Here are some small tty/serial driver fixes for 7.3-rc6. Nothing major
here, just lots of small fixes for reported issues, some of them very
long-standing:
- tty hangup fixes that have been there since the BKL days and kept
tripping people up over time.
- vt selection bugfix
- other vt bugfixes (memory leaks and screen update fixes)
- n_gsm bugfix
- qcom-geni serial driver bugfix
- 8250 serial driver bugfixes
- other tiny serial driver fixes
All of these have been in linux-next, the last few only a few days but
testing here seems solid (this pull request was generated on that tree)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-7.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are some small tty/serial driver fixes for 7.3-rc6. Nothing major
here, just lots of small fixes for reported issues, some of them very
long-standing:
- tty hangup fixes that have been there since the BKL days and kept
tripping people up over time.
- vt selection bugfix
- other vt bugfixes (memory leaks and screen update fixes)
- n_gsm bugfix
- qcom-geni serial driver bugfix
- 8250 serial driver bugfixes
- other tiny serial driver fixes
All of these have been in linux-next, the last few only a few days but
testing here seems solid (this pull request was generated on that
tree)"
* tag 'tty-7.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (37 commits)
tty: add missing driver flag kernel-doc colon
vt: selection: Fix unsigned underflow and slab-out-of-bounds read in paste_selection()
vt: skip screen update for DEC alignment test on backgroup consoles
vc_screen: reload vc pointer before if (ret) in vcs_write() to avoid UAF
serial: sc16is7xx: reduce TX refill rate with half-FIFO trigger
serial: sc16is7xx: refill TX FIFO below trigger using fresh TXLVL
serial: tegra: don't clear the Tx FIFO on an Rx-only reset
serial: sc16is7xx: fix TX gap caused by kfifo circular buffer wrap-around
tty: fix saved termios reset race
tty: serial: mpc52xx_uart: move static declarations up.
tty: serial: max3100: shut down timer before freeing port
tty: add break_wait kernel-doc
serial: qcom-geni: keep registered console runtime active
serial: qcom-geni: Fix unbalanced runtime PM resume for no_console_suspend
serial: qcom-geni: avoid unused-function warning
tty: serial: qcom_geni_serial: Keep console RX functional after deep idle
soc: qcom: geni-se: Correct QUP Core ICC vote constants
serial: 8250_bcm7271: fix use-after-free in brcmuart_remove()
serial: vt8500: Fix clock reference leak in vt8500_serial_probe()
kgdboc: Fix tty driver reference leak in configure_kgdboc()
...
Resetting saved termios state on device registration is needed where a
minor number can be reused for an entirely different device and where
the old settings may prevent the port from even being opened (e.g. when
CLOCAL is not set).
Not all TTY drivers guarantee that the minor number is no longer in use
when registering devices however, something which can lead to a
use-after-free when closing a TTY (and saving its termios) races with
re-registration.
Add a new TTY_DRIVER_RESET_SAVED_TERMIOS flag to request that any saved
termios state is reset on registration and only set it for drivers that
make sure that the minor number is no longer in use.
Fixes: 93857edd98 ("tty: reset termios state on device registration")
Reported-by: Chengfeng Ye <nicoyip.dev@gmail.com>
Link: https://lore.kernel.org/20260926184154.3017929-1-nicoyip.dev@gmail.com
Cc: stable@kernel.org # 4.12
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20260930131845.1809256-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The requested baud rate is incorrectly truncated to 16 bits so that
line speeds above 65535 bps cannot be set.
Use 32 bits for the rate while rejecting rates outside of
[50,921600] to avoid having the 16-bit divisor overflow.
Fixes: f7a33e608d ("USB: serial: add quatech2 usb to serial driver")
Cc: stable@vger.kernel.org # 3.5
Cc: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Johan Hovold <johan@kernel.org>
The requested baud rate is incorrectly truncated to 16 bits so that
line speeds above 65535 bps cannot be set.
Use 32 bits for the rate and remainder while rejecting rates outside of
[50,460800] to avoid having the divisor or remainder overflow.
This issue was flagged by an LLM.
Fixes: 52af954599 ("USB: add USB serial ssu100 driver")
Cc: stable@vger.kernel.org # 2.6.36
Cc: Bill Pemberton <wfp5p@virginia.edu>
Assisted-by: LLM
Signed-off-by: Johan Hovold <johan@kernel.org>
The Corsair AX1500i power supply exposes its Corsair Link monitoring
interface on a mini-USB port through an on-board CP2103, using a
Corsair-specific product ID. Without the ID in the table no driver binds
and no tty is created.
Tested by forcing the driver association with
echo 1b1c 1c02 > /sys/bus/usb-serial/drivers/cp210x/new_id
and then setting the serial port to 115200 8N1. Adding the ID is sufficient
to talk to the device: the tty reaches a USB-to-SMBus bridge sitting behind
the UART, which identifies itself as "USB to SMB Bridge (Firmware by Ross
Fosler)" version 0.9 and relays PMBus reads to the power supply controller.
Input voltage and current, input and output power, internal temperature and
fan speed were all read back on an AX1500i.
[ 7.806181] usb 3-14: New USB device found, idVendor=1b1c, idProduct=1c02, bcdDevice= 1.00
[ 698.526754] usbcore: registered new interface driver cp210x
[ 698.526767] usbserial: USB Serial support registered for cp210x
[ 698.527863] cp210x 3-14:1.0: cp210x converter detected
[ 698.529263] usb 3-14: cp210x converter now attached to ttyUSB0
The related AX1600i (1b1c:1c11, iProduct "USB API") is expected to be the
same kind of device but has not been tested here, so it is not added.
Cc: stable@vger.kernel.org
Signed-off-by: Jérémy Carrat <jeremy.carrat@icloud.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Use the new serial driver iterator variable also when deregistering
serial drivers to improve readability.
Signed-off-by: Johan Hovold <johan@kernel.org>
USB serial driver modules register one driver for the USB bus and one or
more drivers for the ports on the USB serial bus.
When unloading a driver module, the USB driver must be deregistered
before the USB serial bus drivers so that I/O is stopped before
unbinding the ports to avoid use-after-free in completion handlers
accessing port data.
Note that the "new_id" attributes must first be removed to prevent new
ids from being added and triggering a probe of the USB driver after it
has been deregistered.
Fixes: 765e0ba626 ("usb-serial: new API for driver registration")
Cc: stable@vger.kernel.org # 3.4
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Johan Hovold <johan@kernel.org>
Only free the dynamic ids after having deregistered the driver and
removed the "new_id" attribute to avoid leaking any id added by a racing
write to the attribute.
Fixes: 93bacefc4c ("USB serial: add dynamic id support to usb-serial core")
Cc: stable@vger.kernel.org # 2.6.21
Signed-off-by: Johan Hovold <johan@kernel.org>
Some drivers for multiport devices access port driver data from
completion handlers of shared URBs submitted at attach() or first open()
and stopped at disconnect() or last close(), respectively.
A simple NULL check before accessing the driver data makes sure that a
port state container has at least been allocated, but a completion
handler can still race with port tear down.
Reorder the disconnect handling so that ports are not deregistered (and
their driver data freed) until after all ports have been hung up and the
driver disconnect() callback has run so that all I/O has been stopped.
Fixes: 2d93148ab6 ("USB: serial: fix lifetime and locking problems")
Reported-by: syzbot+e5e28c3e953b2eebb16e@syzkaller.appspotmail.com
Link: https://lore.kernel.org/all/6a7e6fb9.ec5dc6cc.21cb3f.00c0.GAE@google.com/
Cc: stable@vger.kernel.org # 2.6.30
Cc: Alan Stern <stern@rowland.harvard.edu>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Here are the USB serial updates for 7.3-rc1, including:
- fix digi_acceleport port registration order
- stop digi_acceleport I/O when ports are closed
- fix digi_acceleport OOB port dev_printk()
- fix metro-usb unthrottle race
- fix option slab OOB read with malicious devices
- add support for a new class of Prolific PL256X devices
Included are also various clean ups.
All have been in linux-next with no reported issues.
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Merge tag 'usb-serial-7.3-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next
Johan writes:
USB serial updates for 7.3-rc1
Here are the USB serial updates for 7.3-rc1, including:
- fix digi_acceleport port registration order
- stop digi_acceleport I/O when ports are closed
- fix digi_acceleport OOB port dev_printk()
- fix metro-usb unthrottle race
- fix option slab OOB read with malicious devices
- add support for a new class of Prolific PL256X devices
Included are also various clean ups.
All have been in linux-next with no reported issues.
* tag 'usb-serial-7.3-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
USB: serial: pl2303: add support for PL256X multi-port devices
USB: serial: option: fix slab OOB read in interrupt URB callback
USB: serial: keyspan_pda: drop unused driver data usb-serial pointer
USB: serial: metro-usb: drop redundant initialisations
USB: serial: metro-usb: fix unthrottle race
USB: serial: metro-usb: replace unnecessary atomic allocation
USB: serial: digi_acceleport: fix oob port dev_printk()
USB: serial: digi_acceleport: clean up inb command submission
USB: serial: digi_acceleport: clean up write completion
USB: serial: digi_acceleport: clean up xfer buf length expression
USB: serial: digi_acceleport: drop unused in-buf define
USB: serial: digi_acceleport: stop OOB I/O when not in use
USB: serial: digi_acceleport: drop redundant driver data sanity checks
USB: serial: digi_acceleport: clean up declarations and whitespace
USB: serial: digi_acceleport: add oob port helper
USB: serial: digi_acceleport: always stop write urb on close
USB: serial: digi_acceleport: drop unused wait queue
USB: serial: digi_acceleport: fix port registration order
USB: serial: digi_acceleport: do not log stopping of urbs as errors
Here is a fix for a long-standing issue in the spcp8x5 driver which
syzbot just started hitting and a change adding lockdep annotation to
digi_acceleport to suppress a false positive deadlock warning.
Note that only the digi_acceleport commit has been in linux-next (and
with no reported issues).
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Merge tag 'usb-serial-7.2-rc7' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next
Johan writes:
USB serial fixes for 7.2-rc7
Here is a fix for a long-standing issue in the spcp8x5 driver which
syzbot just started hitting and a change adding lockdep annotation to
digi_acceleport to suppress a false positive deadlock warning.
Note that only the digi_acceleport commit has been in linux-next (and
with no reported issues).
* tag 'usb-serial-7.2-rc7' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
USB: serial: spcp8x5: drop broken carrier detect support
USB: serial: digi_acceleport: add port lock nesting annotation
The driver does not support modem status notifications and instead used
to fetch the modem status once at open() and subsequently operate on and
report stale state.
As part of fixing this, a call to fetch the status was added to
carrier_raised(), which does not work as that callback must not sleep
(e.g. unlike tiocmget()).
Drop the broken carrier detect support.
Fixes: e1ed212d85 ("USB: spcp8x5: add proper modem-status support")
Cc: stable@vger.kernel.org # 3.10
Reported-by: syzbot+3b514b87202742f22c44@syzkaller.appspotmail.com
Link: https://lore.kernel.org/all/6a73cea2.01d0871a.3a0d52.000d.GAE@google.com
Signed-off-by: Johan Hovold <johan@kernel.org>
Prolific PL256X devices are multi-port USB-to-UART controllers,
including the PL2533, PL2543 and PL2565 variants.
These devices use vendor requests that differ from those used by the
existing TYPE_HX and TYPE_HXN devices. They also require a separate UART
reset request and use a port-specific register for configuring flow
control.
Add a new TYPE_MP device type and select the appropriate vendor requests,
reset operation and flow-control register for PL256X devices. Store the
USB interface number so that requests can be directed to the corresponding
UART port.
Detect the supported PL256X variants using bcdDevice before issuing any
legacy vendor requests, as PL256X devices do not accept those requests.
PL256X devices support baud rates up to 24 Mbps and do not use divisor
encoding.
Signed-off-by: Charles Yeh <charlesyeh522@gmail.com>
Link: https://lore.kernel.org/all/CAAZvQQ6O4p35Xs2hVYaoJxD4D7U0YonsdweuPh6W8RQVhvoUNw@mail.gmail.com/
Signed-off-by: Johan Hovold <johan@kernel.org>
The interrupt URB buffer is allocated in setup_port_interrupt_in() based
on the endpoint's wMaxPacketSize:
buffer_size = usb_endpoint_maxp(epd);
port->interrupt_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
When a USB device declares wMaxPacketSize = 8 on its interrupt IN
endpoint, the buffer is allocated from kmalloc-8 cache (exactly
8 bytes).
If the device sends a short packet (actual_length < wMaxPacketSize),
the URB completes with status == 0 and the callback proceeds to read:
data[sizeof(struct usb_ctrlrequest)]
which evaluates to data[8], accessing 1 byte beyond the allocated 8-byte
buffer. This results in a slab out-of-bounds read.
Fix this by adding the missing bounds check: first verify that the
actual length is large enough to contain the struct usb_ctrlrequest
header before accessing req_pkt->bRequestType and req_pkt->bRequest,
and then verify that there is an additional byte for the modem signal
state before reading data[sizeof(struct usb_ctrlrequest)] inside the
conditional. Use sizeof(*req_pkt) instead of sizeof(struct
usb_ctrlrequest) for consistency.
Assisted-by: Claude:deepseek-v4-pro
Signed-off-by: Jiale Yao <yaojiale02@163.com>
Fixes: 58cfe9113e ("[PATCH] USB: add Option Card driver")
Cc: stable@vger.kernel.org # v2.6.12
[ johan: use dev_err(); split signals declaration and initialisation ]
Signed-off-by: Johan Hovold <johan@kernel.org>
The interrupt-status packet reports transmit credits returned by the
device. edge_interrupt_callback() adds the 16-bit value to txCredits
without checking maxTxCredits.
edge_write() uses txCredits minus the software FIFO count as the amount
of data that fits. Since the FIFO is allocated with maxTxCredits bytes,
txCredits exceeding maxTxCredits can cause OOB write in ring buffer.
Cap accumulated credits at maxTxCredits. Conforming devices should never
hit the cap.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Assisted-by: Codex:GPT-5
Signed-off-by: Sunho Park <shpark061104@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
do_boot_mode() copies the firmware payload, excluding its four-byte prefix,
into a fixed 15.5 KiB staging buffer. check_fw_sanity() already proves that
the image contains its seven-byte header and validates the declared image
length and checksum, but it does not impose this boot-mode destination
limit.
Reject images whose payload does not fit before allocating and filling the
staging buffer.
Fixes: d12b219a22 ("edgeport-ti: use request_firmware()")
Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Signed-off-by: Johan Hovold <johan@kernel.org>
mxuport_probe() reads version bytes at fixed offsets after
request_firmware() succeeds. Firmware loading success does not prove that
the blob reaches the highest version offset.
Reject short firmware images before reading the version bytes. This is
source-level parser hardening; no affected device or crash was observed.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Fixes: ee467a1f20 ("USB: serial: add Moxa UPORT 12XX/14XX/16XX driver")
Signed-off-by: Johan Hovold <johan@kernel.org>
The Commubox FXA291 by Endress+Hauser AG is a USB serial converter
based on FT232B which is used to communicate with field devices.
It enumerates using the FTDI vendor ID and a custom PID.
usb 1-9: New USB device found, idVendor=0403, idProduct=e510, bcdDevice= 4.00
usb 1-9: New USB device strings: Mfr=1, Product=2, SerialNumber=0
usb 1-9: Product: FXA291
usb 1-9: Manufacturer: Endress+Hauser
usb 1-9: SerialNumber: 00000000
ftdi_sio 1-9:1.0: FTDI USB Serial Device converter detected
usb 1-9: Detected FT232B
usb 1-9: FTDI USB Serial Device converter now attached to ttyUSB0
Signed-off-by: Tim Pambor <timpambor@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
Killing the interrupt-in urb when the line disciple requests throttling
may lead to data loss if an ongoing transfer is cancelled.
Instead set a flag to prevent the completion handler from resubmitting
the urb until the port is unthrottled.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
The driver data usb-serial pointer is unused since commit 66c32e4833
("USB: serial: keyspan_pda: drop redundant usb-serial pointer"), which
apparently failed to remove the pointer as intended.
Signed-off-by: Johan Hovold <johan@kernel.org>
Three functions are initialising their return value variables at
declaration only to later assign them unconditionally.
Signed-off-by: Johan Hovold <johan@kernel.org>
If the completion handler races with unthrottle() both functions may try
to resubmit the same interrupt-in urb, but at most one will succeed.
Fix the unthrottle logic using a throttle-requested flag so that only
one attempt to resubmit the urb is made to avoid logging an error.
Fixes: 43d186fe99 ("USB: serial: add metro-usb driver to the tree")
Signed-off-by: Johan Hovold <johan@kernel.org>
The unthrottle callback is allowed to sleep so pass the correct GFP flag
to usb_submit_urb() to avoid unnecessary atomic allocations.
Signed-off-by: Johan Hovold <johan@kernel.org>
The OOB port is not registered with driver core and does not have a
name.
Use the USB interface with dev_printk() that may involve the OOB port to
avoid log entries with no driver and a "null" device name.
Fixes: f9dfbebb8b ("USB: serial: digi_acceleport.c: remove dbg() usage")
Fixes: 194343d936 ("USB: remove use of err() in drivers/usb/serial")
Signed-off-by: Johan Hovold <johan@kernel.org>
Clean up the inb command handling a bit by removing an unnecessary line
break and moving the assignment operator before breaking another long
expression.
Signed-off-by: Johan Hovold <johan@kernel.org>
Clean up the write completion handler by adding a temporary variable for
the transfer buffer and using the pre-existing urb pointer while
dropping some redundant casts.
Signed-off-by: Johan Hovold <johan@kernel.org>
Add the missing space around operators in transfer-buffer length
expressions to make the code more readable.
Signed-off-by: Johan Hovold <johan@kernel.org>
Drop the in-buf size define which has not been used since the port
buffers were removed by commit 5fea2a4dab ("USB: digi_acceleport
further buffer clean up").
Signed-off-by: Johan Hovold <johan@kernel.org>
The driver submits the OOB read urb on first open of a port and does not
stop it until the device is disconnected.
Add an open counter and submit the urb on first open and stop it on last
close to avoid wasting resources (e.g. power) when the device is not in
use.
Signed-off-by: Johan Hovold <johan@kernel.org>
The urb context pointer does not change while an urb is in flight so
there is never a need to check for NULL on completion.
The port driver data is not freed until the port is unbound at which
point all I/O for that port has been stopped (and I/O is no longer
started for a port that has not yet been probed).
The device driver data is not freed until after the driver has been
unbound and at which point all I/O has also ceased.
Drop the redundant, overly defensive (and still incomplete) sanity
checks from the completion callbacks.
Signed-off-by: Johan Hovold <johan@kernel.org>
Clean up the driver by moving some declarations to approximate reverse
xmas style and removing some stray newlines (and adding a few for
readability).
While at it, also replace two spaces before tabs in the driver structs.
Signed-off-by: Johan Hovold <johan@kernel.org>
Explicitly stop the write urb on close() also if the device is being
unbound instead of relying on core to do it after returning.
Note that the dp_write_urb_in_use flag is cleared by the completion
handler.
Signed-off-by: Johan Hovold <johan@kernel.org>
Drop the close wait queue which has not been used since commit
335f8514f2 ("tty: Bring the usb tty port structure into more use").
Signed-off-by: Johan Hovold <johan@kernel.org>
The driver submits the read urbs for all ports when the first port is
opened, which could happen before the other ports have been probed and
their private data set up.
If such an urb completes before the port has been probed, the completion
handler will not resubmit it, thus preventing any further reads.
Fix the ordering issue by not submitting the port read urbs until the
port is opened.
This also avoids wasting resources (e.g. power) when ports are not in
use.
Note that the port write urbs are already stopped on close (unless
unbinding, but they are also stopped by core on disconnect).
Fixes: fb44ff854e ("USB: digi_acceleport: fix port-data memory leak")
Signed-off-by: Johan Hovold <johan@kernel.org>
Stopping an urb is not an error and should not be logged as such.
Demote the dev_err() in the read bulk completion handler to dev_dbg()
when an urb is being unlinked on disconnect.
Note that this will become more of an issue when the urbs are stopped
every time a port is closed.
This issue was flagged by Sashiko when reviewing the upcoming change.
Link: https://sashiko.dev/#/patchset/20260623150826.314727-1-johan%40kernel.org?part=2
Signed-off-by: Johan Hovold <johan@kernel.org>
USB probe functions should not keep usb_device_id for longer than probe due
to presence of dynamic ID removal. USB serial does not support ID removal,
however in this case only driver_data is ever needed, there is no reason
keeping the usb_device_id in the first place, so convert it as well.
Reviewed-by: Manuel Ebner <manuelebner@mailbox.org>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260707-usb_dyn_id_uaf-v2-3-632dcf3adfba@garyguo.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The write() callback is supposed to return the number of characters
accepted or a negative errno. Since the addition of write fifo support
the keyspan_pda implementation will however return the number characters
submitted to the device if the write urb is not already in use. If this
number is larger than the number of characters passed to write(), the
line discipline continues writing data from beyond the tty write buffer.
Fix the information leak by making sure that keyspan_pda_write_start()
returns zero on success as intended.
Fixes: 034e38e8f6 ("USB: serial: keyspan_pda: add write-fifo support")
Cc: stable@vger.kernel.org # 5.11
Signed-off-by: Johan Hovold <johan@kernel.org>
If the port is closed while throttled, the read urb is never resubmitted
and the port will not receive any further data until the device is
reconnected (or the driver is rebound).
Clear the throttle flags and submit the urb if needed when opening the
port.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>