An attack has become available which pretends to be a quirky
device circumventing normal sanity checks and crashes the kernel
by an insufficient number of interfaces. This patch adds a check
to the code path for quirky devices.
Signed-off-by: NOliver Neukum <ONeukum@suse.com>
CC: stable@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This should cut down latencies and waste if the tty layer writes single bytes.

Signed-off-by: Oliver Neukum >oneukum@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This phone needs to be handled by a specialised firmware tool
and is reported to crash irrevocably if cdc-acm takes it.
Signed-off-by: NOliver Neukum <oneukum@suse.com>
CC: stable@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

For Intel 7260 modem, it is needed for host side to send zero
packet if the BULK OUT size is equal to USB endpoint max packet
length. Otherwise, modem side may still wait for more data and
cannot give response to host side.
Signed-off-by: NKonrad Leszczynski <konrad.leszczynski@intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In current acm driver, the bulk-in callback function ignores the
URBs unlinked in usb core.

This causes unexpected data loss in some cases. For example,
runtime suspend entry will unlinked all urbs and set urb->status
to -ENOENT even those urbs might have data not processed yet.
Hence, data loss occurs.

This patch lets bulk-in callback function handle unlinked urbs
to avoid data loss.
Signed-off-by: NTang Jian Qiang <jianqiang.tang@intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Cc: stable@vger.kernel.org
Acked-by: NOliver Neukum <oneukum@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Some modems, such as the Telit UE910, are using an Infineon Flash Loader
utility. It has two interfaces, 2/2/0 (Abstract Modem) and 10/0/0 (CDC
Data). The latter can be used as a serial interface to upgrade the
firmware of the modem. However, that isn't possible when the cdc-acm
driver takes control of the device.

The following is an explanation of the behaviour by Daniele Palmas during
discussion on linux-usb.

"This is what happens when the device is turned on (without modifying
the drivers):

[155492.352031] usb 1-3: new high-speed USB device number 27 using ehci-pci
[155492.485429] usb 1-3: config 1 interface 0 altsetting 0 endpoint 0x81 has an invalid bInterval 255, changing to 11
[155492.485436] usb 1-3: New USB device found, idVendor=058b, idProduct=0041
[155492.485439] usb 1-3: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[155492.485952] cdc_acm 1-3:1.0: ttyACM0: USB ACM device

This is the flashing device that is caught by the cdc-acm driver. Once
the ttyACM appears, the application starts sending a magic string
(simple write on the file descriptor) to keep the device in flashing
mode. If this magic string is not properly received in a certain time
interval, the modem goes on in normal operative mode:

[155493.748094] usb 1-3: USB disconnect, device number 27
[155494.916025] usb 1-3: new high-speed USB device number 28 using ehci-pci
[155495.059978] usb 1-3: New USB device found, idVendor=1bc7, idProduct=0021
[155495.059983] usb 1-3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[155495.059986] usb 1-3: Product: 6 CDC-ACM + 1 CDC-ECM
[155495.059989] usb 1-3: Manufacturer: Telit
[155495.059992] usb 1-3: SerialNumber: 359658044004697
[155495.138958] cdc_acm 1-3:1.0: ttyACM0: USB ACM device
[155495.140832] cdc_acm 1-3:1.2: ttyACM1: USB ACM device
[155495.142827] cdc_acm 1-3:1.4: ttyACM2: USB ACM device
[155495.144462] cdc_acm 1-3:1.6: ttyACM3: USB ACM device
[155495.145967] cdc_acm 1-3:1.8: ttyACM4: USB ACM device
[155495.147588] cdc_acm 1-3:1.10: ttyACM5: USB ACM device
[155495.154322] cdc_ether 1-3:1.12 wwan0: register 'cdc_ether' at usb-0000:00:1a.7-3, Mobile Broadband Network Device, 00:00:11:12:13:14

Using the cdc-acm driver, the string, though being sent in the same way
than using the usb-serial-simple driver (I can confirm that the data is
passing properly since I used an hw usb sniffer), does not make the
device to stay in flashing mode."
Signed-off-by: NJonas Jonsson <jonas@ludd.ltu.se>
Tested-by: NDaniele Palmas <dnlplm@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NJohan Hovold <johan@kernel.org>

Destroy acm_minors IDR on module exit, reclaiming the allocated memory.

This was detected by the following semantic patch (written by Luis Rodriguez
<mcgrof@suse.com>)
<SmPL>
@ defines_module_init @
declarer name module_init, module_exit;
declarer name DEFINE_IDR;
identifier init;
@@

module_init(init);

@ defines_module_exit @
identifier exit;
@@

module_exit(exit);

@ declares_idr depends on defines_module_init && defines_module_exit @
identifier idr;
@@

DEFINE_IDR(idr);

@ on_exit_calls_destroy depends on declares_idr && defines_module_exit @
identifier declares_idr.idr, defines_module_exit.exit;
@@

exit(void)
{
 ...
 idr_destroy(&idr);
 ...
}

@ missing_module_idr_destroy depends on declares_idr && defines_module_exit && !on_exit_calls_destroy @
identifier declares_idr.idr, defines_module_exit.exit;
@@

exit(void)
{
 ...
 +idr_destroy(&idr);
 }
</SmPL>
Signed-off-by: NJohannes Thumshirn <jthumshirn@suse.de>
Acked-by: NOliver Neukum <oneukum@suse.com>
Acked-by: NJohan Hovold <johan@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

ATOL FPrint fiscal printers require usb_clear_halt to be executed
to work properly. Add quirk to fix the issue.
Signed-off-by: NAlexey Sokolov <sokolov@7pikes.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use kernel.h macro definition.
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Acked-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use the idr-interface rather than a static table to manage minor-number
allocations.

This allows us to easily switch over to fully dynamic minor allocations
when the TTY-layer can handle that.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Acked-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Phil and I found out a problem with commit:

  7e860a6e ("cdc-acm: add sanity checks")

It added some sanity checks to ignore potential garbage in CDC headers but
also introduced a potential infinite loop.  This can happen at the first
loop iteration (elength = 0 in that case) if the description isn't a
DT_CS_INTERFACE or later if 'buffer[0]' is zero.

It should also be noted that the wrong length was being added to 'buffer'
in case 'buffer[1]' was not a DT_CS_INTERFACE descriptor, since elength was
assigned after that check in the loop.

A specially crafted USB device could be used to trigger this infinite loop.

Fixes: 7e860a6e ("cdc-acm: add sanity checks")
Signed-off-by: NPhil Turnbull <phil.turnbull@oracle.com>
Signed-off-by: NQuentin Casasnovas <quentin.casasnovas@oracle.com>
CC: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
CC: Oliver Neukum <oneukum@suse.de>
CC: Adam Lee <adam8157@gmail.com>
CC: <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

A step on the road to passing status as a parameter
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

During the entry intro suspend a misleading message can be
printed. Surpress it by checking the specific error.

Signed-off-by: Oliver Neukum <oneukum@suse.de>0
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Abn URB may be may marked free only after the buffer has been
processed or there is a small window during which it could
be submitted on another CPU and overwrite an unprocessed buffer
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In order to support an older USB cradle by Denso, I added its vendor- and product-ID to the array of usb_device_id acm_ids. In this way cdc-acm feels responsible for this cradle. The related /dev/ttyACM node is being created properly, and the data transfer works.

However, later cradle models by Denso do have proper descriptors, so the patch is not required for these. At the same time both the older and the later model have the same vendor- and product-ID, but they both work with the patched driver.

Declaration of the Denso cradles I tested:
- both models have the same IDs: vendorID 0x076d, productID 0x0006
- older model: Denso CU-321 (descriptors not properly set)
- later model: Denso CU-821 (with proper descriptors)
Signed-off-by: NBjoern Gerhart <oss@airbjorn.de>
Acked-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Memory allocation failures are reported by a central facility.
No need to repeat the job.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Check the special CDC headers for a plausible minimum length.
Another big operating systems ignores such garbage.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
CC: stable@vger.kernel.org
Reviewed-by: NAdam Lee <adam8157@gmail.com>
Tested-by: NAdam Lee <adam8157@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We need to check that we have both a valid data and control inteface for both
types of headers (union and not union.)

References: https://bugzilla.kernel.org/show_bug.cgi?id=83551Reported-by: NSimon Schubert <2+kernel@0x2c.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If probe() fails not only the attributes need to be removed
but also the memory freed.
Reported-by: NAhmed Tamrawi <ahmedtamrawi@gmail.com>
Signed-off-by: NOliver Neukum <oneukum@suse.de>
CC: stable@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add new quirk for devices that cannot handle control-line state
requests.

Note that we currently send these requests to all devices, regardless of
whether they claim to support it, but that errors are only logged if
support is claimed.

Since commit 0943d8ea ("USB: cdc-acm: use tty-port dtr_rts"), which
only changed the timings for these requests slightly, this has been
reported to cause occasional firmware crashes on Simtec Electronics
Entropy Key devices after re-enumeration. Enable the quirk for this
device.
Reported-by: NNix <nix@esperi.org.uk>
Tested-by: NNix <nix@esperi.org.uk>
Cc: stable <stable@vger.kernel.org>	# v3.16
Signed-off-by: NJohan Hovold <johan@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Make sure to only raise DTR on transitions from B0 in set_termios.

Also allow set_termios to be called from open with a termios_old of
NULL. Note that DTR will not be raised prematurely in this case.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: NJohan Hovold <johan@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Let's drop the warning for modems with unusual capabilities,
the associated quirk and blacklist. They made little sense.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver wasn't properly configuring the hardware for the current
termios settings under all conditions.  Ensure that termios are
written to the device when the port is activated.
Signed-off-by: NJim Paris <jim@jtan.com>
Reviewed-by: NJohan Hovold <johan@kernel.org>
Acked-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add device-id entry for GW Instek AFG-2225, which has a byte swapped
bInterfaceSubClass (0x20).
Reported-by: NKarl Palsson <karlp@tweak.net.au>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NJohan Hovold <johan@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add dtr_rts tty-port operation which implements proper DTR/RTS handling
(e.g. only lower DTR/RTS during shutdown if HUPCL is set).

Note that modem-control locking still needs to be added throughout the
driver.
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There's no need to call usb_mark_last_busy after having increased the PM
counter in write(). The device will be marked busy by USB core when the
PM counter is balanced in the completion handler.
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There's no need to update the runtime PM last_busy field on read urb
errors (e.g. when the urb is being killed on shutdown).
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Now that acm_set_control() handles runtime PM properly, the only
remaining reason for the PM operations in shutdown is to clear the
needs_remote_wakeup flag before the final put.

Note that this also means that we now need to grab the write_lock to
prevent racing with resume.
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove redundant disconnect test from shutdown(), which is never called
post disconnect() where we do synchronous hangup.
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We can simply the runtime PM locking as there's no need to check the
susp_count in the read path (at least not since killing the rx tasklet).

Specifically, the read urbs will never be resubmitted by the completion
handler when killed during suspend.
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Make sure only to decrement the PM counters if they were actually
incremented.

Note that the USB PM counter, but not necessarily the driver core PM
counter, is reset when the interface is unbound.

Fixes: 11ea859d ("USB: additional power savings for cdc-acm devices
that support remote wakeup")
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Make sure to kill any already submitted read urbs on read-urb submission
failures in open in order to prevent doing I/O for a closed port.

Fixes: 088c64f8 ("USB: cdc-acm: re-write read processing")
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix errors during open not being returned to userspace. Specifically,
failed control-line manipulations or control or read urb submissions
would not be detected.

Fixes: 7fb57a01 ("USB: cdc-acm: Fix potential deadlock (lockdep
warning)")
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We must not do the usb_autopm_put_interface() before submitting the read
urbs or we might end up doing I/O to a suspended device.

Fixes: 088c64f8 ("USB: cdc-acm: re-write read processing")
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Make sure to check return value of autopm get in write() in order to
avoid urb leak and PM counter imbalance on errors.

Fixes: 11ea859d ("USB: additional power savings for cdc-acm devices
that support remote wakeup")

Cc: <stable@vger.kernel.org>	# v2.6.27
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We should stop I/O unconditionally at suspend rather than rely on the
tty-port initialised flag (which is set prior to stopping I/O during
shutdown) in order to prevent suspend returning with URBs still active.

Fixes: 11ea859d ("USB: additional power savings for cdc-acm devices
that support remote wakeup")

Cc: <stable@vger.kernel.org>	# v2.6.27
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix runtime PM handling of control messages by adding the required PM
counter operations.

Fixes: 11ea859d ("USB: additional power savings for cdc-acm devices
that support remote wakeup")

Cc: <stable@vger.kernel.org>	# v2.6.27
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The current ACM runtime-suspend implementation is broken in several
ways:

Firstly, it buffers only the first write request being made while
suspended -- any further writes are silently dropped.

Secondly, writes being dropped also leak write urbs, which are never
reclaimed (until the device is unbound).

Thirdly, even the single buffered write is not cleared at shutdown
(which may happen before the device is resumed), something which can
lead to another urb leak as well as a PM usage-counter leak.

Fix this by implementing a delayed-write queue using urb anchors and
making sure to discard the queue properly at shutdown.

Fixes: 11ea859d ("USB: additional power savings for cdc-acm devices
that support remote wakeup")
Reported-by: NXiao Jin <jin.xiao@intel.com>
Cc: <stable@vger.kernel.org>	# v2.6.27
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix race between write() and resume() due to improper locking that could
lead to writes being reordered.

Resume must be done atomically and susp_count be protected by the
write_lock in order to prevent racing with write(). This could otherwise
lead to writes being reordered if write() grabs the write_lock after
susp_count is decremented, but before the delayed urb is submitted.

Fixes: 11ea859d ("USB: additional power savings for cdc-acm devices
that support remote wakeup")

Cc: <stable@vger.kernel.org>	# v2.6.27
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix race between write() and suspend() which could lead to writes being
dropped (or I/O while suspended) if the device is runtime suspended
while a write request is being processed.

Specifically, suspend() releases the write_lock after determining the
device is idle but before incrementing the susp_count, thus leaving a
window where a concurrent write() can submit an urb.

Fixes: 11ea859d ("USB: additional power savings for cdc-acm devices
that support remote wakeup")

Cc: <stable@vger.kernel.org>        # v2.6.27
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>