Commit Graph

629 Commits

Author SHA1 Message Date
Günther Noack ee6a44da3c tty: Require CAP_SYS_ADMIN for all usages of TIOCL_SELMOUSEREPORT
This requirement was overeagerly loosened in commit 2f83e38a09
("tty: Permit some TIOCL_SETSEL modes without CAP_SYS_ADMIN"), but as
it turns out,

  (1) the logic I implemented there was inconsistent (apologies!),

  (2) TIOCL_SELMOUSEREPORT might actually be a small security risk
      after all, and

  (3) TIOCL_SELMOUSEREPORT is only meant to be used by the mouse
      daemon (GPM or Consolation), which runs as CAP_SYS_ADMIN
      already.

In more detail:

1. The previous patch has inconsistent logic:

   In commit 2f83e38a09 ("tty: Permit some TIOCL_SETSEL modes
   without CAP_SYS_ADMIN"), we checked for sel_mode ==
   TIOCL_SELMOUSEREPORT, but overlooked that the lower four bits of
   this "mode" parameter were actually used as an additional way to
   pass an argument.  So the patch did actually still require
   CAP_SYS_ADMIN, if any of the mouse button bits are set, but did not
   require it if none of the mouse buttons bits are set.

   This logic is inconsistent and was not intentional.  We should have
   the same policies for using TIOCL_SELMOUSEREPORT independent of the
   value of the "hidden" mouse button argument.

   I sent a separate documentation patch to the man page list with
   more details on TIOCL_SELMOUSEREPORT:
   https://lore.kernel.org/all/20250223091342.35523-2-gnoack3000@gmail.com/

2. TIOCL_SELMOUSEREPORT is indeed a potential security risk which can
   let an attacker simulate "keyboard" input to command line
   applications on the same terminal, like TIOCSTI and some other
   TIOCLINUX "selection mode" IOCTLs.

   By enabling mouse reporting on a terminal and then injecting mouse
   reports through TIOCL_SELMOUSEREPORT, an attacker can simulate
   mouse movements on the same terminal, similar to the TIOCSTI
   keystroke injection attacks that were previously possible with
   TIOCSTI and other TIOCL_SETSEL selection modes.

   Many programs (including libreadline/bash) are then prone to
   misinterpret these mouse reports as normal keyboard input because
   they do not expect input in the X11 mouse protocol form.  The
   attacker does not have complete control over the escape sequence,
   but they can at least control the values of two consecutive bytes
   in the binary mouse reporting escape sequence.

   I went into more detail on that in the discussion at
   https://lore.kernel.org/all/20250221.0a947528d8f3@gnoack.org/

   It is not equally trivial to simulate arbitrary keystrokes as it
   was with TIOCSTI (commit 83efeeeb3d ("tty: Allow TIOCSTI to be
   disabled")), but the general mechanism is there, and together with
   the small number of existing legit use cases (see below), it would
   be better to revert back to requiring CAP_SYS_ADMIN for
   TIOCL_SELMOUSEREPORT, as it was already the case before
   commit 2f83e38a09 ("tty: Permit some TIOCL_SETSEL modes without
   CAP_SYS_ADMIN").

3. TIOCL_SELMOUSEREPORT is only used by the mouse daemons (GPM or
   Consolation), and they are the only legit use case:

   To quote console_codes(4):

     The mouse tracking facility is intended to return
     xterm(1)-compatible mouse status reports.  Because the console
     driver has no way to know the device or type of the mouse, these
     reports are returned in the console input stream only when the
     virtual terminal driver receives a mouse update ioctl.  These
     ioctls must be generated by a mouse-aware user-mode application
     such as the gpm(8) daemon.

   Jared Finder has also confirmed in
   https://lore.kernel.org/all/491f3df9de6593df8e70dbe77614b026@finder.org/
   that Emacs does not call TIOCL_SELMOUSEREPORT directly, and it
   would be difficult to find good reasons for doing that, given that
   it would interfere with the reports that GPM is sending.

   More information on the interaction between GPM, terminals and the
   kernel with additional pointers is also available in this patch:
   https://lore.kernel.org/all/a773e48920aa104a65073671effbdee665c105fc.1603963593.git.tammo.block@gmail.com/

   For background on who else uses TIOCL_SELMOUSEREPORT: Debian Code
   search finds one page of results, the only two known callers are
   the two mouse daemons GPM and Consolation.  (GPM does not show up
   in the search results because it uses literal numbers to refer to
   TIOCLINUX-related enums.  I looked through GPM by hand instead.
   TIOCL_SELMOUSEREPORT is also not used from libgpm.)
   https://codesearch.debian.net/search?q=TIOCL_SELMOUSEREPORT

Cc: Jared Finder <jared@finder.org>
Cc: Jann Horn <jannh@google.com>
Cc: Hanno Böck <hanno@hboeck.de>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Kees Cook <kees@kernel.org>
Cc: stable <stable@kernel.org>
Fixes: 2f83e38a09 ("tty: Permit some TIOCL_SETSEL modes without CAP_SYS_ADMIN")
Signed-off-by: Günther Noack <gnoack3000@gmail.com>
Link: https://lore.kernel.org/r/20250411070144.3959-2-gnoack3000@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-11 16:59:19 +02:00
Thomas Gleixner 8fa7292fee treewide: Switch/rename to timer_delete[_sync]()
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.

Conversion was done with coccinelle plus manual fixups where necessary.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-04-05 10:30:12 +02:00
Günther Noack 2f83e38a09 tty: Permit some TIOCL_SETSEL modes without CAP_SYS_ADMIN
With this, processes without CAP_SYS_ADMIN are able to use TIOCLINUX with
subcode TIOCL_SETSEL, in the selection modes TIOCL_SETPOINTER,
TIOCL_SELCLEAR and TIOCL_SELMOUSEREPORT.

TIOCL_SETSEL was previously changed to require CAP_SYS_ADMIN, as this IOCTL
let callers change the selection buffer and could be used to simulate
keypresses.  These three TIOCL_SETSEL selection modes, however, are safe to
use, as they do not modify the selection buffer.

This fixes a mouse support regression that affected Emacs (invisible mouse
cursor).

Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/ee3ec63269b43b34e1c90dd8c9743bf8@finder.org
Fixes: 8d1b43f6a6 ("tty: Restrict access to TIOCLINUX' copy-and-paste subcommands")
Signed-off-by: Günther Noack <gnoack@google.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Link: https://lore.kernel.org/r/20250110142122.1013222-1-gnoack@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-13 06:46:50 +01:00
Jeongjun Park f956052e00 vt: prevent kernel-infoleak in con_font_get()
font.data may not initialize all memory spaces depending on the implementation
of vc->vc_sw->con_font_get. This may cause info-leak, so to prevent this, it
is safest to modify it to initialize the allocated memory space to 0, and it
generally does not affect the overall performance of the system.

Cc: stable@vger.kernel.org
Reported-by: syzbot+955da2d57931604ee691@syzkaller.appspotmail.com
Fixes: 05e2600cb0 ("VT: Bump font size limitation to 64x128 pixels")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Link: https://lore.kernel.org/r/20241010174619.59662-1-aha310510@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-11 08:27:36 +02:00
Al Viro 5f60d5f6bb move asm/unaligned.h to linux/unaligned.h
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.

auto-generated by the following:

for i in `git grep -l -w asm/unaligned.h`; do
	sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
	sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
2024-10-02 17:23:23 -04:00
Masahiro Yamada 7258fdd7d7 tty: vt: conmakehash: remove non-portable code printing comment header
Commit 6e20753da6 ("tty: vt: conmakehash: cope with abs_srctree no
longer in env") included <linux/limits.h>, which invoked another
(wrong) patch that tried to address a build error on macOS.

According to the specification [1], the correct header to use PATH_MAX
is <limits.h>.

The minimal fix would be to replace <linux/limits.h> with <limits.h>.

However, the following commits seem questionable to me:

 - 3bd85c6c97 ("tty: vt: conmakehash: Don't mention the full path of the input in output")
 - 6e20753da6 ("tty: vt: conmakehash: cope with abs_srctree no longer in env")

These commits made too many efforts to cope with a comment header in
drivers/tty/vt/consolemap_deftbl.c:

  /*
   * Do not edit this file; it was automatically generated by
   *
   * conmakehash drivers/tty/vt/cp437.uni > [this file]
   *
   */

With this commit, the header part of the generate C file will be
simplified as follows:

  /*
   * Automatically generated file; Do not edit.
   */

BTW, another series of excessive efforts for a comment header can be
seen in the following:

 - 5ef6dc08cf ("lib/build_OID_registry: don't mention the full path of the script in output")
 - 2fe29fe945 ("lib/build_OID_registry: avoid non-destructive substitution for Perl < 5.13.2 compat")

[1]: https://pubs.opengroup.org/onlinepubs/009695399/basedefs/limits.h.html

Fixes: 6e20753da6 ("tty: vt: conmakehash: cope with abs_srctree no longer in env")
Cc: stable <stable@kernel.org>
Reported-by: Daniel Gomez <da.gomez@samsung.com>
Closes: https://lore.kernel.org/all/20240807-macos-build-support-v1-11-4cd1ded85694@samsung.com/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20240809160853.1269466-1-masahiroy@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-13 11:06:29 +02:00
Max Krummenacher 6e20753da6 tty: vt: conmakehash: cope with abs_srctree no longer in env
conmakehash uses getenv("abs_srctree") from the environment to strip
the absolute path from the generated sources.
However since commit e2bad142bb ("kbuild: unexport abs_srctree and
abs_objtree") this environment variable no longer gets set.
Instead use basename() to indicate the used file in a comment of the
generated source file.

Fixes: 3bd85c6c97 ("tty: vt: conmakehash: Don't mention the full path of the input in output")
Cc: stable <stable@kernel.org>
Signed-off-by: Max Krummenacher <max.krummenacher@toradex.com>
Link: https://lore.kernel.org/stable/20240725132056.9151-1-max.oss.09%40gmail.com
Link: https://lore.kernel.org/r/20240725132056.9151-1-max.oss.09@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-31 12:31:32 +02:00
Hans de Goede 80c4d3d489 vt: keyboard: Use led_set_brightness() in LED trigger activate() callback
A LED trigger's activate() callback gets called when the LED trigger
gets activated for a specific LED, so that the trigger code can ensure
the LED state matches the current state of the trigger condition.

led_trigger_event() is intended for trigger condition state changes and
iterates over _all_ LEDs which are controlled by this trigger changing
the brightness of each of them.

In the activate() case only the brightness of the LED which is being
activated needs to change and that LED is passed as an argument to
activate(), switch to led_set_brightness() to only change the brightness
of the LED being activated.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240511152030.4848-1-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-04 14:00:53 +02:00
Linus Torvalds f6b8e86b7a TTY/Serial changes for 6.10-rc1
Here is the big set of tty/serial driver changes for 6.10-rc1.  Included
 in here are:
   - Usual good set of api cleanups and evolution by Jiri Slaby to make
     the serial interfaces move out of the 1990's by using kfifos instead
     of hand-rolling their own logic.
   - 8250_exar driver updates
   - max3100 driver updates
   - sc16is7xx driver updates
   - exar driver updates
   - sh-sci driver updates
   - tty ldisc api addition to help refuse bindings
   - other smaller serial driver updates
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty / serial updates from Greg KH:
 "Here is the big set of tty/serial driver changes for 6.10-rc1.
  Included in here are:

   - Usual good set of api cleanups and evolution by Jiri Slaby to make
     the serial interfaces move out of the 1990's by using kfifos
     instead of hand-rolling their own logic.

   - 8250_exar driver updates

   - max3100 driver updates

   - sc16is7xx driver updates

   - exar driver updates

   - sh-sci driver updates

   - tty ldisc api addition to help refuse bindings

   - other smaller serial driver updates

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (113 commits)
  serial: Clear UPF_DEAD before calling tty_port_register_device_attr_serdev()
  serial: imx: Raise TX trigger level to 8
  serial: 8250_pnp: Simplify "line" related code
  serial: sh-sci: simplify locking when re-issuing RXDMA fails
  serial: sh-sci: let timeout timer only run when DMA is scheduled
  serial: sh-sci: describe locking requirements for invalidating RXDMA
  serial: sh-sci: protect invalidating RXDMA on shutdown
  tty: add the option to have a tty reject a new ldisc
  serial: core: Call device_set_awake_path() for console port
  dt-bindings: serial: brcm,bcm2835-aux-uart: convert to dtschema
  tty: serial: uartps: Add support for uartps controller reset
  arm64: zynqmp: Add resets property for UART nodes
  dt-bindings: serial: cdns,uart: Add optional reset property
  serial: 8250_pnp: Switch to DEFINE_SIMPLE_DEV_PM_OPS()
  serial: 8250_exar: Keep the includes sorted
  serial: 8250_exar: Make type of bit the same in exar_ee_*_bit()
  serial: 8250_exar: Use BIT() in exar_ee_read()
  serial: 8250_exar: Switch to use dev_err_probe()
  serial: 8250_exar: Return directly from switch-cases
  serial: 8250_exar: Decrease indentation level
  ...
2024-05-22 11:53:02 -07:00
Linus Torvalds a19264d086 printk changes for 6.10
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Merge tag 'printk-for-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

Pull printk updates from Petr Mladek:

 - Use no_printk() instead of "if (0) printk()" constructs to avoid
   generating printk index for messages disabled at compile time

 - Remove deprecated strncpy/strcpy from printk.c

 - Remove redundant CONFIG_BASE_FULL in favor of CONFIG_BASE_SMALL

* tag 'printk-for-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk: cleanup deprecated uses of strncpy/strcpy
  printk: Remove redundant CONFIG_BASE_FULL
  printk: Change type of CONFIG_BASE_SMALL to bool
  printk: Fix LOG_CPU_MAX_BUF_SHIFT when BASE_SMALL is enabled
  ceph: Use no_printk() helper
  dyndbg: Use *no_printk() helpers
  dev_printk: Add and use dev_no_printk()
  printk: Let no_printk() use _printk()
2024-05-15 12:34:46 -07:00
Yoann Congal b3e90f375b printk: Change type of CONFIG_BASE_SMALL to bool
CONFIG_BASE_SMALL is currently a type int but is only used as a boolean.

So, change its type to bool and adapt all usages:
CONFIG_BASE_SMALL == 0 becomes !IS_ENABLED(CONFIG_BASE_SMALL) and
CONFIG_BASE_SMALL != 0 becomes  IS_ENABLED(CONFIG_BASE_SMALL).

Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Yoann Congal <yoann.congal@smile.fr>
Link: https://lore.kernel.org/r/20240505080343.1471198-3-yoann.congal@smile.fr
Signed-off-by: Petr Mladek <pmladek@suse.com>
2024-05-06 17:39:09 +02:00
Linus Torvalds 6bd23e0c2b tty: add the option to have a tty reject a new ldisc
... and use it to limit the virtual terminals to just N_TTY.  They are
kind of special, and in particular, the "con_write()" routine violates
the "writes cannot sleep" rule that some ldiscs rely on.

This avoids the

   BUG: sleeping function called from invalid context at kernel/printk/printk.c:2659

when N_GSM has been attached to a virtual console, and gsmld_write()
calls con_write() while holding a spinlock, and con_write() then tries
to get the console lock.

Tested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Daniel Starke <daniel.starke@siemens.com>
Reported-by: syzbot <syzbot+dbac96d8e73b61aa559c@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=dbac96d8e73b61aa559c
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20240423163339.59780-1-torvalds@linux-foundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-05-04 18:45:11 +02:00
Uwe Kleine-König 3bd85c6c97 tty: vt: conmakehash: Don't mention the full path of the input in output
This change strips $abs_srctree of the input file containing the
character mapping table in the generated output. The motivation for this
change is Yocto emitting a build warning

        WARNING: linux-lxatac-6.7-r0 do_package_qa: QA Issue: File /usr/src/debug/linux-lxatac/6.7-r0/drivers/tty/vt/consolemap_deftbl.c in package linux-lxatac-src contains reference to TMPDIR

So this change brings us one step closer to make the build result
reproducible independent of the build path.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20240311113017.483101-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-09 15:50:12 +02:00
Linus Torvalds 3bcb0bf65c TTY/Serial driver update for 6.9-rc1
Here is the big set of TTY/Serial driver updates and cleanups for
 6.9-rc1.  Included in here are:
   - more tty cleanups from Jiri
   - loads of 8250 driver cleanups from Andy
   - max310x driver updates
   - samsung serial driver updates
   - uart_prepare_sysrq_char() updates for many drivers
   - platform driver remove callback void cleanups
   - stm32 driver updates
   - other small tty/serial driver updates
 
 All of these have been in linux-next for a long time with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty / serial driver updates from Greg KH:
 "Here is the big set of TTY/Serial driver updates and cleanups for
  6.9-rc1. Included in here are:

   - more tty cleanups from Jiri

   - loads of 8250 driver cleanups from Andy

   - max310x driver updates

   - samsung serial driver updates

   - uart_prepare_sysrq_char() updates for many drivers

   - platform driver remove callback void cleanups

   - stm32 driver updates

   - other small tty/serial driver updates

  All of these have been in linux-next for a long time with no reported
  issues"

* tag 'tty-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (199 commits)
  dt-bindings: serial: stm32: add power-domains property
  serial: 8250_dw: Replace ACPI device check by a quirk
  serial: Lock console when calling into driver before registration
  serial: 8250_uniphier: Switch to use uart_read_port_properties()
  serial: 8250_tegra: Switch to use uart_read_port_properties()
  serial: 8250_pxa: Switch to use uart_read_port_properties()
  serial: 8250_omap: Switch to use uart_read_port_properties()
  serial: 8250_of: Switch to use uart_read_port_properties()
  serial: 8250_lpc18xx: Switch to use uart_read_port_properties()
  serial: 8250_ingenic: Switch to use uart_read_port_properties()
  serial: 8250_dw: Switch to use uart_read_port_properties()
  serial: 8250_bcm7271: Switch to use uart_read_port_properties()
  serial: 8250_bcm2835aux: Switch to use uart_read_port_properties()
  serial: 8250_aspeed_vuart: Switch to use uart_read_port_properties()
  serial: port: Introduce a common helper to read properties
  serial: core: Add UPIO_UNKNOWN constant for unknown port type
  serial: core: Move struct uart_port::quirks closer to possible values
  serial: sh-sci: Call sci_serial_{in,out}() directly
  serial: core: only stop transmit when HW fifo is empty
  serial: pch: Use uart_prepare_sysrq_char().
  ...
2024-03-21 12:44:10 -07:00
Nicolas Pitre 1581dafaf0 vt: fix unicode buffer corruption when deleting characters
This is the same issue that was fixed for the VGA text buffer in commit
39cdb68c64 ("vt: fix memory overlapping when deleting chars in the
buffer"). The cure is also the same i.e. replace memcpy() with memmove()
due to the overlaping buffers.

Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Fixes: 81732c3b2f ("tty vt: Fix line garbage in virtual console on command line edition")
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/sn184on2-3p0q-0qrq-0218-895349s4753o@syhkavp.arg
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-02 23:09:04 +01:00
Roman Žilka 8524788abf tty/vt: Corrected doc of vc_sanitize_unicode(), vc_translate_unicode()
Corrected the doc of vc_sanitize_unicode() and vc_translate_unicode(),
tightly coupled functions which parse UTF-8 byte sequences.
1. Desc. of @rescan corresponded to the meaning of the return value -1.
   Corrected + added "Return:" section.
2. Replaced the ambiguous "character" with "code point" or "byte".

Signed-off-by: Roman Žilka <roman.zilka@gmail.com>
Link: https://lore.kernel.org/r/bee9faa8-0ea7-4411-bf77-3cb2e06385c7@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-17 17:44:46 +01:00
Jiri Slaby (SUSE) 6cc3028f79 tty: vt: decrypt magic constants in vc_is_control()
0x0d00ff81 and 0x0800f501 are bitmasks of ASCII characters. Spell them
explicitly using BIT() + ASCII constants. GENMASK() is used for the
9-bit range in CTRL_ACTION.

This also modifies the 'if' checking if the masks should be applied.
>From a "random" ' ' to the actual size of the bitmasks' type.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-23-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:39 +00:00
Jiri Slaby (SUSE) 3701400a39 tty: vt: use ASCII enum constants in vt_console_print()
There are still numbers used for ASCII characters in vt_console_print().
As we have an ASCII enum now, use the constant names from the enum
instead.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-22-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:39 +00:00
Jiri Slaby (SUSE) 137eb9ad22 tty: vt: use switch+case in the ESgetpars case
To be uniform in the 'c' handling, use switch-case (with ranges) even in
the ESgetpars case in do_con_trol().

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-21-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:39 +00:00
Jiri Slaby (SUSE) 3d5f5b9711 tty: vt: use switch+case in the ESnonstd case
To be uniform in the 'c' handling, use switch-case (with ranges) even in
the ESnonstd case in do_con_trol().

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-20-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:39 +00:00
Jiri Slaby (SUSE) 798d8b1cfe tty: vt: add new helper for reseting vc parameters
The code to reset the vc parameter parsing is repeated on two locations.
Create a helper vc_reset_params() and use it on both of them.

And instead of a 'for' loop to clear the array of parameters, use
simpler memset().

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-19-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:39 +00:00
Jiri Slaby (SUSE) bc9d077a8d tty: vt: handle CSI+[ inside preexisting switch-case
In do_con_trol()'s ESsquare case, there is already a switch (c). It is
preceded by an 'if (c == '[')'. Despite this 'if' handles a state
transition and not a modifier, move it as one of the switch cases. This
makes all the 'c' decision making more obvious there.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-18-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:39 +00:00
Jiri Slaby (SUSE) fd5b40251a tty: vt: simplify ansi_control_string()
Given all the ANSI control states are sequential in the vc_ctl_state
enum, we can define first/last constants and use them in
ansi_control_string(). It makes the test simple and allows for removal
of the 'if' (which was unnecessary at all -- the 'return' should have
returned the 'if' content directly anyway).

And remove the useless comment -- it's clear from the function
prototype.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-17-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:39 +00:00
Jiri Slaby (SUSE) 22795b3c47 tty: vt: name, reflow and document enum vc_ctl_state
The enum for states is currently compact and undocumented. Put each
definition on a separate line and document them all using kernel-doc.

Document the same on the use sites.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-16-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:39 +00:00
Jiri Slaby (SUSE) 7c1c9c1494 tty: vt: move CSI ECMA handling to a separate function
Similar to previous moves, move also "CSI ..." (i.e. vc_priv == EPecma)
handling to a separate function.

This is the last large move of code out of do_con_trol(). And despite it
is still 151 lines of code (down from 407!), it is now quite easy to
folllow the transitions of the state machine in there. ESnonstd and
ESpalette handling still can be moved away, but it won't improve that
much.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-15-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:38 +00:00
Jiri Slaby (SUSE) de0f61f342 tty: vt: move CSI DEC handling to a separate function
The handling of "CSI ? ..." (i.e. vc_priv == EPdec) can be easily moved
out of do_con_trol() into a separate function. This again increases
readability of do_con_trol().

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-14-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:38 +00:00
Jiri Slaby (SUSE) a9ffb22347 tty: vt: separate ESesc state handling into handle_esc()
Similar to the ASCII handling, the ESC handling can be easily moved away
from do_con_trol(). So create a new handle_esc() for that.

And add a comment with an example.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-13-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:38 +00:00
Jiri Slaby (SUSE) ce66f8e387 tty: vt: extract ascii handling to handle_ascii()
To make the do_con_trol() a bit more understandable, extract the ASCII
handling (the switch-case) to a separate function.

Other nested switch-cases will follow in the next patches.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-12-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:38 +00:00
Jiri Slaby (SUSE) a8ccce55a8 tty: vt: accept u8 in do_con_trol() and vc_setGx()
These functions expect u8 as the control character. Switch the type from
'int' appropriately. The caller passing the value (do_con_write()) is
fixed as well.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-11-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:38 +00:00
Jiri Slaby (SUSE) 9156792bcf tty: vt: put cases on separate lines
Some cases of the CSI switch are stuffed on one line. Put them all to a
separate line as is dictated by the coding style (and for better
readability).

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-10-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:38 +00:00
Jiri Slaby (SUSE) cc8539cab4 tty: vt: rename setterm_command() to csi_RSB()
It follows naming of other similar functions. RSB stands here for Right
Square Bracket as (obviously) ']' cannot be in the function name.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-9-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:38 +00:00
Jiri Slaby (SUSE) f9ac8d4e9f tty: vt: define an enum for CSI+] codes
Decrypt the constant values by proper enum names. This time in
setterm_command() (to be renamed to csi_RSB() in the next patches).

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-8-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:38 +00:00
Jiri Slaby (SUSE) 0afaeb78d1 tty: vt: move CSI+n handling along to other ECMA CSIs
CSIs without [<=>?] modifiers (ECMA) are handled in the switch-case
below this DEC switch+case handler. So move this ECMA CSI+n there too as
it fits there better.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-7-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:37 +00:00
Jiri Slaby (SUSE) 9abe9bf574 tty: vt: remove unneeded assignment of EPecma to vc_priv
vc_data::vc_priv is _always_ assigned before the ESgetpars case is
entered (in ESsquare). Therefore, there is no need to reset it when
leaving the ESgetpars case. Note the state is set to ESnormal few lines
above, so ESgetpars is entered only by the next CSI.

Therefore, this obfuscation can be removed.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-6-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:37 +00:00
Jiri Slaby (SUSE) 58d1af9319 tty: vt: split DEC CSI+h/l handling into csi_DEC_hl()
The DEC and ECMA handling of CSI+h/l is needlessly complicated. Split
these two, so that DEC is handled when the state is EPdec ('CSI ?' was
seen) and ECMA is handled in the EPecma state (no '?').

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-5-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:37 +00:00
Jiri Slaby (SUSE) 69b2c2693a tty: vt: rename set_mode() to csi_hl()
It's how the other CSI handling functions are named, so unify to that.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:37 +00:00
Jiri Slaby (SUSE) 608053e194 tty: vt: define enums for CSI+h/l codes
Decrypt the constant values by proper enum names. This time in
set_mode().

Define two of them as DEC ('CSI ?') is about to be split away in the
next patches.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-3-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:37 +00:00
Jiri Slaby (SUSE) fb8fa9093a tty: vt: make rgb_from_256() slighly more comprehensible
* make the parameter unsigned, as it is expected to be unsigned,
* make the computation easier to follow -- step-by-step, and
* don't use 85 / 2 which is only a reduced form of 255 / 6 (by a factor
  3). Unlike the former, the latter can be understood.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-2-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-06 14:37:37 +00:00
Lukas Bulwahn 5c49b6a4a4 vt: remove superfluous CONFIG_HW_CONSOLE
The config HW_CONSOLE is always identical to the config VT and is not
visible in the kernel's build menuconfig. So, CONFIG_HW_CONSOLE is
redundant.

Replace all references to CONFIG_HW_CONSOLE with CONFIG_VT and remove
CONFIG_HW_CONSOLE.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20240108134102.601-1-lukas.bulwahn@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 19:03:51 -08:00
Roman Žilka c01e71b49c tty/vt: UTF-8 parsing update according to RFC 3629, modern Unicode
vc_translate_unicode() and vc_sanitize_unicode() parse input to the
UTF-8-enabled console, marking invalid byte sequences and producing Unicode
codepoints. The current algorithm follows ancient Unicode and may accept
invalid byte sequences, pass on non-existent codepoints and reject valid
sequences.

The patch restores the functions' compliance with modern Unicode (v15.1 [1]
+ many previous versions) as well as RFC 3629 [2].
1. Codepoint space is limited to 0x10FFFF.
2. "Noncharacters", such as U+FFFE, U+FFFF, are no longer invalid in
   Unicode and will be accepted. Another option was to complete the set of
   noncharacters (used to be just those two, now there's more) and preserve
   the rejection step. This is indeed what Unicode suggests ([1] chap.
   23.7) (not requires), but most codepoints are !iswprint(), so selecting
   just the noncharacters seemed arbitrary and futile (and unnecessary).

This is not a security patch. I'm not aware of any present security
implications of the old code.

[1] https://www.unicode.org/versions/Unicode15.1.0
[2] https://datatracker.ietf.org/doc/html/rfc3629

Signed-off-by: Roman Žilka <roman.zilka@gmail.com>
Link: https://lore.kernel.org/r/598ab459-6ba9-4a17-b4a1-08f26a356fc0@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 19:01:27 -08:00
Jiri Slaby (SUSE) 60234365ae tty: vt: fix up kernel-doc
selection.c and vt.c still uses tabs in the kernel-doc. This misrenders the
functions in the output -- sphinx misinterprets the description. So
remove these tabs, incl. those around dashes.

'enum' keyword is needed before enum names. Fix that.

Superfluous \n after the comments are also removed. They are not
completely faulty, but this unifies all the kernel-doc in the files.

Finally fix up the cross references.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-47-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 18:08:55 -08:00
Jiri Slaby (SUSE) b23bf1a43b tty: vt: remove unused consw::con_flush_scrollback()
consw::con_flush_scrollback() is unused since commit 973c096f6a
(vgacon: remove software scrollback support). Drop it.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-45-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 18:08:55 -08:00
Jiri Slaby (SUSE) f441aa3b44 tty: vt: remove consw::con_getxy()
After the previous patch, nobody sets that hook. So drop it completely.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-44-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 18:08:55 -08:00
Jiri Slaby (SUSE) fd1ca81971 tty: vt: make types of screenpos() more consistent
* parameter offset: it is expected to be non-negative, so switch to
  unsigned
* return type: switch from ushort to explicit u16. This is expected on
  most places. And fix the remaining two places too.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-42-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 18:08:55 -08:00
Jiri Slaby (SUSE) 7cf01c92ad tty: vt: remove consw::con_screen_pos()
After the previous patch, nobody sets that hook. So drop it completely.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-41-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 18:08:55 -08:00
Jiri Slaby (SUSE) fd0f631fff tty: vt: make font of consw::con_font_set() const
Provided the font parameter of consw::con_font_set() is not supposed to
be changed, make it const.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-parisc@vger.kernel.org
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-37-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 18:08:54 -08:00
Jiri Slaby (SUSE) 0a58d83dfb tty: vt: use enum constants for VESA blanking modes
Use the new enum for VESA constants. This improves type checking in
consw::con_blank().

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-parisc@vger.kernel.org
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-35-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 18:08:54 -08:00
Jiri Slaby (SUSE) 15d0fff7d6 tty: vt: use VESA blanking constants
There are VESA blanking constants defined in vesa.h. So use them in the
console code instead of constant values.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-parisc@vger.kernel.org
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-34-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 18:08:54 -08:00
Jiri Slaby (SUSE) 735a51943f tty: vt: stop using -1 for blank mode in consw::con_blank()
-1 is the same as VESA_VSYNC_SUSPEND in all con_blank() implementations.
So we can remove this special case from vgacon now too.

Despite con_blank() of fbcon looks complicated, the "if
(!fbcon_is_inactive(vc, info))" branch is not taken as we set
"ops->graphics = 1;" few lines above. So what matters there (as in all
other blank implementations except vgacon) is if 'blank' is zero or not.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-32-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 18:08:54 -08:00
Jiri Slaby (SUSE) 8d5cc8eed7 tty: vt: make consw::con_switch() return a bool
The non-zero (true) return value from consw::con_switch() means a redraw
is needed. So make this return type a bool explicitly instead of int.
The latter might imply that -Eerrors are expected. They are not.

And document the hook.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-parisc@vger.kernel.org
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-31-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 18:08:54 -08:00