Clients must be able to read a file in order to execute it, and for pNFS
that means the client needs to be able to perform a LAYOUTGET on the file.

This behavior for executable-only files was added for OPEN in commit
a043226b "nfsd4: permit read opens of executable-only files".

This fixes up xfstests generic/126 on block/scsi layouts.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

atomic_t variables are currently used to implement reference
counters with the following properties:
 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable nlm_rqst.a_count is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

**Important note for maintainers:

Some functions from refcount_t API defined in lib/refcount.c
have different memory ordering guarantees than their atomic
counterparts.
The full comparison can be seen in
https://lkml.org/lkml/2017/11/15/57 and it is hopefully soon
in state to be merged to the documentation tree.
Normally the differences should not matter since refcount_t provides
enough guarantees to satisfy the refcounting use cases, but in
some rare cases it might matter.
Please double check that you don't have some undocumented
memory guarantees for this variable usage.

For the nlm_rqst.a_count it might make a difference
in following places:
 - nlmclnt_release_call() and nlmsvc_release_call(): decrement
   in refcount_dec_and_test() only
   provides RELEASE ordering and control dependency on success
   vs. fully ordered atomic counterpart
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

atomic_t variables are currently used to implement reference
counters with the following properties:
 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable nlm_lockowner.count is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

**Important note for maintainers:

Some functions from refcount_t API defined in lib/refcount.c
have different memory ordering guarantees than their atomic
counterparts.
The full comparison can be seen in
https://lkml.org/lkml/2017/11/15/57 and it is hopefully soon
in state to be merged to the documentation tree.
Normally the differences should not matter since refcount_t provides
enough guarantees to satisfy the refcounting use cases, but in
some rare cases it might matter.
Please double check that you don't have some undocumented
memory guarantees for this variable usage.

For the nlm_lockowner.count it might make a difference
in following places:
 - nlm_put_lockowner(): decrement in refcount_dec_and_lock() only
   provides RELEASE ordering, control dependency on success and
   holds a spin lock on success vs. fully ordered atomic counterpart.
   No changes in spin lock guarantees.
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

atomic_t variables are currently used to implement reference
counters with the following properties:
 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable nsm_handle.sm_count is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

**Important note for maintainers:

Some functions from refcount_t API defined in lib/refcount.c
have different memory ordering guarantees than their atomic
counterparts.
The full comparison can be seen in
https://lkml.org/lkml/2017/11/15/57 and it is hopefully soon
in state to be merged to the documentation tree.
Normally the differences should not matter since refcount_t provides
enough guarantees to satisfy the refcounting use cases, but in
some rare cases it might matter.
Please double check that you don't have some undocumented
memory guarantees for this variable usage.

For the nsm_handle.sm_count it might make a difference
in following places:
 - nsm_release(): decrement in refcount_dec_and_lock() only
   provides RELEASE ordering, control dependency on success
   and holds a spin lock on success vs. fully ordered atomic
   counterpart. No change for the spin lock guarantees.
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

restart_grace() uses hardcoded init_net.
It can cause to "list_add double add" in following scenario:

1) nfsd and lockd was started in several net namespaces
2) nfsd in init_net was stopped (lockd was not stopped because
 it have users from another net namespaces)
3) lockd got signal, called restart_grace() -> set_grace_period()
 and enabled lock_manager in hardcoded init_net.
4) nfsd in init_net is started again,
 its lockd_up() calls set_grace_period() and tries to add
 lock_manager into init_net 2nd time.

Jeff Layton suggest:
"Make it safe to call locks_start_grace multiple times on the same
lock_manager. If it's already on the global grace_list, then don't try
to add it again.  (But we don't intentionally add twice, so for now we
WARN about that case.)

With this change, we also need to ensure that the nfsd4 lock manager
initializes the list before we call locks_start_grace. While we're at
it, move the rest of the nfsd_net initialization into
nfs4_state_create_net. I see no reason to have it spread over two
functions like it is today."

Suggested patch was updated to generate warning in described situation.
Suggested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

nlm_complain_hosts() walks through nlm_server_hosts hlist, which should
be protected by nlm_host_mutex.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

nfsd_inet[6]addr_event uses nn->nfsd_serv without taking nfsd_mutex,
which can be changed during execution of notifiers and crash the host.

Moreover if notifiers were enabled in one net namespace they are enabled
in all other net namespaces, from creation until destruction.

This patch allows notifiers to access nn->nfsd_serv only after the
pointer is correctly initialized and delays cleanup until notifiers are
no longer in use.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Tested-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

lockd_inet[6]addr_event use nlmsvc_rqst without taken nlmsvc_mutex,
nlmsvc_rqst can be changed during execution of notifiers and crash the host.

Patch enables access to nlmsvc_rqst only when it was correctly initialized
and delays its cleanup until notifiers are no longer in use.

Note that nlmsvc_rqst can be temporally set to ERR_PTR, so the "if
(nlmsvc_rqst)" check in notifiers is insufficient on its own.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Tested-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Make these const as they are only getting passed to the function
cache_create_net having the argument as const.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Make these const as they are only getting passed to the function
cache_create_net having the argument as const.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Make the struct cache_detail *tmpl argument of the function
cache_create_net as const as it is only getting passed to kmemup having
the argument as const void *.
Add const to the prototype too.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Prevent the use of the closed (invalid) special stateid by clients.
Signed-off-by: Andrew Elble <aweits@rit.edu>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

From kernel 4.9, my two nfsv4 servers sometimes suffer from
    "panic: unable to handle kernel page request"
in posix_unblock_lock() called from nfs4_laundromat().

These panics diseappear if we revert the commit "nfsd: add a LRU list
for blocked locks".

The cause appears to be a typo in nfs4_laundromat(), which is also
present in nfs4_state_shutdown_net().

Cc: stable@vger.kernel.org
Fixes: 7919d0a2 "nfsd: add a LRU list for blocked locks"
Cc: jlayton@redhat.com
Reveiwed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Commit efda760f ("lockd: fix lockd shutdown race") is incorrect,
it removes lockd_manager and disarm grace_period_end for init_net only.

If nfsd was started from another net namespace lockd_up_net() calls
set_grace_period() that adds lockd_manager into per-netns list
and queues grace_period_end delayed work.

These action should be reverted in lockd_down_net().
Otherwise it can lead to double list_add on after restart nfsd in netns,
and to use-after-free if non-disarmed delayed work will be executed after netns destroy.

Fixes: efda760f ("lockd: fix lockd shutdown race")
Cc: stable@vger.kernel.org
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The use of the st_mutex has been confusing the validator. Use the
proper nested notation so as to not produce warnings.
Signed-off-by: Andrew Elble <aweits@rit.edu>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Publishing of net pointer is not safe,
use net->ns.inum as net ID in debug messages

[  171.757678] lockd_up_net: per-net data created; net=f00001e7
[  171.767188] NFSD: starting 90-second grace period (net f00001e7)
[  300.653313] lockd: nuking all hosts in net f00001e7...
[  300.653641] lockd: host garbage collection for net f00001e7
[  300.653968] lockd: nlmsvc_mark_resources for net f00001e7
[  300.711483] lockd_down_net: per-net data destroyed; net=f00001e7
[  300.711847] lockd: nuking all hosts in net 0...
[  300.711847] lockd: host garbage collection for net 0
[  300.711848] lockd: nlmsvc_mark_resources for net 0
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Publishing of net pointer is not safe,
replace it in debug meesages by net->ns.inum

[  119.989161] nfsd: initializing export module (net: f00001e7).
[  171.767188] NFSD: starting 90-second grace period (net f00001e7)
[  322.185240] nfsd: shutting down export module (net: f00001e7).
[  322.186062] nfsd: export shutdown complete (net: f00001e7).
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The various functions that call check_stateid_generation() in order
to compare a client-supplied stateid with the nfs4_stid state, usually
need to atomically check for closed state. Those that perform the
check after locking the st_mutex using nfsd4_lock_ol_stateid()
should now be OK, but we do want to fix up the others.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

After taking the stateid st_mutex, we want to know that the stateid
still represents valid state before performing any non-idempotent
actions.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

If we're looking up a new lock state, and the creation fails, then
we want to unhash it, just like we do for OPEN. However in order
to do so, we need to that no other LOCK requests can grab the
mutex until we have unhashed it (and marked it as closed).
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Trivial cleanup to simplify following patch.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

In order to deal with lookup races, nfsd4_free_lock_stateid() needs
to be able to signal to other stateful functions that the lock stateid
is no longer valid. Right now, nfsd_lock() will check whether or not an
existing stateid is still hashed, but only in the "new lock" path.

To ensure the stateid invalidation is also recognised by the "existing lock"
path, and also by a second call to nfsd4_free_lock_stateid() itself, we can
change the type to NFS4_CLOSED_STID under the stp->st_mutex.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

If nfsd4_process_open2() is initialising a new stateid, and yet the
call to nfs4_get_vfs_file() fails for some reason, then we must
declare the stateid closed, and unhash it before dropping the mutex.

Right now, we unhash the stateid after dropping the mutex, and without
changing the stateid type, meaning that another OPEN could theoretically
look it up and attempt to use it.
Reported-by: Andrew W Elble <aweits@rit.edu>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Open file stateids can linger on the nfs4_file list of stateids even
after they have been closed. In order to avoid reusing such a
stateid, and confusing the client, we need to recheck the
nfs4_stid's type after taking the mutex.
Otherwise, we risk reusing an old stateid that was already closed,
which will confuse clients that expect new stateids to conform to
RFC7530 Sections 9.1.4.2 and 16.2.5 or RFC5661 Sections 8.2.2 and 18.2.4.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Pull ARM fixes from Russell King:

 - LPAE fixes for kernel-readonly regions

 - Fix for get_user_pages_fast on LPAE systems

 - avoid tying decompressor to a particular platform if DEBUG_LL is
   enabled

 - BUG if we attempt to return to userspace but the to-be-restored PSR
   value keeps us in privileged mode (defeating an issue that ftracetest
   found)

* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: BUG if jumping to usermode address in kernel mode
  ARM: 8722/1: mm: make STRICT_KERNEL_RWX effective for LPAE
  ARM: 8721/1: mm: dump: check hardware RO bit for LPAE
  ARM: make decompressor debug output user selectable
  ARM: fix get_user_pages_fast

Pull irq fixes from Thomas Glexiner:

 - unbreak the irq trigger type check for legacy platforms

 - a handful fixes for ARM GIC v3/4 interrupt controllers

 - a few trivial fixes all over the place

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/matrix: Make - vs ?: Precedence explicit
  irqchip/imgpdc: Use resource_size function on resource object
  irqchip/qcom: Fix u32 comparison with value less than zero
  irqchip/exiu: Fix return value check in exiu_init()
  irqchip/gic-v3-its: Remove artificial dependency on PCI
  irqchip/gic-v4: Add forward definition of struct irq_domain_ops
  irqchip/gic-v3: pr_err() strings should end with newlines
  irqchip/s3c24xx: pr_err() strings should end with newlines
  irqchip/gic-v3: Fix ppi-partitions lookup
  irqchip/gic-v4: Clear IRQ_DISABLE_UNLAZY again if mapping fails
  genirq: Track whether the trigger type has been set

Pull misc x86 fixes from Ingo Molnar:
 - topology enumeration fixes
 - KASAN fix
 - two entry fixes (not yet the big series related to KASLR)
 - remove obsolete code
 - instruction decoder fix
 - better /dev/mem sanity checks, hopefully working better this time
 - pkeys fixes
 - two ACPI fixes
 - 5-level paging related fixes
 - UMIP fixes that should make application visible faults more debuggable
 - boot fix for weird virtualization environment

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/decoder: Add new TEST instruction pattern
  x86/PCI: Remove unused HyperTransport interrupt support
  x86/umip: Fix insn_get_code_seg_params()'s return value
  x86/boot/KASLR: Remove unused variable
  x86/entry/64: Add missing irqflags tracing to native_load_gs_index()
  x86/mm/kasan: Don't use vmemmap_populate() to initialize shadow
  x86/entry/64: Fix entry_SYSCALL_64_after_hwframe() IRQ tracing
  x86/pkeys/selftests: Fix protection keys write() warning
  x86/pkeys/selftests: Rename 'si_pkey' to 'siginfo_pkey'
  x86/mpx/selftests: Fix up weird arrays
  x86/pkeys: Update documentation about availability
  x86/umip: Print a warning into the syslog if UMIP-protected instructions are used
  x86/smpboot: Fix __max_logical_packages estimate
  x86/topology: Avoid wasting 128k for package id array
  perf/x86/intel/uncore: Cache logical pkg id in uncore driver
  x86/acpi: Reduce code duplication in mp_override_legacy_irq()
  x86/acpi: Handle SCI interrupts above legacy space gracefully
  x86/boot: Fix boot failure when SMP MP-table is based at 0
  x86/mm: Limit mmap() of /dev/mem to valid physical addresses
  x86/selftests: Add test for mapping placement for 5-level paging
  ...

Pull scheduler fixes from Ingo Molnar:
 "Misc fixes: a documentation fix, a Sparse warning fix and a debugging
  fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/debug: Fix task state recording/printout
  sched/deadline: Don't use dubious signed bitfields
  sched/deadline: Fix the description of runtime accounting in the documentation

Pull perf fixes from Ingo Molnar:
 "Misc fixes: two PMU driver fixes and a memory leak fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Fix memory leak triggered by perf --namespace
  perf/x86/intel/uncore: Add event constraint for BDX PCU
  perf/x86/intel: Hide TSX events when RTM is not supported

Pull static key fix from Ingo Molnar:
 "Fix a boot warning related to bad init ordering of the static keys
  self-test"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  jump_label: Invoke jump_label_test() via early_initcall()

Pull objtool fixes from Ingo Molnar:
 "A handful of objtool fixes, most of them related to making the UAPI
  header-syncing warnings easier to read and easier to act upon"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools/headers: Sync objtool UAPI header
  objtool: Fix cross-build
  objtool: Move kernel headers/code sync check to a script
  objtool: Move synced files to their original relative locations
  objtool: Make unreachable annotation inline asms explicitly volatile
  objtool: Add a comment for the unreachable annotation macros

Detect if we are returning to usermode via the normal kernel exit paths
but the saved PSR value indicates that we are in kernel mode.  This
could occur due to corrupted stack state, which has been observed with
"ftracetest".

This ensures that we catch the problem case before we get to user code.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Pull timer updates from Thomas Gleixner:

 - The final conversion of timer wheel timers to timer_setup().

   A few manual conversions and a large coccinelle assisted sweep and
   the removal of the old initialization mechanisms and the related
   code.

 - Remove the now unused VSYSCALL update code

 - Fix permissions of /proc/timer_list. I still need to get rid of that
   file completely

 - Rename a misnomed clocksource function and remove a stale declaration

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
  m68k/macboing: Fix missed timer callback assignment
  treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts
  timer: Remove redundant __setup_timer*() macros
  timer: Pass function down to initialization routines
  timer: Remove unused data arguments from macros
  timer: Switch callback prototype to take struct timer_list * argument
  timer: Pass timer_list pointer to callbacks unconditionally
  Coccinelle: Remove setup_timer.cocci
  timer: Remove setup_*timer() interface
  timer: Remove init_timer() interface
  treewide: setup_timer() -> timer_setup() (2 field)
  treewide: setup_timer() -> timer_setup()
  treewide: init_timer() -> setup_timer()
  treewide: Switch DEFINE_TIMER callbacks to struct timer_list *
  s390: cmm: Convert timers to use timer_setup()
  lightnvm: Convert timers to use timer_setup()
  drivers/net: cris: Convert timers to use timer_setup()
  drm/vc4: Convert timers to use timer_setup()
  block/laptop_mode: Convert timers to use timer_setup()
  net/atm/mpc: Avoid open-coded assignment of timer callback function
  ...

Pull ARC updates from Vineet Gupta:

 - more changes for HS48 cores: supporting MMUv5, detecting new
   micro-arch gizmos

 - axs10x platform wiring up reset driver merged in this cycle

 - ARC perf driver optimizations

* tag 'arc-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: perf: avoid vmalloc backed mmap
  ARCv2: perf: optimize given that num counters <= 32
  ARCv2: perf: tweak overflow interrupt
  ARC: [plat-axs10x] DTS: Add reset controller node to manage ethernet reset
  ARCv2: boot log: updates for HS48: dual-issue, ECC, Loop Buffer
  ARCv2: Accomodate HS48 MMUv5 by relaxing MMU ver checking
  ARC: [plat-axs10x] auto-select AXS101 or AXS103 given the  ISA config

Pull more Kbuild updates from Masahiro Yamada:

 - use 'pwd' instead of '/bin/pwd' for portability

 - clean up Makefiles

 - fix ld-option for clang

 - fix malloc'ed data size in Kconfig

 - fix parallel building along with coccicheck

 - fix a minor issue of package building

 - prompt to use "rpm-pkg" instead of "rpm"

 - clean up *.i and *.lst patterns by "make clean"

* tag 'kbuild-v4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: drop $(extra-y) from real-objs-y
  kbuild: clean up *.i and *.lst patterns by make clean
  kbuild: rpm: prompt to use "rpm-pkg" if "rpm" target is used
  kbuild: pkg: use --transform option to prefix paths in tar
  coccinelle: fix parallel build with CHECK=scripts/coccicheck
  kconfig/symbol.c: use correct pointer type argument for sizeof
  kbuild: Set KBUILD_CFLAGS before incl. arch Makefile
  kbuild: remove all dummy assignments to obj-
  kbuild: create built-in.o automatically if parent directory wants it
  kbuild: /bin/pwd -> pwd

Pull AFS fixes from David Howells:

 - Make AFS file locking work again.

 - Don't write to a page that's being written out, but wait for it to
   complete.

 - Do d_drop() and d_add() in the right places.

 - Put keys on error paths.

 - Remove some redundant code.

* tag 'afs-fixes-20171124' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: remove redundant assignment of dvnode to itself
  afs: cell: Remove unnecessary code in afs_lookup_cell
  afs: Fix signal handling in some file ops
  afs: Fix some dentry handling in dir ops and missing key_puts
  afs: Make afs_write_begin() avoid writing to a page that's being stored
  afs: Fix file locking