linux-stable.git/drivers/staging, branch v5.4.293 Linux kernel stable tree comedi: jr3_pci: Fix synchronous deletion of timer 2025-05-02T05:39:29+00:00 Ian Abbott abbotti@mev.co.uk 2025-04-15T12:39:01+00:00 348adceb91b2adf888599d2cc5f95b68b09f7008 commit 44d9b3f584c59a606b521e7274e658d5b866c699 upstream. When `jr3_pci_detach()` is called during device removal, it calls `timer_delete_sync()` to stop the timer, but the timer expiry function always reschedules the timer, so the synchronization is ineffective. Call `timer_shutdown_sync()` instead. It does not matter that the timer expiry function pointer is cleared, because the device is being removed. Fixes: 07b509e6584a5 ("Staging: comedi: add jr3_pci driver") Cc: stable <stable@kernel.org> Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Link: https://lore.kernel.org/r/20250415123901.13483-1-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 44d9b3f584c59a606b521e7274e658d5b866c699 upstream.

When `jr3_pci_detach()` is called during device removal, it calls
`timer_delete_sync()` to stop the timer, but the timer expiry function
always reschedules the timer, so the synchronization is ineffective.

Call `timer_shutdown_sync()` instead.  It does not matter that the timer
expiry function pointer is cleared, because the device is being removed.

Fixes: 07b509e6584a5 ("Staging: comedi: add jr3_pci driver")
Cc: stable <stable@kernel.org>
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20250415123901.13483-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
staging: media: imx: fix OF node leak in imx_media_add_of_subdevs() 2025-03-13T11:42:58+00:00 Joe Hattori joe@pf.is.s.u-tokyo.ac.jp 2024-12-24T03:54:11+00:00 01ace0742cf6a480b9d70f97f8e7dc08754fba1c [ Upstream commit 094f5c315f756b19198e6c401aa821ac0e868750 ] imx_media_add_of_subdevs() calls of_parse_phandle() and passes the obtained node to imx_media_of_add_csi(). The passed node is used in v4l2_async_nf_add_fwnode(), which increments the refcount of the node. Therefore, while the current implementation only releases the node when imx_media_of_add_csi() fails, but should always release it. Call of_node_put() right after imx_media_of_add_csi(). Fixes: dee747f88167 ("media: imx: Don't register IPU subdevs/links if CSI port missing") Signed-off-by: Joe Hattori <joe@pf.is.s.u-tokyo.ac.jp> Reviewed-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 094f5c315f756b19198e6c401aa821ac0e868750 ]

imx_media_add_of_subdevs() calls of_parse_phandle() and passes the
obtained node to imx_media_of_add_csi(). The passed node is used in
v4l2_async_nf_add_fwnode(), which increments the refcount of the node.
Therefore, while the current implementation only releases the node when
imx_media_of_add_csi() fails, but should always release it. Call
of_node_put() right after imx_media_of_add_csi().

Fixes: dee747f88167 ("media: imx: Don't register IPU subdevs/links if CSI port missing")
Signed-off-by: Joe Hattori <joe@pf.is.s.u-tokyo.ac.jp>
Reviewed-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Sasha Levin <sashal@kernel.org>
staging: iio: ad9832: Correct phase range check 2025-02-01T17:18:46+00:00 Zicheng Qu quzicheng@huawei.com 2024-11-07T01:10:15+00:00 dd4f2d935d580f40f4ce74c80672254ea37b02d3 commit 4636e859ebe0011f41e35fa79bab585b8004e9a3 upstream. User Perspective: When a user sets the phase value, the ad9832_write_phase() is called. The phase register has a 12-bit resolution, so the valid range is 0 to 4095. If the phase offset value of 4096 is input, it effectively exactly equals 0 in the lower 12 bits, meaning no offset. Reasons for the Change: 1) Original Condition (phase > BIT(AD9832_PHASE_BITS)): This condition allows a phase value equal to 2^12, which is 4096. However, this value exceeds the valid 12-bit range, as the maximum valid phase value should be 4095. 2) Modified Condition (phase >= BIT(AD9832_PHASE_BITS)): Ensures that the phase value is within the valid range, preventing invalid datafrom being written. Impact on Subsequent Logic: st->data = cpu_to_be16(addr | phase): If the phase value is 2^12, i.e., 4096 (0001 0000 0000 0000), and addr is AD9832_REG_PHASE0 (1100 0000 0000 0000), then addr | phase results in 1101 0000 0000 0000, occupying DB12. According to the section of WRITING TO A PHASE REGISTER in the datasheet, the MSB 12 PHASE0 bits should be DB11. The original condition leads to incorrect DB12 usage, which contradicts the datasheet and could pose potential issues for future updates if DB12 is used in such related cases. Fixes: ea707584bac1 ("Staging: IIO: DDS: AD9832 / AD9835 driver") Cc: stable@vger.kernel.org Signed-off-by: Zicheng Qu <quzicheng@huawei.com> Link: https://patch.msgid.link/20241107011015.2472600-3-quzicheng@huawei.com Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 4636e859ebe0011f41e35fa79bab585b8004e9a3 upstream.

User Perspective:
When a user sets the phase value, the ad9832_write_phase() is called.
The phase register has a 12-bit resolution, so the valid range is 0 to
4095. If the phase offset value of 4096 is input, it effectively exactly
equals 0 in the lower 12 bits, meaning no offset.

Reasons for the Change:
1) Original Condition (phase > BIT(AD9832_PHASE_BITS)):
This condition allows a phase value equal to 2^12, which is 4096.
However, this value exceeds the valid 12-bit range, as the maximum valid
phase value should be 4095.
2) Modified Condition (phase >= BIT(AD9832_PHASE_BITS)):
Ensures that the phase value is within the valid range, preventing
invalid datafrom being written.

Impact on Subsequent Logic: st->data = cpu_to_be16(addr | phase):
If the phase value is 2^12, i.e., 4096 (0001 0000 0000 0000), and addr
is AD9832_REG_PHASE0 (1100 0000 0000 0000), then addr | phase results in
1101 0000 0000 0000, occupying DB12. According to the section of WRITING
TO A PHASE REGISTER in the datasheet, the MSB 12 PHASE0 bits should be
DB11. The original condition leads to incorrect DB12 usage, which
contradicts the datasheet and could pose potential issues for future
updates if DB12 is used in such related cases.

Fixes: ea707584bac1 ("Staging: IIO: DDS: AD9832 / AD9835 driver")
Cc: stable@vger.kernel.org
Signed-off-by: Zicheng Qu <quzicheng@huawei.com>
Link: https://patch.msgid.link/20241107011015.2472600-3-quzicheng@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
staging: iio: ad9834: Correct phase range check 2025-02-01T17:18:46+00:00 Zicheng Qu quzicheng@huawei.com 2024-11-07T01:10:14+00:00 9d16b310e428ac596bb52d4d890c2c203f6a0234 commit c0599762f0c7e260b99c6b7bceb8eae69b804c94 upstream. User Perspective: When a user sets the phase value, the ad9834_write_phase() is called. The phase register has a 12-bit resolution, so the valid range is 0 to 4095. If the phase offset value of 4096 is input, it effectively exactly equals 0 in the lower 12 bits, meaning no offset. Reasons for the Change: 1) Original Condition (phase > BIT(AD9834_PHASE_BITS)): This condition allows a phase value equal to 2^12, which is 4096. However, this value exceeds the valid 12-bit range, as the maximum valid phase value should be 4095. 2) Modified Condition (phase >= BIT(AD9834_PHASE_BITS)): Ensures that the phase value is within the valid range, preventing invalid datafrom being written. Impact on Subsequent Logic: st->data = cpu_to_be16(addr | phase): If the phase value is 2^12, i.e., 4096 (0001 0000 0000 0000), and addr is AD9834_REG_PHASE0 (1100 0000 0000 0000), then addr | phase results in 1101 0000 0000 0000, occupying DB12. According to the section of WRITING TO A PHASE REGISTER in the datasheet, the MSB 12 PHASE0 bits should be DB11. The original condition leads to incorrect DB12 usage, which contradicts the datasheet and could pose potential issues for future updates if DB12 is used in such related cases. Fixes: 12b9d5bf76bf ("Staging: IIO: DDS: AD9833 / AD9834 driver") Cc: stable@vger.kernel.org Signed-off-by: Zicheng Qu <quzicheng@huawei.com> Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org> Link: https://patch.msgid.link/20241107011015.2472600-2-quzicheng@huawei.com Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c0599762f0c7e260b99c6b7bceb8eae69b804c94 upstream.

User Perspective:
When a user sets the phase value, the ad9834_write_phase() is called.
The phase register has a 12-bit resolution, so the valid range is 0 to
4095. If the phase offset value of 4096 is input, it effectively exactly
equals 0 in the lower 12 bits, meaning no offset.

Reasons for the Change:
1) Original Condition (phase > BIT(AD9834_PHASE_BITS)):
This condition allows a phase value equal to 2^12, which is 4096.
However, this value exceeds the valid 12-bit range, as the maximum valid
phase value should be 4095.
2) Modified Condition (phase >= BIT(AD9834_PHASE_BITS)):
Ensures that the phase value is within the valid range, preventing
invalid datafrom being written.

Impact on Subsequent Logic: st->data = cpu_to_be16(addr | phase):
If the phase value is 2^12, i.e., 4096 (0001 0000 0000 0000), and addr
is AD9834_REG_PHASE0 (1100 0000 0000 0000), then addr | phase results in
1101 0000 0000 0000, occupying DB12. According to the section of WRITING
TO A PHASE REGISTER in the datasheet, the MSB 12 PHASE0 bits should be
DB11. The original condition leads to incorrect DB12 usage, which
contradicts the datasheet and could pose potential issues for future
updates if DB12 is used in such related cases.

Fixes: 12b9d5bf76bf ("Staging: IIO: DDS: AD9833 / AD9834 driver")
Cc: stable@vger.kernel.org
Signed-off-by: Zicheng Qu <quzicheng@huawei.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://patch.msgid.link/20241107011015.2472600-2-quzicheng@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
media: platform: allegro-dvt: Fix possible memory leak in allocate_buffers_internal() 2024-12-14T18:44:43+00:00 Gaosheng Cui cuigaosheng1@huawei.com 2024-10-09T08:28:02+00:00 cf642904be39ae0d441dbdfa8f485e0a46260be4 commit 0f514068fbc5d4d189c817adc7c4e32cffdc2e47 upstream. The buffer in the loop should be released under the exception path, otherwise there may be a memory leak here. To mitigate this, free the buffer when allegro_alloc_buffer fails. Fixes: f20387dfd065 ("media: allegro: add Allegro DVT video IP core driver") Cc: <stable@vger.kernel.org> Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0f514068fbc5d4d189c817adc7c4e32cffdc2e47 upstream.

The buffer in the loop should be released under the exception path,
otherwise there may be a memory leak here.

To mitigate this, free the buffer when allegro_alloc_buffer fails.

Fixes: f20387dfd065 ("media: allegro: add Allegro DVT video IP core driver")
Cc: <stable@vger.kernel.org>
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
comedi: Flush partial mappings in error case 2024-12-14T18:44:36+00:00 Jann Horn jannh@google.com 2024-10-17T19:07:45+00:00 57f048c2d205b85e34282a9b0b0ae177e84c2f44 commit ce8f9fb651fac95dd41f69afe54d935420b945bd upstream. If some remap_pfn_range() calls succeeded before one failed, we still have buffer pages mapped into the userspace page tables when we drop the buffer reference with comedi_buf_map_put(bm). The userspace mappings are only cleaned up later in the mmap error path. Fix it by explicitly flushing all mappings in our VMA on the error path. See commit 79a61cc3fc04 ("mm: avoid leaving partial pfn mappings around in error case"). Cc: stable@vger.kernel.org Fixes: ed9eccbe8970 ("Staging: add comedi core") Signed-off-by: Jann Horn <jannh@google.com> Link: https://lore.kernel.org/r/20241017-comedi-tlb-v3-1-16b82f9372ce@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ce8f9fb651fac95dd41f69afe54d935420b945bd upstream.

If some remap_pfn_range() calls succeeded before one failed, we still have
buffer pages mapped into the userspace page tables when we drop the buffer
reference with comedi_buf_map_put(bm). The userspace mappings are only
cleaned up later in the mmap error path.

Fix it by explicitly flushing all mappings in our VMA on the error path.

See commit 79a61cc3fc04 ("mm: avoid leaving partial pfn mappings around in
error case").

Cc: stable@vger.kernel.org
Fixes: ed9eccbe8970 ("Staging: add comedi core")
Signed-off-by: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/r/20241017-comedi-tlb-v3-1-16b82f9372ce@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
staging: greybus: uart: clean up TIOCGSERIAL 2024-12-14T18:44:34+00:00 Johan Hovold johan@kernel.org 2021-04-07T10:23:25+00:00 d6de1aaa0fb9c9553034a2e7d232d072dc062914 [ Upstream commit d38be702452137fa82a56ff7cc577d829add1637 ] TIOCSSERIAL is a horrid, underspecified, legacy interface which for most serial devices is only useful for setting the close_delay and closing_wait parameters. The xmit_fifo_size parameter could be used to set the hardware transmit fifo size of a legacy UART when it could not be detected, but the interface is limited to eight bits and should be left unset when not used. Similarly, baud_base could be used to set the UART base clock when it could not be detected but might as well be left unset when it is not known. The type parameter could be used to set the UART type, but is better left unspecified (type unknown) when it isn't used. Note that some applications have historically expected TIOCGSERIAL to be implemented, but judging from the Debian sources, the port type not being PORT_UNKNOWN is only used to check for the existence of legacy serial ports (ttySn). Notably USB serial drivers like ftdi_sio have been using PORT_UNKNOWN for twenty years without any problems. Drop the bogus values provided by the greybus implementation. Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210407102334.32361-8-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Stable-dep-of: fe0ebeafc3b7 ("staging: greybus: uart: Fix atomicity violation in get_serial_info()") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit d38be702452137fa82a56ff7cc577d829add1637 ]

TIOCSSERIAL is a horrid, underspecified, legacy interface which for most
serial devices is only useful for setting the close_delay and
closing_wait parameters.

The xmit_fifo_size parameter could be used to set the hardware transmit
fifo size of a legacy UART when it could not be detected, but the
interface is limited to eight bits and should be left unset when not
used.

Similarly, baud_base could be used to set the UART base clock when it
could not be detected but might as well be left unset when it is not
known.

The type parameter could be used to set the UART type, but is
better left unspecified (type unknown) when it isn't used.

Note that some applications have historically expected TIOCGSERIAL to be
implemented, but judging from the Debian sources, the port type not
being PORT_UNKNOWN is only used to check for the existence of legacy
serial ports (ttySn). Notably USB serial drivers like ftdi_sio have been
using PORT_UNKNOWN for twenty years without any problems.

Drop the bogus values provided by the greybus implementation.

Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210407102334.32361-8-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: fe0ebeafc3b7 ("staging: greybus: uart: Fix atomicity violation in get_serial_info()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
staging: iio: frequency: ad9832: fix division by zero in ad9832_calc_freqreg() 2024-11-08T15:20:53+00:00 Zicheng Qu quzicheng@huawei.com 2024-10-22T13:43:54+00:00 fcd6b59f7a774558e2525251c68aa37aff748e55 commit 6bd301819f8f69331a55ae2336c8b111fc933f3d upstream. In the ad9832_write_frequency() function, clk_get_rate() might return 0. This can lead to a division by zero when calling ad9832_calc_freqreg(). The check if (fout > (clk_get_rate(st->mclk) / 2)) does not protect against the case when fout is 0. The ad9832_write_frequency() function is called from ad9832_write(), and fout is derived from a text buffer, which can contain any value. Link: https://lore.kernel.org/all/2024100904-CVE-2024-47663-9bdc@gregkh/ Fixes: ea707584bac1 ("Staging: IIO: DDS: AD9832 / AD9835 driver") Cc: stable@vger.kernel.org Signed-off-by: Zicheng Qu <quzicheng@huawei.com> Reviewed-by: Nuno Sa <nuno.sa@analog.com> Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org> Link: https://patch.msgid.link/20241022134354.574614-1-quzicheng@huawei.com Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 6bd301819f8f69331a55ae2336c8b111fc933f3d upstream.

In the ad9832_write_frequency() function, clk_get_rate() might return 0.
This can lead to a division by zero when calling ad9832_calc_freqreg().
The check if (fout > (clk_get_rate(st->mclk) / 2)) does not protect
against the case when fout is 0. The ad9832_write_frequency() function
is called from ad9832_write(), and fout is derived from a text buffer,
which can contain any value.

Link: https://lore.kernel.org/all/2024100904-CVE-2024-47663-9bdc@gregkh/
Fixes: ea707584bac1 ("Staging: IIO: DDS: AD9832 / AD9835 driver")
Cc: stable@vger.kernel.org
Signed-off-by: Zicheng Qu <quzicheng@huawei.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://patch.msgid.link/20241022134354.574614-1-quzicheng@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
wifi: wilc1000: fix potential RCU dereference issue in wilc_parse_join_bss_param 2024-11-08T15:20:27+00:00 Jiawei Ye jiawei.ye@foxmail.com 2024-08-29T08:17:09+00:00 5a24cedc243ace5ed7c1016f52a7bfc8f5b07815 [ Upstream commit 6d7c6ae1efb1ff68bc01d79d94fdf0388f86cdd8 ] In the `wilc_parse_join_bss_param` function, the TSF field of the `ies` structure is accessed after the RCU read-side critical section is unlocked. According to RCU usage rules, this is illegal. Reusing this pointer can lead to unpredictable behavior, including accessing memory that has been updated or causing use-after-free issues. This possible bug was identified using a static analysis tool developed by myself, specifically designed to detect RCU-related issues. To address this, the TSF value is now stored in a local variable `ies_tsf` before the RCU lock is released. The `param->tsf_lo` field is then assigned using this local variable, ensuring that the TSF value is safely accessed. Fixes: 205c50306acf ("wifi: wilc1000: fix RCU usage in connect path") Signed-off-by: Jiawei Ye <jiawei.ye@foxmail.com> Reviewed-by: Alexis Lothoré <alexis.lothore@bootlin.com> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://patch.msgid.link/tencent_466225AA599BA49627FB26F707EE17BC5407@qq.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 6d7c6ae1efb1ff68bc01d79d94fdf0388f86cdd8 ]

In the `wilc_parse_join_bss_param` function, the TSF field of the `ies`
structure is accessed after the RCU read-side critical section is
unlocked. According to RCU usage rules, this is illegal. Reusing this
pointer can lead to unpredictable behavior, including accessing memory
that has been updated or causing use-after-free issues.

This possible bug was identified using a static analysis tool developed
by myself, specifically designed to detect RCU-related issues.

To address this, the TSF value is now stored in a local variable
`ies_tsf` before the RCU lock is released. The `param->tsf_lo` field is
then assigned using this local variable, ensuring that the TSF value is
safely accessed.

Fixes: 205c50306acf ("wifi: wilc1000: fix RCU usage in connect path")
Signed-off-by: Jiawei Ye <jiawei.ye@foxmail.com>
Reviewed-by: Alexis Lothoré <alexis.lothore@bootlin.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://patch.msgid.link/tencent_466225AA599BA49627FB26F707EE17BC5407@qq.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
staging: iio: frequency: ad9834: Validate frequency parameter value 2024-09-12T09:03:55+00:00 Aleksandr Mishin amishin@t-argos.ru 2024-07-03T15:45:06+00:00 0e727707a239d5c519fc9abc2f0fd913516a7e47 commit b48aa991758999d4e8f9296c5bbe388f293ef465 upstream. In ad9834_write_frequency() clk_get_rate() can return 0. In such case ad9834_calc_freqreg() call will lead to division by zero. Checking 'if (fout > (clk_freq / 2))' doesn't protect in case of 'fout' is 0. ad9834_write_frequency() is called from ad9834_write(), where fout is taken from text buffer, which can contain any value. Modify parameters checking. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 12b9d5bf76bf ("Staging: IIO: DDS: AD9833 / AD9834 driver") Suggested-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Aleksandr Mishin <amishin@t-argos.ru> Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org> Link: https://patch.msgid.link/20240703154506.25584-1-amishin@t-argos.ru Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b48aa991758999d4e8f9296c5bbe388f293ef465 upstream.

In ad9834_write_frequency() clk_get_rate() can return 0. In such case
ad9834_calc_freqreg() call will lead to division by zero. Checking
'if (fout > (clk_freq / 2))' doesn't protect in case of 'fout' is 0.
ad9834_write_frequency() is called from ad9834_write(), where fout is
taken from text buffer, which can contain any value.

Modify parameters checking.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 12b9d5bf76bf ("Staging: IIO: DDS: AD9833 / AD9834 driver")
Suggested-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Aleksandr Mishin <amishin@t-argos.ru>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://patch.msgid.link/20240703154506.25584-1-amishin@t-argos.ru
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>