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>
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Merge 5.9-rc3 into tty-next
We need the tty/serial fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are a few small TTY/Serial/vt fixes for 5.9-rc3
Included in here are:
- qcom serial fixes
- vt ioctl and core bugfixes
- pl011 serial driver fixes
- 8250 serial driver fixes
- other misc serial driver fixes
and for good measure:
- fbcon fix for syzbot found problem.
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-5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are a few small TTY/Serial/vt fixes for 5.9-rc3
Included in here are:
- qcom serial fixes
- vt ioctl and core bugfixes
- pl011 serial driver fixes
- 8250 serial driver fixes
- other misc serial driver fixes
and for good measure:
- fbcon fix for syzbot found problem.
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
tty: serial: imx: add dependence and build for earlycon
serial: samsung: Removes the IRQ not found warning
serial: 8250: change lock order in serial8250_do_startup()
serial: stm32: avoid kernel warning on absence of optional IRQ
serial: pl011: Fix oops on -EPROBE_DEFER
serial: pl011: Don't leak amba_ports entry on driver register error
serial: 8250_exar: Fix number of ports for Commtech PCIe cards
tty: serial: qcom_geni_serial: Drop __init from qcom_geni_console_setup
serial: qcom_geni_serial: Fix recent kdb hang
vt_ioctl: change VT_RESIZEX ioctl to check for error return from vc_resize()
fbcon: prevent user font height or width change from causing potential out-of-bounds access
vt: defer kfree() of vc_screenbuf in vc_do_resize()
This reverts commit b1c32fcfad, because
Syzkaller reports a use-after-free, a write in vcs_read:
BUG: KASAN: use-after-free in vcs_read_buf drivers/tty/vt/vc_screen.c:357 [inline]
BUG: KASAN: use-after-free in vcs_read+0xaa7/0xb40 drivers/tty/vt/vc_screen.c:449
Write of size 2 at addr ffff8880a8014000 by task syz-executor.5/16936
CPU: 1 PID: 16936 Comm: syz-executor.5 Not tainted 5.9.0-rc1-next-20200820-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
...
kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
vcs_read_buf drivers/tty/vt/vc_screen.c:357 [inline]
vcs_read+0xaa7/0xb40 drivers/tty/vt/vc_screen.c:449
There are two issues with the patch:
1) vcs_read rounds the 'count' *up* to an even number. So if we read odd
bytes from the header (3 bytes in the reproducer), the second byte of
a (2-byte/ushort) write to temporary con_buf won't fit. It is because
with the patch applied, we only subtract the real number read (3 bytes)
and not the whole header (4 bytes).
2) in this scenario, we perform unaligned accesses now: there are
2-byte/ushort writes to odd addresses. Due to the same reason as
above.
Revert this for now, re-think and retry later.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: syzbot+ad1f53726c3bd11180cb@syzkaller.appspotmail.com
Fixes: b1c32fcfad ("vc_screen: extract vcs_read_buf_header")
Cc: akpm@linux-foundation.org
Cc: nico@fluxnic.net
Link: https://lore.kernel.org/r/20200824095425.4376-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Do not undefine random words. I guess this was here as there were macros
with such generic names somewhere. I very doubt they still exist. So
drop these.
And remove a spare blank line.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-16-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The attribute header handling is terrible in vcs_read_buf. Separate it
to a new function and simply do memmove (of up to 4 bytes) to the start
of the con_buf -- if user seeked.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-15-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
And finally, move the attributes buffer handling to a separate function.
Leaving vcs_read quite compact.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-14-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The same as making write more readable, extract unicode handling from
vcs_read. The other two cases (w/ and w/o attributes) will follow.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-12-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Both tmp_count computations and the single use can be eliminated using
min(). Do so.
Side note: we need HEADER_SIZE to be unsigned for min() not to complain.
Fix that too as all its other uses do not mind.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-11-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* pos is derived from the passed ppos, so make it long enough, i.e.
loff_t
* attr and uni_mode are booleans, so...
* size is limited by vcs_size() which returns an int
* read, p, orig_count and this_round are always ">= 0" and "< size",
so uint is enough
* row, col, and max_col are derived from vc->vc_cols (uint) and p, so
make them uint too
* tmp_count is derived from this_round, so make it an uint too.
* use u16 * for org (instead of unsigned short *). No need to initialize
org too.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-10-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce a new inline function called vc_compile_le16 and do the shifts
and ORs there. Depending on LE x BE.
I tried cpu_to_le16, but it ends up with worse assembly on BE for
whatever reason -- the compiler seems to be unable to optimize the swap.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-9-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is the counterpart of the previous patch: here, we extract buffer
writing with attributes from vcs_write.
Now, there is no need for org to be initialized to NULL. The org0
check before update_region() confuses compilers, so check org instead.
It provides the same semantics. And it also eliminates the need for
initialization of org0.
We switch the branches of the attr 'if' too, as the inversion brings only
confusion now.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vcs_write is too long to be readable. Extract buffer handling w/o
attributes from there to a separate function.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ret can carry error codes, so make it signed, i.e. ssize_t
* pos is derived from the passed ppos, so make it long enough, i.e.
loff_t
* attr is a boolean, so...
* size is limited by vcs_size() which returns an int
* written, p, orig_count and this_round are always ">= 0" and "< size",
so uint is enough
* col and max_col are derived from vc->vc_cols (uint) and p, so make
them uint too
* place con_buf0 and con_buf declaration to a single line
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is weird to fetch the information from the inode over and over. Read
and write already have the needed information, so rewrite vcs_size to
accept a vc, attr and unicode and adapt vcs_lseek to that.
Also make sure all sites check the return value of vcs_size for errors.
And document it using kernel-doc.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
viewed is used as a flag, i.e. bool. So treat is as such in most of the
places. vcs_vc is handled in the next patch.
Note: the last parameter of invert_screen was misnamed in the
declaration since 1.1.92.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
That is:
1) call the parameter 'xy' to denote what it really is, not generic 'p'
2) tell the compiler and users that we expect an array:
* with at least 2 chars (static 2)
* which we don't modify in putconsxy (const)
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are many functions declared in selection.h which only read from
struct vc_data passed as a parameter. Make all those uses const to hint
the compiler a bit.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
syzbot is reporting UAF bug in set_origin() from vc_do_resize() [1], for
vc_do_resize() calls kfree(vc->vc_screenbuf) before calling set_origin().
Unfortunately, in set_origin(), vc->vc_sw->con_set_origin() might access
vc->vc_pos when scroll is involved in order to manipulate cursor, but
vc->vc_pos refers already released vc->vc_screenbuf until vc->vc_pos gets
updated based on the result of vc->vc_sw->con_set_origin().
Preserving old buffer and tolerating outdated vc members until set_origin()
completes would be easier than preventing vc->vc_sw->con_set_origin() from
accessing outdated vc members.
[1] https://syzkaller.appspot.com/bug?id=6649da2081e2ebdc65c0642c214b27fe91099db3
Reported-by: syzbot <syzbot+9116ecc1978ca3a12f43@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/1596034621-4714-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
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
...
- Prepare for tasklet API modernization (Romain Perier, Allen Pais, Kees Cook)
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Merge tag 'tasklets-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull tasklets API update from Kees Cook:
"These are the infrastructure updates needed to support converting the
tasklet API to something more modern (and hopefully for removal
further down the road).
There is a 300-patch series waiting in the wings to get set out to
subsystem maintainers, but these changes need to be present in the
kernel first. Since this has some treewide changes, I carried this
series for -next instead of paining Thomas with it in -tip, but it's
got his Ack.
This is similar to the timer_struct modernization from a while back,
but not nearly as messy (I hope). :)
- Prepare for tasklet API modernization (Romain Perier, Allen Pais,
Kees Cook)"
* tag 'tasklets-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
tasklet: Introduce new initialization API
treewide: Replace DECLARE_TASKLET() with DECLARE_TASKLET_OLD()
usb: gadget: udc: Avoid tasklet passing a global
It is very unlikely for processor to speculate on the func_table index.
The index is uchar and func_table is of size 256. So the compiler would
need to screw up and generate a really bad code.
But to stay on the safe side, forbid speculation on this user passed
index.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Jiri Kosina <jikos@kernel.org>
Link: https://lore.kernel.org/r/20200730105546.24268-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This converts all the existing DECLARE_TASKLET() (and ...DISABLED)
macros with DECLARE_TASKLET_OLD() in preparation for refactoring the
tasklet callback type. All existing DECLARE_TASKLET() users had a "0"
data argument, it has been removed here as well.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
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Merge 5.8-rc7 into tty-next
we need the tty/serial fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Link: https://lore.kernel.org/r/20200718133452.24290-1-grandmaster@al2klimov.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
syzbot is reporting general protection fault in do_con_write() [1] caused
by vc->vc_screenbuf == ZERO_SIZE_PTR caused by vc->vc_screenbuf_size == 0
caused by vc->vc_cols == vc->vc_rows == vc->vc_size_row == 0 caused by
fb_set_var() from ioctl(FBIOPUT_VSCREENINFO) on /dev/fb0 , for
gotoxy(vc, 0, 0) from reset_terminal() from vc_init() from vc_allocate()
from con_install() from tty_init_dev() from tty_open() on such console
causes vc->vc_pos == 0x10000000e due to
((unsigned long) ZERO_SIZE_PTR) + -1U * 0 + (-1U << 1).
I don't think that a console with 0 column or 0 row makes sense. And it
seems that vc_do_resize() does not intend to allow resizing a console to
0 column or 0 row due to
new_cols = (cols ? cols : vc->vc_cols);
new_rows = (lines ? lines : vc->vc_rows);
exception.
Theoretically, cols and rows can be any range as long as
0 < cols * rows * 2 <= KMALLOC_MAX_SIZE is satisfied (e.g.
cols == 1048576 && rows == 2 is possible) because of
vc->vc_size_row = vc->vc_cols << 1;
vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
in visual_init() and kzalloc(vc->vc_screenbuf_size) in vc_allocate().
Since we can detect cols == 0 or rows == 0 via screenbuf_size = 0 in
visual_init(), we can reject kzalloc(0). Then, vc_allocate() will return
an error, and con_write() will not be called on a console with 0 column
or 0 row.
We need to make sure that integer overflow in visual_init() won't happen.
Since vc_do_resize() restricts cols <= 32767 and rows <= 32767, applying
1 <= cols <= 32767 and 1 <= rows <= 32767 restrictions to vc_allocate()
will be practically fine.
This patch does not touch con_init(), for returning -EINVAL there
does not help when we are not returning -ENOMEM.
[1] https://syzkaller.appspot.com/bug?extid=017265e8553724e514e8
Reported-and-tested-by: syzbot <syzbot+017265e8553724e514e8@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/20200712111013.11881-1-penguin-kernel@I-love.SAKURA.ne.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty TIOCL_SETSEL ioctl allocates a memory buffer big enough for text
selection area. The maximum allowed console size is
VC_RESIZE_MAXCOL * VC_RESIZE_MAXROW == 32767*32767 == ~1GB and typical
MAX_ORDER is set to allow allocations lot less than than (circa 16MB).
So it is quite possible to trigger huge allocation (and syzkaller just
did that) which is going to fail (which is fine) with a backtrace in
mm/page_alloc.c at WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN)) and
this may trigger panic (if panic_on_warn is enabled) and
leak kernel addresses to dmesg.
This passes __GFP_NOWARN to kmalloc_array to avoid unnecessary user-
triggered WARN_ON. Note that the error is not ignored and
the warning is still printed.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Link: https://lore.kernel.org/r/20200617070444.116704-1-aik@ozlabs.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The vmemdup_user() function has no 2-factor argument form. Use array_size()
to check for the overflow.
Signed-off-by: Denis Efremov <efremov@linux.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200603102804.2110817-1-efremov@linux.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Synchronize with others and check perm directly in vt_k_ioctl.
We do not need to pass perm to do_fontx_ioctl and do_unimap_ioctl then.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-38-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We create a new vt_io_ioctl here and move there all the IO ioctls. This
makes vt_ioctl significantly smaller.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-32-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We create a new vt_k_ioctl here and move there all the K* ioctls. This
makes vt_ioctl significantly smaller.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-31-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
They were used for the first parameter of put_user. But put_user accepts
constants in the parameter and also determines the type only by the
second parameter. So we can safely drop these helpers and simplify the
code a bit.
Including the removal of set_int label.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-30-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is still a leftover from BKL, when we locked it around vt_ioctl's
code. We can return instead of breaks in the switch loop. And we can
return in case of errors too. This allows for sifting of the code to the
left in some cases.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-29-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All the attributes are bools, so do a simple shift instead of tests and
constants as bool is either 0 or 1.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-28-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There were too many parentheses in invert_screen, remove them and align
the code in invert_screen a bit.
No functional change intended.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-27-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The cursor code used to use magic constants, ANDs, ORs, and some macros.
Redefine all this to make some sense.
In particular:
* Drop CUR_DEFAULT, which is CUR_UNDERLINE. CUR_DEFAULT was used only
for cur_default variable initialization, so use CUR_UNDERLINE there to
make obvious what's the default.
* Drop CUR_HWMASK. Instead, define CUR_SIZE() which explains it more.
And use it all over the places.
* Define few more masks and bits which will be used in next patches
instead of magic constants.
* Define CUR_MAKE to build up cursor value.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-fbdev@vger.kernel.org
Link: https://lore.kernel.org/r/20200615074910.19267-25-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Format add_softcursor according to CodingStyle. Until now, it was a mess
of letters.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-24-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All the types are unsinged ints -- even the vpar passed to the function.
So unify them and use min() to compute count instead of explicit
comparison.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-23-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Nested ternary operators spread over 4 lines are really evil for
reading. Turn the outer one to proper 'if'. Now, we see, there is a
common path, so the code can be simplified. This way, the code is
understandable now.
Checked using symbolic execution (klee), that the old and new behaviors
are the same.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-22-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tetsuo Handa