Add constants for the prescaler and divisor registers. Document and
name register 0x25, and put the LCR define to more use.
The 0x25 register (CH341_REG_LCR2) is only used by CH341 chips before
version 0x30 and is involved in configuring the line control parameters.
It's not known to the author whether there any such chips in the wild,
and Linux' ch341 driver never supported them. For chip version 0x30 and
above the 0x25 register is always set to zero. The alternative would've
been to not set the register at all, but that may have unintended
effects.
Signed-off-by: Michael Hanselmann <public@hansmi.ch>
Link: https://lore.kernel.org/r/2e80916d-1be8-dc0f-abf9-adc0feea1803@msgid.hansmi.ch
[ johan: fix up comment ]
Signed-off-by: Johan Hovold <johan@kernel.org>
Add PID for CH340 that's found on some ESP8266 dev boards made by
LilyGO. The specific device that contains such serial converter can be
seen here: https://github.com/LilyGO/LILYGO-T-OI.
Apparently, it's a regular CH340, but I've confirmed with others that
also bought this board that the PID found on this device (0x7522)
differs from other devices with the "same" converter (0x7523).
Simply adding its PID to the driver and rebuilding it made it work
as expected.
Signed-off-by: Igor Moura <imphilippini@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
This is a UPB (Universal Powerline Bus) PIM (Powerline Interface Module)
which allows for controlling multiple UPB compatible devices from Linux
using the standard serial interface.
Based on vendor application source code there are two different models
of USB based PIM devices in addition to a number of RS232 based PIM's.
The vendor UPB application source contains the following USB ID's:
#define USB_PCS_VENDOR_ID 0x04b4
#define USB_PCS_PIM_PRODUCT_ID 0x5500
#define USB_SAI_VENDOR_ID 0x17dd
#define USB_SAI_PIM_PRODUCT_ID 0x5500
The first set of ID's correspond to the PIM variant sold by Powerline
Control Systems while the second corresponds to the Simply Automated
Incorporated PIM. As the product ID for both of these match the default
cypress HID->COM RS232 product ID it assumed that they both use an
internal variant of this HID->COM RS232 converter hardware. However
as the vendor ID for the Simply Automated variant is different we need
to also add it to the cypress_M8 driver so that it is properly
detected.
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Link: https://lore.kernel.org/r/20200616220403.1807003-1-james.hilliard1@gmail.com
Cc: stable@vger.kernel.org
[ johan: amend VID define entry ]
Signed-off-by: Johan Hovold <johan@kernel.org>
The sierra driver had two different functions for trying to determine
different quirks that did the same exact thing. Remove one and rename
things to make it more obvious exactly what the different lists do.
Cc: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20200618094300.1887727-6-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.
This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.
There are a variety of indentation styles found.
a) 4 spaces + '---help---'
b) 7 spaces + '---help---'
c) 8 spaces + '---help---'
d) 1 space + 1 tab + '---help---'
e) 1 tab + '---help---' (correct indentation)
f) 1 tab + 1 space + '---help---'
g) 1 tab + 2 spaces + '---help---'
In order to convert all of them to 1 tab + 'help', I ran the
following commend:
$ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Here are some new modem device ids.
All have been in linux-next with no reported issues.
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Merge tag 'usb-serial-5.8-rc1-2' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next
Johan writes:
USB-serial fixes for 5.8-rc1
Here are some new modem device ids.
All have been in linux-next with no reported issues.
* tag 'usb-serial-5.8-rc1-2' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
USB: serial: option: add Telit LE910C1-EUX compositions
USB: serial: qcserial: add DW5816e QDL support
Here are the USB-serial updates for 5.8-rc1, including:
- a SPDX comment-style clean up
- a fix usb_wwan modem drivers which could end up resubmitting the
their read URBs in a tight loop on disconnect
- a regression fix for a subset of quirky ch341 devices which would
lock up on certain low line speeds when using the new divisor
algorithm
All have been in linux-next with no reported issues.
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Merge tag 'usb-serial-5.8-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next
Johan writes:
USB-serial updates for 5.8-rc1
Here are the USB-serial updates for 5.8-rc1, including:
- a SPDX comment-style clean up
- a fix usb_wwan modem drivers which could end up resubmitting the
their read URBs in a tight loop on disconnect
- a regression fix for a subset of quirky ch341 devices which would
lock up on certain low line speeds when using the new divisor
algorithm
All have been in linux-next with no reported issues.
* tag 'usb-serial-5.8-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
USB: serial: ch341: fix lockup of devices with limited prescaler
USB: serial: ch341: add basis for quirk detection
USB: serial: usb_wwan: do not resubmit rx urb on fatal errors
USB: serial: Use the correct style for SPDX License Identifier
Michael Hanselmann reports that
[a] subset of all CH341 devices stop responding to bulk
transfers, usually after the third byte, when the highest
prescaler bit (0b100) is set. There is one exception, namely a
prescaler of exactly 0b111 (fact=1, ps=3).
Fix this by forcing a lower base clock (fact = 0) whenever needed.
This specifically makes the standard rates 110, 134 and 200 bps work
again with these devices.
Fixes: 3571456508 ("USB: serial: ch341: reimplement line-speed handling")
Cc: stable <stable@vger.kernel.org> # 5.5
Reported-by: Michael Hanselmann <public@hansmi.ch>
Link: https://lore.kernel.org/r/20200514141743.GE25962@localhost
Signed-off-by: Johan Hovold <johan@kernel.org>
A subset of CH341 devices does not support all features, namely the
prescaler is limited to a reduced precision and there is no support for
sending a RS232 break condition. This patch adds a detection function
which will be extended to set quirk flags as they're implemented.
The author's affected device has an imprint of "340" on the
turquoise-colored plug, but not all such devices appear to be affected.
Signed-off-by: Michael Hanselmann <public@hansmi.ch>
Link: https://lore.kernel.org/r/1e1ae0da6082bb528a44ef323d4e1d3733d38858.1585697281.git.public@hansmi.ch
[ johan: use long type for quirks; rephrase and use port device for
messages; handle short reads; set quirk flags directly in
helper function ]
Cc: stable <stable@vger.kernel.org> # 5.5
Signed-off-by: Johan Hovold <johan@kernel.org>
Add support for Dell Wireless 5816e Download Mode (AKA boot & hold mode /
QDL download mode) to drivers/usb/serial/qcserial.c
This is required to update device firmware.
Signed-off-by: Matt Jolly <Kangie@footclan.ninja>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
usb_wwan_indat_callback() shouldn't resubmit rx urb if the previous urb
status is a fatal error. Or the usb controller would keep processing the
new urbs then run into interrupt storm, and has no chance to recover.
Fixes: 6c1ee66a0b ("USB-Serial: Fix error handling of usb_wwan")
Cc: stable@vger.kernel.org
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Add support for Dell Wireless 5816e to drivers/usb/serial/qcserial.c
Signed-off-by: Matt Jolly <Kangie@footclan.ninja>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
This patch corrects the SPDX License Identifier style in
header files related to USB Serial device configuration.
For C header files Documentation/process/license-rules.rst
mandates C-like comments (opposed to C source files where
C++ style should be used).
Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46.
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
We must not process packets shorter than a packet ID
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Reported-and-tested-by: syzbot+d29e9263e13ce0b9f4fd@syzkaller.appspotmail.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Here are the USB-serial updates for 5.7-rc1, including:
- support for a new family of Fintek devices
- fix for an io-edgeport slab-out-of-bounds access
- fixes for a couple of kernel-doc issues
Included are also various clean ups and some new modem device ids.
All but the io-edgeport fix have been in linux-next with no reported
issues.
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Merge tag 'usb-serial-5.7-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next
Johan writes:
USB-serial updates for 5.7-rc1
Here are the USB-serial updates for 5.7-rc1, including:
- support for a new family of Fintek devices
- fix for an io-edgeport slab-out-of-bounds access
- fixes for a couple of kernel-doc issues
Included are also various clean ups and some new modem device ids.
All but the io-edgeport fix have been in linux-next with no reported
issues.
* tag 'usb-serial-5.7-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
USB: serial: io_edgeport: fix slab-out-of-bounds read in edge_interrupt_callback
USB: serial: option: add Wistron Neweb D19Q1
USB: serial: option: add BroadMobi BM806U
USB: serial: option: add support for ASKEY WWHC050
USB: serial: f81232: add control driver for F81534A
USB: serial: fix tty cleanup-op kernel-doc
USB: serial: clean up carrier-detect helper
USB: serial: f81232: set F81534A serial port with RS232 mode
USB: serial: f81232: add F81534A support
USB: serial: f81232: use devm_kzalloc for port data
USB: serial: f81232: add tx_empty function
USB: serial: f81232: extract LSR handler
USB: serial: digi_acceleport: remove redundant assignment to pointer priv
USB: serial: relax unthrottle memory barrier
Fix slab-out-of-bounds read in the interrupt-URB completion handler.
The boundary condition should be (length - 1) as we access
data[position + 1].
Reported-and-tested-by: syzbot+37ba33391ad5f3935bbd@syzkaller.appspotmail.com
Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
The Fintek F81534A series contains 1 HUB, 1 GPIO device and n UARTs. The
UARTs are disabled by default and need to be enabled by the GPIO device
(2c42:16F8).
When F81534A plug to host, we can only see 1 HUB and 1 GPIO device and
we write 0x8fff to GPIO device register F81534A_CTRL_CMD_ENABLE_PORT
(116h) to enable all available serial ports.
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
[johan: reword commit message and an error message slightly]
Signed-off-by: Johan Hovold <johan@kernel.org>
Add a device id for HP LD381 Display
LD381: 03f0:0f7f
Signed-off-by: Scott Chen <scott@labau.com.tw>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Drop the struct tty_port pointer and rename the struct usb_serial_port
pointer "port", which is the named used throughout the subsystem and
incidentally also matches the kernel-doc comment.
Signed-off-by: Johan Hovold <johan@kernel.org>
The Fintek F81532A/534A/535/536 is USB-to-2/4/8/12 serial ports device
and the serial ports are default disabled. Each port contains max 3 pins
GPIO and the 3 pins are default pull high with input mode.
When the serial port had activated (running probe()), we'll transform the
3 pins from GPIO function publicly to control Tranceiver privately use.
We'll default set to 0/0/1 for control transceiver to RS232 mode.
Otherwise, If the serial port is not active, the 3 pins is in GPIO mode
and controlled by global GPIO device with VID/PID: 2c42/16f8.
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
The Fintek F81532A/534A/535/536 is USB-to-2/4/8/12 serial ports device
and the serial port is default disabled when plugin computer.
The IC is contains devices as following:
1. HUB (all devices is connected with this hub)
2. GPIO/Control device. (enable serial port and control GPIOs)
3. serial port 1 to x (2/4/8/12)
It's most same with F81232, the UART device is difference as follow:
1. TX/RX bulk size is 128/512bytes
2. RX bulk layout change:
F81232: [LSR(1Byte)+DATA(1Byte)][LSR(1Byte)+DATA(1Byte)]...
F81534A:[LEN][Data.....][LSR]
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
[johan: reword an error message]
Signed-off-by: Johan Hovold <johan@kernel.org>
Use devm_kzalloc() to replace kzalloc() in port_probe().
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Add tx_empty() function for F81232. Without this, console redirection will
get garbage data.
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Extract LSR handler to function that can be re-used by
F81532A/534A/535/536.
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: https://lore.kernel.org/r/20200220132017.GA29262@embeddedor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pointer priv is being assigned with a value that is never read, it is
assigned a new value later on in a for-loop. The assignment is
redundant and can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Commit a8d78d9f38 ("USB: serial: clean up throttle handling")
converted the throttle handling to use atomic bitops. This means that we
can relax the smp_mb() in unthrottle() to smp_mb__after_atomic(), which
for example is a no-op on architectures like x86 that provide fully
ordered atomics.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Johan Hovold <johan@kernel.org>
While assumed not to make a difference, not using the factor-2 prescaler
makes the receiver more susceptible to errors.
Specifically, there have been reports of problems with devices that
cannot generate a 115200 rate with a smaller error than 2.1% (e.g.
117647 bps). But this can also be reproduced with a low-speed RS232
tranceiver at 115200 when the input rate matches the nominal rate.
So whenever possible, enable the factor-2 prescaler and halve the
divisor in order to use settings closer to that of the previous
algorithm.
Fixes: 3571456508 ("USB: serial: ch341: reimplement line-speed handling")
Cc: stable <stable@vger.kernel.org> # 5.5
Reported-by: Jakub Nantl <jn@forever.cz>
Tested-by: Jakub Nantl <jn@forever.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
The "actual_length" variable might be uninitialized on some failure
paths. It's harmless but static analysis tools like Smatch complain
and at runtime the UBSan tool will likely complain as well.
Fixes: e7542bc382 ("USB: serial: ir-usb: make set_termios synchronous")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
- a missing ir-usb endpoint sanity check
- fixes for two long-standing regressions in ir-usb
- opticon chars_in_buffer support
Included are also various clean ups.
All have been in linux-next with no reported issues.
Signed-off-by: Johan Hovold <johan@kernel.org>
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Merge tag 'usb-serial-5.6-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next
Johan writes:
Here are the USB-serial updates for 5.6-rc1, including:
- a missing ir-usb endpoint sanity check
- fixes for two long-standing regressions in ir-usb
- opticon chars_in_buffer support
Included are also various clean ups.
All have been in linux-next with no reported issues.
Signed-off-by: Johan Hovold <johan@kernel.org>
* tag 'usb-serial-5.6-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
USB: serial: cyberjack: fix spelling mistake "To" -> "Too"
USB: serial: ir-usb: simplify endpoint check
USB: serial: ir-usb: make set_termios synchronous
USB: serial: ir-usb: fix IrLAP framing
USB: serial: ir-usb: fix link-speed handling
USB: serial: ir-usb: add missing endpoint sanity check
USB: serial: garmin_gps: Use flexible-array member
USB: serial: opticon: stop all I/O on close()
USB: serial: opticon: add chars_in_buffer() implementation
There is a spelling mistake in a dev_dbg message. Fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Simplify the endpoint sanity check by letting core verify that the
required endpoints are present.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Use a synchronous usb_bulk_msg() when switching link speed in
set_termios(). This way we do not need to keep track of outstanding URBs
in order to be able to stop them at close.
Note that there's no need to set URB_ZERO_PACKET as the one-byte
transfer will always be short.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Commit f4a4cbb204 ("USB: ir-usb: reimplement using generic framework")
switched to using the generic write implementation which may combine
multiple write requests into larger transfers. This can break the IrLAP
protocol where end-of-frame is determined using the USB short packet
mechanism, for example, if multiple frames are sent in rapid succession.
Fixes: f4a4cbb204 ("USB: ir-usb: reimplement using generic framework")
Cc: stable <stable@vger.kernel.org> # 2.6.35
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Commit e0d795e4f3 ("usb: irda: cleanup on ir-usb module") added a USB
IrDA header with common defines, but mistakingly switched to using the
class-descriptor baud-rate bitmask values for the outbound header.
This broke link-speed handling for rates above 9600 baud, but a device
would also be able to operate at the default 9600 baud until a
link-speed request was issued (e.g. using the TCGETS ioctl).
Fixes: e0d795e4f3 ("usb: irda: cleanup on ir-usb module")
Cc: stable <stable@vger.kernel.org> # 2.6.27
Cc: Felipe Balbi <balbi@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Add missing endpoint sanity check to avoid dereferencing a NULL-pointer
on open() in case a device lacks a bulk-out endpoint.
Note that prior to commit f4a4cbb204 ("USB: ir-usb: reimplement using
generic framework") the oops would instead happen on open() if the
device lacked a bulk-in endpoint and on write() if it lacked a bulk-out
endpoint.
Fixes: f4a4cbb204 ("USB: ir-usb: reimplement using generic framework")
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Check for NULL port data in the modem- and line-status handlers to avoid
dereferencing a NULL pointer in the unlikely case where a port device
isn't bound to a driver (e.g. after an allocation failure on port
probe).
Note that the other (stubbed) event handlers qt2_process_xmit_empty()
and qt2_process_flush() would need similar sanity checks in case they
are ever implemented.
Fixes: f7a33e608d ("USB: serial: add quatech2 usb to serial driver")
Cc: stable <stable@vger.kernel.org> # 3.5
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Check for NULL port data in the control URB completion handlers to avoid
dereferencing a NULL pointer in the unlikely case where a port device
isn't bound to a driver (e.g. after an allocation failure on port
probe()).
Fixes: 0ca1268e10 ("USB Serial Keyspan: add support for USA-49WG & USA-28XG")
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
The driver receives the active port number from the device, but never
made sure that the port number was valid. This could lead to a
NULL-pointer dereference or memory corruption in case a device sends
data for an invalid port.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Check for NULL port data in the shared interrupt and bulk completion
callbacks to avoid dereferencing a NULL pointer in case a device sends
data for a port device which isn't bound to a driver (e.g. due to a
malicious device having unexpected endpoints or after an allocation
failure on port probe).
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Check for NULL port data in reset_resume() to avoid dereferencing a NULL
pointer in case the port device isn't bound to a driver (e.g. after a
failed control request at port probe).
Fixes: 1ded7ea47b ("USB: ch341 serial: fix port number changed after resume")
Cc: stable <stable@vger.kernel.org> # 2.6.30
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Old code in the kernel uses 1-byte and 0-byte arrays to indicate the
presence of a "variable length array":
struct something {
int length;
u8 data[1];
};
struct something *instance;
instance = kmalloc(sizeof(*instance) + size, GFP_KERNEL);
instance->length = size;
memcpy(instance->data, source, size);
There is also 0-byte arrays. Both cases pose confusion for things like
sizeof(), CONFIG_FORTIFY_SOURCE, etc.[1] Instead, the preferred mechanism
to declare variable-length types such as the one above is a flexible array
member[2] which need to be the last member of a structure and empty-sized:
struct something {
int stuff;
u8 data[];
};
Also, by making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
unadvertenly introduced[3] to the codebase from now on.
[1] https://github.com/KSPP/linux/issues/21
[2] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Make sure to stop any submitted write URBs on close().
Note that the tty layer will wait up to 30 seconds for the buffers to
drain before close() is called.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Add a chars_in_buffer() implementation so that the tty layer will wait
for outgoing buffered data to be drained when needed (e.g. on final
close()).
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
USB-serial drivers must not be unbound from their ports before the
corresponding USB driver is unbound from the parent interface so
suppress the bind and unbind attributes.
Unbinding a serial driver while it's port is open is a sure way to
trigger a crash as any driver state is released on unbind while port
hangup is handled on the parent USB interface level. Drivers for
multiport devices where ports share a resource such as an interrupt
endpoint also generally cannot handle individual ports going away.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
The driver was issuing synchronous uninterruptible control requests
without using a timeout. This could lead to the driver hanging
on open() or tiocmset() due to a malfunctioning (or malicious) device
until the device is physically disconnected.
The USB upper limit of five seconds per request should be more than
enough.
Fixes: 309a057932 ("USB: opticon: add rts and cts support")
Cc: stable <stable@vger.kernel.org> # 2.6.39
Cc: Martin Jansen <martin.jansen@opticon.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Telit FN980 flashing device 0x1bc7/0x9010 requires zero packet
to be sent if out data size is is equal to the endpoint max size.
Signed-off-by: Daniele Palmas <dnlplm@gmail.com>
[ johan: switch operands in conditional ]
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Make sure to use the current alternate setting when looking up the
endpoints on epic devices to avoid binding to an invalid interface.
Failing to do so could cause the driver to misbehave or trigger a WARN()
in usb_submit_urb() that kernels with panic_on_warn set would choke on.
Fixes: 6e8cf7751f ("USB: add EPIC support to the io_edgeport driver")
Cc: stable <stable@vger.kernel.org> # 2.6.21
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191210112601.3561-5-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
$ sed -e 's/^ /\t/' -i */Kconfig
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20191121132856.29130-1-krzk@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for the Mark-10 digital force gauge device to the cp201x
driver.
Based on a report and a larger patch from Joel Jennings
Reported-by: Joel Jennings <joel.jennings@makeitlabs.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191118092119.GA153852@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are the USB-serial updates for 5.5-rc1, including:
- support for a new class of pl2303 devices
- improved divisor calculations for ch341
- fixes for a remote-wakeup bug in the moschip drivers
- improved device-type handling in mos7840
- various cleanups of mos7840
Included are also some new device ids.
All have been in linux-next with no reported issues.
Signed-off-by: Johan Hovold <johan@kernel.org>
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Merge tag 'usb-serial-5.5-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next
Johan writes:
USB-serial updates for 5.5-rc1
Here are the USB-serial updates for 5.5-rc1, including:
- support for a new class of pl2303 devices
- improved divisor calculations for ch341
- fixes for a remote-wakeup bug in the moschip drivers
- improved device-type handling in mos7840
- various cleanups of mos7840
Included are also some new device ids.
All have been in linux-next with no reported issues.
Signed-off-by: Johan Hovold <johan@kernel.org>
* tag 'usb-serial-5.5-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
USB: serial: ftdi_sio: add device IDs for U-Blox C099-F9P
USB: serial: option: add support for Foxconn T77W968 LTE modules
USB: serial: mos7840: drop port open flag
USB: serial: mos7840: drop read-urb check
USB: serial: mos7840: drop port driver data accessors
USB: serial: mos7840: drop serial struct accessor
USB: serial: mos7840: drop paranoid serial checks
USB: serial: mos7840: drop paranoid port checks
USB: serial: mos7840: drop redundant urb context check
USB: serial: mos7840: rip out broken interrupt handling
USB: serial: mos7840: fix probe error handling
USB: serial: mos7840: document MCS7810 detection hack
USB: serial: mos7840: clean up device-type handling
USB: serial: mos7840: fix remote wakeup
USB: serial: mos7720: fix remote wakeup
USB: serial: option: add support for DW5821e with eSIM support
USB: serial: mos7840: add USB ID to support Moxa UPort 2210
USB: serial: ch341: reimplement line-speed handling
USB: serial: pl2303: add support for PL2303HXN
This device presents itself as a USB hub with three attached devices:
- An ACM serial port connected to the GPS module (not affected by this
commit)
- An FTDI serial port connected to the GPS module (1546:0502)
- Another FTDI serial port connected to the ODIN-W2 radio module
(1546:0503)
This commit registers U-Blox's VID and the PIDs of the second and third
devices.
Datasheet: https://www.u-blox.com/sites/default/files/C099-F9P-AppBoard-Mbed-OS3-FW_UserGuide_%28UBX-18063024%29.pdf
Signed-off-by: Fabio D'Urso <fabiodurso@hotmail.it>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Drop the redundant port open flag and corresponding checks. USB serial
core will not call any of these driver callbacks for a closed port, and the
write URBs are stopped at close().
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Drop read-urb check which is always false from completion the callback.
The driver read-urb pointer is set at every open and is never cleared.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Drop the custom port driver data accessors and paranoid sanity checks.
The driver data is not cleared until the driver is unbound.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Drop the helper used to retrieve the serial struct pointer from the port
structure.
Note that this helper was only used when the serial structure was
actually not needed.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Drop the likewise paranoid serial structure sanity checks.
USB serial core sets the serial pointer in the port structures at
initialisation and it is never cleared, and similar for the serial
structure type.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Drop the paranoid port structure sanity checks which are confusing at
best.
The driver data port pointer is set at port probe and never cleared,
while USB serial core sets the tty driver data at install and won't call
any driver functions with a NULL port pointer.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
The bulk-in URB context is set to the driver-data struct at open and is
never cleared so drop the redundant check in the completion callback.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
The interrupt handling is completely broken and has in fact never been
been enabled due to an inverted test for an interrupt endpoint in
open() that prevented the interrupt URB from being submitted.
Other highlights include missing interrupt URB resubmission (had it
ever been submitted), missing locking when managing the open-port count,
and NULL-pointer dereferences that could have been triggered by a
malicious device.
Rip out this broken crap which is beyond repair instead of pretending
we support this feature.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
The driver would return success and leave the port structures
half-initialised if any of the register accesses during probe fails.
This would specifically leave the port control urb unallocated,
something which could trigger a NULL pointer dereference on interrupt
events.
Fortunately the interrupt implementation is completely broken and has
never even been enabled...
Note that the zero-length-enable register write used to set the zle-flag
for all ports is moved to attach.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Document the MCS7810 detection hack which relies on having the GPO and
GPI pins connected as recommended by ASIX.
Note that GPO (pin 42) is really RTS of the third port which will be
toggled for the corresponding physical port on two- and four-port
devices.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
The current device-type detection is fragile and can't really be relied
upon. Instead of sprinkling device-id conditionals throughout the
driver, let's use the device-id table to encode the number of ports and
whether the device has a driver-controlled activity LED (MCS7810).
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
The driver was setting the device remote-wakeup feature during probe in
violation of the USB specification (which says it should only be set
just prior to suspending the device). This could potentially waste
power during suspend as well as lead to spurious wakeups.
Note that USB core would clear the remote-wakeup feature at first
resume.
Fixes: 3f5429746d ("USB: Moschip 7840 USB-Serial Driver")
Cc: stable <stable@vger.kernel.org> # 2.6.19
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
The driver was setting the device remote-wakeup feature during probe in
violation of the USB specification (which says it should only be set
just prior to suspending the device). This could potentially waste
power during suspend as well as lead to spurious wakeups.
Note that USB core would clear the remote-wakeup feature at first
resume.
Fixes: 0f64478cbc ("USB: add USB serial mos7720 driver")
Cc: stable <stable@vger.kernel.org> # 2.6.19
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Add USB ID for MOXA UPort 2210. This device contains mos7820 but
it passes GPIO0 check implemented by driver and it's detected as
mos7840. Hence product id check is added to force mos7820 mode.
Signed-off-by: Pavel Löbl <pavel@loebl.cz>
Cc: stable <stable@vger.kernel.org>
[ johan: rename id defines and add vendor-id check ]
Signed-off-by: Johan Hovold <johan@kernel.org>
The current ch341 divisor algorithm was known to give inaccurate results
for certain higher line speeds. Jonathan Olds <jontio@i4free.co.nz>
investigated this, determined the basic equations used to derive the
divisors and confirmed them experimentally [1].
The equations Jonathan used could be generalised further to:
baudrate = 48000000 / (2^(12 - 3 * ps - fact) * div), where
0 <= ps <= 3,
0 <= fact <= 1,
2 <= div <= 256 if fact = 0, or
9 <= div <= 256 if fact = 1
which will also give better results for lower rates.
Notably the error is reduced for the following standard rates:
1152000 (4.0% instead of 15% error)
921600 (0.16% instead of -7.5% error)
576000 (-0.80% instead of -5.6% error)
200 (0.16% instead of -0.69% error)
134 (-0.05% instead of -0.63% error)
110 (0.03% instead of -0.44% error)
but also for many non-standard ones.
The current algorithm also suffered from rounding issues (e.g.
requesting 2950000 Bd resulted in a rate of 2 MBd instead of 3 MBd and
thus a -32% instead of 1.7% error).
The new algorithm was inspired by the current vendor driver even if that
one only handles two higher rates that require fact=1 by hard coding the
corresponding divisors [2].
Michael Dreher <michael@5dot1.de> also did a similar generalisation of
Jonathan's work and has published his results with a very good summary
that provides further insights into how this device works [3].
[1] https://lkml.kernel.org/r/000001d51f34$bad6afd0$30840f70$@co.nz
[2] http://www.wch.cn/download/CH341SER_LINUX_ZIP.html
[3] https://github.com/nospam2000/ch341-baudrate-calculation
Reported-by: Jonathan Olds <jontio@i4free.co.nz>
Tested-by: Jonathan Olds <jontio@i4free.co.nz>
Cc: Michael Dreher <michael@5dot1.de>
Signed-off-by: Johan Hovold <johan@kernel.org>
Add missing endianness conversion when setting the line speed so that
this driver might work also on big-endian machines.
Also use an unsigned format specifier in the corresponding debug
message.
Signed-off-by: Johan Hovold <johan@kernel.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191029102354.2733-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix a user-controlled slab buffer overflow due to a missing sanity check
on the bulk-out transfer buffer used for control requests.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191029102354.2733-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Prolific has developed a new USB to UART chip: PL2303HXN
PL2303HXN : PL2303GC/PL2303GS/PL2303GT/PL2303GL/PL2303GE/PL2303GB
The Vendor request used by the PL2303HXN (TYPE_HXN) is different from
the existing PL2303 series (TYPE_HX & TYPE_01).
Therefore, different Vendor requests are used to issue related commands.
1. Added a new TYPE_HXN type in pl2303_type_data, and then executes
new Vendor request,new flow control and other related instructions
if TYPE_HXN is recognized.
2. Because the new PL2303HXN only accept the new Vendor request,
the old Vendor request cannot be accepted (the error message
will be returned)
So first determine the TYPE_HX or TYPE_HXN through
PL2303_READ_TYPE_HX_STATUS in pl2303_startup.
2.1 If the return message is "1", then the PL2303 is the existing
TYPE_HX/ TYPE_01 series.
The other settings in pl2303_startup are to continue execution.
2.2 If the return message is "not 1", then the PL2303 is the new
TYPE_HXN series.
The other settings in pl2303_startup are ignored.
(PL2303HXN will directly use the default value in the hardware,
no need to add additional settings through the software)
3. In pl2303_open: Because TYPE_HXN is different from the instruction of reset
down/up stream used by TYPE_HX.
Therefore, we will also execute different instructions here.
4. In pl2303_set_termios: The UART flow control instructions used by
TYPE_HXN/TYPE_HX/TYPE_01 are different.
Therefore, we will also execute different instructions here.
5. In pl2303_vendor_read & pl2303_vendor_write, since TYPE_HXN is different
from the vendor request instruction used by TYPE_HX/TYPE_01,
it will also execute different instructions here.
6. In pl2303_update_reg: TYPE_HXN used different register for flow control.
Therefore, we will also execute different instructions here.
Signed-off-by: Charles Yeh <charlesyeh522@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Use the tdev pointer directly instead of going through the port data
when accessing the serial data in close().
Signed-off-by: Johan Hovold <johan@kernel.org>
Fix races between closing a port and opening or closing another port on
the same device which could lead to a failure to start or stop the
shared interrupt URB. The latter could potentially cause a
use-after-free or worse in the completion handler on driver unbind.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Here's a fix for a long-standing issue in the keyspan driver which could
lead to NULL-pointer dereferences when a device had unexpected endpoint
descriptors.
Included are also some new device IDs.
All but the last two commits have been in linux-next with no reported
issues.
Signed-off-by: Johan Hovold <johan@kernel.org>
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Merge tag 'usb-serial-5.4-rc2' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-linus
Johan writes:
USB-serial fixes for 5.4-rc2
Here's a fix for a long-standing issue in the keyspan driver which could
lead to NULL-pointer dereferences when a device had unexpected endpoint
descriptors.
Included are also some new device IDs.
All but the last two commits have been in linux-next with no reported
issues.
Signed-off-by: Johan Hovold <johan@kernel.org>
* tag 'usb-serial-5.4-rc2' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
USB: serial: keyspan: fix NULL-derefs on open() and write()
USB: serial: option: add support for Cinterion CLS8 devices
USB: serial: option: add Telit FN980 compositions
USB: serial: ftdi_sio: add device IDs for Sienna and Echelon PL-20
Since commit c2b71462d2 ("USB: core: Fix bug caused by duplicate
interface PM usage counter") USB drivers must always balance their
runtime PM gets and puts, including when the driver has already been
unbound from the interface.
Leaving the interface with a positive PM usage counter would prevent a
later bound driver from suspending the device.
Fixes: c2b71462d2 ("USB: core: Fix bug caused by duplicate interface PM usage counter")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191001084908.2003-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
$ sed -e 's/^ /\t/' -i */Kconfig
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20190923154956.6868-1-krzk@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix NULL-pointer dereferences on open() and write() which can be
triggered by a malicious USB device.
The current URB allocation helper would fail to initialise the newly
allocated URB if the device has unexpected endpoint descriptors,
something which could lead NULL-pointer dereferences in a number of
open() and write() paths when accessing the URB. For example:
BUG: kernel NULL pointer dereference, address: 0000000000000000
...
RIP: 0010:usb_clear_halt+0x11/0xc0
...
Call Trace:
? tty_port_open+0x4d/0xd0
keyspan_open+0x70/0x160 [keyspan]
serial_port_activate+0x5b/0x80 [usbserial]
tty_port_open+0x7b/0xd0
? check_tty_count+0x43/0xa0
tty_open+0xf1/0x490
BUG: kernel NULL pointer dereference, address: 0000000000000000
...
RIP: 0010:keyspan_write+0x14e/0x1f3 [keyspan]
...
Call Trace:
serial_write+0x43/0xa0 [usbserial]
n_tty_write+0x1af/0x4f0
? do_wait_intr_irq+0x80/0x80
? process_echoes+0x60/0x60
tty_write+0x13f/0x2f0
BUG: kernel NULL pointer dereference, address: 0000000000000000
...
RIP: 0010:keyspan_usa26_send_setup+0x298/0x305 [keyspan]
...
Call Trace:
keyspan_open+0x10f/0x160 [keyspan]
serial_port_activate+0x5b/0x80 [usbserial]
tty_port_open+0x7b/0xd0
? check_tty_count+0x43/0xa0
tty_open+0xf1/0x490
Fixes: fdcba53e2d ("fix for bugzilla #7544 (keyspan USB-to-serial converter)")
Cc: stable <stable@vger.kernel.org> # 2.6.21
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
