linux-stable.git/drivers, branch v4.4.249

PCI: Fix pci_slot_release() NULL pointer dereference

2020-12-29T12:42:46+00:00

commit 4684709bf81a2d98152ed6b610e3d5c403f9bced upstream.

If kobject_init_and_add() fails, pci_slot_release() is called to delete
slot->list from parent->slots.  But slot->list hasn't been initialized
yet, so we dereference a NULL pointer:

  Unable to handle kernel NULL pointer dereference at virtual address
00000000
  ...
  CPU: 10 PID: 1 Comm: swapper/0 Not tainted 4.4.240 #197
  task: ffffeb398a45ef10 task.stack: ffffeb398a470000
  PC is at __list_del_entry_valid+0x5c/0xb0
  LR is at pci_slot_release+0x84/0xe4
  ...
  __list_del_entry_valid+0x5c/0xb0
  pci_slot_release+0x84/0xe4
  kobject_put+0x184/0x1c4
  pci_create_slot+0x17c/0x1b4
  __pci_hp_initialize+0x68/0xa4
  pciehp_probe+0x1a4/0x2fc
  pcie_port_probe_service+0x58/0x84
  driver_probe_device+0x320/0x470

Initialize slot->list before calling kobject_init_and_add() to avoid this.

Fixes: 8a94644b440e ("PCI: Fix pci_create_slot() reference count leak")
Link: https://lore.kernel.org/r/1606876422-117457-1-git-send-email-zhongjubin@huawei.com
Signed-off-by: Jubin Zhong 
Signed-off-by: Bjorn Helgaas 
Cc: stable@vger.kernel.org	# v5.9+
Signed-off-by: Greg Kroah-Hartman

xenbus/xenbus_backend: Disallow pending watch messages

2020-12-29T12:42:45+00:00

commit 9996bd494794a2fe393e97e7a982388c6249aa76 upstream.

'xenbus_backend' watches 'state' of devices, which is writable by
guests.  Hence, if guests intensively updates it, dom0 will have lots of
pending events that exhausting memory of dom0.  In other words, guests
can trigger dom0 memory pressure.  This is known as XSA-349.  However,
the watch callback of it, 'frontend_changed()', reads only 'state', so
doesn't need to have the pending events.

To avoid the problem, this commit disallows pending watch messages for
'xenbus_backend' using the 'will_handle()' watch callback.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park 
Reported-by: Michael Kurth 
Reported-by: Pawel Wieczorkiewicz 
Reviewed-by: Juergen Gross 
Signed-off-by: Juergen Gross 
Signed-off-by: Greg Kroah-Hartman

xen/xenbus: Count pending messages for each watch

2020-12-29T12:42:45+00:00

commit 3dc86ca6b4c8cfcba9da7996189d1b5a358a94fc upstream.

This commit adds a counter of pending messages for each watch in the
struct.  It is used to skip unnecessary pending messages lookup in
'unregister_xenbus_watch()'.  It could also be used in 'will_handle'
callback.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park 
Reported-by: Michael Kurth 
Reported-by: Pawel Wieczorkiewicz 
Reviewed-by: Juergen Gross 
Signed-off-by: Juergen Gross 
Signed-off-by: Greg Kroah-Hartman

xen/xenbus/xen_bus_type: Support will_handle watch callback

2020-12-29T12:42:45+00:00

commit be987200fbaceaef340872841d4f7af2c5ee8dc3 upstream.

This commit adds support of the 'will_handle' watch callback for
'xen_bus_type' users.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park 
Reported-by: Michael Kurth 
Reported-by: Pawel Wieczorkiewicz 
Reviewed-by: Juergen Gross 
Signed-off-by: Juergen Gross 
Signed-off-by: Greg Kroah-Hartman

xen/xenbus: Add 'will_handle' callback support in xenbus_watch_path()

2020-12-29T12:42:45+00:00

commit 2e85d32b1c865bec703ce0c962221a5e955c52c2 upstream.

Some code does not directly make 'xenbus_watch' object and call
'register_xenbus_watch()' but use 'xenbus_watch_path()' instead.  This
commit adds support of 'will_handle' callback in the
'xenbus_watch_path()' and it's wrapper, 'xenbus_watch_pathfmt()'.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park 
Reported-by: Michael Kurth 
Reported-by: Pawel Wieczorkiewicz 
Reviewed-by: Juergen Gross 
Signed-off-by: Juergen Gross 
Signed-off-by: Greg Kroah-Hartman

xen/xenbus: Allow watches discard events before queueing

2020-12-29T12:42:45+00:00

commit fed1755b118147721f2c87b37b9d66e62c39b668 upstream.

If handling logics of watch events are slower than the events enqueue
logic and the events can be created from the guests, the guests could
trigger memory pressure by intensively inducing the events, because it
will create a huge number of pending events that exhausting the memory.

Fortunately, some watch events could be ignored, depending on its
handler callback.  For example, if the callback has interest in only one
single path, the watch wouldn't want multiple pending events.  Or, some
watches could ignore events to same path.

To let such watches to volutarily help avoiding the memory pressure
situation, this commit introduces new watch callback, 'will_handle'.  If
it is not NULL, it will be called for each new event just before
enqueuing it.  Then, if the callback returns false, the event will be
discarded.  No watch is using the callback for now, though.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park 
Reported-by: Michael Kurth 
Reported-by: Pawel Wieczorkiewicz 
Reviewed-by: Juergen Gross 
Signed-off-by: Juergen Gross 
Signed-off-by: Greg Kroah-Hartman

iio:pressure:mpl3115: Force alignment of buffer

2020-12-29T12:42:45+00:00

commit 198cf32f0503d2ad60d320b95ef6fb8243db857f upstream.

Whilst this is another case of the issue Lars reported with
an array of elements of smaller than 8 bytes being passed
to iio_push_to_buffers_with_timestamp(), the solution here is
a bit different from the other cases and relies on __aligned
working on the stack (true since 4.6?)

This one is unusual.  We have to do an explicit memset() each time
as we are reading 3 bytes into a potential 4 byte channel which
may sometimes be a 2 byte channel depending on what is enabled.
As such, moving the buffer to the heap in the iio_priv structure
doesn't save us much.  We can't use a nice explicit structure
on the stack either as the data channels have different storage
sizes and are all separately controlled.

Fixes: cc26ad455f57 ("iio: Add Freescale MPL3115A2 pressure / temperature sensor driver")
Reported-by: Lars-Peter Clausen 
Signed-off-by: Jonathan Cameron 
Reviewed-by: Andy Shevchenko 
Reviewed-by: Alexandru Ardelean 
Cc: Peter Meerwald 
Cc: 
Link: https://lore.kernel.org/r/20200920112742.170751-7-jic23@kernel.org
Signed-off-by: Greg Kroah-Hartman

iio: adc: rockchip_saradc: fix missing clk_disable_unprepare() on error in rockchip_saradc_resume

2020-12-29T12:42:45+00:00

commit 560c6b914c6ec7d9d9a69fddbb5bf3bf71433e8b upstream.

Fix the missing clk_disable_unprepare() of info->pclk
before return from rockchip_saradc_resume in the error
handling case when fails to prepare and enable info->clk.

Suggested-by: Robin Murphy 
Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
Signed-off-by: Qinglang Miao 
Cc: 
Link: https://lore.kernel.org/r/20201103120743.110662-1-miaoqinglang@huawei.com
Signed-off-by: Jonathan Cameron 
Signed-off-by: Greg Kroah-Hartman

mtd: parser: cmdline: Fix parsing of part-names with colons

2020-12-29T12:42:45+00:00

commit 639a82434f16a6df0ce0e7c8595976f1293940fd upstream.

Some devices (especially QCA ones) are already using hardcoded partition
names with colons in it. The OpenMesh A62 for example provides following
mtd relevant information via cmdline:

  root=31:11 mtdparts=spi0.0:256k(0:SBL1),128k(0:MIBIB),384k(0:QSEE),64k(0:CDT),64k(0:DDRPARAMS),64k(0:APPSBLENV),512k(0:APPSBL),64k(0:ART),64k(custom),64k(0:KEYS),0x002b0000(kernel),0x00c80000(rootfs),15552k(inactive) rootfsname=rootfs rootwait

The change to split only on the last colon between mtd-id and partitions
will cause newpart to see following string for the first partition:

  KEYS),0x002b0000(kernel),0x00c80000(rootfs),15552k(inactive)

Such a partition list cannot be parsed and thus the device fails to boot.

Avoid this behavior by making sure that the start of the first part-name
("(") will also be the last byte the mtd-id split algorithm is using for
its colon search.

Fixes: eb13fa022741 ("mtd: parser: cmdline: Support MTD names containing one or more colons")
Cc: stable@vger.kernel.org
Cc: Ron Minnich 
Signed-off-by: Sven Eckelmann 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20201124062506.185392-1-sven@narfation.org
Signed-off-by: Greg Kroah-Hartman

spi: rb4xx: Don't leak SPI master in probe error path

2020-12-29T12:42:45+00:00

commit a4729c3506c3eb1a6ca5c0289f4e7cafa4115065 upstream.

If the calls to devm_clk_get(), devm_spi_register_master() or
clk_prepare_enable() fail on probe of the Mikrotik RB4xx SPI driver,
the spi_master struct is erroneously not freed.

Fix by switching over to the new devm_spi_alloc_master() helper.

Fixes: 05aec357871f ("spi: Add SPI driver for Mikrotik RB4xx series boards")
Signed-off-by: Lukas Wunner 
Cc:  # v4.2+: 5e844cc37a5c: spi: Introduce device-managed SPI controller allocation
Cc:  # v4.2+
Cc: Bert Vermeulen 
Link: https://lore.kernel.org/r/369bf26d71927f60943b1d9d8f51810f00b0237d.1607286887.git.lukas@wunner.de
Signed-off-by: Mark Brown 
Signed-off-by: Greg Kroah-Hartman