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>
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
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>
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>
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>
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>
