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>
Invert the attribute on the only place, without the need of checking
'inverse'.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-21-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert (!(A && !B) || C) into (!A || B || C) to improve readability.
No functional changes, as was just proven by objdump.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-20-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vc_con_write_normal now handles the complex normal characters
processing. It is no longer a part of do_con_write. So this patch makes
do_con_write pretty clean and obvious.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-19-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move the control characters detection to a separate function dubbed
vc_is_control. It makes the 14 subexpressions a "bit" more readable. And
also simplifies next patches.
It moves also CTRL_ACTION and CTRL_ALWAYS to this new function, as they
are used exclusively here. While at it, these are converted to static
const variables.
And we use "& BIT()" instead of ">>" and "& 1".
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/20200615074910.19267-18-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that we reordered the code and the label, we can eliminate the
translation into a separate function. We call it vc_translate here.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-16-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This removes duplicated initialization of variables (after reordering
'c' initialization).
It will also allow for eliminating whole translation into a separate
function in the next patch.
Note that vc_state, vc_utf etc. are checked with every rescan now. But
they are immutable for non-control characters where rescan might be
only necessary.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-15-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We continue cleaning up do_con_write. This (hopefully) makes the
inversion code obvious.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-14-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code was too overcomplicated. Extract vc_sanitize_unicode to a
separate function and flatten the code. I believe the code is
straightforward now.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-13-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
do_con_write is complicated enough. Extract unicode handling to a
separate function. For do_con_write, 249 LOCs lowered to 183 lines.
Use diff -w -b to see the difference is neligible -- mostly whitespace
and use of 'return's instead of 'continue's.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-12-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use bools for rescan and inverse. And true/false accordingly.
Use u8 for width instead of uint8_t.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-11-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vc_translate is used only in vt.c, so move the definition from a header
there. Also, it used to be a macro, so be modern and make a static
inline from it. This makes the code actually readable.
And as a preparation for next patches, rename it to vc_translate_ascii.
vc_translate will be a wrapper for both unicode and this one.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-10-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
VT100ID is unused, but defined twice. Kill it.
VT102ID is used only in respond_ID. Define there a variable with proper
type and use that instead. Then drop both defines of VT102ID too.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-9-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pass the length of a string to respond_string and use
tty_insert_flip_string instead of a loop with tty_insert_flip_char. This
simplifies the processing on the tty side.
The added strlens are optimized during constant folding and propagation
and the result are proper constants in assembly.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vc_tab_stop is used as a bitmap, but defined as an unsigned int array.
Switch it to bitmap and convert all users to the bitmap interface.
Note the difference in behavior! We no longer mask the top 24 bits away
from x, hence we do not wrap tabs at 256th column. Instead, we silently
drop attempts to set a tab behind 256 columns. And we will also seek by
'\t' to the rightmost column, when behind that boundary. I do not think
the original behavior was desired and that someone relies on that. If
this turns out to be the case, we can change the added 'if's back to
masks here and there instead...
(Or we can increase the limit as fb consoles now have 240 chars here.
And they could have more with higher than my resolution, of course.)
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Declare Gx_charset[2] instead of G0_charset and G1_charset. It makes
the code simpler (without ternary operators).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code for setting G0 and G1 is duplicated -- for each of them. Move
the code to a separate function (vc_setGx) and distinguish the two cases
by a parameter.
Change if-else-if to switch which allows for slightly better
optimization (decision tree).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code currently uses bitfields to store true-false values. Switch all
of that to bools. Apart from the cleanup, it saves 20B of code as many
shifts, ANDs, and ORs became simple movzb's.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-3-jslaby@suse.cz
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>
When k_ascii is invoked several times in a row there is a potential for
signed integer overflow:
UBSAN: Undefined behaviour in drivers/tty/vt/keyboard.c:888:19 signed integer overflow:
10 * 1111111111 cannot be represented in type 'int'
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.11 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xce/0x128 lib/dump_stack.c:118
ubsan_epilogue+0xe/0x30 lib/ubsan.c:154
handle_overflow+0xdc/0xf0 lib/ubsan.c:184
__ubsan_handle_mul_overflow+0x2a/0x40 lib/ubsan.c:205
k_ascii+0xbf/0xd0 drivers/tty/vt/keyboard.c:888
kbd_keycode drivers/tty/vt/keyboard.c:1477 [inline]
kbd_event+0x888/0x3be0 drivers/tty/vt/keyboard.c:1495
While it can be worked around by using check_mul_overflow()/
check_add_overflow(), it is better to introduce a separate flag to
signal that number pad is being used to compose a symbol, and
change type of the accumulator from signed to unsigned, thus
avoiding undefined behavior when it overflows.
Reported-by: Kyungtae Kim <kt0755@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200525232740.GA262061@dtor-ws
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
By directly using kfree() in different places we risk missing one if
it is switched to using vfree(), especially if the corresponding
vmalloc() is hidden away within a common abstraction.
Oh wait, that's exactly what happened here.
So let's fix this by creating a common abstraction for the free case
as well.
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Reported-by: syzbot+0bfda3ade1ee9288a1be@syzkaller.appspotmail.com
Fixes: 9a98e7a80f ("vt: don't use kmalloc() for the unicode screen buffer")
Cc: <stable@vger.kernel.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.2005021043110.2671@knanqh.ubzr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code in vc_do_resize() bounds the memory allocation size to avoid
exceeding MAX_ORDER down the kzalloc() call chain and generating a
runtime warning triggerable from user space. However, not only is it
unwise to use a literal value here, but MAX_ORDER may also be
configurable based on CONFIG_FORCE_MAX_ZONEORDER.
Let's use KMALLOC_MAX_SIZE instead.
Note that prior commit bb1107f7c6 ("mm, slab: make sure that
KMALLOC_MAX_SIZE will fit into MAX_ORDER") the KMALLOC_MAX_SIZE value
could not be relied upon.
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Cc: <stable@vger.kernel.org> # v4.10+
Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.2003281702410.2671@knanqh.ubzr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Even if the actual screen size is bounded in vc_do_resize(), the unicode
buffer is still a little more than twice the size of the glyph buffer
and may exceed MAX_ORDER down the kmalloc() path. This can be triggered
from user space.
Since there is no point having a physically contiguous buffer here,
let's avoid the above issue as well as reducing pressure on high order
allocations by using vmalloc() instead.
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Cc: <stable@vger.kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.2003282214210.2671@knanqh.ubzr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Let's put it to a separate function, named vc_selection_store_chars.
Again, this makes vc_do_selection a bit shorter and more readable.
Having 4 local variables instead of 12 (5.6-rc1) looks much better now.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200415093608.10348-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Handle these actions:
* poking console
* TIOCL_SELCLEAR
* TIOCL_SELMOUSEREPORT
* start/end precomputation
* clear_selection if the console changed
in a separate function, thus making __set_selection_kernel way shorter
and more readable. The function still needs dissection, but we are
approaching.
This includes introduction of vc_selection and renaming
__set_selection_kernel to vc_do_selection.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200415093608.10348-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vt_in_use() dereferences console_driver->ttys[i] without proper locking.
This is broken because the tty can be closed and freed concurrently.
We could fix this by using 'READ_ONCE(console_driver->ttys[i]) != NULL'
and skipping the check of tty_struct::count. But, looking at
console_driver->ttys[i] isn't really appropriate anyway because even if
it is NULL the tty can still be in the process of being closed.
Instead, fix it by making vt_in_use() require console_lock() and check
whether the vt is allocated and has port refcount > 1. This works since
following the patch "vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use
virtual console" the port refcount is incremented while the vt is open.
Reproducer (very unreliable, but it worked for me after a few minutes):
#include <fcntl.h>
#include <linux/vt.h>
int main()
{
int fd, nproc;
struct vt_stat state;
char ttyname[16];
fd = open("/dev/tty10", O_RDONLY);
for (nproc = 1; nproc < 8; nproc *= 2)
fork();
for (;;) {
sprintf(ttyname, "/dev/tty%d", rand() % 8);
close(open(ttyname, O_RDONLY));
ioctl(fd, VT_GETSTATE, &state);
}
}
KASAN report:
BUG: KASAN: use-after-free in vt_in_use drivers/tty/vt/vt_ioctl.c:48 [inline]
BUG: KASAN: use-after-free in vt_ioctl+0x1ad3/0x1d70 drivers/tty/vt/vt_ioctl.c:657
Read of size 4 at addr ffff888065722468 by task syz-vt2/132
CPU: 0 PID: 132 Comm: syz-vt2 Not tainted 5.6.0-rc5-00130-g089b6d3654916 #13
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014
Call Trace:
[...]
vt_in_use drivers/tty/vt/vt_ioctl.c:48 [inline]
vt_ioctl+0x1ad3/0x1d70 drivers/tty/vt/vt_ioctl.c:657
tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660
[...]
Allocated by task 136:
[...]
kzalloc include/linux/slab.h:669 [inline]
alloc_tty_struct+0x96/0x8a0 drivers/tty/tty_io.c:2982
tty_init_dev+0x23/0x350 drivers/tty/tty_io.c:1334
tty_open_by_driver drivers/tty/tty_io.c:1987 [inline]
tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035
[...]
Freed by task 41:
[...]
kfree+0xbf/0x200 mm/slab.c:3757
free_tty_struct+0x8d/0xb0 drivers/tty/tty_io.c:177
release_one_tty+0x22d/0x2f0 drivers/tty/tty_io.c:1468
process_one_work+0x7f1/0x14b0 kernel/workqueue.c:2264
worker_thread+0x8b/0xc80 kernel/workqueue.c:2410
[...]
Fixes: 4001d7b7fc ("vt: push down the tty lock so we can see what is left to tackle")
Cc: <stable@vger.kernel.org> # v3.4+
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200322034305.210082-3-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The VT_DISALLOCATE ioctl can free a virtual console while tty_release()
is still running, causing a use-after-free in con_shutdown(). This
occurs because VT_DISALLOCATE considers a virtual console's
'struct vc_data' to be unused as soon as the corresponding tty's
refcount hits 0. But actually it may be still being closed.
Fix this by making vc_data be reference-counted via the embedded
'struct tty_port'. A newly allocated virtual console has refcount 1.
Opening it for the first time increments the refcount to 2. Closing it
for the last time decrements the refcount (in tty_operations::cleanup()
so that it happens late enough), as does VT_DISALLOCATE.
Reproducer:
#include <fcntl.h>
#include <linux/vt.h>
#include <sys/ioctl.h>
#include <unistd.h>
int main()
{
if (fork()) {
for (;;)
close(open("/dev/tty5", O_RDWR));
} else {
int fd = open("/dev/tty10", O_RDWR);
for (;;)
ioctl(fd, VT_DISALLOCATE, 5);
}
}
KASAN report:
BUG: KASAN: use-after-free in con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278
Write of size 8 at addr ffff88806a4ec108 by task syz_vt/129
CPU: 0 PID: 129 Comm: syz_vt Not tainted 5.6.0-rc2 #11
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014
Call Trace:
[...]
con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278
release_tty+0xa8/0x410 drivers/tty/tty_io.c:1514
tty_release_struct+0x34/0x50 drivers/tty/tty_io.c:1629
tty_release+0x984/0xed0 drivers/tty/tty_io.c:1789
[...]
Allocated by task 129:
[...]
kzalloc include/linux/slab.h:669 [inline]
vc_allocate drivers/tty/vt/vt.c:1085 [inline]
vc_allocate+0x1ac/0x680 drivers/tty/vt/vt.c:1066
con_install+0x4d/0x3f0 drivers/tty/vt/vt.c:3229
tty_driver_install_tty drivers/tty/tty_io.c:1228 [inline]
tty_init_dev+0x94/0x350 drivers/tty/tty_io.c:1341
tty_open_by_driver drivers/tty/tty_io.c:1987 [inline]
tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035
[...]
Freed by task 130:
[...]
kfree+0xbf/0x1e0 mm/slab.c:3757
vt_disallocate drivers/tty/vt/vt_ioctl.c:300 [inline]
vt_ioctl+0x16dc/0x1e30 drivers/tty/vt/vt_ioctl.c:818
tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660
[...]
Fixes: 4001d7b7fc ("vt: push down the tty lock so we can see what is left to tackle")
Cc: <stable@vger.kernel.org> # v3.4+
Reported-by: syzbot+522643ab5729b0421998@syzkaller.appspotmail.com
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200322034305.210082-2-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Shift cases one level left. This makes the code more readable and some
lines need not wrap anymore.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200316065911.11024-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We have a helper called rounddown for these modulo computations. So use
it.
No functional change intended and "objdump -d" proves that.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200316065911.11024-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Instead of awkward ternary operator with comparison, use simple min()
for blankinterval and vesa_off_interval.
No functional change intended and "objdump -d" proves that.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200316065911.11024-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The merge commit cb05c6c82f (Merge 5.6-rc5 into tty-next) introduced a
double lock to set_selection_kernel. vc_sel.lock is locked both in
set_selection_kernel and its callee __set_selection_kernel now.
Remove the latter.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/r/20200316064544.4799-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The vc_cons_allocated() checks in vt_ioctl() and vt_compat_ioctl() are
unnecessary because they can only be reached by calling ioctl() on an
open tty, which implies the corresponding virtual console is allocated.
And even if the virtual console *could* be freed concurrently, then
these checks would be broken since they aren't done under console_lock,
and the vc_data is dereferenced before them anyway.
So, remove these unneeded checks to avoid confusion.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200224080326.295046-1-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The might_sleep() in do_con_write() is redundant because console_lock()
already contains might_sleep(). Remove it.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200224073450.292892-1-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We need the vt fixes in here and it resolves a merge issue with
drivers/tty/vt/selection.c
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Shift the cases one level left as this is how we are supposed to write
the switch-case code according to the CodingStyle.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-9-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is declared in vt_kern.h, so no need to declare it in selection.c
which includes the header.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move all the selection global variables to a structure vc_selection,
instantiated as vc_sel. This helps to group all the variables together
and see what should be protected by the embedded lock too.
It might be used later also for per-console selection support.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
use_unicode needs not be global. It is used only in set_selection_kernel
and sel_pos (a callee). It is also always set there prior calling
sel_pos. So make use_unicode local and rename it to plain shorter
"unicode". Finally, propagate it to sel_pos via parameter.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
multiplier and mode are not actually needed:
* multiplier is used only in kmalloc_array, so use "use_unicode ? 4 : 1"
directly
* mode is used only to assign a bool in this manner:
if (cond)
x = true;
else
x = false;
So do "x = cond" directly.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We need to nest the console lock in sel_lock, so we have to push it down
a bit. Fortunately, the callers of set_selection_* just lock the console
lock around the function call. So moving it down is easy.
In the next patch, we switch the order.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Fixes: 07e6124a1a ("vt: selection, close sel_buffer race")
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200228115406.5735-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These two were macros. Switch them to static inlines, so that it's more
understandable what they are doing.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Avoid global variables (namely sel_cons) by introducing vc_is_sel. It
checks whether the parameter is the current selection console. This will
help putting sel_cons to a struct later.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
syzkaller reported this UAF:
BUG: KASAN: use-after-free in n_tty_receive_buf_common+0x2481/0x2940 drivers/tty/n_tty.c:1741
Read of size 1 at addr ffff8880089e40e9 by task syz-executor.1/13184
CPU: 0 PID: 13184 Comm: syz-executor.1 Not tainted 5.4.7 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
...
kasan_report+0xe/0x20 mm/kasan/common.c:634
n_tty_receive_buf_common+0x2481/0x2940 drivers/tty/n_tty.c:1741
tty_ldisc_receive_buf+0xac/0x190 drivers/tty/tty_buffer.c:461
paste_selection+0x297/0x400 drivers/tty/vt/selection.c:372
tioclinux+0x20d/0x4e0 drivers/tty/vt/vt.c:3044
vt_ioctl+0x1bcf/0x28d0 drivers/tty/vt/vt_ioctl.c:364
tty_ioctl+0x525/0x15a0 drivers/tty/tty_io.c:2657
vfs_ioctl fs/ioctl.c:47 [inline]
It is due to a race between parallel paste_selection (TIOCL_PASTESEL)
and set_selection_user (TIOCL_SETSEL) invocations. One uses sel_buffer,
while the other frees it and reallocates a new one for another
selection. Add a mutex to close this race.
The mutex takes care properly of sel_buffer and sel_buffer_lth only. The
other selection global variables (like sel_start, sel_end, and sel_cons)
are protected only in set_selection_user. The other functions need quite
some more work to close the races of the variables there. This is going
to happen later.
This likely fixes (I am unsure as there is no reproducer provided) bug
206361 too. It was marked as CVE-2020-8648.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: syzbot+59997e8d5cbdc486e6f6@syzkaller.appspotmail.com
References: https://bugzilla.kernel.org/show_bug.cgi?id=206361
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200210081131.23572-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When pasting a selection to a vt, the task is set as INTERRUPTIBLE while
waiting for a tty to unthrottle. But signals are not handled at all.
Normally, this is not a problem as tty_ldisc_receive_buf receives all
the goods and a user has no reason to interrupt the task.
There are two scenarios where this matters:
1) when the tty is throttled and a signal is sent to the process, it
spins on a CPU until the tty is unthrottled. schedule() does not
really echedule, but returns immediately, of course.
2) when the sel_buffer becomes invalid, KASAN prevents any reads from it
and the loop simply does not proceed and spins forever (causing the
tty to throttle, but the code never sleeps, the same as above). This
sometimes happens as there is a race in the sel_buffer handling code.
So add signal handling to this ioctl (TIOCL_PASTESEL) and return -EINTR
in case a signal is pending.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200210081131.23572-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit a6dbe44275 ("vt: perform safe console erase in the right
order") provided fixes to an earlier commit by gathering all console
scrollback flushing operations in a function of its own. This includes
the invocation of vc_sw->con_switch() as previously done through a
update_screen() call. That commit failed to carry over the
con_is_visible() conditional though, as well as cursor handling, which
caused problems when "\e[3J" was written to a background console.
One could argue for preserving the call to update_screen(). However
this does far more than we need, and it is best to remove scrollback
assumptions from it. Instead let's gather the minimum needed to actually
perform scrollback flushing properly in that one place.
While at it, let's document the vc_sw->con_switch() side effect being
relied upon.
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Reported-and-tested-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.2001281205560.1655@knanqh.ubzr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.
It is typically useful in scripts/Makefile because it allows Kbuild to
selectively compile host programs based on the kernel configuration.
This commit renames like follows:
always -> always-y
hostprogs-y -> hostprogs
So, scripts/Makefile will look like this:
always-$(CONFIG_BUILD_BIN2C) += ...
always-$(CONFIG_KALLSYMS) += ...
...
hostprogs := $(always-y) $(always-m)
I think this makes more sense because a host program is always a host
program, irrespective of the kernel configuration. We want to specify
which ones to compile by CONFIG options, so always-y will be handier.
The "always", "hostprogs-y", "hostprogs-m" will be kept for backward
compatibility for a while.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Commit 3e795de763 ("[PATCH] VT binding: Add binding/unbinding support
for the VT console") introduced a code comment claiming that
"do_take_over_console is basically a register followed by unbind".
However the function actually performs a register followed by *bind*.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Antonino A. Daplas <adaplas@gmail.com>
Link: https://lore.kernel.org/r/a500f005ba7013ca8165a6d42f59b2183d56114f.1578574427.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the arch setup code hasn't initialized conswitchp yet, set it to
dummy_con in con_init. This will allow us to drop the dummy_con
initialization that's done in almost every architecture.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20191218214506.49252-3-nivedita@alum.mit.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
scripts/conmakehash is only used for generating
drivers/tty/vt/consolemap_deftbl.c
Move it to the related directory.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20191217110633.8796-1-masahiroy@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit d21b0be246 ("vt: introduce unicode mode for /dev/vcs") guarded
against using devices containing attributes as this is not yet
implemented. It however failed to guard against writes to any devices
as this is also unimplemented.
Reported-by: Or Cohen <orcohen@paloaltonetworks.com>
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Cc: <stable@vger.kernel.org> # v4.19+
Cc: Jiri Slaby <jslaby@suse.com>
Fixes: d21b0be246 ("vt: introduce unicode mode for /dev/vcs")
Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.1911051030580.30289@knanqh.ubzr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Do not try to handle keycodes that are too big, otherwise we risk doing
out-of-bounds writes:
BUG: KASAN: global-out-of-bounds in clear_bit include/asm-generic/bitops-instrumented.h:56 [inline]
BUG: KASAN: global-out-of-bounds in kbd_keycode drivers/tty/vt/keyboard.c:1411 [inline]
BUG: KASAN: global-out-of-bounds in kbd_event+0xe6b/0x3790 drivers/tty/vt/keyboard.c:1495
Write of size 8 at addr ffffffff89a1b2d8 by task syz-executor108/1722
...
kbd_keycode drivers/tty/vt/keyboard.c:1411 [inline]
kbd_event+0xe6b/0x3790 drivers/tty/vt/keyboard.c:1495
input_to_handler+0x3b6/0x4c0 drivers/input/input.c:118
input_pass_values.part.0+0x2e3/0x720 drivers/input/input.c:145
input_pass_values drivers/input/input.c:949 [inline]
input_set_keycode+0x290/0x320 drivers/input/input.c:954
evdev_handle_set_keycode_v2+0xc4/0x120 drivers/input/evdev.c:882
evdev_do_ioctl drivers/input/evdev.c:1150 [inline]
In this case we were dealing with a fuzzed HID device that declared over
12K buttons, and while HID layer should not be reporting to us such big
keycodes, we should also be defensive and reject invalid data ourselves as
well.
Reported-by: syzbot+19340dff067c2d3835c0@syzkaller.appspotmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191122204220.GA129459@dtor-ws
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Not really harmful not to, but also not harm in grabbing the lock. And
this shuts up a new WARNING I introduced in commit ddde3c18b7 ("vt:
More locking checks").
Reported-by: Jens Remus <jremus@linux.ibm.com>
Cc: linux-kernel@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-fbdev@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Martin Hostettler <textshell@uchuujin.de>
Cc: Adam Borowski <kilobyte@angband.pl>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sam Ravnborg <sam@ravnborg.org>
Fixes: ddde3c18b7 ("vt: More locking checks")
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Tested-by: Jens Remus <jremus@linux.ibm.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/r/20190718080903.22622-1-daniel.vetter@ffwll.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
I honestly have no idea what the subtle differences between
con_is_visible, con_is_fg (internal to vt.c) and con_is_bound are. But
it looks like both vc->vc_display_fg and con_driver_map are protected
by the console_lock, so probably better if we hold that when checking
this.
To do that I had to deinline the con_is_visible function.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Martin Hostettler <textshell@uchuujin.de>
Cc: Adam Borowski <kilobyte@angband.pl>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-5-daniel.vetter@ffwll.ch
For symmetry reasons with do_unblank_screen, except without the
oops_in_progress special case.
Just a drive-by annotation while I'm trying to untangle the fbcon vs.
fbdev screen blank/unblank maze.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Adam Borowski <kilobyte@angband.pl>
Cc: Martin Hostettler <textshell@uchuujin.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-4-daniel.vetter@ffwll.ch
After memory allocation failure vc_allocate() doesn't clean up data
which has been initialized in visual_init(). In case of fbcon this
leads to divide-by-0 in fbcon_init() on next open of the same tty.
memory allocation in vc_allocate() may fail here:
1097: vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL);
on next open() fbcon_init() skips vc_font.data initialization:
1088: if (!p->fontdata) {
division by zero in fbcon_init() happens here:
1149: new_cols /= vc->vc_font.width;
Additional check is needed in fbcon_deinit() to prevent
usage of uninitialized vc_screenbuf:
1251: if (vc->vc_hi_font_mask && vc->vc_screenbuf)
1252: set_vc_hi_font(vc, false);
Crash:
#6 [ffffc90001eafa60] divide_error at ffffffff81a00be4
[exception RIP: fbcon_init+463]
RIP: ffffffff814b860f RSP: ffffc90001eafb18 RFLAGS: 00010246
...
#7 [ffffc90001eafb60] visual_init at ffffffff8154c36e
#8 [ffffc90001eafb80] vc_allocate at ffffffff8154f53c
#9 [ffffc90001eafbc8] con_install at ffffffff8154f624
...
Signed-off-by: Grzegorz Halat <ghalat@redhat.com>
Reviewed-by: Oleksandr Natalenko <oleksandr@redhat.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here is the "big" set of tty/serial driver patches for 5.2-rc1.
It's really pretty small, not much happening in this portion of the
kernel at the moment. When the "highlight" is the movement of the
documentation from .txt to .rst files, it's a good merge window.
There's a number of small fixes and updates over the various serial
drivers, and a new "tty null" driver for those embedded systems that
like to make things even smaller and not break things.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXNKvrw8cZ3JlZ0Brcm9h
aC5jb20ACgkQMUfUDdst+ynR2wCfTrWM9Qm7oA1hgWeYZiLTrnYnOtsAoK4a629W
o7AAyVf8RJ4jdWaSgOqx
=9Dy/
-----END PGP SIGNATURE-----
Merge tag 'tty-5.2-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 patches for 5.2-rc1.
It's really pretty small, not much happening in this portion of the
kernel at the moment. When the "highlight" is the movement of the
documentation from .txt to .rst files, it's a good merge window.
There's a number of small fixes and updates over the various serial
drivers, and a new "tty null" driver for those embedded systems that
like to make things even smaller and not break things.
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (45 commits)
tty: serial: add driver for the SiFive UART
dt-bindings: serial: add documentation for the SiFive UART driver
serial: uartps: Add support for cts-override
dt-bindings: xilinx-uartps: Add support for cts-override
serial: milbeaut_usio: Fix error handling in probe and remove
tty: rocket: deprecate the rp_ioctl
tty: rocket: Remove RCPK_GET_STRUCT ioctl
tty: update obsolete termios comment
tty: serial_core: fix error code returned by uart_register_driver()
serial: 8250-mtk: modify baudrate setting
serial: 8250-mtk: add follow control
docs: serial: convert docs to ReST and rename to *.rst
serial: 8250_exar: Adjust IOT2000 matching
TTY: serial_core, add ->install
serial: Fix using plain integer instead of Null pointer
tty:serial_core: Spelling mistake
tty: Add NULL TTY driver
tty: vt: keyboard: Allow Unicode compose base char
Revert "tty: fix NULL pointer issue when tty_port ops is not set"
serial: Add Milbeaut serial control
...
This patch breaks set_selection() into two functions so that when
called from kernel, copy_from_user() can be avoided. The two functions
are called set_selection_user() and set_selection_kernel() in order to
be explicit about their purposes. This also means updating any
references to set_selection() and fixing for name change. It also
exports set_selection_kernel() and paste_selection().
These changes are used the following patch where speakup's selection
functionality calls into the above functions, thereby doing away with
parallel implementation.
Signed-off-by: Okash Khawaja <okash.khawaja@gmail.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Tested-by: Gregory Nowak <greg@gregn.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The patch a6dbe44275 ("vt: perform safe console erase in the right
order") introduced a bug. The conditional do_update_region() was
replaced by a call to update_region() that does contain the conditional
already, but with unwanted extra side effects such as restoring the cursor
drawing.
In order to reproduce the bug:
- use framebuffer console with the AMDGPU driver
- type "links" to start the console www browser
- press 'q' and space to exit links
Now the cursor will be permanently visible in the center of the
screen. It will stay there until something overwrites it.
The bug goes away if we change update_region() back to the conditional
do_update_region().
[ nico: reworded changelog ]
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Nicolas Pitre <nico@fluxnic.net>
Cc: stable@vger.kernel.org
Fixes: a6dbe44275 ("vt: perform safe console erase in the right order")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pass Unicode character to k_unicode handler function to honor possible
accent_table definition.
With introduction of KDSKBDIACRUC ioctl, it has been possible to set
compose characters (diacr, base and result) to any Unicode character
(below 0xf000 code point) as defined in struct kbdiacruc.
But it does not work with characters beyond Latin-1 as base, because
they are printed early and not passed to any of the handler functions,
thus breaking compose and dead keys.
It affects keyboard layouts defining such characters on level 1 and
relying on dead keys to access level 3 (e.g., lv-modern with some
modifications for extra characters on level 3 for ē, ā and ī keys).
Signed-off-by: Reinis Danne <rei4dan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
GIO_UNIMAP can easily result in a high order allocation,
seen 6th order allocation on radeondrmfb:
fbcon: radeondrmfb (fb0) is primary device
Console: switching to colour frame buffer device 160x64
radeon 0000:01:05.0: fb0: radeondrmfb frame buffer device
WARNING: CPU: 0 PID: 78661 at mm/page_alloc.c:3532
__alloc_pages_nodemask+0x1b1/0x600
order 6 >= 3, gfp 0x40d0
The warning is generated by a debug patch.
At the same time it's safe to use kvmalloc() for allocation in
con_get_unimap(), so let's do the substitution.
And do the same for con_set_unimap().
Signed-off-by: Konstantin Khorenko <khorenko@virtuozzo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There were a few straggling files under drivers/tty/ that did not have
any SPDX identifier either because they entered the tree recently, or
they somehow missed the mass-tagging of commit b24413180f ("License
cleanup: add SPDX GPL-2.0 license identifier to files with no license")
This commit follows the same rule as b24413180f ("License cleanup: add
SPDX GPL-2.0 license identifier to files with no license") where files
without any specified license in them fall under GPL-2.0 as the correct
license for the individual file. Add that identifier to these remaining
files so that we don't have to guess at the license of them in the
future.
Cc: Jiri Slaby <jslaby@suse.com>
Cc: "David S. Miller" <davem@davemloft.net>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Both /dev/vcs and /dev/vcs0 were in use in the past, but these days
/dev/vcs0 is mostly historical curiosity.
* "/dev/vcs" is the name that has always been in the Linux allocated
devices list.
* "vcs" is the device name in sysfs since Linux v2.6.12.
* MAKEDEV(1) in Debian used to create /dev/vcs0 only, but /dev/vcs was
added in 1999: https://bugs.debian.org/45698
* MAKEDEV(1) in RedHat switched from /dev/vcs0 to /dev/vcs in 2000:
* Fri Oct 20 2000 Nalin Dahyabhai <nalin@redhat.com>
- change vcs0 to vcs (ditto for vcsa0)
Signed-off-by: Jakub Wilk <jwilk@jwilk.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Previously, in the userspace, it was possible to use the "setterm" command
from util-linux to blank the VT console by default, using the following
command.
According to the man page,
> The force option keeps the screen blank even if a key is pressed.
It was implemented by calling TIOCL_BLANKSCREEN.
case BLANKSCREEN:
ioctlarg = TIOCL_BLANKSCREEN;
if (ioctl(STDIN_FILENO, TIOCLINUX, &ioctlarg))
warn(_("cannot force blank"));
break;
However, after Linux 4.12, this command ceased to work anymore, which is
unexpected. By inspecting the kernel source, it shows that the issue was
triggered by the side-effect from commit a4199f5eb8 ("tty: Disable
default console blanking interval").
The console blanking is implemented by function do_blank_screen() in vt.c:
"blank_state" will be initialized to "blank_normal_wait" in con_init() if
AND ONLY IF ("blankinterval" > 0). If "blankinterval" is 0, "blank_state"
will be "blank_off" (== 0), and a call to do_blank_screen() will always
abort, even if a forced blanking is required from the user by calling
TIOCL_BLANKSCREEN, the console won't be blanked.
This behavior is unexpected from a user's point-of-view, since it's not
mentioned in any documentation. The setterm man page suggests it will
always work, and the kernel comments in uapi/linux/tiocl.h says
> /* keep screen blank even if a key is pressed */
> #define TIOCL_BLANKSCREEN 14
To fix it, we simply remove the "blank_state != blank_off" check, as
pointed out by Nicolas Pitre, this check doesn't logically make sense
and it's safe to remove.
Suggested-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Fixes: a4199f5eb8 ("tty: Disable default console blanking interval")
Signed-off-by: Yifeng Li <tomli@tomli.me>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 4b4ecd9cb8 ("vt: Perform safe console erase only once") removed
what appeared to be an extra call to scr_memsetw(). This missed the fact
that set_origin() must be called before clearing the screen otherwise
old screen content gets restored on the screen when using vgacon. Let's
fix that by moving all the scrollback handling to flush_scrollback()
where it logically belongs, and invoking it before the actual screen
clearing in csi_J(), making the code simpler in the end.
Reported-by: Matthew Whitehead <tedheadster@gmail.com>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Matthew Whitehead <tedheadster@gmail.com>
Fixes: 4b4ecd9cb8 ("vt: Perform safe console erase only once")
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
csi sequences can contain subparameters delimited by ':' characters. For
now just ignore the whole sequence in this case. Such sequences are used by
more capable terminal implementations with T.416 high color modes or
extended underline rendition attributes.
Also ignore sequences with private use characters '?', '>', '='
and '>' that are not at the initial position.
Signed-off-by: Martin Hostettler <textshell@uchuujin.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Various csi sequences contain intermediate characters between the
parameters and the final character. Introduce a additional state that
cleanly ignores these sequences.
This allows the vt to ignore these sequences used by more capable
terminal implementations such as "request mode", etc.
Signed-off-by: Martin Hostettler <textshell@uchuujin.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Private sequences can start with '>', '=' and (in theory) '<'.
Implement correct parsing for these. The newly parsable sequences are
cleanly ignored as it is customary with terminal emulators.
This allows the vt to ignore various sequences used by more capable
terminal implementations such as "Secondary Device Attributes",
"Tertiary Device Attributes" and various advanced configuration commands
that don't have dedicated terminfo entries.
Signed-off-by: Martin Hostettler <textshell@uchuujin.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The vc_ques keeps track if a csi sequence is a private DEC control
function beginning with '?'. Nowadays some private control functions
begin with '>' and '='. Switch the code to instead use a new 3-bit
vc_priv that allows for all private use parameter prefixes.
Signed-off-by: Martin Hostettler <textshell@uchuujin.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a plan to build the kernel with -Wimplicit-fallthrough and
these places in the code produced warnings (W=1). Fix them up.
This commit remove the following warning:
drivers/tty/vt/vt.c:2112:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/tty/vt/vt.c:2237:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Acked-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Restore and document the forced initial POLLPRI event reporting when
poll() is used for the first time. This used to be the implemented
behavior before recent changes. Because of the way poll() is implemented,
this prevents losing an event happening between the last read() and the
first poll() invocation.
Since poll() for /dev/vcs* was not always supported, user space probes
for its availability as follows:
int fd = open("/dev/vcsa", O_RDONLY);
struct pollfd p = { .fd = fd, .events = POLLPRI };
available = (poll(&p, 1, 0) == 1);
Semantically, it makes sense to signal the first event as such even if
it might be spurious. The screen could be modified, and modified back
to its initial state before we get to read it, so users must be prepared
for that anyway.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We use POLLPRI not POLLIN to wait for data with poll() as there is
never any incoming data stream per se. Let's use the same semantic
with fasync() for consistency, including the fact that a vt may go away.
No known user space ever relied on the SIGIO reason so far, let alone
FASYNC, so the risk of breakage is pretty much nonexistent.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When VT_DISALLOCATE is used on a vt, user space waiting with poll() on
the corresponding /dev/vcs device is not awakened. This is now fixed by
returning POLLHUP|POLLERR to user space.
Also, in the normal screen update case, we don't set POLLERR anymore as
POLLPRI alone is a much more logical response in a non-error situation,
saving some confusion on the user space side. The only known user app
making use of poll() on /dev/vcs* is BRLTTY which is known to cope with
that change already, so the risk of breakage is pretty much nonexistent.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The /dev/vcsa* devices have a fixed char-sized header that stores the
screen geometry and cursor location. Let's make sure it doesn't contain
random garbage when those values exceed 255. If ever it becomes necessary
to convey larger screen info to user space then a larger header in the
not-yet-implemented /dev/vcsua* devices should be considered.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
User space using poll() on /dev/vcs devices are not awaken when a
screen size change occurs. Let's fix that.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Every invocation of notify_write() and notify_update() is performed
under the console lock, except for one case. Let's fix that.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When kernel messages are printed to the console, they appear blank on
the unicode screen. This is because vt_console_print() is lacking a call
to vc_uniscr_putc(). However the later function assumes vc->vc_x is
always up to date when called, which is not the case here as
vt_console_print() uses it to mark the beginning of the display update.
This patch reworks (and simplifies) vt_console_print() so that vc->vc_x
is always valid and keeps the start of display update in a local variable
instead, which finally allows for adding the missing vc_uniscr_putc()
call.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are some small tty fixes for 4.20-rc2
One of these missed the original 4.19-final release, I missed that I
hadn't done a pull request for it as it was in linux-next and my branch
for a long time, that's my fault.
The others are small, fixing some reported issues and finally fixing the
termios mess for alpha so that glibc has a chance to implement some
missing functionality that has been pending for many years now.
All of these have been in linux-next with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCW+cpjw8cZ3JlZ0Brcm9h
aC5jb20ACgkQMUfUDdst+ymcQQCgt4IbK1wm/bxZqikhg64GS7J7IdkAoLoK1gKi
Sq+KsJX2qr4GuAcxJIjr
=uyeQ
-----END PGP SIGNATURE-----
Merge tag 'tty-4.20-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are some small tty fixes for 4.20-rc2
One of these missed the original 4.19-final release, I missed that I
hadn't done a pull request for it as it was in linux-next and my
branch for a long time, that's my fault.
The others are small, fixing some reported issues and finally fixing
the termios mess for alpha so that glibc has a chance to implement
some missing functionality that has been pending for many years now.
All of these have been in linux-next with no reported issues"
* tag 'tty-4.20-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: sh-sci: Fix could not remove dev_attr_rx_fifo_timeout
arch/alpha, termios: implement BOTHER, IBSHIFT and termios2
termios, tty/tty_baudrate.c: fix buffer overrun
vt: fix broken display when running aptitude
serial: sh-sci: Fix receive on SCIFA/SCIFB variants with DMA
If you run aptitude on framebuffer console, the display is corrupted. The
corruption is caused by the commit d8ae7242. The patch adds "offset" to
"start" when calling scr_memsetw, but it forgets to do the same addition
on a subsequent call to do_update_region.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: d8ae724271 ("vt: preserve unicode values corresponding to screen characters")
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Cc: stable@vger.kernel.org # 4.19
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----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=3yxi
-----END PGP SIGNATURE-----
Merge tag 'drm-next-2018-10-24' of git://anongit.freedesktop.org/drm/drm
Pull drm updates from Dave Airlie:
"This is going to rebuild more than drm as it adds a new helper to
list.h for doing bulk updates. Seemed like a reasonable addition to
me.
Otherwise the usual merge window stuff lots of i915 and amdgpu, not so
much nouveau, and piles of everything else.
Core:
- Adds a new list.h helper for doing bulk list updates for TTM.
- Don't leak fb address in smem_start to userspace (comes with EXPORT
workaround for people using mali out of tree hacks)
- udmabuf device to turn memfd regions into dma-buf
- Per-plane blend mode property
- ref/unref replacements with get/put
- fbdev conflicting framebuffers code cleaned up
- host-endian format variants
- panel orientation quirk for Acer One 10
bridge:
- TI SN65DSI86 chip support
vkms:
- GEM support.
- Cursor support
amdgpu:
- Merge amdkfd and amdgpu into one module
- CEC over DP AUX support
- Picasso APU support + VCN dynamic powergating
- Raven2 APU support
- Vega20 enablement + kfd support
- ACP powergating improvements
- ABGR/XBGR display support
- VCN jpeg support
- xGMI support
- DC i2c/aux cleanup
- Ycbcr 4:2:0 support
- GPUVM improvements
- Powerplay and powerplay endian fixes
- Display underflow fixes
vmwgfx:
- Move vmwgfx specific TTM code to vmwgfx
- Split out vmwgfx buffer/resource validation code
- Atomic operation rework
bochs:
- use more helpers
- format/byteorder improvements
qxl:
- use more helpers
i915:
- GGTT coherency getparam
- Turn off resource streamer API
- More Icelake enablement + DMC firmware
- Full PPGTT for Ivybridge, Haswell and Valleyview
- DDB distribution based on resolution
- Limited range DP display support
nouveau:
- CEC over DP AUX support
- Initial HDMI 2.0 support
virtio-gpu:
- vmap support for PRIME objects
tegra:
- Initial Tegra194 support
- DMA/IOMMU integration fixes
msm:
- a6xx perf improvements + clock prefix
- GPU preemption optimisations
- a6xx devfreq support
- cursor support
rockchip:
- PX30 support
- rgb output interface support
mediatek:
- HDMI output support on mt2701 and mt7623
rcar-du:
- Interlaced modes on Gen3
- LVDS on R8A77980
- D3 and E3 SoC support
hisilicon:
- misc fixes
mxsfb:
- runtime pm support
sun4i:
- R40 TCON support
- Allwinner A64 support
- R40 HDMI support
omapdrm:
- Driver rework changing display pipeline ordering to use common code
- DMM memory barrier and irq fixes
- Errata workarounds
exynos:
- out-bridge support for LVDS bridge driver
- Samsung 16x16 tiled format support
- Plane alpha and pixel blend mode support
tilcdc:
- suspend/resume update
mali-dp:
- misc updates"
* tag 'drm-next-2018-10-24' of git://anongit.freedesktop.org/drm/drm: (1382 commits)
firmware/dmc/icl: Add missing MODULE_FIRMWARE() for Icelake.
drm/i915/icl: Fix signal_levels
drm/i915/icl: Fix DDI/TC port clk_off bits
drm/i915/icl: create function to identify combophy port
drm/i915/gen9+: Fix initial readout for Y tiled framebuffers
drm/i915: Large page offsets for pread/pwrite
drm/i915/selftests: Disable shrinker across mmap-exhaustion
drm/i915/dp: Link train Fallback on eDP only if fallback link BW can fit panel's native mode
drm/i915: Fix intel_dp_mst_best_encoder()
drm/i915: Skip vcpi allocation for MSTB ports that are gone
drm/i915: Don't unset intel_connector->mst_port
drm/i915: Only reset seqno if actually idle
drm/i915: Use the correct crtc when sanitizing plane mapping
drm/i915: Restore vblank interrupts earlier
drm/i915: Check fb stride against plane max stride
drm/amdgpu/vcn:Fix uninitialized symbol error
drm: panel-orientation-quirks: Add quirk for Acer One 10 (S1003)
drm/amd/amdgpu: Fix debugfs error handling
drm/amdgpu: Update gc_9_0 golden settings.
drm/amd/powerplay: update PPtable with DC BTC and Tvr SocLimit fields
...
Pull tty ioctl updates from Al Viro:
"This is the compat_ioctl work related to tty ioctls.
Quite a bit of dead code taken out, all tty-related stuff gone from
fs/compat_ioctl.c. A bunch of compat bugs fixed - some still remain,
but all more or less generic tty-related ioctls should be covered
(remaining issues are in things like driver-private ioctls in a pcmcia
serial card driver not getting properly handled in 32bit processes on
64bit host, etc)"
* 'work.tty-ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (53 commits)
kill TIOCSERGSTRUCT
change semantics of ldisc ->compat_ioctl()
kill TIOCSER[SG]WILD
synclink_gt(): fix compat_ioctl()
pty: fix compat ioctls
compat_ioctl - kill keyboard ioctl handling
gigaset: add ->compat_ioctl()
vt_compat_ioctl(): clean up, use compat_ptr() properly
gigaset: don't try to printk userland buffer contents
dgnc: don't bother with (empty) stub for TCXONC
dgnc: leave TIOC[GS]SOFTCAR to ldisc
remove fallback to drivers for TIOCGICOUNT
dgnc: break-related ioctls won't reach ->ioctl()
kill the rest of tty COMPAT_IOCTL() entries
dgnc: TIOCM... won't reach ->ioctl()
isdn_tty: TCSBRK{,P} won't reach ->ioctl()
kill capinc_tty_ioctl()
take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()
synclink: reduce pointless checks in ->ioctl()
complete ->[sg]et_serial() switchover
...
Jiri Slaby