Commit Graph

12 Commits

Author SHA1 Message Date
Johan Hovold
b59dc14b0b serdev: ttyport: enforce tty-driver open() requirement
[ Upstream commit dee7d0f3b2 ]

The tty-driver open routine is mandatory, but the serdev
tty-port-controller implementation did not treat it as such and would
instead fall back to calling tty_port_open() directly.

Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20 10:10:33 +01:00
Johan Hovold
ce42ed5ae8 serdev: ttyport: fix tty locking in close
commit 90dbad8cd6 upstream.

Make sure to hold the tty lock as required when calling tty-driver
close() (e.g. to avoid racing with hangup()).

Note that the serport active flag is currently set under the lock at
controller open, but really isn't protected by it.

Fixes: cd6484e183 ("serdev: Introduce new bus for serial attached devices")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-14 09:52:44 +01:00
Johan Hovold
5a3da8bd93 serdev: ttyport: fix NULL-deref on hangup
commit 8bcd4e6a8d upstream.

Make sure to use a properly refcounted tty_struct in write_wake up to
avoid dereferencing a NULL-pointer when a port is being hung up.

Fixes: bed35c6dfa ("serdev: add a tty port controller driver")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-14 09:52:44 +01:00
Johan Hovold
d415ccdd0b serdev: ttyport: add missing receive_buf sanity checks
commit eb28168362 upstream.

The receive_buf tty-port callback should return the number of bytes
accepted and must specifically never return a negative errno (or a value
larger than the buffer size) to the tty layer.

A serdev driver not providing a receive_buf callback would currently
cause the flush_to_ldisc() worker to spin in a tight loop when the tty
buffer pointers are incremented with -EINVAL (-22) after data has been
received.

A serdev driver occasionally returning a negative errno (or a too large
byte count) could cause information leaks or crashes when accessing
memory outside the tty buffers in consecutive callbacks.

Fixes: cd6484e183 ("serdev: Introduce new bus for serial attached devices")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-14 09:52:44 +01:00
Greg Kroah-Hartman
aa668632ae Merge 4.12-rc3 into tty-next
We need the tty fixes/changes here to handle future work.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-29 08:18:15 +02:00
Johan Hovold
8cde11b2ba tty/serdev: add serdev registration interface
Add a new interface for registering a serdev controller and clients, and
a helper function to deregister serdev devices (or a tty device) that
were previously registered using the new interface.

Once every driver currently using the tty_port_register_device() helpers
have been vetted and converted to use the new serdev registration
interface (at least for deregistration), we can move serdev registration
to the current helpers and get rid of the serdev-specific functions.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 17:38:24 +02:00
Johan Hovold
aee5da7838 serdev: fix tty-port client deregistration
The port client data must be set when registering the serdev controller
or client deregistration will fail (and the serdev devices are left
registered and allocated) if the port was never opened in between.

Make sure to clear the port client data on any probe errors to avoid a
use-after-free when the client is later deregistered unconditionally
(e.g. in a tty-port deregistration helper).

Also move port client operation initialisation to registration. Note
that the client ops must be restored on failed probe.

Fixes: bed35c6dfa ("serdev: add a tty port controller driver")
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 16:41:49 +02:00
Stefan Wahren
56c607b509 tty: serdev-ttyport: return actual baudrate from ttyport_set_baudrate
Instead of returning the requested baudrate, we better return the
actual one because it isn't always the same.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 16:19:16 +02:00
Sebastian Reichel
5659dab26f serdev: implement get/set tiocm
Add method for getting and setting tiocm.

Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2017-04-12 22:12:17 +02:00
Sebastian Reichel
b3f80c8f75 serdev: add serdev_device_wait_until_sent
Add method, which waits until the transmission buffer has been sent.
Note, that the change in ttyport_write_wakeup is related, since
tty_wait_until_sent will hang without that change.

Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2017-04-12 22:12:16 +02:00
Dan Carpenter
10d258c518 serdev: ttyport: check whether tty_init_dev() fails
My static checker complains that we don't have any error handling here.
It's simple enough to add it.

Fixes: bed35c6dfa ("serdev: add a tty port controller driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-09 13:54:49 +01:00
Rob Herring
bed35c6dfa serdev: add a tty port controller driver
Add a serdev controller driver for tty ports.

The controller is registered with serdev when tty ports are registered
with the TTY core. As the TTY core is built-in only, this has the side
effect of making serdev built-in as well.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-By: Sebastian Reichel <sre@kernel.org>
Tested-By: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-03 10:17:02 +01:00