd hvc call"

This reverts commit 4dbc88bd2b6a74fd33483ee2593dcf2bd858eabe.

Bug: 31432001
Change-Id: I2c3d591a2c631e7ff02c0bcb91624735e8c12f0a
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

Revert "FROMLIST: arm64: Enable CONFIG_ARM64_SW_TTBR0_PAN"

This reverts commit 67cd3bda54dadba4f8892105adf9c2f3982bfa0a.

Bug: 31432001
Change-Id: I1e5836ce0b41b2262d95c5c4c49ace3b96ae0b1f
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>