Merge tag 'iio-fixes-for-5.6a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus

Jonathan writes:

First set of IIO fixes in the 5.6 cycle.

* adxl372
  - Fix marking of buffered values as big endian.
* ak8974
  - Fix wrong handling of negative values when read from sysfs.
* at91-sama5d2
  - Fix differential mode by ensuring configuration set correctly.
* ping
  - Use the write sensor type for of_ping_match table.
* sps30
  - Kconfig build dependency fix.
* st-sensors
  - Fix a wrong identification of which part the SMO8840 ACPI ID indicates.
* stm32-dsfdm
  - Fix a sleep in atomic issue by not using a trigger when it makes no sense.
* stm32-timer
  - Make sure master mode is disabled when stopping.
* vcnl400
  - Update some sampling periods based on new docs.

* tag 'iio-fixes-for-5.6a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio:
  iio: ping: set pa_laser_ping_cfg in of_ping_match
  iio: chemical: sps30: fix missing triggered buffer dependency
  iio: st_sensors: remap SMO8840 to LIS2DH12
  iio: light: vcnl4000: update sampling periods for vcnl4040
  iio: light: vcnl4000: update sampling periods for vcnl4200
  iio: accel: adxl372: Set iio_chan BE
  iio: magnetometer: ak8974: Fix negative raw values in sysfs
  iio: trigger: stm32-timer: disable master mode when stopping
  iio: adc: stm32-dfsdm: fix sleep in atomic context
  iio: adc: at91-sama5d2_adc: fix differential channels in triggered mode

This device was added to the stand-alone driver on github.
Add it to the staging driver as well.

Link: https://github.com/lwfinger/rtl8188eu/commit/2141f244c3e7Signed-off-by: Michael Straube <straube.linux@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200312093652.13918-1-straube.linux@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Newer GCC warns about possible truncations of two generated path names as
we're concatenating the configurable sysfs and debugfs path prefixes
with a filename and placing the results in buffers of the same size as
the maximum length of the prefixes.

	snprintf(d->name, MAX_STR_LEN, "gb_loopback%u", dev_id);

	snprintf(d->sysfs_entry, MAX_SYSFS_PATH, "%s%s/",
		 t->sysfs_prefix, d->name);

	snprintf(d->debugfs_entry, MAX_SYSFS_PATH, "%sraw_latency_%s",
		 t->debugfs_prefix, d->name);

Fix this by separating the maximum path length from the maximum prefix
length and reducing the latter enough to fit the generated strings.

Note that we also need to reduce the device-name buffer size as GCC
isn't smart enough to figure out that we ever only used MAX_STR_LEN
bytes of it.

Fixes: 6b0658f6 ("greybus: tools: Add tools directory to greybus repo and add loopback")
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20200312110151.22028-4-johan@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Newer GCC warns about a possible truncation of a generated sysfs path
name as we're concatenating a directory path with a file name and
placing the result in a buffer that is half the size of the maximum
length of the directory path (which is user controlled).

loopback_test.c: In function 'open_poll_files':
loopback_test.c:651:31: warning: '%s' directive output may be truncated writing up to 511 bytes into a region of size 255 [-Wformat-truncation=]
  651 |   snprintf(buf, sizeof(buf), "%s%s", dev->sysfs_entry, "iteration_count");
      |                               ^~
loopback_test.c:651:3: note: 'snprintf' output between 16 and 527 bytes into a destination of size 255
  651 |   snprintf(buf, sizeof(buf), "%s%s", dev->sysfs_entry, "iteration_count");
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Fix this by making sure the buffer is large enough the concatenated
strings.

Fixes: 6b0658f6 ("greybus: tools: Add tools directory to greybus repo and add loopback")
Fixes: 9250c0ee ("greybus: Loopback_test: use poll instead of inotify")
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20200312110151.22028-3-johan@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

A scripted conversion from userland POLL* to kernel EPOLL* constants
mistakingly replaced the poll flags in the loopback_test tool, which
therefore no longer builds.

Fixes: a9a08845 ("vfs: do bulk POLL* -> EPOLL* replacement")
Cc: stable <stable@vger.kernel.org>     # 4.16
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20200312110151.22028-2-johan@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Access to result of ieee80211_bss_get_ie() is protected by RCU. In other
hand, function hif_join() can sleep and cannot be called with RCU
locked.

Provide a copy of "ssidie" to hif_join() to solve this behavior.

Fixes: 9ced9b59 ("staging: wfx: simplify hif_join()")
Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200310101356.182818-6-Jerome.Pouiller@silabs.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Access to sta->ht_cap is protected by RCU. However,
hif_set_association_mode() may sleep, so it can't be called in RCU.

This patch fix this behavior by handling sta and its RCU directly from
function hif_set_association_mode().
Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Fixes: d0014901 ("staging: wfx: fix RCU usage")
Link: https://lore.kernel.org/r/20200310101356.182818-5-Jerome.Pouiller@silabs.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Removing station while some traffic is in progress may happen.
Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200310101356.182818-4-Jerome.Pouiller@silabs.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Obviously introduced by mistake.

Fixes: 09779276 ("staging: wfx: simplify hif_start() usage")
Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200310101356.182818-3-Jerome.Pouiller@silabs.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

After hif_shutdown(), communication with the chip is no more possible.
It the only request that never reply. Therefore, hif_cmd.lock is never
unlocked. hif_shutdown() unlock itself hif_cmd.lock to avoid a potential
warning during disposal of device. hif_cmd.key_renew_lock should also
been unlocked for the same reason.
Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200310101356.182818-2-Jerome.Pouiller@silabs.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

get_char was erroneously given the address of the pointer to the text
instead of the address of the text, thus leading to random crashes when
the user requests speaking a word while the current position is on a space
character and say_word_ctl is not enabled.

Reported-on: https://github.com/bytefire/speakup/issues/1Reported-by: Kirk Reiser <kirk@reisers.ca>
Reported-by: Janina Sajka <janina@rednote.net>
Reported-by: Alexandr Epaneshnikov <aarnaarn2@gmail.com>
Reported-by: Gregory Nowak <greg@gregn.net>
Reported-by: deedra waters <deedra@the-brannons.com>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Tested-by: Alexandr Epaneshnikov <aarnaarn2@gmail.com>
Tested-by: Gregory Nowak <greg@gregn.net>
Tested-by: Michael Taboada <michael@michaels.world>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200306003047.thijtmqrnayd3dmw@functionSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pa_laser_ping_cfg should be set in of_ping_match
instead of pa_ping_cfg.

Fixes: 7bb501f4 ("iio: ping: add parallax ping sensors")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Andreas Klinger <ak@it-klinger.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

SPS30 uses triggered buffer, but the dependency is not specified in the
Kconfig file.  Fix this by selecting IIO_BUFFER and IIO_TRIGGERED_BUFFER
config symbols.

Cc: stable@vger.kernel.org
Fixes: 232e0f6d ("iio: chemical: add support for Sensirion SPS30 sensor")
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

According to ST, the HID is for LIS2DH12.

Fixes: 3d56e198 ("iio: accel: st_accel: Add support for the SMO8840 ACPI id")
Signed-off-by: Wen-chien Jesse Sung <jesse.sung@canonical.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Vishay has published a new version of "Designing the VCNL4200 Into an
Application" application note in October 2019. The new version specifies
that there is +-20% of part to part tolerance. Although the application
note is related to vcnl4200, according to support the vcnl4040's "ASIC
is quite similar to that one for the VCNL4200".

So update the sampling periods (and comment), including the correct
sampling period for proximity. Both sampling periods are lower. Users
relying on the blocking behaviour of reading will get proximity
measurements much earlier.

Fixes: 5a441aad ("iio: light: vcnl4000 add support for the VCNL4040 proximity and light sensor")
Reviewed-by: Guido Günther <agx@sigxcpu.org>
Tested-by: Guido Günther <agx@sigxcpu.org>
Signed-off-by: Tomas Novotny <tomas@novotny.cz>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Vishay has published a new version of "Designing the VCNL4200 Into an
Application" application note in October 2019. The new version specifies
that there is +-20% of part to part tolerance. This explains the drift
seen during experiments. The proximity pulse width is also changed from
32us to 30us. According to the support, the tolerance also applies to
ambient light.

So update the sampling periods. As the reading is blocking, current
users may notice slightly longer response time.

Fixes: be38866f ("iio: vcnl4000: add support for VCNL4200")
Reviewed-by: Guido Günther <agx@sigxcpu.org>
Signed-off-by: Tomas Novotny <tomas@novotny.cz>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Data stored in the iio-buffer is BE and this
should be specified in the iio_chan_spec struct.

Fixes: f4f55ce3 ("iio:adxl372: Add FIFO and interrupts support")
Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Pull btrfs fixes from David Sterba:
 "These are fixes that were found during testing with help of error
  injection, plus some other stable material.

  There's a fixup to patch added to rc1 causing locking in wrong context
  warnings, tests found one more deadlock scenario. The patches are
  tagged for stable, two of them now in the queue but we'd like all
  three released at the same time.

  I'm not happy about fixes to fixes in such a fast succession during
  rcs, but I hope we found all the fallouts of commit 28553fa9
  ('Btrfs: fix race between shrinking truncate and fiemap')"

* tag 'for-5.6-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix deadlock during fast fsync when logging prealloc extents beyond eof
  Btrfs: fix btrfs_wait_ordered_range() so that it waits for all ordered extents
  btrfs: fix bytes_may_use underflow in prealloc error condtition
  btrfs: handle logged extent failure properly
  btrfs: do not check delayed items are empty for single transaction cleanup
  btrfs: reset fs_root to NULL on error in open_ctree
  btrfs: destroy qgroup extent records on transaction abort

Pull ext4 fixes from Ted Ts'o:
 "More miscellaneous ext4 bug fixes (all stable fodder)"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix mount failure with quota configured as module
  jbd2: fix ocfs2 corrupt when clearing block group bits
  ext4: fix race between writepages and enabling EXT4_EXTENTS_FL
  ext4: rename s_journal_flag_rwsem to s_writepages_rwsem
  ext4: fix potential race between s_flex_groups online resizing and access
  ext4: fix potential race between s_group_info online resizing and access
  ext4: fix potential race between online resizing and write operations
  ext4: add cond_resched() to __ext4_find_entry()
  ext4: fix a data race in EXT4_I(inode)->i_disksize

Pull csky updates from Guo Ren:
 "Sorry, I missed 5.6-rc1 merge window, but in this pull request the
  most are the fixes and the rests are between fixes and features. The
  only outside modification is the MAINTAINERS file update with our
  mailing list.

   - cache flush implementation fixes

   - ftrace modify panic fix

   - CONFIG_SMP boot problem fix

   - fix pt_regs saving for atomic.S

   - fix fixaddr_init without highmem.

   - fix stack protector support

   - fix fake Tightly-Coupled Memory code compile and use

   - fix some typos and coding convention"

* tag 'csky-for-linus-5.6-rc3' of git://github.com/c-sky/csky-linux: (23 commits)
  csky: Replace <linux/clk-provider.h> by <linux/of_clk.h>
  csky: Implement copy_thread_tls
  csky: Add PCI support
  csky: Minimize defconfig to support buildroot config.fragment
  csky: Add setup_initrd check code
  csky: Cleanup old Kconfig options
  arch/csky: fix some Kconfig typos
  csky: Fixup compile warning for three unimplemented syscalls
  csky: Remove unused cache implementation
  csky: Fixup ftrace modify panic
  csky: Add flush_icache_mm to defer flush icache all
  csky: Optimize abiv2 copy_to_user_page with VM_EXEC
  csky: Enable defer flush_dcache_page for abiv2 cpus (807/810/860)
  csky: Remove unnecessary flush_icache_* implementation
  csky: Support icache flush without specific instructions
  csky/Kconfig: Add Kconfig.platforms to support some drivers
  csky/smp: Fixup boot failed when CONFIG_SMP
  csky: Set regs->usp to kernel sp, when the exception is from kernel
  csky/mm: Fixup export invalid_pte_table symbol
  csky: Separate fixaddr_init from highmem
  ...

The C-Sky platform code is not a clock provider, and just needs to call
of_clk_init().

Hence it can include <linux/of_clk.h> instead of <linux/clk-provider.h>.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Pull RAS fixes from Thomas Gleixner:
 "Two fixes for the AMD MCE driver:

   - Populate the per CPU MCA bank descriptor pointer only after it has
     been completely set up to prevent a use-after-free in case that one
     of the subsequent initialization step fails

   - Implement a proper release function for the sysfs entries of MCA
     threshold controls instead of freeing the memory right in the CPU
     teardown code, which leads to another use-after-free when the
     associated sysfs file is opened and accessed"

* tag 'ras-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce/amd: Fix kobject lifetime
  x86/mce/amd: Publish the bank pointer only after setup has succeeded

Pull irq fixes from Thomas Gleixner:
 "Two fixes for the irq core code which are follow ups to the recent MSI
  fixes:

   - The WARN_ON which was put into the MSI setaffinity callback for
     paranoia reasons actually triggered via a callchain which escaped
     when all the possible ways to reach that code were analyzed.

     The proc/irq/$N/*affinity interfaces have a quirk which came in
     when ALPHA moved to the generic interface: In case that the written
     affinity mask does not contain any online CPU it calls into ALPHAs
     magic auto affinity setting code.

     A few years later this mechanism was also made available to x86 for
     no good reasons and in a way which circumvents all sanity checks
     for interrupts which cannot have their affinity set from process
     context on X86 due to the way the X86 interrupt delivery works.

     It would be possible to make this work properly, but there is no
     point in doing so. If the interrupt is not yet started then the
     affinity setting has no effect and if it is started already then it
     is already assigned to an online CPU so there is no point to
     randomly move it to some other CPU. Just return EINVAL as the code
     has done before that change forever.

   - The new MSI quirk bit in the irq domain flags turned out to be
     already occupied, which escaped the author and the reviewers
     because the already in use bits were 0,6,2,3,4,5 listed in that
     order.

     That bit 6 was simply overlooked because the ordering was straight
     forward linear otherwise. So the new bit ended up being a
     duplicate.

     Fix it up by switching the oddball 6 to the obvious 1"

* tag 'irq-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/irqdomain: Make sure all irq domain flags are distinct
  genirq/proc: Reject invalid affinity masks (again)

Pull x86 fixes from Thomas Gleixner:
 "Two fixes for x86:

   - Remove the __force_oder definiton from the kaslr boot code as it is
     already defined in the page table code which makes GCC 10 builds
     fail because it changed the default to -fno-common.

   - Address the AMD erratum 1054 concerning the IRPERF capability and
     enable the Instructions Retired fixed counter on machines which are
     not affected by the erratum"

* tag 'x86-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu/amd: Enable the fixed Instructions Retired counter IRPERF
  x86/boot/compressed: Don't declare __force_order in kaslr_64.c

Pull zonefs fix from Damien Le Moal:
 "A single patch fixing typos in the documentation file"

* tag 'zonefs-5.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs:
  zonefs: fix documentation typos etc.

Pull io_uring fixes from Jens Axboe:
 "Here's a small collection of fixes that were queued up:

   - Remove unnecessary NULL check (Dan)

   - Missing io_req_cancelled() call in fallocate (Pavel)

   - Put the cleanup check for aux data in the right spot (Pavel)

   - Two fixes for SQPOLL (Stefano, Xiaoguang)"

* tag 'io_uring-5.6-2020-02-22' of git://git.kernel.dk/linux-block:
  io_uring: fix __io_iopoll_check deadlock in io_sq_thread
  io_uring: prevent sq_thread from spinning when it should stop
  io_uring: fix use-after-free by io_cleanup_req()
  io_uring: remove unnecessary NULL checks
  io_uring: add missing io_req_cancelled()

Pull block fixes from Jens Axboe:
 "Just a set of NVMe fixes via Keith"

* tag 'block-5.6-2020-02-22' of git://git.kernel.dk/linux-block:
  nvme-multipath: Fix memory leak with ana_log_buf
  nvme: Fix uninitialized-variable warning
  nvme-pci: Use single IRQ vector for old Apple models
  nvme/pci: Add sleep quirk for Samsung and Toshiba drives

Pull SCSI fixes from James Bottomley:
 "Four non-core fixes.

  Two are reverts of target fixes which turned out to have unwanted side
  effects, one is a revert of an RDMA fix with the same problem and the
  final one fixes an incorrect warning about memory allocation failures
  in megaraid_sas (the driver actually reduces the allocation size until
  it succeeds)"
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: Revert "target: iscsi: Wait for all commands to finish before freeing a session"
  scsi: Revert "RDMA/isert: Fix a recently introduced regression related to logout"
  scsi: megaraid_sas: silence a warning
  scsi: Revert "target/core: Inline transport_lun_remove_cmd()"

Merge tag 'hwmon-for-v5.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:

 - Fix crash in w83627ehf driver seen with W83627DHG-P

 - Fix lockdep splat in acpi_power_meter driver

 - Fix xdpe12284 documentation Sphinx warnings

* tag 'hwmon-for-v5.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (w83627ehf) Fix crash seen with W83627DHG-P
  hwmon: (acpi_power_meter) Fix lockdep splat
  Documentation/hwmon: fix xdpe12284 Sphinx warnings

Pull devicetree fixes deom Rob Herring:
 "A handful of fixes in DT bindings for MDIO bus, Allwinner CSI, OMAP
  HSMMC, and Tegra124 EMC"

* tag 'devicetree-fixes-for-5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  dt-bindings: media: csi: Fix clocks description
  dt-bindings: media: csi: Add interconnects properties
  dt-bindings: net: mdio: remove compatible string from example
  dt-bindings: memory-controller: Update example for Tegra124 EMC
  dt-bindings: mmc: omap-hsmmc: Fix SDIO interrupt

Pull s390 fixes from Vasily Gorbik:

 - Remove ieee_emulation_warnings sysctl which is a dead code.

 - Avoid triggering rebuild of the kernel during make install.

 - Enable protected virtualization guest support in default configs.

 - Fix cio_ignore seq_file .next function to increase position index.
   And use kobj_to_dev instead of container_of in cio code.

 - Fix storage block address lists to contain absolute addresses in qdio
   code.

 - Few clang warnings and spelling fixes.

* tag 's390-5.6-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/qdio: fill SBALEs with absolute addresses
  s390/qdio: fill SL with absolute addresses
  s390: remove obsolete ieee_emulation_warnings
  s390: make 'install' not depend on vmlinux
  s390/kaslr: Fix casts in get_random
  s390/mm: Explicitly compare PAGE_DEFAULT_KEY against zero in storage_key_init_range
  s390/pkey/zcrypt: spelling s/crytp/crypt/
  s390/cio: use kobj_to_dev() API
  s390/defconfig: enable CONFIG_PROTECTED_VIRTUALIZATION_GUEST
  s390/cio: cio_ignore_proc_seq_next should increase position index

Since commit a3a0e43f ("io_uring: don't enter poll loop if we have
CQEs pending"), if we already events pending, we won't enter poll loop.
In case SETUP_IOPOLL and SETUP_SQPOLL are both enabled, if app has
been terminated and don't reap pending events which are already in cq
ring, and there are some reqs in poll_list, io_sq_thread will enter
__io_iopoll_check(), and find pending events, then return, this loop
will never have a chance to exit.

I have seen this issue in fio stress tests, to fix this issue, let
io_sq_thread call io_iopoll_getevents() with argument 'min' being zero,
and remove __io_iopoll_check().

Fixes: a3a0e43f ("io_uring: don't enter poll loop if we have CQEs pending")
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

When CONFIG_QFMT_V2 is configured as a module, the test in
ext4_feature_set_ok() fails and so mount of filesystems with quota or
project features fails. Fix the test to use IS_ENABLED macro which
works properly even for modules.

Link: https://lore.kernel.org/r/20200221100835.9332-1-jack@suse.cz
Fixes: d65d87a0 ("ext4: improve explanation of a mount failure caused by a misconfigured kernel")
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org

I found a NULL pointer dereference in ocfs2_block_group_clear_bits().
The running environment:
	kernel version: 4.19
	A cluster with two nodes, 5 luns mounted on two nodes, and do some
	file operations like dd/fallocate/truncate/rm on every lun with storage
	network disconnection.

The fallocate operation on dm-23-45 caused an null pointer dereference.

The information of NULL pointer dereference as follows:
	[577992.878282] JBD2: Error -5 detected when updating journal superblock for dm-23-45.
	[577992.878290] Aborting journal on device dm-23-45.
	...
	[577992.890778] JBD2: Error -5 detected when updating journal superblock for dm-24-46.
	[577992.890908] __journal_remove_journal_head: freeing b_committed_data
	[577992.890916] (fallocate,88392,52):ocfs2_extend_trans:474 ERROR: status = -30
	[577992.890918] __journal_remove_journal_head: freeing b_committed_data
	[577992.890920] (fallocate,88392,52):ocfs2_rotate_tree_right:2500 ERROR: status = -30
	[577992.890922] __journal_remove_journal_head: freeing b_committed_data
	[577992.890924] (fallocate,88392,52):ocfs2_do_insert_extent:4382 ERROR: status = -30
	[577992.890928] (fallocate,88392,52):ocfs2_insert_extent:4842 ERROR: status = -30
	[577992.890928] __journal_remove_journal_head: freeing b_committed_data
	[577992.890930] (fallocate,88392,52):ocfs2_add_clusters_in_btree:4947 ERROR: status = -30
	[577992.890933] __journal_remove_journal_head: freeing b_committed_data
	[577992.890939] __journal_remove_journal_head: freeing b_committed_data
	[577992.890949] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
	[577992.890950] Mem abort info:
	[577992.890951]   ESR = 0x96000004
	[577992.890952]   Exception class = DABT (current EL), IL = 32 bits
	[577992.890952]   SET = 0, FnV = 0
	[577992.890953]   EA = 0, S1PTW = 0
	[577992.890954] Data abort info:
	[577992.890955]   ISV = 0, ISS = 0x00000004
	[577992.890956]   CM = 0, WnR = 0
	[577992.890958] user pgtable: 4k pages, 48-bit VAs, pgdp = 00000000f8da07a9
	[577992.890960] [0000000000000020] pgd=0000000000000000
	[577992.890964] Internal error: Oops: 96000004 [#1] SMP
	[577992.890965] Process fallocate (pid: 88392, stack limit = 0x00000000013db2fd)
	[577992.890968] CPU: 52 PID: 88392 Comm: fallocate Kdump: loaded Tainted: G        W  OE     4.19.36 #1
	[577992.890969] Hardware name: Huawei TaiShan 2280 V2/BC82AMDD, BIOS 0.98 08/25/2019
	[577992.890971] pstate: 60400009 (nZCv daif +PAN -UAO)
	[577992.891054] pc : _ocfs2_free_suballoc_bits+0x63c/0x968 [ocfs2]
	[577992.891082] lr : _ocfs2_free_suballoc_bits+0x618/0x968 [ocfs2]
	[577992.891084] sp : ffff0000c8e2b810
	[577992.891085] x29: ffff0000c8e2b820 x28: 0000000000000000
	[577992.891087] x27: 00000000000006f3 x26: ffffa07957b02e70
	[577992.891089] x25: ffff807c59d50000 x24: 00000000000006f2
	[577992.891091] x23: 0000000000000001 x22: ffff807bd39abc30
	[577992.891093] x21: ffff0000811d9000 x20: ffffa07535d6a000
	[577992.891097] x19: ffff000001681638 x18: ffffffffffffffff
	[577992.891098] x17: 0000000000000000 x16: ffff000080a03df0
	[577992.891100] x15: ffff0000811d9708 x14: 203d207375746174
	[577992.891101] x13: 73203a524f525245 x12: 20373439343a6565
	[577992.891103] x11: 0000000000000038 x10: 0101010101010101
	[577992.891106] x9 : ffffa07c68a85d70 x8 : 7f7f7f7f7f7f7f7f
	[577992.891109] x7 : 0000000000000000 x6 : 0000000000000080
	[577992.891110] x5 : 0000000000000000 x4 : 0000000000000002
	[577992.891112] x3 : ffff000001713390 x2 : 2ff90f88b1c22f00
	[577992.891114] x1 : ffff807bd39abc30 x0 : 0000000000000000
	[577992.891116] Call trace:
	[577992.891139]  _ocfs2_free_suballoc_bits+0x63c/0x968 [ocfs2]
	[577992.891162]  _ocfs2_free_clusters+0x100/0x290 [ocfs2]
	[577992.891185]  ocfs2_free_clusters+0x50/0x68 [ocfs2]
	[577992.891206]  ocfs2_add_clusters_in_btree+0x198/0x5e0 [ocfs2]
	[577992.891227]  ocfs2_add_inode_data+0x94/0xc8 [ocfs2]
	[577992.891248]  ocfs2_extend_allocation+0x1bc/0x7a8 [ocfs2]
	[577992.891269]  ocfs2_allocate_extents+0x14c/0x338 [ocfs2]
	[577992.891290]  __ocfs2_change_file_space+0x3f8/0x610 [ocfs2]
	[577992.891309]  ocfs2_fallocate+0xe4/0x128 [ocfs2]
	[577992.891316]  vfs_fallocate+0x11c/0x250
	[577992.891317]  ksys_fallocate+0x54/0x88
	[577992.891319]  __arm64_sys_fallocate+0x28/0x38
	[577992.891323]  el0_svc_common+0x78/0x130
	[577992.891325]  el0_svc_handler+0x38/0x78
	[577992.891327]  el0_svc+0x8/0xc

My analysis process as follows:
ocfs2_fallocate
  __ocfs2_change_file_space
    ocfs2_allocate_extents
      ocfs2_extend_allocation
        ocfs2_add_inode_data
          ocfs2_add_clusters_in_btree
            ocfs2_insert_extent
              ocfs2_do_insert_extent
                ocfs2_rotate_tree_right
                  ocfs2_extend_rotate_transaction
                    ocfs2_extend_trans
                      jbd2_journal_restart
                        jbd2__journal_restart
                          /* handle->h_transaction is NULL,
                           * is_handle_aborted(handle) is true
                           */
                          handle->h_transaction = NULL;
                          start_this_handle
                            return -EROFS;
            ocfs2_free_clusters
              _ocfs2_free_clusters
                _ocfs2_free_suballoc_bits
                  ocfs2_block_group_clear_bits
                    ocfs2_journal_access_gd
                      __ocfs2_journal_access
                        jbd2_journal_get_undo_access
                          /* I think jbd2_write_access_granted() will
                           * return true, because do_get_write_access()
                           * will return -EROFS.
                           */
                          if (jbd2_write_access_granted(...)) return 0;
                          do_get_write_access
                            /* handle->h_transaction is NULL, it will
                             * return -EROFS here, so do_get_write_access()
                             * was not called.
                             */
                            if (is_handle_aborted(handle)) return -EROFS;
                    /* bh2jh(group_bh) is NULL, caused NULL
                       pointer dereference */
                    undo_bg = (struct ocfs2_group_desc *)
                                bh2jh(group_bh)->b_committed_data;

If handle->h_transaction == NULL, then jbd2_write_access_granted()
does not really guarantee that journal_head will stay around,
not even speaking of its b_committed_data. The bh2jh(group_bh)
can be removed after ocfs2_journal_access_gd() and before call
"bh2jh(group_bh)->b_committed_data". So, we should move
is_handle_aborted() check from do_get_write_access() into
jbd2_journal_get_undo_access() and jbd2_journal_get_write_access()
before the call to jbd2_write_access_granted().

Link: https://lore.kernel.org/r/f72a623f-b3f1-381a-d91d-d22a1c83a336@huawei.comSigned-off-by: Yan Wang <wangyan122@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org

If EXT4_EXTENTS_FL is set on an inode while ext4_writepages() is running
on it, the following warning in ext4_add_complete_io() can be hit:

WARNING: CPU: 1 PID: 0 at fs/ext4/page-io.c:234 ext4_put_io_end_defer+0xf0/0x120

Here's a minimal reproducer (not 100% reliable) (root isn't required):

        while true; do
                sync
        done &
        while true; do
                rm -f file
                touch file
                chattr -e file
                echo X >> file
                chattr +e file
        done

The problem is that in ext4_writepages(), ext4_should_dioread_nolock()
(which only returns true on extent-based files) is checked once to set
the number of reserved journal credits, and also again later to select
the flags for ext4_map_blocks() and copy the reserved journal handle to
ext4_io_end::handle.  But if EXT4_EXTENTS_FL is being concurrently set,
the first check can see dioread_nolock disabled while the later one can
see it enabled, causing the reserved handle to unexpectedly be NULL.

Since changing EXT4_EXTENTS_FL is uncommon, and there may be other races
related to doing so as well, fix this by synchronizing changing
EXT4_EXTENTS_FL with ext4_writepages() via the existing
s_writepages_rwsem (previously called s_journal_flag_rwsem).

This was originally reported by syzbot without a reproducer at
https://syzkaller.appspot.com/bug?extid=2202a584a00fffd19fbf,
but now that dioread_nolock is the default I also started seeing this
when running syzkaller locally.

Link: https://lore.kernel.org/r/20200219183047.47417-3-ebiggers@kernel.org
Reported-by: syzbot+2202a584a00fffd19fbf@syzkaller.appspotmail.com
Fixes: 6b523df4 ("ext4: use transaction reservation for extent conversion in ext4_end_io")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org

In preparation for making s_journal_flag_rwsem synchronize
ext4_writepages() with changes to both the EXTENTS and JOURNAL_DATA
flags (rather than just JOURNAL_DATA as it does currently), rename it to
s_writepages_rwsem.

Link: https://lore.kernel.org/r/20200219183047.47417-2-ebiggers@kernel.orgSigned-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org

During an online resize an array of s_flex_groups structures gets replaced
so it can get enlarged. If there is a concurrent access to the array and
this memory has been reused then this can lead to an invalid memory access.

The s_flex_group array has been converted into an array of pointers rather
than an array of structures. This is to ensure that the information
contained in the structures cannot get out of sync during a resize due to
an accessor updating the value in the old structure after it has been
copied but before the array pointer is updated. Since the structures them-
selves are no longer copied but only the pointers to them this case is
mitigated.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=206443
Link: https://lore.kernel.org/r/20200221053458.730016-4-tytso@mit.eduSigned-off-by: Suraj Jitindar Singh <surajjs@amazon.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org

Pull xen fixes from Juergen Gross:
 "Two small fixes for Xen:

   - a fix to avoid warnings with new gcc

   - a fix for incorrectly disabled interrupts when calling
     _cond_resched()"

* tag 'for-linus-5.6-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: Enable interrupts when calling _cond_resched()
  x86/xen: Distribute switch variables for initialization

Pull arm64 fixes from Will Deacon:
 "It's all straightforward apart from the changes to mmap()/mremap() in
  relation to their handling of address arguments from userspace with
  non-zero tag bits in the upper byte.

  The change to brk() is necessary to fix a nasty user-visible
  regression in malloc(), but we tightened up mmap() and mremap() at the
  same time because they also allow the user to create virtual aliases
  by accident. It's much less likely than brk() to matter in practice,
  but enforcing the principle of "don't permit the creation of mappings
  using tagged addresses" leads to a straightforward ABI without having
  to worry about the "but what if a crazy program did foo?" aspect of
  things.

  Summary:

   - Fix regression in malloc() caused by ignored address tags in brk()

   - Add missing brackets around argument to untagged_addr() macro

   - Fix clang build when using binutils assembler

   - Fix silly typo in virtual memory map documentation"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  mm: Avoid creating virtual address aliases in brk()/mmap()/mremap()
  docs: arm64: fix trivial spelling enought to enough in memory.rst
  arm64: memory: Add missing brackets to untagged_addr() macro
  arm64: lse: Fix LSE atomics with LLVM