linux-stable.git/drivers/rtc, branch v5.4.201

rtc: mt6397: check return value after calling platform_get_resource()

2022-06-14T16:11:53+00:00

[ Upstream commit d3b43eb505bffb8e4cdf6800c15660c001553fe6 ]

It will cause null-ptr-deref if platform_get_resource() returns NULL,
we need check the return value.

Fixes: fc2979118f3f ("rtc: mediatek: Add MT6397 RTC driver")
Signed-off-by: Yang Yingliang 
Reviewed-by: AngeloGioacchino Del Regno 
Signed-off-by: Alexandre Belloni 
Link: https://lore.kernel.org/r/20220505125043.1594771-1-yangyingliang@huawei.com
Signed-off-by: Sasha Levin

rtc: mc146818-lib: Fix the AltCentury for AMD platforms

2022-05-25T07:14:32+00:00

[ Upstream commit 3ae8fd41573af4fb3a490c9ed947fc936ba87190 ]

Setting the century forward has been failing on AMD platforms.
There was a previous attempt at fixing this for family 0x17 as part of
commit 7ad295d5196a ("rtc: Fix the AltCentury value on AMD/Hygon
platform") but this was later reverted due to some problems reported
that appeared to stem from an FW bug on a family 0x17 desktop system.

The same comments mentioned in the previous commit continue to apply
to the newer platforms as well.

```
MC146818 driver use function mc146818_set_time() to set register
RTC_FREQ_SELECT(RTC_REG_A)'s bit4-bit6 field which means divider stage
reset value on Intel platform to 0x7.

While AMD/Hygon RTC_REG_A(0Ah)'s bit4 is defined as DV0 [Reference]:
DV0 = 0 selects Bank 0, DV0 = 1 selects Bank 1. Bit5-bit6 is defined
as reserved.

DV0 is set to 1, it will select Bank 1, which will disable AltCentury
register(0x32) access. As UEFI pass acpi_gbl_FADT.century 0x32
(AltCentury), the CMOS write will be failed on code:
CMOS_WRITE(century, acpi_gbl_FADT.century).

Correct RTC_REG_A bank select bit(DV0) to 0 on AMD/Hygon CPUs, it will
enable AltCentury(0x32) register writing and finally setup century as
expected.
```

However in closer examination the change previously submitted was also
modifying bits 5 & 6 which are declared reserved in the AMD documentation.
So instead modify just the DV0 bank selection bit.

Being cognizant that there was a failure reported before, split the code
change out to a static function that can also be used for exclusions if
any regressions such as Mikhail's pop up again.

Cc: Jinke Fan 
Cc: Mikhail Gavrilov 
Link: https://lore.kernel.org/all/CABXGCsMLob0DC25JS8wwAYydnDoHBSoMh2_YLPfqm3TTvDE-Zw@mail.gmail.com/
Link: https://www.amd.com/system/files/TechDocs/51192_Bolton_FCH_RRG.pdf
Signed-off-by: Raul E Rangel 
Signed-off-by: Mario Limonciello 
Signed-off-by: Alexandre Belloni 
Link: https://lore.kernel.org/r/20220111225750.1699-1-mario.limonciello@amd.com
Signed-off-by: Sasha Levin

rtc: fix use-after-free on device removal

2022-05-25T07:14:31+00:00

[ Upstream commit c8fa17d9f08a448184f03d352145099b5beb618e ]

If the irqwork is still scheduled or running while the RTC device is
removed, a use-after-free occurs in rtc_timer_do_work().  Cleanup the
timerqueue and ensure the work is stopped to fix this.

 BUG: KASAN: use-after-free in mutex_lock+0x94/0x110
 Write of size 8 at addr ffffff801d846338 by task kworker/3:1/41

 Workqueue: events rtc_timer_do_work
 Call trace:
  mutex_lock+0x94/0x110
  rtc_timer_do_work+0xec/0x630
  process_one_work+0x5fc/0x1344
  ...

 Allocated by task 551:
  kmem_cache_alloc_trace+0x384/0x6e0
  devm_rtc_allocate_device+0xf0/0x574
  devm_rtc_device_register+0x2c/0x12c
  ...

 Freed by task 572:
  kfree+0x114/0x4d0
  rtc_device_release+0x64/0x80
  device_release+0x8c/0x1f4
  kobject_put+0x1c4/0x4b0
  put_device+0x20/0x30
  devm_rtc_release_device+0x1c/0x30
  devm_action_release+0x54/0x90
  release_nodes+0x124/0x310
  devres_release_group+0x170/0x240
  i2c_device_remove+0xd8/0x314
  ...

 Last potentially related work creation:
  insert_work+0x5c/0x330
  queue_work_on+0xcc/0x154
  rtc_set_time+0x188/0x5bc
  rtc_dev_ioctl+0x2ac/0xbd0
  ...

Signed-off-by: Vincent Whitchurch 
Signed-off-by: Alexandre Belloni 
Link: https://lore.kernel.org/r/20211210160951.7718-1-vincent.whitchurch@axis.com
Signed-off-by: Sasha Levin

rtc: wm8350: Handle error for wm8350_register_irq

2022-04-15T12:18:31+00:00

[ Upstream commit 43f0269b6b89c1eec4ef83c48035608f4dcdd886 ]

As the potential failure of the wm8350_register_irq(),
it should be better to check it and return error if fails.
Also, it need not free 'wm_rtc->rtc' since it will be freed
automatically.

Fixes: 077eaf5b40ec ("rtc: rtc-wm8350: add support for WM8350 RTC")
Signed-off-by: Jiasheng Jiang 
Acked-by: Charles Keepax 
Signed-off-by: Alexandre Belloni 
Link: https://lore.kernel.org/r/20220303085030.291793-1-jiasheng@iscas.ac.cn
Signed-off-by: Sasha Levin

rtc: check if __rtc_read_time was successful

2022-04-15T12:18:28+00:00

commit 915593a7a663b2ad08b895a5f3ba8b19d89d4ebf upstream.

Clang static analysis reports this issue
interface.c:810:8: warning: Passed-by-value struct
  argument contains uninitialized data
  now = rtc_tm_to_ktime(tm);
      ^~~~~~~~~~~~~~~~~~~

tm is set by a successful call to __rtc_read_time()
but its return status is not checked.  Check if
it was successful before setting the enabled flag.
Move the decl of err to function scope.

Fixes: 2b2f5ff00f63 ("rtc: interface: ignore expired timers when enqueuing new timers")
Signed-off-by: Tom Rix 
Signed-off-by: Alexandre Belloni 
Link: https://lore.kernel.org/r/20220326194236.2916310-1-trix@redhat.com
Signed-off-by: Greg Kroah-Hartman

rtc: cmos: Evaluate century appropriate

2022-02-08T17:24:34+00:00

commit ff164ae39b82ee483b24579c8e22a13a8ce5bd04 upstream.

There's limiting the year to 2069. When setting the rtc year to 2070,
reading it returns 1970. Evaluate century starting from 19 to count the
correct year.

$ sudo date -s 20700106
Mon 06 Jan 2070 12:00:00 AM CST
$ sudo hwclock -w
$ sudo hwclock -r
1970-01-06 12:00:49.604968+08:00

Fixes: 2a4daadd4d3e5071 ("rtc: cmos: ignore bogus century byte")

Signed-off-by: Riwen Lu 
Acked-by: Eric Wong 
Reviewed-by: Mateusz Jończyk 
Signed-off-by: Alexandre Belloni 
Link: https://lore.kernel.org/r/20220106084609.1223688-1-luriwen@kylinos.cn
Signed-off-by: Mateusz Jończyk  # preparation for stable
Signed-off-by: Greg Kroah-Hartman

rtc: pxa: fix null pointer dereference

2022-01-27T08:19:53+00:00

commit 34127b3632b21e5c391756e724b1198eb9917981 upstream.

With the latest stable kernel versions the rtc on the PXA based
Zaurus does not work, when booting I see the following kernel messages:

pxa-rtc pxa-rtc: failed to find rtc clock source
pxa-rtc pxa-rtc: Unable to init SA1100 RTC sub-device
pxa-rtc: probe of pxa-rtc failed with error -2
hctosys: unable to open rtc device (rtc0)

I think this is because commit f2997775b111 ("rtc: sa1100: fix possible
race condition") moved the allocation of the rtc_device struct out of
sa1100_rtc_init and into sa1100_rtc_probe. This means that pxa_rtc_probe
also needs to do allocation for the rtc_device struct, otherwise
sa1100_rtc_init will try to dereference a null pointer. This patch adds
that allocation by copying how sa1100_rtc_probe in
drivers/rtc/rtc-sa1100.c does it; after the IRQs are set up a managed
rtc_device is allocated.

I've tested this patch with `qemu-system-arm -machine akita` and with a
real Zaurus SL-C1000 applied to 4.19, 5.4, and 5.10.

Signed-off-by: Laurence de Bruxelles 
Fixes: f2997775b111 ("rtc: sa1100: fix possible race condition")
Signed-off-by: Alexandre Belloni 
Link: https://lore.kernel.org/r/20220101154149.12026-1-lfdebrux@gmail.com
Signed-off-by: Greg Kroah-Hartman

rtc: cmos: take rtc_lock while reading from CMOS

2022-01-27T08:19:27+00:00

commit 454f47ff464325223129b9b5b8d0b61946ec704d upstream.

Reading from the CMOS involves writing to the index register and then
reading from the data register. Therefore access to the CMOS has to be
serialized with rtc_lock. This invocation of CMOS_READ was not
serialized, which could cause trouble when other code is accessing CMOS
at the same time.

Use spin_lock_irq() like the rest of the function.

Nothing in kernel modifies the RTC_DM_BINARY bit, so there could be a
separate pair of spin_lock_irq() / spin_unlock_irq() before doing the
math.

Signed-off-by: Mateusz Jończyk 
Reviewed-by: Nobuhiro Iwamatsu 
Cc: Alessandro Zummo 
Cc: Alexandre Belloni 
Cc: stable@vger.kernel.org
Signed-off-by: Alexandre Belloni 
Link: https://lore.kernel.org/r/20211210200131.153887-2-mat.jonczyk@o2.pl
Signed-off-by: Greg Kroah-Hartman

rtc: rx8010: select REGMAP_I2C

2021-09-26T12:07:14+00:00

[ Upstream commit 0c45d3e24ef3d3d87c5e0077b8f38d1372af7176 ]

The rtc-rx8010 uses the I2C regmap but doesn't select it in Kconfig so
depending on the configuration the build may fail. Fix it.

Signed-off-by: Yu-Tung Chang 
Signed-off-by: Alexandre Belloni 
Link: https://lore.kernel.org/r/20210830052532.40356-1-mtwget@gmail.com
Signed-off-by: Sasha Levin

rtc: tps65910: Correct driver module alias

2021-09-22T10:26:19+00:00

commit 8d448fa0a8bb1c8d94eef7647edffe9ac81a281e upstream.

The TPS65910 RTC driver module doesn't auto-load because of the wrong
module alias that doesn't match the device name, fix it.

Cc: stable@vger.kernel.org
Reported-by: Anton Bambura 
Tested-by: Anton Bambura 
Signed-off-by: Dmitry Osipenko 
Signed-off-by: Alexandre Belloni 
Link: https://lore.kernel.org/r/20210808160030.8556-1-digetx@gmail.com
Signed-off-by: Greg Kroah-Hartman