linux.git/drivers/tty/vt/vt.c, branch v6.8

vt: fix unicode buffer corruption when deleting characters

2024-03-02T22:09:04+00:00

This is the same issue that was fixed for the VGA text buffer in commit
39cdb68c64d8 ("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 
Fixes: 81732c3b2fed ("tty vt: Fix line garbage in virtual console on command line edition")
Cc: stable 
Link: https://lore.kernel.org/r/sn184on2-3p0q-0qrq-0218-895349s4753o@syhkavp.arg
Signed-off-by: Greg Kroah-Hartman

tty: vt: make vtconsole_class constant

2023-10-07T09:18:48+00:00

Now that the driver core allows for struct class to be in read-only
memory, making all 'class' structures to be declared at build time
placing them into read-only memory, instead of having to be dynamically
allocated at load time.

Cc: Jiri Slaby 
Link: https://lore.kernel.org/r/2023100546-humbly-prologue-e58c@gregkh
Signed-off-by: Greg Kroah-Hartman

tty: Restrict access to TIOCLINUX' copy-and-paste subcommands

2023-10-05T09:24:43+00:00

TIOCLINUX can be used for privilege escalation on virtual terminals when
code is executed via tools like su/sudo and sandboxing tools.

By abusing the selection features, a lower-privileged application can
write content to the console, select and copy/paste that content and
thereby executing code on the privileged account. See also the poc
here:

  https://www.openwall.com/lists/oss-security/2023/03/14/3

Selection is usually used by tools like gpm that provide mouse features
on the virtual console. gpm already runs as root (due to earlier
changes that restrict access to a user on the current TTY), therefore
it will still work with this change.

With this change, the following TIOCLINUX subcommands require
CAP_SYS_ADMIN:

 * TIOCL_SETSEL - setting the selected region on the terminal
 * TIOCL_PASTESEL - pasting the contents of the selected region into
   the input buffer
 * TIOCL_SELLOADLUT - changing word-by-word selection behaviour

The security problem mitigated is similar to the security risks caused
by TIOCSTI, which, since kernel 6.2, can be disabled with
CONFIG_LEGACY_TIOCSTI=n.

Signed-off-by: Hanno Böck 
Signed-off-by: Günther Noack 
Tested-by: Günther Noack 
Link: https://lore.kernel.org/r/20230828164117.3608812-2-gnoack@google.com
Signed-off-by: Greg Kroah-Hartman

tty: stop using ndash in kernel-doc

2023-10-03T12:31:16+00:00

An ndash used instead of a single dash renders a bullet to the result.
So use only single dashes in kernel-doc.

Signed-off-by: "Jiri Slaby (SUSE)" 
Link: https://lore.kernel.org/r/20230919085156.1578-11-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman

tty: make tty_operations::write()'s count size_t

2023-08-11T19:12:46+00:00

Unify with the rest of the code. Use size_t for counts and ssize_t for
retval.

Signed-off-by: "Jiri Slaby (SUSE)" 
Link: https://lore.kernel.org/r/20230810091510.13006-30-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman

tty: propagate u8 data to tty_operations::put_char()

2023-08-11T19:12:46+00:00

Data are now typed as u8. Propagate this change to
tty_operations::put_char().

Signed-off-by: "Jiri Slaby (SUSE)" 
Cc: Geert Uytterhoeven 
Cc: Heiko Carstens 
Cc: Vasily Gorbik 
Cc: Alexander Gordeev 
Cc: Christian Borntraeger 
Cc: Sven Schnelle 
Cc: Karsten Keil 
Cc: Greg Kroah-Hartman 
Cc: Jiri Slaby 
Cc: Shawn Guo 
Cc: Sascha Hauer 
Cc: Pengutronix Kernel Team 
Cc: Fabio Estevam 
Cc: NXP Linux Team 
Cc: Mathias Nyman 
Link: https://lore.kernel.org/r/20230810091510.13006-29-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman

tty: propagate u8 data to tty_operations::write()

2023-08-11T19:12:46+00:00

Data are now typed as u8. Propagate this change to
tty_operations::write().

Signed-off-by: "Jiri Slaby (SUSE)" 
Cc: Richard Henderson 
Cc: Ivan Kokshaysky 
Cc: Matt Turner 
Cc: Geert Uytterhoeven 
Cc: Richard Weinberger 
Cc: Anton Ivanov 
Cc: Johannes Berg 
Cc: Chris Zankel 
Cc: Max Filippov 
Cc: Arnd Bergmann 
Cc: Vaibhav Gupta 
Cc: Jens Taprogge 
Cc: Karsten Keil 
Cc: Scott Branden 
Cc: Ulf Hansson 
Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Jakub Kicinski 
Cc: Paolo Abeni 
Cc: Heiko Carstens 
Cc: Vasily Gorbik 
Cc: Alexander Gordeev 
Cc: Christian Borntraeger 
Cc: Sven Schnelle 
Cc: David Lin 
Cc: Johan Hovold 
Cc: Alex Elder 
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: Arnaud Pouliquen 
Cc: Oliver Neukum 
Cc: Mathias Nyman 
Cc: Marcel Holtmann 
Cc: Johan Hedberg 
Cc: Luiz Augusto von Dentz 
Link: https://lore.kernel.org/r/20230810091510.13006-28-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman

tty: vt: Remove some repetitive initialization

2023-08-03T07:51:51+00:00

Members vc_col, vc_rows and vc_size_row of the struct vc_data have been
initialized in visual_init(), so it is no longer needed to initialize
them in vc_init() again.

Signed-off-by: oushixiong 
Reviewed-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20230803065409.461031-1-oushixiong@kylinos.cn
Signed-off-by: Greg Kroah-Hartman

Merge tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2023-04-27T18:53:57+00:00

Pull driver core updates from Greg KH:
 "Here is the large set of driver core changes for 6.4-rc1.

  Once again, a busy development cycle, with lots of changes happening
  in the driver core in the quest to be able to move "struct bus" and
  "struct class" into read-only memory, a task now complete with these
  changes.

  This will make the future rust interactions with the driver core more
  "provably correct" as well as providing more obvious lifetime rules
  for all busses and classes in the kernel.

  The changes required for this did touch many individual classes and
  busses as many callbacks were changed to take const * parameters
  instead. All of these changes have been submitted to the various
  subsystem maintainers, giving them plenty of time to review, and most
  of them actually did so.

  Other than those changes, included in here are a small set of other
  things:

   - kobject logging improvements

   - cacheinfo improvements and updates

   - obligatory fw_devlink updates and fixes

   - documentation updates

   - device property cleanups and const * changes

   - firwmare loader dependency fixes.

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

* tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits)
  device property: make device_property functions take const device *
  driver core: update comments in device_rename()
  driver core: Don't require dynamic_debug for initcall_debug probe timing
  firmware_loader: rework crypto dependencies
  firmware_loader: Strip off \n from customized path
  zram: fix up permission for the hot_add sysfs file
  cacheinfo: Add use_arch[|_cache]_info field/function
  arch_topology: Remove early cacheinfo error message if -ENOENT
  cacheinfo: Check cache properties are present in DT
  cacheinfo: Check sib_leaf in cache_leaves_are_shared()
  cacheinfo: Allow early level detection when DT/ACPI info is missing/broken
  cacheinfo: Add arm64 early level initializer implementation
  cacheinfo: Add arch specific early level initializer
  tty: make tty_class a static const structure
  driver core: class: remove struct class_interface * from callbacks
  driver core: class: mark the struct class in struct class_interface constant
  driver core: class: make class_register() take a const *
  driver core: class: mark class_release() as taking a const *
  driver core: remove incorrect comment for device_create*
  MIPS: vpe-cmp: remove module owner pointer from struct class usage.
  ...

tty: vt: drop checks for undefined VT_SINGLE_DRIVER

2023-04-20T11:48:50+00:00

VT_SINGLE_DRIVER is defined nowhere. Remove its checks. These were added
long time ago and never used.

Signed-off-by: Jiri Slaby (SUSE) 
Link: https://lore.kernel.org/r/20230420093559.13200-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman