A mirror of the official Linux kernel repository just in case
Go to file
Tetsuo Handa 988d076336 vt_ioctl: make VT_RESIZEX behave like VT_RESIZE
syzbot is reporting UAF/OOB read at bit_putcs()/soft_cursor() [1][2], for
vt_resizex() from ioctl(VT_RESIZEX) allows setting font height larger than
actual font height calculated by con_font_set() from ioctl(PIO_FONT).
Since fbcon_set_font() from con_font_set() allocates minimal amount of
memory based on actual font height calculated by con_font_set(),
use of vt_resizex() can cause UAF/OOB read for font data.

VT_RESIZEX was introduced in Linux 1.3.3, but it is unclear that what
comes to the "+ more" part, and I couldn't find a user of VT_RESIZEX.

  #define VT_RESIZE   0x5609 /* set kernel's idea of screensize */
  #define VT_RESIZEX  0x560A /* set kernel's idea of screensize + more */

So far we are not aware of syzbot reports caused by setting non-zero value
to v_vlin parameter. But given that it is possible that nobody is using
VT_RESIZEX, we can try removing support for v_clin and v_vlin parameters.

Therefore, this patch effectively makes VT_RESIZEX behave like VT_RESIZE,
with emitting a message if somebody is still using v_clin and/or v_vlin
parameters.

[1] https://syzkaller.appspot.com/bug?id=32577e96d88447ded2d3b76d71254fb855245837
[2] https://syzkaller.appspot.com/bug?id=6b8355d27b2b94fb5cedf4655e3a59162d9e48e3

Reported-by: syzbot <syzbot+b308f5fd049fbbc6e74f@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+16469b5e8e5a72e9131e@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/4933b81b-9b1a-355b-df0e-9b31e8280ab9@i-love.sakura.ne.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-27 14:17:43 +02:00
arch * A defconfig fix, from Daniel Díaz. 2020-09-20 15:06:43 -07:00
block - Fix a regression in bdev partition locking (Christoph) 2020-09-11 11:55:28 -07:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2020-08-30 15:53:44 -07:00
Documentation dt-bindings: serial: renesas, hscif: Document r8a774e1 bindings 2020-09-27 14:12:55 +02:00
drivers vt_ioctl: make VT_RESIZEX behave like VT_RESIZE 2020-09-27 14:17:43 +02:00
fs fs/fs-writeback.c: adjust dirtytime_interval_handler definition to match prototype 2020-09-19 13:13:39 -07:00
include Merge ba31128384dfd ("Merge tag 'libnvdimm-fixes-5.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm") into tty-next 2020-09-21 18:26:09 +02:00
init init: fix error check in clean_path() 2020-09-04 09:16:58 -07:00
ipc ipc: adjust proc_ipc_sem_dointvec definition to match prototype 2020-09-05 12:14:29 -07:00
kernel Fix the seccomp syscall rewriting so that trace and audit see the 2020-09-20 15:37:15 -07:00
lib kcsan: kconfig: move to menu 'Generic Kernel Debugging Instruments' 2020-09-19 13:13:39 -07:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm mm: fix wake_page_function() comment typos 2020-09-20 10:38:47 -07:00
net NFS client bugfixes for Linux 5.9 2020-09-09 11:14:20 -07:00
samples treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
scripts kconfig: qconf: revive help message in the info view 2020-09-20 12:58:54 +09:00
security device_cgroup RCU warning fix from Amol Grover <frextrite@gmail.com> 2020-09-15 16:26:57 -07:00
sound sound fixes for 5.9-rc6 2020-09-18 11:38:08 -07:00
tools Fix noreturn detection for ignored sibling functions, from Josh 2020-09-20 15:31:04 -07:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt KVM: fix memory leak in kvm_io_bus_unregister_dev() 2020-09-11 13:15:11 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2020-09-01 12:53:42 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: Add ZSTD-compressed files 2020-07-31 11:50:49 +02:00
.mailmap mailmap: add older email addresses for Kees Cook 2020-09-19 13:13:38 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS CREDITS: Replace HTTP links with HTTPS ones 2020-07-23 14:53:58 -06:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: Fix Max's and Shravan's emails 2020-09-16 11:51:02 -07:00
Makefile Linux 5.9-rc6 2020-09-20 16:33:55 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.