linux-dev/drivers/staging/greybus/uart.c, branch linus/master

staging: greybus: uart: fix tty use after free

2021-09-14T07:18:18Z

User space can hold a tty open indefinitely and tty drivers must not release the underlying structures until the last user is gone. Switch to using the tty-port reference counter to manage the life time of the greybus tty state to avoid use after free after a disconnect. Fixes: a18e15175708 ("greybus: more uart work") Cc: stable@vger.kernel.org # 4.9 Reviewed-by: Alex Elder Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20210906124538.22358-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: drop put_tty_driver

2021-07-27T10:17:21Z

put_tty_driver() is an alias for tty_driver_kref_put(). There is no need for two exported identical functions, therefore switch all users of old put_tty_driver() to new tty_driver_kref_put() and remove the former for good. Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Geert Uytterhoeven Cc: Jeff Dike Cc: Richard Weinberger Cc: Anton Ivanov Cc: Chris Zankel Cc: Max Filippov Cc: Arnd Bergmann Cc: Greg Kroah-Hartman Cc: Samuel Iglesias Gonsalvez Cc: Jens Taprogge Cc: Karsten Keil Cc: Scott Branden Cc: Ulf Hansson Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: David Lin Cc: Johan Hovold Cc: Alex Elder Cc: Jiri Slaby Cc: Laurentiu Tudor Cc: Jiri Kosina Cc: David Sterba Cc: Shawn Guo Cc: Sascha Hauer Cc: Pengutronix Kernel Team Cc: Fabio Estevam Cc: NXP Linux Team Cc: Oliver Neukum Cc: Felipe Balbi Cc: Mathias Nyman Cc: Marcel Holtmann Cc: Johan Hedberg Cc: Luiz Augusto von Dentz Acked-by: Alex Elder Acked-by: Christian Borntraeger Acked-by: Max Filippov Acked-by: David Sterba Acked-by: Samuel Iglesias Gonsálvez Signed-off-by: Jiri Slaby Link: https://lore.kernel.org/r/20210723074317.32690-8-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman

tty: make use of tty_get_{char,frame}_size

2021-06-15T12:03:27Z

In the previous patch, we introduced tty_get_char_size() and tty_get_frame_size() for computing character and frame sizes, respectively. Here, we make use of them in various tty drivers where applicable. The stats look nice: 12 insertions, 169 deletions. Cc: Arnd Bergmann Cc: David Lin Cc: Johan Hovold Cc: Alex Elder Cc: Shawn Guo Cc: Sascha Hauer Cc: Andy Gross Cc: Bjorn Andersson Cc: Maxime Coquelin Cc: Alexandre Torgue Cc: Oliver Neukum Acked-by: Alex Elder Signed-off-by: Jiri Slaby Link: https://lore.kernel.org/r/20210610090247.2593-4-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman

tty: make tty_operations::chars_in_buffer return uint

2021-05-13T16:29:11Z

tty_operations::chars_in_buffer is another hook which is expected to return values >= 0. So make it explicit by the return type too -- use unsigned int. Signed-off-by: Jiri Slaby Acked-By: Anton Ivanov Acked-by: David Sterba Cc: Jeff Dike Cc: Richard Weinberger Cc: Arnd Bergmann Cc: Samuel Iglesias Gonsalvez Cc: Jens Taprogge Cc: Karsten Keil Cc: Ulf Hansson Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: David Lin Cc: Johan Hovold Cc: Alex Elder Cc: Jiri Kosina Cc: Shawn Guo Cc: Sascha Hauer Cc: Oliver Neukum Cc: Felipe Balbi Cc: Mathias Nyman Cc: Marcel Holtmann Cc: Johan Hedberg Cc: Luiz Augusto von Dentz Link: https://lore.kernel.org/r/20210505091928.22010-27-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman

tty: make tty_operations::write_room return uint

2021-05-13T15:03:20Z

Line disciplines expect a positive value or zero returned from tty->ops->write_room (invoked by tty_write_room). So make this assumption explicit by using unsigned int as a return value. Both of tty->ops->write_room and tty_write_room. Signed-off-by: Jiri Slaby Acked-by: Laurentiu Tudor Acked-by: Alex Elder Acked-by: Max Filippov # xtensa Acked-by: David Sterba Acked-By: Anton Ivanov Acked-by: Geert Uytterhoeven Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: "James E.J. Bottomley" Cc: Helge Deller Cc: Jeff Dike Cc: Richard Weinberger Cc: Chris Zankel Cc: Arnd Bergmann Cc: Samuel Iglesias Gonsalvez Cc: Jens Taprogge Cc: Karsten Keil Cc: Scott Branden Cc: Ulf Hansson Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: David Lin Cc: Johan Hovold Cc: Jiri Kosina Cc: Shawn Guo Cc: Sascha Hauer Cc: Oliver Neukum Cc: Felipe Balbi Cc: Mathias Nyman Cc: Marcel Holtmann Cc: Johan Hedberg Cc: Luiz Augusto von Dentz Link: https://lore.kernel.org/r/20210505091928.22010-23-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman

staging: greybus: uart: clean up TIOCGSERIAL

2021-04-07T15:22:07Z

TIOCSSERIAL is a horrid, underspecified, legacy interface which for most serial devices is only useful for setting the close_delay and closing_wait parameters. The xmit_fifo_size parameter could be used to set the hardware transmit fifo size of a legacy UART when it could not be detected, but the interface is limited to eight bits and should be left unset when not used. Similarly, baud_base could be used to set the UART base clock when it could not be detected but might as well be left unset when it is not known. The type parameter could be used to set the UART type, but is better left unspecified (type unknown) when it isn't used. Note that some applications have historically expected TIOCGSERIAL to be implemented, but judging from the Debian sources, the port type not being PORT_UNKNOWN is only used to check for the existence of legacy serial ports (ttySn). Notably USB serial drivers like ftdi_sio have been using PORT_UNKNOWN for twenty years without any problems. Drop the bogus values provided by the greybus implementation. Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20210407102334.32361-8-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

staging: greybus: uart: fix unprivileged TIOCCSERIAL

2021-04-07T15:22:07Z

TIOCSSERIAL is a horrid, underspecified, legacy interface which for most serial devices is only useful for setting the close_delay and closing_wait parameters. A non-privileged user has only ever been able to set the since long deprecated ASYNC_SPD flags and trying to change any other *supported* feature should result in -EPERM being returned. Setting the current values for any supported features should return success. Fix the greybus implementation which instead indicated that the TIOCSSERIAL ioctl was not even implemented when a non-privileged user set the current values. Fixes: e68453ed28c5 ("greybus: uart-gb: now builds, more framework added") Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20210407102334.32361-7-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

staging: greybus: uart: fix TIOCSSERIAL jiffies conversions

2021-04-07T15:22:07Z

The port close_delay and closing_wait parameters set by TIOCSSERIAL are specified in jiffies and not milliseconds. Add the missing conversions so that TIOCSSERIAL works as expected also when HZ is not 1000. Fixes: e68453ed28c5 ("greybus: uart-gb: now builds, more framework added") Cc: stable@vger.kernel.org # 4.9 Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20210407102334.32361-6-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

Merge 5.7-rc7 into staging-next

2020-05-25T07:11:19Z

We need the staging/iio fixes in here as well. Signed-off-by: Greg Kroah-Hartman

staging: greybus: uart: replace driver line-coding struct

2020-05-15T13:47:31Z

Drop the driver version of the line-coding request and use the protocol definition directly as was originally intended instead. This specifically avoids having the two versions of what is supposed to be the same struct ever getting out of sync. Note that this has in fact already happened once when the protocol definition had its implicit padding removed while the driver struct wasn't updated. The fact that we used the size of the then larger driver struct when memcpying its content to the stack didn't exactly make things better. A later addition of a flow-control field incidentally made the structures match again. Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20200514070548.4423-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman