kernel/linux.git/drivers/tty/serdev/serdev-ttyport.c, branch v4.14.263

serdev: ttyport: restore client ops on deregistration

2020-02-28T15:36:12+00:00

commit 0c5aae59270fb1f827acce182786094c9ccf598e upstream. The serdev tty-port controller driver should reset the tty-port client operations also on deregistration to avoid a NULL-pointer dereference in case the port is later re-registered as a normal tty device. Note that this can only happen with tty drivers such as 8250 which have statically allocated port structures that can end up being reused and where a later registration would not register a serdev controller (e.g. due to registration errors or if the devicetree has been changed in between). Specifically, this can be an issue for any statically defined ports that would be registered by 8250 core when an 8250 driver is being unbound. Fixes: bed35c6dfa6a ("serdev: add a tty port controller driver") Cc: stable # 4.11 Reported-by: Loic Poulain Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20200210145730.22762-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

serdev: ttyport: enforce tty-driver open() requirement

2017-12-20T09:10:33+00:00

[ Upstream commit dee7d0f3b200c67c6ee96bd37c6e8fa52690ab56 ] 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 Acked-by: Rob Herring Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

serdev: ttyport: fix tty locking in close

2017-12-14T08:52:44+00:00

commit 90dbad8cd6efccbdce109d5ef0724f8434a6cdde 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: cd6484e1830b ("serdev: Introduce new bus for serial attached devices") Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman

serdev: ttyport: fix NULL-deref on hangup

2017-12-14T08:52:44+00:00

commit 8bcd4e6a8decac251d55c4377e2e67f052777ce0 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: bed35c6dfa6a ("serdev: add a tty port controller driver") Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman

serdev: ttyport: add missing receive_buf sanity checks

2017-12-14T08:52:44+00:00

commit eb281683621b71ab9710d9dccbbef0c2e1769c97 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: cd6484e1830b ("serdev: Introduce new bus for serial attached devices") Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman

Merge 4.12-rc3 into tty-next

2017-05-29T06:18:15+00:00

We need the tty fixes/changes here to handle future work. Signed-off-by: Greg Kroah-Hartman

tty/serdev: add serdev registration interface

2017-05-18T15:38:24+00:00

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 Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman

serdev: fix tty-port client deregistration

2017-05-18T14:41:49+00:00

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: bed35c6dfa6a ("serdev: add a tty port controller driver") Signed-off-by: Johan Hovold Reviewed-by: Rob Herring Cc: stable Signed-off-by: Greg Kroah-Hartman

tty: serdev-ttyport: return actual baudrate from ttyport_set_baudrate

2017-05-18T14:19:16+00:00

Instead of returning the requested baudrate, we better return the actual one because it isn't always the same. Signed-off-by: Stefan Wahren Acked-by: Rob Herring Signed-off-by: Greg Kroah-Hartman

serdev: implement get/set tiocm

2017-04-12T20:12:17+00:00

Add method for getting and setting tiocm. Acked-by: Pavel Machek Acked-by: Rob Herring Signed-off-by: Sebastian Reichel Acked-by: Greg Kroah-Hartman Signed-off-by: Marcel Holtmann