user/sven/linux.git/include/linux/tty.h, branch v5.12.1

Merge tag 'tty-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2021-02-21T05:28:04Z

Pull tty/serial driver updates from Greg KH: "Here is the big set of tty/serial driver changes for 5.12-rc1. Nothing huge, just lots of good cleanups and additions: - n_tty line discipline cleanups - vt core cleanups and reworks to make the code more "modern" - stm32 driver additions - tty led support added to the tty core and led layer - minor serial driver fixups and additions All of these have been in linux-next for a while with no reported issues" * tag 'tty-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (54 commits) serial: core: Remove BUG_ON(in_interrupt()) check vt_ioctl: Remove in_interrupt() check dt-bindings: serial: imx: Switch to my personal address vt: keyboard, use new API for keyboard_tasklet serial: stm32: improve platform_get_irq condition handling in init_port serial: ifx6x60: Remove driver for deprecated platform tty: fix up iterate_tty_read() EOVERFLOW handling tty: fix up hung_up_tty_read() conversion tty: fix up hung_up_tty_write() conversion tty: teach the n_tty ICANON case about the new "cookie continuations" too tty: teach n_tty line discipline about the new "cookie continuations" tty: clean up legacy leftovers from n_tty line discipline tty: implement read_iter tty: convert tty_ldisc_ops 'read()' function to take a kernel pointer serial: remove sirf prima/atlas driver serial: mxs-auart: Remove serial: mxs-auart: Remove serial_mxs_probe_dt() serial: fsl_lpuart: Use of_device_get_match_data() dt-bindings: serial: renesas,hscif: Add r8a779a0 support tty: serial: Drop unused efm32 serial driver ...

Commit 9bb48c82aced ("tty: implement write_iter") converted the tty

2021-01-25T20:08:07Z

layer to use write_iter. Fix the redirected_tty_write declaration also in n_tty and change the comparisons to use write_iter instead of write. [ Also moved the declaration of redirected_tty_write() to the proper location in a header file. The reason for the bug was the bogus extern declaration in n_tty.c silently not matching the changed definition in tty_io.c, and because it wasn't in a shared header file, there was no cross-checking of the declaration. Sami noticed because Clang's Control Flow Integrity checking ended up incidentally noticing the inconsistent declaration. - Linus ] Fixes: 9bb48c82aced ("tty: implement write_iter") Signed-off-by: Sami Tolvanen Signed-off-by: Linus Torvalds

tty: Export redirect release

2021-01-07T15:30:55Z

This will be required by the pty code when it removes tty_vhangup() on master close. Signed-off-by: Corey Minyard Link: https://lore.kernel.org/r/20201124004902.1398477-2-minyard@acm.org Signed-off-by: Greg Kroah-Hartman

tty_port: drop last traces of low_latency

2021-01-07T15:17:32Z

The main purpose of tty_port::low_latency was removed in commit a9c3f68f3cd8 (tty: Fix low_latency BUG) back in 2014. It was left in place for drivers as an optional tune knob. But only one driver has been using it until the previous commit. So remove this misconcept completely, given there are no users. Signed-off-by: Jiri Slaby Link: https://lore.kernel.org/r/20210105120239.28031-11-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman

tty: new helper function tty_get_icount()

2020-12-28T15:09:29Z

For a given struct tty_struct this yields the corresponding statistics about sent and received characters (and some more) which is needed to implement an LED trigger for tty devices. The new function is then used to simplify tty_tiocgicount(). Reviewed-by: Pavel Machek Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20201218104246.591315-3-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman

tty: rename tty_kopen() and add new function tty_kopen_shared()

2020-12-28T15:09:11Z

Introduce a new function tty_kopen_shared() that yields a struct tty_struct. The semantic difference to tty_kopen() is that the tty is expected to be used already. So rename tty_kopen() to tty_kopen_exclusive() for clearness, adapt the single user and put the common code in a new static helper function. tty_kopen_shared is to be used to implement an LED trigger for tty devices in one of the next patches. Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20201218104246.591315-2-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman

tty: use const parameters in port-flag accessors

2020-12-09T14:27:42Z

Declare the port parameter to the flag-test accessors as const. This is currently mostly cosmetic as the accessors are already inlined. Suggested-by: Jiri Slaby Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20201202113942.27024-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: use assign_bit() in port-flag accessors

2020-12-09T14:26:31Z

Use the new assign_bit() wrapper in the port-flag accessors instead of open coding. Suggested-by: Jiri Slaby Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20201202113942.27024-2-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

Merge 5.10-rc7 into tty-next

2020-12-07T09:19:31Z

We want the tty fixes in here as well. Signed-off-by: Greg Kroah-Hartman

tty: Fix ->session locking

2020-12-04T16:39:58Z

Currently, locking of ->session is very inconsistent; most places protect it using the legacy tty mutex, but disassociate_ctty(), __do_SAK(), tiocspgrp() and tiocgsid() don't. Two of the writers hold the ctrl_lock (because they already need it for ->pgrp), but __proc_set_tty() doesn't do that yet. On a PREEMPT=y system, an unprivileged user can theoretically abuse this broken locking to read 4 bytes of freed memory via TIOCGSID if tiocgsid() is preempted long enough at the right point. (Other things might also go wrong, especially if root-only ioctls are involved; I'm not sure about that.) Change the locking on ->session such that: - tty_lock() is held by all writers: By making disassociate_ctty() hold it. This should be fine because the same lock can already be taken through the call to tty_vhangup_session(). The tricky part is that we need to shorten the area covered by siglock to be able to take tty_lock() without ugly retry logic; as far as I can tell, this should be fine, since nothing in the signal_struct is touched in the `if (tty)` branch. - ctrl_lock is held by all writers: By changing __proc_set_tty() to hold the lock a little longer. - All readers that aren't holding tty_lock() hold ctrl_lock: By adding locking to tiocgsid() and __do_SAK(), and expanding the area covered by ctrl_lock in tiocspgrp(). Cc: stable@kernel.org Signed-off-by: Jann Horn Reviewed-by: Jiri Slaby Signed-off-by: Greg Kroah-Hartman