<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/tty, branch v5.17.9</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>serial: 8250_mtk: Fix register address for XON/XOFF character</title>
<updated>2022-05-18T08:28:20+00:00</updated>
<author>
<name>AngeloGioacchino Del Regno</name>
<email>angelogioacchino.delregno@collabora.com</email>
</author>
<published>2022-04-27T13:23:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a75811da73f3a661eef450941cbcbe9c5d90c439'/>
<id>a75811da73f3a661eef450941cbcbe9c5d90c439</id>
<content type='text'>
commit e1bfdbc7daca171c74a577b3dd0b36d76bb0ffcc upstream.

The XON1/XOFF1 character registers are at offset 0xa0 and 0xa8
respectively, so we cannot use the definition in serial_port.h.

Fixes: bdbd0a7f8f03 ("serial: 8250-mtk: modify baudrate setting")
Signed-off-by: AngeloGioacchino Del Regno &lt;angelogioacchino.delregno@collabora.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20220427132328.228297-4-angelogioacchino.delregno@collabora.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e1bfdbc7daca171c74a577b3dd0b36d76bb0ffcc upstream.

The XON1/XOFF1 character registers are at offset 0xa0 and 0xa8
respectively, so we cannot use the definition in serial_port.h.

Fixes: bdbd0a7f8f03 ("serial: 8250-mtk: modify baudrate setting")
Signed-off-by: AngeloGioacchino Del Regno &lt;angelogioacchino.delregno@collabora.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20220427132328.228297-4-angelogioacchino.delregno@collabora.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: 8250_mtk: Fix UART_EFR register address</title>
<updated>2022-05-18T08:28:20+00:00</updated>
<author>
<name>AngeloGioacchino Del Regno</name>
<email>angelogioacchino.delregno@collabora.com</email>
</author>
<published>2022-04-27T13:23:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=36723b9a2bcd9b60e1ebd34783bbc5e10554e91e'/>
<id>36723b9a2bcd9b60e1ebd34783bbc5e10554e91e</id>
<content type='text'>
commit bb0b197aadd928f52ce6f01f0ee977f0a08cf1be upstream.

On MediaTek SoCs, the UART IP is 16550A compatible, but there are some
specific quirks: we are declaring a register shift of 2, but this is
only valid for the majority of the registers, as there are some that
are out of the standard layout.

Specifically, this driver is using definitions from serial_reg.h, where
we have a UART_EFR register defined as 2: this results in a 0x8 offset,
but there we have the FCR register instead.

The right offset for the EFR register on MediaTek UART is at 0x98,
so, following the decimal definition convention in serial_reg.h and
accounting for the register left shift of two, add and use the correct
register address for this IP, defined as decimal 38, so that the final
calculation results in (0x26 &lt;&lt; 2) = 0x98.

Fixes: bdbd0a7f8f03 ("serial: 8250-mtk: modify baudrate setting")
Signed-off-by: AngeloGioacchino Del Regno &lt;angelogioacchino.delregno@collabora.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20220427132328.228297-2-angelogioacchino.delregno@collabora.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit bb0b197aadd928f52ce6f01f0ee977f0a08cf1be upstream.

On MediaTek SoCs, the UART IP is 16550A compatible, but there are some
specific quirks: we are declaring a register shift of 2, but this is
only valid for the majority of the registers, as there are some that
are out of the standard layout.

Specifically, this driver is using definitions from serial_reg.h, where
we have a UART_EFR register defined as 2: this results in a 0x8 offset,
but there we have the FCR register instead.

The right offset for the EFR register on MediaTek UART is at 0x98,
so, following the decimal definition convention in serial_reg.h and
accounting for the register left shift of two, add and use the correct
register address for this IP, defined as decimal 38, so that the final
calculation results in (0x26 &lt;&lt; 2) = 0x98.

Fixes: bdbd0a7f8f03 ("serial: 8250-mtk: modify baudrate setting")
Signed-off-by: AngeloGioacchino Del Regno &lt;angelogioacchino.delregno@collabora.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20220427132328.228297-2-angelogioacchino.delregno@collabora.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fsl_lpuart: Don't enable interrupts too early</title>
<updated>2022-05-18T08:28:20+00:00</updated>
<author>
<name>Indan Zupancic</name>
<email>Indan.Zupancic@mep-info.com</email>
</author>
<published>2022-05-05T11:47:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f8a0a51f90fb09518d9cb662fdddcf58066bd30c'/>
<id>f8a0a51f90fb09518d9cb662fdddcf58066bd30c</id>
<content type='text'>
commit 401fb66a355eb0f22096cf26864324f8e63c7d78 upstream.

If an irq is pending when devm_request_irq() is called, the irq
handler will cause a NULL pointer access because initialisation
is not done yet.

Fixes: 9d7ee0e28da59 ("tty: serial: lpuart: avoid report NULL interrupt")
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Indan Zupancic &lt;Indan.Zupancic@mep-info.com&gt;
Link: https://lore.kernel.org/r/20220505114750.45423-1-Indan.Zupancic@mep-info.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 401fb66a355eb0f22096cf26864324f8e63c7d78 upstream.

If an irq is pending when devm_request_irq() is called, the irq
handler will cause a NULL pointer access because initialisation
is not done yet.

Fixes: 9d7ee0e28da59 ("tty: serial: lpuart: avoid report NULL interrupt")
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Indan Zupancic &lt;Indan.Zupancic@mep-info.com&gt;
Link: https://lore.kernel.org/r/20220505114750.45423-1-Indan.Zupancic@mep-info.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: n_gsm: fix invalid gsmtty_write_room() result</title>
<updated>2022-05-18T08:28:19+00:00</updated>
<author>
<name>Daniel Starke</name>
<email>daniel.starke@siemens.com</email>
</author>
<published>2022-05-04T08:17:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fbbe7fbd4d52897dcad41b1a48aa04e552487134'/>
<id>fbbe7fbd4d52897dcad41b1a48aa04e552487134</id>
<content type='text'>
commit 9361ebfbb79fd1bc8594a487c01ad52cdaa391ea upstream.

gsmtty_write() does not prevent the user to use the full fifo size of 4096
bytes as allocated in gsm_dlci_alloc(). However, gsmtty_write_room() tries
to limit the return value by 'TX_SIZE' and returns a negative value if the
fifo has more than 'TX_SIZE' bytes stored. This is obviously wrong as
'TX_SIZE' is defined as 512.
Define 'TX_SIZE' to the fifo size and use it accordingly for allocation to
keep the current behavior. Return the correct remaining size of the fifo in
gsmtty_write_room() via kfifo_avail().

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke &lt;daniel.starke@siemens.com&gt;
Link: https://lore.kernel.org/r/20220504081733.3494-3-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 9361ebfbb79fd1bc8594a487c01ad52cdaa391ea upstream.

gsmtty_write() does not prevent the user to use the full fifo size of 4096
bytes as allocated in gsm_dlci_alloc(). However, gsmtty_write_room() tries
to limit the return value by 'TX_SIZE' and returns a negative value if the
fifo has more than 'TX_SIZE' bytes stored. This is obviously wrong as
'TX_SIZE' is defined as 512.
Define 'TX_SIZE' to the fifo size and use it accordingly for allocation to
keep the current behavior. Return the correct remaining size of the fifo in
gsmtty_write_room() via kfifo_avail().

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke &lt;daniel.starke@siemens.com&gt;
Link: https://lore.kernel.org/r/20220504081733.3494-3-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: n_gsm: fix mux activation issues in gsm_config()</title>
<updated>2022-05-18T08:28:19+00:00</updated>
<author>
<name>Daniel Starke</name>
<email>daniel.starke@siemens.com</email>
</author>
<published>2022-05-04T08:17:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6e31ead009b2c7d4fb856b3416f43748fb9b5d12'/>
<id>6e31ead009b2c7d4fb856b3416f43748fb9b5d12</id>
<content type='text'>
commit edd5f60c340086891fab094ad61270d6c80f9ca4 upstream.

The current implementation activates the mux if it was restarted and opens
the control channel if the mux was previously closed and we are now acting
as initiator instead of responder, which is the default setting.
This has two issues.
1) No mux is activated if we keep all default values and only switch to
initiator. The control channel is not allocated but will be opened next
which results in a NULL pointer dereference.
2) Switching the configuration after it was once configured while keeping
the initiator value the same will not reopen the control channel if it was
closed due to parameter incompatibilities. The mux remains dead.

Fix 1) by always activating the mux if it is dead after configuration.
Fix 2) by always opening the control channel after mux activation.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke &lt;daniel.starke@siemens.com&gt;
Link: https://lore.kernel.org/r/20220504081733.3494-2-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit edd5f60c340086891fab094ad61270d6c80f9ca4 upstream.

The current implementation activates the mux if it was restarted and opens
the control channel if the mux was previously closed and we are now acting
as initiator instead of responder, which is the default setting.
This has two issues.
1) No mux is activated if we keep all default values and only switch to
initiator. The control channel is not allocated but will be opened next
which results in a NULL pointer dereference.
2) Switching the configuration after it was once configured while keeping
the initiator value the same will not reopen the control channel if it was
closed due to parameter incompatibilities. The mux remains dead.

Fix 1) by always activating the mux if it is dead after configuration.
Fix 2) by always opening the control channel after mux activation.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke &lt;daniel.starke@siemens.com&gt;
Link: https://lore.kernel.org/r/20220504081733.3494-2-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: n_gsm: fix buffer over-read in gsm_dlci_data()</title>
<updated>2022-05-18T08:28:19+00:00</updated>
<author>
<name>Daniel Starke</name>
<email>daniel.starke@siemens.com</email>
</author>
<published>2022-05-04T08:17:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8b1ce42be3a6cde06e07555304ca56b5afcf65b0'/>
<id>8b1ce42be3a6cde06e07555304ca56b5afcf65b0</id>
<content type='text'>
commit fd442e5ba30aaa75ea47b32149e7a3110dc20a46 upstream.

'len' is decreased after each octet that has its EA bit set to 0, which
means that the value is encoded with additional octets. However, the final
octet does not decreases 'len' which results in 'len' being one byte too
long. A buffer over-read may occur in tty_insert_flip_string() as it tries
to read one byte more than the passed content size of 'data'.
Decrease 'len' also for the final octet which has the EA bit set to 1 to
write the correct number of bytes from the internal receive buffer to the
virtual tty.

Fixes: 2e124b4a390c ("TTY: switch tty_flip_buffer_push")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke &lt;daniel.starke@siemens.com&gt;
Link: https://lore.kernel.org/r/20220504081733.3494-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit fd442e5ba30aaa75ea47b32149e7a3110dc20a46 upstream.

'len' is decreased after each octet that has its EA bit set to 0, which
means that the value is encoded with additional octets. However, the final
octet does not decreases 'len' which results in 'len' being one byte too
long. A buffer over-read may occur in tty_insert_flip_string() as it tries
to read one byte more than the passed content size of 'data'.
Decrease 'len' also for the final octet which has the EA bit set to 1 to
write the correct number of bytes from the internal receive buffer to the
virtual tty.

Fixes: 2e124b4a390c ("TTY: switch tty_flip_buffer_push")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke &lt;daniel.starke@siemens.com&gt;
Link: https://lore.kernel.org/r/20220504081733.3494-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty/serial: digicolor: fix possible null-ptr-deref in digicolor_uart_probe()</title>
<updated>2022-05-18T08:28:19+00:00</updated>
<author>
<name>Yang Yingliang</name>
<email>yangyingliang@huawei.com</email>
</author>
<published>2022-05-05T12:46:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4bb92ab559d75a0d04256c9b9e1032582a40a183'/>
<id>4bb92ab559d75a0d04256c9b9e1032582a40a183</id>
<content type='text'>
commit 447ee1516f19f534a228dda237eddb202f23e163 upstream.

It will cause null-ptr-deref when using 'res', if platform_get_resource()
returns NULL, so move using 'res' after devm_ioremap_resource() that
will check it to avoid null-ptr-deref.
And use devm_platform_get_and_ioremap_resource() to simplify code.

Fixes: 5930cb3511df ("serial: driver for Conexant Digicolor USART")
Signed-off-by: Yang Yingliang &lt;yangyingliang@huawei.com&gt;
Reviewed-by: Baruch Siach &lt;baruch@tkos.co.il&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20220505124621.1592697-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 447ee1516f19f534a228dda237eddb202f23e163 upstream.

It will cause null-ptr-deref when using 'res', if platform_get_resource()
returns NULL, so move using 'res' after devm_ioremap_resource() that
will check it to avoid null-ptr-deref.
And use devm_platform_get_and_ioremap_resource() to simplify code.

Fixes: 5930cb3511df ("serial: driver for Conexant Digicolor USART")
Signed-off-by: Yang Yingliang &lt;yangyingliang@huawei.com&gt;
Reviewed-by: Baruch Siach &lt;baruch@tkos.co.il&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20220505124621.1592697-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: n_gsm: fix sometimes uninitialized warning in gsm_dlci_modem_output()</title>
<updated>2022-05-09T07:16:33+00:00</updated>
<author>
<name>Daniel Starke</name>
<email>daniel.starke@siemens.com</email>
</author>
<published>2022-04-25T10:47:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e578ba015ce8a495ecbb03597c8b30c40841b6bb'/>
<id>e578ba015ce8a495ecbb03597c8b30c40841b6bb</id>
<content type='text'>
commit 19317433057dc1f2ca9a975e4e6b547282c2a5ef upstream.

'size' may be used uninitialized in gsm_dlci_modem_output() if called with
an adaption that is neither 1 nor 2. The function is currently only called
by gsm_modem_upd_via_data() and only for adaption 2.
Properly handle every invalid case by returning -EINVAL to silence the
compiler warning and avoid future regressions.

Fixes: c19ffe00fed6 ("tty: n_gsm: fix invalid use of MSC in advanced option")
Cc: stable@vger.kernel.org
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Daniel Starke &lt;daniel.starke@siemens.com&gt;
Link: https://lore.kernel.org/r/20220425104726.7986-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 19317433057dc1f2ca9a975e4e6b547282c2a5ef upstream.

'size' may be used uninitialized in gsm_dlci_modem_output() if called with
an adaption that is neither 1 nor 2. The function is currently only called
by gsm_modem_upd_via_data() and only for adaption 2.
Properly handle every invalid case by returning -EINVAL to silence the
compiler warning and avoid future regressions.

Fixes: c19ffe00fed6 ("tty: n_gsm: fix invalid use of MSC in advanced option")
Cc: stable@vger.kernel.org
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Daniel Starke &lt;daniel.starke@siemens.com&gt;
Link: https://lore.kernel.org/r/20220425104726.7986-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: n_gsm: fix software flow control handling</title>
<updated>2022-05-09T07:16:33+00:00</updated>
<author>
<name>Daniel Starke</name>
<email>daniel.starke@siemens.com</email>
</author>
<published>2022-04-22T07:10:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a5e357c8e7c252ba7421d6c0323012d08251603a'/>
<id>a5e357c8e7c252ba7421d6c0323012d08251603a</id>
<content type='text'>
commit f4f7d63287217ba25e5c80f5faae5e4f7118790e upstream.

n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.4.8.1 states that XON/XOFF characters
shall be used instead of Fcon/Fcoff command in advanced option mode to
handle flow control. Chapter 5.4.8.2 describes how XON/XOFF characters
shall be handled. Basic option mode only used Fcon/Fcoff commands and no
XON/XOFF characters. These are treated as data bytes here.
The current implementation uses the gsm_mux field 'constipated' to handle
flow control from the remote peer and the gsm_dlci field 'constipated' to
handle flow control from each DLCI. The later is unrelated to this patch.
The gsm_mux field is correctly set for Fcon/Fcoff commands in
gsm_control_message(). However, the same is not true for XON/XOFF
characters in gsm1_receive().
Disable software flow control handling in the tty to allow explicit
handling by n_gsm.
Add the missing handling in advanced option mode for gsm_mux in
gsm1_receive() to comply with the standard.

This patch depends on the following commit:
Commit 8838b2af23ca ("tty: n_gsm: fix SW flow control encoding/handling")

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke &lt;daniel.starke@siemens.com&gt;
Link: https://lore.kernel.org/r/20220422071025.5490-3-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f4f7d63287217ba25e5c80f5faae5e4f7118790e upstream.

n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.4.8.1 states that XON/XOFF characters
shall be used instead of Fcon/Fcoff command in advanced option mode to
handle flow control. Chapter 5.4.8.2 describes how XON/XOFF characters
shall be handled. Basic option mode only used Fcon/Fcoff commands and no
XON/XOFF characters. These are treated as data bytes here.
The current implementation uses the gsm_mux field 'constipated' to handle
flow control from the remote peer and the gsm_dlci field 'constipated' to
handle flow control from each DLCI. The later is unrelated to this patch.
The gsm_mux field is correctly set for Fcon/Fcoff commands in
gsm_control_message(). However, the same is not true for XON/XOFF
characters in gsm1_receive().
Disable software flow control handling in the tty to allow explicit
handling by n_gsm.
Add the missing handling in advanced option mode for gsm_mux in
gsm1_receive() to comply with the standard.

This patch depends on the following commit:
Commit 8838b2af23ca ("tty: n_gsm: fix SW flow control encoding/handling")

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke &lt;daniel.starke@siemens.com&gt;
Link: https://lore.kernel.org/r/20220422071025.5490-3-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: n_gsm: fix invalid use of MSC in advanced option</title>
<updated>2022-05-09T07:16:33+00:00</updated>
<author>
<name>Daniel Starke</name>
<email>daniel.starke@siemens.com</email>
</author>
<published>2022-04-22T07:10:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4ee8705e30a4a85afb9c8a2449ab4e51be2bf8cc'/>
<id>4ee8705e30a4a85afb9c8a2449ab4e51be2bf8cc</id>
<content type='text'>
commit c19ffe00fed6bb423d81406d2a7e5793074c7d83 upstream.

n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.4.6.3.7 states that the Modem Status
Command (MSC) shall only be used if the basic option was chosen.
The current implementation uses MSC frames even if advanced option was
chosen to inform the peer about modem line state updates. A standard
conform peer may choose to discard these frames in advanced option mode.
Furthermore, gsmtty_modem_update() is not part of the 'tty_operations'
functions despite its name.
Rename gsmtty_modem_update() to gsm_modem_update() to clarify this. Split
its function into gsm_modem_upd_via_data() and gsm_modem_upd_via_msc()
depending on the encoding and adaption. Introduce gsm_dlci_modem_output()
as adaption of gsm_dlci_data_output() to encode and queue empty frames in
advanced option mode. Use it in gsm_modem_upd_via_data().
gsm_modem_upd_via_msc() is based on the initial gsmtty_modem_update()
function which used only MSC frames to update modem states.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke &lt;daniel.starke@siemens.com&gt;
Link: https://lore.kernel.org/r/20220422071025.5490-2-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit c19ffe00fed6bb423d81406d2a7e5793074c7d83 upstream.

n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.4.6.3.7 states that the Modem Status
Command (MSC) shall only be used if the basic option was chosen.
The current implementation uses MSC frames even if advanced option was
chosen to inform the peer about modem line state updates. A standard
conform peer may choose to discard these frames in advanced option mode.
Furthermore, gsmtty_modem_update() is not part of the 'tty_operations'
functions despite its name.
Rename gsmtty_modem_update() to gsm_modem_update() to clarify this. Split
its function into gsm_modem_upd_via_data() and gsm_modem_upd_via_msc()
depending on the encoding and adaption. Introduce gsm_dlci_modem_output()
as adaption of gsm_dlci_data_output() to encode and queue empty frames in
advanced option mode. Use it in gsm_modem_upd_via_data().
gsm_modem_upd_via_msc() is based on the initial gsmtty_modem_update()
function which used only MSC frames to update modem states.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke &lt;daniel.starke@siemens.com&gt;
Link: https://lore.kernel.org/r/20220422071025.5490-2-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
