Thomas Zimmermann requested a fixes backmerge, specifically also for
96c5f82ef0 ("drm/vc4: fix error code in vc4_create_object()")
Just a bunch of adjacent changes conflicts, even the big pile of them
in vc4.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The "nomodeset" kernel cmdline parameter is handled by the vgacon driver
but the exported vgacon_text_force() symbol is only used by DRM drivers.
It makes much more sense for the parameter logic to be in the subsystem
of the drivers that are making use of it.
Let's move the vgacon_text_force() function and related logic to the DRM
subsystem. While doing that, rename it to drm_firmware_drivers_only() and
make it return true if "nomodeset" was used and false otherwise. This is
a better description of the condition that the drivers are testing for.
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211112133230.1595307-4-javierm@redhat.com
Fix a division by zero in `vgacon_resize' with a backtrace like:
vgacon_resize
vc_do_resize
vgacon_init
do_bind_con_driver
do_unbind_con_driver
fbcon_fb_unbind
do_unregister_framebuffer
do_register_framebuffer
register_framebuffer
__drm_fb_helper_initial_config_and_unlock
drm_helper_hpd_irq_event
dw_hdmi_irq
irq_thread
kthread
caused by `c->vc_cell_height' not having been initialized. This has
only started to trigger with commit 860dafa902 ("vt: Fix character
height handling with VT_RESIZEX"), however the ultimate offender is
commit 50ec42edd9 ("[PATCH] Detaching fbcon: fix vgacon to allow
retaking of the console").
Said commit has added a call to `vc_resize' whenever `vgacon_init' is
called with the `init' argument set to 0, which did not happen before.
And the call is made before a key vgacon boot parameter retrieved in
`vgacon_startup' has been propagated in `vgacon_init' for `vc_resize' to
use to the console structure being worked on. Previously the parameter
was `c->vc_font.height' and now it is `c->vc_cell_height'.
In this particular scenario the registration of fbcon has failed and vt
resorts to vgacon. Now fbcon does have initialized `c->vc_font.height'
somehow, unlike `c->vc_cell_height', which is why this code did not
crash before, but either way the boot parameters should have been copied
to the console structure ahead of the call to `vc_resize' rather than
afterwards, so that first the call has a chance to use them and second
they do not change the console structure to something possibly different
from what was used by `vc_resize'.
Move the propagation of the vgacon boot parameters ahead of the call to
`vc_resize' then. Adjust the comment accordingly.
Fixes: 50ec42edd9 ("[PATCH] Detaching fbcon: fix vgacon to allow retaking of the console")
Cc: stable@vger.kernel.org # v2.6.18+
Reported-by: Wim Osterholt <wim@djo.tudelft.nl>
Reported-by: Pavel V. Panteleev <panteleev_p@mcst.ru>
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2110252317110.58149@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sticon_build_attr() checked the reverse argument and flipped
background and foreground color, but returned the non-reverse
value afterwards. Fix this and also add two local variables
for foreground and background color to make the code easier
to read.
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Adjust the kconfig a little to allow disabling NO_IOMEM in UML. To
make an "allyesconfig" with CONFIG_NO_IOMEM=n build, adjust a few
Kconfig things elsewhere and add dummy asm/fb.h and asm/vga.h files.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Merge VT_RESIZEX fixes from Maciej Rozycki:
"I got to the bottom of the issue with VT_RESIZEX recently discussed
and came up with this small patch series, fixing an additional issue
that I originally thought might be broken VGA hardware emulation with
my laptop, which however turned out to be intertwined with the
original problem and also a regression introduced somewhat later.
The fix for that because the first patch, and then to make backporting
feasible I had to put a revert of the offending change from last
September next, followed by a proper fix for the framebuffer issue
that change had tried to address.
See individual change descriptions for details.
These have been verified with true VGA hardware (a Trident TVGA8900
ISA video adapter) using various combinations of `svgatextmode' and
`setfont' command invocations to change both the VT size and the font
size, and also switching between the text console and X11, both by
starting/stopping the X server and by switching between VTs.
All this to ensure bringing the behaviour of VGA text console back to
correct operation as it used to be with Linux 2.6.18"
* emailed patches from Maciej W. Rozycki <macro@orcam.me.uk>:
vt: Fix character height handling with VT_RESIZEX
vt_ioctl: Revert VT_RESIZEX parameter handling removal
vgacon: Record video mode changes with VT_RESIZEX
Restore the original intent of the VT_RESIZEX ioctl's `v_clin' parameter
which is the number of pixel rows per character (cell) rather than the
height of the font used.
For framebuffer devices the two values are always the same, because the
former is inferred from the latter one. For VGA used as a true text
mode device these two parameters are independent from each other: the
number of pixel rows per character is set in the CRT controller, while
font height is in fact hardwired to 32 pixel rows and fonts of heights
below that value are handled by padding their data with blanks when
loaded to hardware for use by the character generator. One can change
the setting in the CRT controller and it will update the screen contents
accordingly regardless of the font loaded.
The `v_clin' parameter is used by the `vgacon' driver to set the height
of the character cell and then the cursor position within. Make the
parameter explicit then, by defining a new `vc_cell_height' struct
member of `vc_data', set it instead of `vc_font.height' from `v_clin' in
the VT_RESIZEX ioctl, and then use it throughout the `vgacon' driver
except where actual font data is accessed which as noted above is
independent from the CRTC setting.
This way the framebuffer console driver is free to ignore the `v_clin'
parameter as irrelevant, as it always should have, avoiding any issues
attempts to give the parameter a meaning there could have caused, such
as one that has led to commit 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."
The problem first appeared around Linux 2.5.66 which predates our repo
history, but the origin could be identified with the old MIPS/Linux repo
also at: <git://git.kernel.org/pub/scm/linux/kernel/git/ralf/linux.git>
as commit 9736a3546de7 ("Merge with Linux 2.5.66."), where VT_RESIZEX
code in `vt_ioctl' was updated as follows:
if (clin)
- video_font_height = clin;
+ vc->vc_font.height = clin;
making the parameter apply to framebuffer devices as well, perhaps due
to the use of "font" in the name of the original `video_font_height'
variable. Use "cell" in the new struct member then to avoid ambiguity.
References:
[1] https://syzkaller.appspot.com/bug?id=32577e96d88447ded2d3b76d71254fb855245837
[2] https://syzkaller.appspot.com/bug?id=6b8355d27b2b94fb5cedf4655e3a59162d9e48e3
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org # v2.6.12+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix an issue with VGA console font size changes made after the initial
video text mode has been changed with a user tool like `svgatextmode'
calling the VT_RESIZEX ioctl. As it stands in that case the original
screen geometry continues being used to validate further VT resizing.
Consequently when the video adapter is firstly reprogrammed from the
original say 80x25 text mode using a 9x16 character cell (720x400 pixel
resolution) to say 80x37 text mode and the same character cell (720x592
pixel resolution), and secondly the CRTC character cell updated to 9x8
(by loading a suitable font with the KD_FONT_OP_SET request of the
KDFONTOP ioctl), the VT geometry does not get further updated from 80x37
and only upper half of the screen is used for the VT, with the lower
half showing rubbish corresponding to whatever happens to be there in
the video memory that maps to that part of the screen. Of course the
proportions change according to text mode geometries and font sizes
chosen.
Address the problem then, by updating the text mode geometry defaults
rather than checking against them whenever the VT is resized via a user
ioctl.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Fixes: e400b6ec4e ("vt/vgacon: Check if screen resize request comes from userspace")
Cc: stable@vger.kernel.org # v2.6.24+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
.con_font_set and .con_font_default callbacks should not pass `struct
console_font *` as a parameter, since `struct console_font` is a UAPI
structure.
We are trying to let them use our new kernel font descriptor, `struct
font_desc` instead. To make that work slightly easier, first delete all of
their no-op implementations used by dummy consoles.
This will make KD_FONT_OP_SET and KD_FONT_OP_SET_DEFAULT ioctl() requests
on dummy consoles start to fail and return `-ENOSYS`, which is intended,
since no user should ever expect such operations to succeed on dummy
consoles.
Suggested-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/9952c7538d2a32bb1a82af323be482e7afb3dedf.1605169912.git.yepeilin.cs@gmail.com
This is a major rework of the sticon (parisc text console) driver in
order to support user font support.
Usually one want to use the stifb (parisc framebuffer driver) which is
based on fbcon and does support fonts and colors, but some old machines
(e.g. HP 730 workstations) don't provide a supported stifb graphic card,
and for those user fonts are preferred.
This patch drops unused code for software cursor and scrollback,
enhances the debug output and adds better documentation.
The code was tested on various machines with byte-mode and word-mode
graphic cards on GSC- and PCI-busses.
Signed-off-by: Helge Deller <deller@gmx.de>
If the ROM provides functional STI routines, always register the sticon
driver, even if the serial console was choosen as boot device.
Additionally, in that case, do not make the sticon driver the default
output console device.
Signed-off-by: Helge Deller <deller@gmx.de>
Pull tty/serial updates from Greg KH:
"Here is the big set of tty and serial driver patches for 5.10-rc1.
Lots of little things in here, including:
- tasklet_setup api conversions
- sysrq support for capital letters
- vt and vc cleanups and unwinding the mess some more
- serial driver updates and minor tweaks
- new device ids
- rs485 support for some drivers
- serial binding documentation updates
- lots of small serial driver changes for reported issues
All have been in linux-next for a while with no reported issues"
* tag 'tty-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (79 commits)
serial: mcf: add sysrq capability
serial: fsl_lpuart: add sysrq support when using dma
fbcon: remove no-op fbcon_set_origin()
tty/sysrq: Extend the sysrq_key_table to cover capital letters
serial: max310x: rework RX interrupt handling
serial: 8250_dw: Fix clk-notifier/port suspend deadlock
serial: 8250: Skip uninitialized TTY port baud rate update
serial: 8250: Discard RTS/DTS setting from clock update method
tty: serial: imx: disable TXDC IRQ in imx_uart_shutdown() to avoid IRQ storm
serial: 8250_fsl: Fix TX interrupt handling condition
serial: pl011: Fix lockdep splat when handling magic-sysrq interrupt
tty: serial: fsl_lpuart: fix lpuart32_poll_get_char
tty: serial: lpuart: fix lpuart32_write usage
serial: qcom_geni_serial: To correct QUP Version detection logic
serial: mvebu-uart: fix unused variable warning
vt_ioctl: make VT_RESIZEX behave like VT_RESIZE
serial: mvebu-uart: simplify the return expression of mvebu_uart_probe()
tty: serial: imx: fix link error with CONFIG_SERIAL_CORE_CONSOLE=n
tty: hvc: fix link error with CONFIG_SERIAL_CORE_CONSOLE=n
pch_uart: drop double zeroing
...
We need the tty/serial fixes in here and this resolves a merge issue in
the 8250 driver.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Yunhai Zhang recently fixed a VGA software scrollback bug in commit
ebfdfeeae8 ("vgacon: Fix for missing check in scrollback handling"),
but that then made people look more closely at some of this code, and
there were more problems on the vgacon side, but also the fbcon software
scrollback.
We don't really have anybody who maintains this code - probably because
nobody actually _uses_ it any more. Sure, people still use both VGA and
the framebuffer consoles, but they are no longer the main user
interfaces to the kernel, and haven't been for decades, so these kinds
of extra features end up bitrotting and not really being used.
So rather than try to maintain a likely unused set of code, I'll just
aggressively remove it, and see if anybody even notices. Maybe there
are people who haven't jumped on the whole GUI badnwagon yet, and think
it's just a fad. And maybe those people use the scrollback code.
If that turns out to be the case, we can resurrect this again, once
we've found the sucker^Wmaintainer for it who actually uses it.
Reported-by: NopNop Nop <nopitydays@gmail.com>
Tested-by: Willy Tarreau <w@1wt.eu>
Cc: 张云海 <zhangyunhai@nsfocus.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull tty/serial updates from Greg KH:
"Here is the large set of TTY and Serial driver patches for 5.9-rc1.
Lots of bugfixes in here, thanks to syzbot fuzzing for serial and vt
and console code.
Other highlights include:
- much needed vt/vc code cleanup from Jiri Slaby
- 8250 driver fixes and additions
- various serial driver updates and feature enhancements
- locking cleanup for serial/console initializations
- other minor cleanups
All of these have been in linux-next with no reported issues"
* tag 'tty-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (90 commits)
MAINTAINERS: enlist Greg formally for console stuff
vgacon: Fix for missing check in scrollback handling
Revert "serial: 8250: Let serial core initialise spin lock"
serial: 8250: Let serial core initialise spin lock
tty: keyboard, do not speculate on func_table index
serial: stm32: Add RS485 RTS GPIO control
serial: 8250_dw: Fix common clocks usage race condition
serial: 8250_dw: Pass the same rate to the clk round and set rate methods
serial: 8250_dw: Simplify the ref clock rate setting procedure
serial: 8250: Add 8250 port clock update method
tty: serial: imx: add imx earlycon driver
tty: serial: imx: enable imx serial console port as module
tty/synclink: remove leftover bits of non-PCI card support
tty: Use the preferred form for passing the size of a structure type
tty: Fix identation issues in struct serial_struct32
tty: Avoid the use of one-element arrays
serial: msm_serial: add sparse context annotation
serial: pmac_zilog: add sparse context annotation
newport_con: vc_color is now in state
serial: imx: use hrtimers for rs485 delays
...
vgacon_scrollback_update() always leaves enbough room in the scrollback
buffer for the next call, but if the console size changed that room
might not actually be enough, and so we need to re-check.
The check should be in the loop since vgacon_scrollback_cur->tail is
updated in the loop and count may be more than 1 when triggered by CSI M,
as Jiri's PoC:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <fcntl.h>
int main(int argc, char** argv)
{
int fd = open("/dev/tty1", O_RDWR);
unsigned short size[3] = {25, 200, 0};
ioctl(fd, 0x5609, size); // VT_RESIZE
write(fd, "\e[1;1H", 6);
for (int i = 0; i < 30; i++)
write(fd, "\e[10M", 5);
}
It leads to various crashes as vgacon_scrollback_update writes out of
the buffer:
BUG: unable to handle page fault for address: ffffc900001752a0
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
RIP: 0010:mutex_unlock+0x13/0x30
...
Call Trace:
n_tty_write+0x1a0/0x4d0
tty_write+0x1a0/0x2e0
Or to KASAN reports:
BUG: KASAN: slab-out-of-bounds in vgacon_scroll+0x57a/0x8ed
This fixes CVE-2020-14331.
Reported-by: 张云海 <zhangyunhai@nsfocus.com>
Reported-by: Yang Yingliang <yangyingliang@huawei.com>
Reported-by: Kyungtae Kim <kt0755@gmail.com>
Fixes: 15bdab959c ([PATCH] vgacon: Add support for soft scrollback)
Cc: stable@vger.kernel.org
Cc: linux-fbdev@vger.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Solar Designer <solar@openwall.com>
Cc: "Srivatsa S. Bhat" <srivatsa@csail.mit.edu>
Cc: Anthony Liguori <aliguori@amazon.com>
Cc: Yang Yingliang <yangyingliang@huawei.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Yunhai Zhang <zhangyunhai@nsfocus.com>
Link: https://lore.kernel.org/r/9fb43895-ca91-9b07-ebfd-808cf854ca95@nsfocus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce names (en enum) for 0, 1, and 2 constants. We now have
VCI_HALF_BRIGHT, VCI_NORMAL, and VCI_BOLD instead.
Apart from the cleanup,
1) the enum allows for better type checking, and
2) this saves some code. No more fiddling with bits is needed in
assembly now. (OTOH, the structure is larger.)
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are two copies of some members of struct vc_data. This is because
we need to save them and restore later. Move these memebers to a
separate structure called vc_state. So now instead of members like:
vc_x, vc_y and vc_saved_x, vc_saved_y
we have
state and saved_state (of type: struct vc_state)
containing
state.x, state.y and saved_state.x, saved_state.y
This change:
* makes clear what is saved & restored
* eases save & restore by using memcpy (see save_cur and restore_cur)
Finally, we document the newly added struct vc_state using kernel-doc.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm-misc-next for v5.9:
UAPI Changes:
- Add DRM_MODE_TYPE_USERDEF for video modes specified in cmdline.
Cross-subsystem Changes:
- Assorted devicetree binding updates.
- Add might_sleep() to dma_fence_wait().
- Fix fbdev's get_user_pages_fast() handling, and use pin_user_pages.
- Small cleanup with IS_BUILTIN in video/fbdev drivers.
- Fix video/hdmi coding style for infoframe size.
Core Changes:
- Silence vblank output during init.
- Fix DP-MST corruption during send msg timeout.
- Clear leak in drm_gem_objecs_lookup().
- Make newlines work with force connector attribute.
- Fix module refcounting error in drm_encoder_slave, and use new i2c api.
- Header fix for drm_managed.c
- More struct_mutex removal for !legacy drivers:
- Remove gem_free_object()
- Removal of drm_gem_object_put_unlocked().
- Show current->comm alongside pid in debug printfs.
- Add drm_client_modeset_check() + drm_client_framebuffer_flush().
- Replace drm_fb_swab16 with drm_fb_swap that also supports 32-bits.
- Remove mode->vrefresh, and compactify drm_display_mode.
- Use drm_* macros for logging and warnings.
- Add WARN when drm_gem_get_pages is used on a private obj.
- Handle importing and imported dmabuf better in shmem helpers.
- Small fix for drm/mm hole size comparison, and remove invalid entry optimization.
- Add a drm/mm selftest.
- Set DSI connector type for DSI panels.
- Assorted small fixes and documentation updates.
- Fix DDI I2C device registration for MST ports, and flushing on destroy.
- Fix master_set return type, used by vmwgfx.
- Make the drm_set/drop_master ioctl symmetrical.
Driver Changes:
Allow iommu in the sun4i driver and use it for sun8i.
- Simplify backlight lookup for omap, amba-clcd and tilcdc.
- Hold reg_lock for rockchip.
- Add support for bridge gpio and lane reordering + polarity to ti-sn65dsi86, and fix clock choice.
- Small assorted fixes to tilcdc, vc4, i915, omap, fbdev/sm712fb, fbdev/pxafb, console/newport_con, msm, virtio, udl, malidp, hdlcd, bridge/ti-sn65dsi86, panfrost.
- Remove hw cursor support for mgag200, and use simple kms helper + shmem helpers.
- Add support for KOE Allow iommu in the sun4i driver and use it for sun8i.
- Simplify backlight lookup for omap, amba-clcd and tilcdc.
- Hold reg_lock for rockchip.
- Add support for bridge gpio and lane reordering + polarity to ti-sn65dsi86, and fix clock choice.
- Small assorted fixes to tilcdc, vc4 (multiple), i915.
- Remove hw cursor support for mgag200, and use simple kms helper + shmem helpers.
- Add support for KOE TX26D202VM0BWA panel.
- Use GEM CMA functions in arc, arm, atmel-hlcdc, fsi-dcu, hisilicon, imx, ingenic, komeda, malidp, mcde, meson, msxfb, rcar-du, shmobile, stm, sti, tilcdc, tve200, zte.
- Remove gem_print_info.
- Improve gem_create_object_helper so udl can use shmem helpers.
- Convert vc4 dt bindings to schemas, and add clock properties.
- Device initialization cleanups for mgag200.
- Add a workaround to fix DP-MST short pulses handling on broken hardware in i915.
- Allow build test compiling arm drivers.
- Use managed pci functions in mgag200 and ast.
- Use dev_groups in malidp.
- Add per pixel alpha support for PX30 VOP in rockchip.
- Silence deferred probe logs in panfrost.
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/001cd9a6-405d-4e29-43d8-354f53ae4e8b@linux.intel.com
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.
This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.
There are a variety of indentation styles found.
a) 4 spaces + '---help---'
b) 7 spaces + '---help---'
c) 8 spaces + '---help---'
d) 1 space + 1 tab + '---help---'
e) 1 tab + '---help---' (correct indentation)
f) 1 tab + 1 space + '---help---'
g) 1 tab + 2 spaces + '---help---'
In order to convert all of them to 1 tab + 'help', I ran the
following commend:
$ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
When syzkaller tests, there is a UAF:
BUG: KASan: use after free in vgacon_invert_region+0x9d/0x110 at addr
ffff880000100000
Read of size 2 by task syz-executor.1/16489
page:ffffea0000004000 count:0 mapcount:-127 mapping: (null)
index:0x0
page flags: 0xfffff00000000()
page dumped because: kasan: bad access detected
CPU: 1 PID: 16489 Comm: syz-executor.1 Not tainted
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
Call Trace:
[<ffffffffb119f309>] dump_stack+0x1e/0x20
[<ffffffffb04af957>] kasan_report+0x577/0x950
[<ffffffffb04ae652>] __asan_load2+0x62/0x80
[<ffffffffb090f26d>] vgacon_invert_region+0x9d/0x110
[<ffffffffb0a39d95>] invert_screen+0xe5/0x470
[<ffffffffb0a21dcb>] set_selection+0x44b/0x12f0
[<ffffffffb0a3bfae>] tioclinux+0xee/0x490
[<ffffffffb0a1d114>] vt_ioctl+0xff4/0x2670
[<ffffffffb0a0089a>] tty_ioctl+0x46a/0x1a10
[<ffffffffb052db3d>] do_vfs_ioctl+0x5bd/0xc40
[<ffffffffb052e2f2>] SyS_ioctl+0x132/0x170
[<ffffffffb11c9b1b>] system_call_fastpath+0x22/0x27
Memory state around the buggy address:
ffff8800000fff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00
ffff8800000fff80: 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00
>ffff880000100000: ff ff ff ff ff ff ff ff ff ff ff ff ff
ff ff ff
It can be reproduce in the linux mainline by the program:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <linux/vt.h>
struct tiocl_selection {
unsigned short xs; /* X start */
unsigned short ys; /* Y start */
unsigned short xe; /* X end */
unsigned short ye; /* Y end */
unsigned short sel_mode; /* selection mode */
};
#define TIOCL_SETSEL 2
struct tiocl {
unsigned char type;
unsigned char pad;
struct tiocl_selection sel;
};
int main()
{
int fd = 0;
const char *dev = "/dev/char/4:1";
struct vt_consize v = {0};
struct tiocl tioc = {0};
fd = open(dev, O_RDWR, 0);
v.v_rows = 3346;
ioctl(fd, VT_RESIZEX, &v);
tioc.type = TIOCL_SETSEL;
ioctl(fd, TIOCLINUX, &tioc);
return 0;
}
When resize the screen, update the 'vc->vc_size_row' to the new_row_size,
but when 'set_origin' in 'vgacon_set_origin', vgacon use 'vga_vram_base'
for 'vc_origin' and 'vc_visible_origin', not 'vc_screenbuf'. It maybe
smaller than 'vc_screenbuf'. When TIOCLINUX, use the new_row_size to calc
the offset, it maybe larger than the vga_vram_size in vgacon driver, then
bad access.
Also, if set an larger screenbuf firstly, then set an more larger
screenbuf, when copy old_origin to new_origin, a bad access may happen.
So, If the screen size larger than vga_vram, resize screen should be
failed. This alse fix CVE-2020-8649 and CVE-2020-8647.
Linus pointed out that overflow checking seems absent. We're saved by
the existing bounds checks in vc_do_resize() with rather strict
limits:
if (cols > VC_RESIZE_MAXCOL || lines > VC_RESIZE_MAXROW)
return -EINVAL;
Fixes: 0aec4867dc ("[PATCH] SVGATextMode fix")
Reference: CVE-2020-8647 and CVE-2020-8649
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
[danvet: augment commit message to point out overflow safety]
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200304022429.37738-1-zhangxiaoxu5@huawei.com
drm-misc-next for 5.7:
UAPI Changes:
- lima: Add support for heap buffers
Cross-subsystem Changes:
Core Changes:
- Implement mode_config mode_valid for memory constrained drivers
- Bus format negociation between bridges
- Consolidate fake vblank events for drivers without vblank interrupts
- drm/bufs: dma_alloc related cleanups
- drm/dp_mst: Various fixes
- drm/print: New drm_device based print helpers
- Thomas is a drm-misc maintainer now!
Driver Changes:
- DPMS cleanups for atomic drivers
- Removal of owner field in SPI tinydrm drivers
- Removal of explicit dependency on DT for tinydrm drivers
- Conversion to YAML schemas for DT bindings
- tidss: New driver
- virtio: various reworks and fixes
- Our usual dozen or so new panels or bridges
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200210093421.xu4sofldm6wm6xq6@gilmour.lan
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add SPDX license identifiers to all files which:
- Have no license information of any form
- Have MODULE_LICENCE("GPL*") inside which was used in the initial
scan/conversion to ignore the file
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add SPDX license identifiers to all files which:
- Have no license information of any form
- Have EXPORT_.*_SYMBOL_GPL inside which was used in the
initial scan/conversion to ignore the file
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
