linux-stable.git/drivers/tty/mxser.c, branch linux-5.15.y

mxser: fix xmit_buf leak in activate when LSR == 0xff

2022-04-08T12:23:43+00:00

[ Upstream commit cd3a4907ee334b40d7aa880c7ab310b154fd5cd4 ]

When LSR is 0xff in ->activate() (rather unlike), we return an error.
Provided ->shutdown() is not called when ->activate() fails, nothing
actually frees the buffer in this case.

Fix this by properly freeing the buffer in a designated label. We jump
there also from the "!info->type" if now too.

Fixes: 6769140d3047 ("tty: mxser: use the tty_port_open method")
Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20220124071430.14907-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

mxser: keep only !tty test in ISR

2022-01-27T10:04:30+00:00

[ Upstream commit 274ab58dc2b460cc474ffc7ccfcede4b2be1a3f5 ]

The others are superfluous with tty refcounting in place now. And they
are racy in fact:
* tty_port_initialized() reports false for a small moment after
  interrupts are enabled.
* closing is 1 while the port is still alive.

The queues are flushed later during close anyway. So there is no need
for this special handling. Actually, the ISR should not flush the
queues. It should behave as every other driver, just queue the chars
into tty buffer and go on. But this will be changed later. There is
still a lot code depending on having tty in ISR (and not only tty_port).

Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20211118073125.12283-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

mxser: use semi-colons instead of commas

2021-08-26T12:48:40+00:00

This code works, but it's cleaner to use semi-colons at the end of
a statement instead of a comma.

Acked-by: Jiri Slaby 
Signed-off-by: Dan Carpenter 
Link: https://lore.kernel.org/r/20210825072435.GB13013@kili
Signed-off-by: Greg Kroah-Hartman

tty: drop put_tty_driver

2021-07-27T10:17:21+00:00

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: stop using alloc_tty_driver

2021-07-27T10:17:20+00:00

alloc_tty_driver was deprecated by tty_alloc_driver in commit
7f0bc6a68ed9 (TTY: pass flags to alloc_tty_driver) in 2012.

I never got into eliminating alloc_tty_driver until now. So we still
have two functions for allocating drivers which might be confusing. So
get rid of alloc_tty_driver uses to eliminate it for good in the next
patch.

Note we need to switch return value checking as tty_alloc_driver uses
ERR_PTR. And flags are now a parameter of tty_alloc_driver.

Cc: Richard Henderson (odd fixer:ALPHA PORT)
Cc: Ivan Kokshaysky 
Cc: Matt Turner 
Cc: Geert Uytterhoeven 
Cc: "James E.J. Bottomley" 
Cc: Helge Deller 
Cc: Jeff Dike 
Cc: Richard Weinberger 
Cc: Anton Ivanov 
Cc: Chris Zankel 
Cc: Max Filippov 
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: Laurentiu Tudor 
Cc: Jiri Kosina 
Cc: David Sterba 
Cc: Shawn Guo 
Cc: Sascha Hauer 
Cc: Oliver Neukum 
Cc: Felipe Balbi 
Cc: Johan Hovold 
Cc: Marcel Holtmann 
Cc: Johan Hedberg 
Cc: Luiz Augusto von Dentz 
Acked-by: Samuel Iglesias Gonsálvez 
Acked-by: Max Filippov 
Acked-by: David Sterba 
Acked-by: Christian Borntraeger 
Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20210723074317.32690-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman

mxser: introduce mxser_16550A_or_MUST helper

2021-06-18T11:10:03+00:00

This check is used in the code on many places. Either in positive or
negative form. So introduce a helper called mxser_16550A_or_MUST for
this purpose. And replace all the occurrences.

This simplifies many ifs in there.

Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20210618061516.662-67-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman

mxser: rename flags to old_speed in mxser_set_serial_info

2021-06-18T11:10:03+00:00

Local 'flags' are used to store speed in mxser_set_serial_info, not
actual flags (by doing & ASYNC_SPD_MASK). So rename 'flags' to
'old_speed' (after what it is).

Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20210618061516.662-66-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman

mxser: use port variable in mxser_set_serial_info

2021-06-18T11:10:03+00:00

mxser_set_serial_info already defined a local 'port' of type struct
tty_port. So use it in the code everywhere.

This eliminates some text from the code there.

Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20210618061516.662-65-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman

mxser: access info->MCR under info->slock

2021-06-18T11:10:03+00:00

info->MCR is protected by info->slock all over the code. Extend the lock
in mxser_tiocmget around the info->MCR fetch too.

It likely doesn't change anything, but it's always good to be consistent.

Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20210618061516.662-64-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman

mxser: fix typos around enhanced mode

2021-06-18T11:10:03+00:00

Fix spelling of "enhanced" in macros and comments around them.

While "enchance" comes from the original Moxa's driver, I don't think it
was meant to be that. From the context, they obviously mean "enhanced".

Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20210618061516.662-63-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman