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2019-05-21tty: vt.c: Fix TIOCL_BLANKSCREEN console blanking if blankinterval == 0Yifeng Li1-2/+0
commit 75ddbc1fb11efac87b611d48e9802f6fe2bb2163 upstream. 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 a4199f5eb809 ("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: a4199f5eb809 ("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>
2019-05-16vt: always call notifier with the console lock heldNicolas Pitre1-1/+1
[ Upstream commit 7e1d226345f89ad5d0216a9092c81386c89b4983 ] 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> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
2019-01-31vt: invoke notifier on screen size changeNicolas Pitre1-0/+1
commit 0c9b1965faddad7534b6974b5b36c4ad37998f8e upstream. 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>
2018-07-08vt: prevent leaking uninitialized data to userspace via /dev/vcs*Alexander Potapenko1-2/+2
commit 21eff69aaaa0e766ca0ce445b477698dc6a9f55a upstream. KMSAN reported an infoleak when reading from /dev/vcs*: BUG: KMSAN: kernel-infoleak in vcs_read+0x18ba/0x1cc0 Call Trace: ... kmsan_copy_to_user+0x7a/0x160 mm/kmsan/kmsan.c:1253 copy_to_user ./include/linux/uaccess.h:184 vcs_read+0x18ba/0x1cc0 drivers/tty/vt/vc_screen.c:352 __vfs_read+0x1b2/0x9d0 fs/read_write.c:416 vfs_read+0x36c/0x6b0 fs/read_write.c:452 ... Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:189 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:315 __kmalloc+0x13a/0x350 mm/slub.c:3818 kmalloc ./include/linux/slab.h:517 vc_allocate+0x438/0x800 drivers/tty/vt/vt.c:787 con_install+0x8c/0x640 drivers/tty/vt/vt.c:2880 tty_driver_install_tty drivers/tty/tty_io.c:1224 tty_init_dev+0x1b5/0x1020 drivers/tty/tty_io.c:1324 tty_open_by_driver drivers/tty/tty_io.c:1959 tty_open+0x17b4/0x2ed0 drivers/tty/tty_io.c:2007 chrdev_open+0xc25/0xd90 fs/char_dev.c:417 do_dentry_open+0xccc/0x1440 fs/open.c:794 vfs_open+0x1b6/0x2f0 fs/open.c:908 ... Bytes 0-79 of 240 are uninitialized Consistently allocating |vc_screenbuf| with kzalloc() fixes the problem Reported-by: syzbot+17a8efdf800000@syzkaller.appspotmail.com Signed-off-by: Alexander Potapenko <glider@google.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-08vt: change SGR 21 to follow the standardsMike Frysinger1-1/+5
commit 65d9982d7e523a1a8e7c9af012da0d166f72fc56 upstream. ECMA-48 [1] (aka ISO 6429) has defined SGR 21 as "doubly underlined" since at least March 1984. The Linux kernel has treated it as SGR 22 "normal intensity" since it was added in Linux-0.96b in June 1992. Before that, it was simply ignored. Other terminal emulators have either ignored it, or treat it as double underline now. xterm for example added support in its 304 release (May 2014) [2] where it was previously ignoring it. Changing this behavior shouldn't be an issue: - It isn't a named capability in ncurses's terminfo database, so no script is using libtinfo/libcurses to look this up, or using tput to query & output the right sequence. - Any script assuming SGR 21 will reset intensity in all terminals already do not work correctly on non-Linux VTs (including running under screen/tmux/etc...). - If someone has written a script that only runs in the Linux VT, and they're using SGR 21 (instead of SGR 22), the output should still be readable. imo it's important to change this as the Linux VT's non-conformance is sometimes used as an argument for other terminal emulators to not implement SGR 21 at all, or do so incorrectly. [1]: https://www.ecma-international.org/publications/standards/Ecma-048.htm [2]: https://github.com/ThomasDickey/xterm-snapshots/commit/2fd29cb98d214cb536bcafbee00bc73b3f1eeb9d Signed-off-by: Mike Frysinger <vapier@chromium.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-28tty: vt: fix up tabstops properlyLinus Torvalds1-4/+4
commit f1869a890cdedb92a3fab969db5d0fd982850273 upstream. Tabs on a console with long lines do not wrap properly, so correctly account for the line length when computing the tab placement location. Reported-by: James Holderness <j4_james@hotmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09vt: fix \e[2m using the wrong placeholder color on graphical consolesAdam Borowski1-1/+1
Only vgacon and sisusbcon did it right, the rest (via generic code) tried underline (usually cyan). Signed-off-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09vt: fix unchecked __put_user() in tioclinux ioctlsAdam Borowski1-3/+3
Only read access is checked before this call. Actually, at the moment this is not an issue, as every in-tree arch does the same manual checks for VERIFY_READ vs VERIFY_WRITE, relying on the MMU to tell them apart, but this wasn't the case in the past and may happen again on some odd arch in the future. If anyone cares about 3.7 and earlier, this is a security hole (untested) on real 80386 CPUs. Signed-off-by: Adam Borowski <kilobyte@angband.pl> CC: stable@vger.kernel.org # v3.7- Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-31tty: Disable default console blanking intervalTim Gardner1-1/+1
BugLink: http://bugs.launchpad.net/bugs/869017 Console blanking is not enabling DPMS power saving (thereby negating any power-saving benefit), and is simply turning the screen content blank. This means that any crash output is invisible which is unhelpful on a server (virtual or otherwise). Furthermore, CRT burn in concerns should no longer govern the default case. Affected users could always set consoleblank on the kernel command line. Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Adam Borowski <kilobyte@angband.pl> Cc: Scot Doyle <lkml14@scotdoyle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar1-1/+1
<linux/sched/signal.h> We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/signal.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-25console: Add callback to flush scrollback buffer to consw structManuel Schölling1-0/+9
This new callback is in preparation for persistent scrollback buffer support for VGA consoles. With a single scrollback buffer for all consoles, we could flush the buffer just by invocating consw->con_switch(). But when each VGA console has its own scrollback buffer, we need a new callback to tell the video console driver which buffer to flush. Signed-off-by: Manuel Schölling <manuel.schoelling@gmx.de> Reviewed-by: Andrey Utkin <andrey_utkin@fastmail.com> Tested-by: Andrey Utkin <andrey_utkin@fastmail.com> Tested-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-13Merge branch 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds1-4/+0
Pull workqueue updates from Tejun Heo: "Mostly patches to initialize workqueue subsystem earlier and get rid of keventd_up(). The patches were headed for the last merge cycle but got delayed due to a bug found late minute, which is fixed now. Also, to help debugging, destroy_workqueue() is more chatty now on a sanity check failure." * 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: move wq_numa_init() to workqueue_init() workqueue: remove keventd_up() debugobj, workqueue: remove keventd_up() usage slab, workqueue: remove keventd_up() usage power, workqueue: remove keventd_up() usage tty, workqueue: remove keventd_up() usage mce, workqueue: remove keventd_up() usage workqueue: make workqueue available early during boot workqueue: dump workqueue state on sanity check failures in destroy_workqueue()
2016-10-30Merge 4.9-rc3 into tty-nextGreg Kroah-Hartman1-1/+6
We want the serial/tty fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27vt: clear selection before resizingScot Doyle1-0/+3
When resizing a vt its selection may exceed the new size, resulting in an invalid memory access [1]. Clear the selection before resizing. [1] http://lkml.kernel.org/r/CACT4Y+acDTwy4umEvf5ROBGiRJNrxHN4Cn5szCXE5Jw-d1B=Xw@mail.gmail.com Reported-and-tested-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Scot Doyle <lkml14@scotdoyle.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27tty: limit terminal size to 4M charsDmitry Vyukov1-0/+2
Size of kmalloc() in vc_do_resize() is controlled by user. Too large kmalloc() size triggers WARNING message on console. Put a reasonable upper bound on terminal size to prevent WARNINGs. Signed-off-by: Dmitry Vyukov <dvyukov@google.com> CC: David Rientjes <rientjes@google.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: linux-kernel@vger.kernel.org Cc: syzkaller@googlegroups.com Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27tty: vt, rename variables to sane namesJiri Slaby1-13/+13
This makes the code understandable at least. No functional changes. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27tty: vt, compute vc offsets in advanceJiri Slaby1-5/+7
Only improves readability, no functional changes. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27tty: vgacon+sisusb, move scrolldelta to a common helperJiri Slaby1-0/+38
The code is mirrorred in scrolldelta implementations of both vgacon and sisusb. Let's move the code to a separate helper where we will perform a common cleanup and further changes. While we are moving the code, make it linear and save one indentation level. This is done by returning from the "!lines" then-branch immediatelly. This allows flushing the else-branch 1 level to the left, obviously. Few more new lines and comments were added too. And do not forget to export the helper function given sisusb can be built as module. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: <linux-fbdev@vger.kernel.org> Cc: <linux-usb@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27tty: vt, unify scrolling functionsJiri Slaby1-30/+17
Both scrup and scrdown are copies of the same code except source and destination pointers computation. Unify those functions into a single one named con_scroll. Note that scrdown used step to compute the destination, while scrup did the computation explicitly. We sticked to the latter here. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27tty: vt, cleanup and document con_scrollJiri Slaby1-2/+4
Scrolling helpers scrup and scrdown both accept 'top' and 'bottom' as unsigned int. Number of lines 'nr' is accepted as int, but all callers pass down unsigned too. So change the type of 'nr' to unsigned too. Now, promote unsigned int from the helpers up to the con_scroll hook which actually accepted all those as signed int. Next, the 'dir' parameter can have only two values and we define constants for that: SM_UP and SM_DOWN. Switch them to enum and do proper type checking on 'dir' too. Finally, document the behaviour of the hook. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: <linux-fbdev@vger.kernel.org> Cc: <linux-usb@vger.kernel.org> Cc: <linux-parisc@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27tty: vt, fix bogus division in csi_JJiri Slaby1-1/+1
In csi_J(3), the third parameter of scr_memsetw (vc_screenbuf_size) is divided by 2 inappropriatelly. But scr_memsetw expects size, not count, because it divides the size by 2 on its own before doing actual memset-by-words. So remove the bogus division. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Petr Písař <ppisar@redhat.com> Fixes: f8df13e0a9 (tty: Clean console safely) Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-19Merge branch 'for-4.9' into for-4.10Tejun Heo1-4/+0
2016-10-10Merge branch 'printk-cleanups'Linus Torvalds1-3/+3
Merge my system logging cleanups, triggered by the broken '\n' patches. The line continuation handling has been broken basically forever, and the code to handle the system log records was both confusing and dubious. And it would do entirely the wrong thing unless you always had a terminating newline, partly because it couldn't actually see whether a message was marked KERN_CONT or not (but partly because the LOG_CONT handling in the recording code was rather confusing too). This re-introduces a real semantically meaningful KERN_CONT, and fixes the few places I noticed where it was missing. There are probably more missing cases, since KERN_CONT hasn't actually had any semantic meaning for at least four years (other than the checkpatch meaning of "no log level necessary, this is a continuation line"). This also allows the combination of KERN_CONT and a log level. In that case the log level will be ignored if the merging with a previous line is successful, but if a new record is needed, that new record will now get the right log level. That also means that you can at least in theory combine KERN_CONT with the "pr_info()" style helpers, although any use of pr_fmt() prefixing would make that just result in a mess, of course (the prefix would end up in the middle of a continuing line). * printk-cleanups: printk: make reading the kernel log flush pending lines printk: re-organize log_output() to be more legible printk: split out core logging code into helper function printk: reinstate KERN_CONT for printing continuation lines
2016-10-09printk: reinstate KERN_CONT for printing continuation linesLinus Torvalds1-3/+3
Long long ago the kernel log buffer was a buffered stream of bytes, very much like stdio in user space. It supported log levels by scanning the stream and noticing the log level markers at the beginning of each line, but if you wanted to print a partial line in multiple chunks, you just did multiple printk() calls, and it just automatically worked. Except when it didn't, and you had very confusing output when different lines got all mixed up with each other. Then you got fragment lines mixing with each other, or with non-fragment lines, because it was traditionally impossible to tell whether a printk() call was a continuation or not. To at least help clarify the issue of continuation lines, we added a KERN_CONT marker back in 2007 to mark continuation lines: 474925277671 ("printk: add KERN_CONT annotation"). That continuation marker was initially an empty string, and didn't actuall make any semantic difference. But it at least made it possible to annotate the source code, and have check-patch notice that a printk() didn't need or want a log level marker, because it was a continuation of a previous line. To avoid the ambiguity between a continuation line that had that KERN_CONT marker, and a printk with no level information at all, we then in 2009 made KERN_CONT be a real log level marker which meant that we could now reliably tell the difference between the two cases. 5fd29d6ccbc9 ("printk: clean up handling of log-levels and newlines") and we could take advantage of that to make sure we didn't mix up continuation lines with lines that just didn't have any loglevel at all. Then, in 2012, the kernel log buffer was changed to be a "record" based log, where each line was a record that has a loglevel and a timestamp. You can see the beginning of that conversion in commits e11fea92e13f ("kmsg: export printk records to the /dev/kmsg interface") 7ff9554bb578 ("printk: convert byte-buffer to variable-length record buffer") with a number of follow-up commits to fix some painful fallout from that conversion. Over all, it took a couple of months to sort out most of it. But the upside was that you could have concurrent readers (and writers) of the kernel log and not have lines with mixed output in them. And one particular pain-point for the record-based kernel logging was exactly the fragmentary lines that are generated in smaller chunks. In order to still log them as one recrod, the continuation lines need to be attached to the previous record properly. However the explicit continuation record marker that is actually useful for this exact case was actually removed in aroundm the same time by commit 61e99ab8e35a ("printk: remove the now unnecessary "C" annotation for KERN_CONT") due to the incorrect belief that KERN_CONT wasn't meaningful. The ambiguity between "is this a continuation line" or "is this a plain printk with no log level information" was reintroduced, and in fact became an even bigger pain point because there was now the whole record-level merging of kernel messages going on. This patch reinstates the KERN_CONT as a real non-empty string marker, so that the ambiguity is fixed once again. But it's not a plain revert of that original removal: in the four years since we made KERN_CONT an empty string again, not only has the format of the log level markers changed, we've also had some usage changes in this area. For example, some ACPI code seems to use KERN_CONT _together_ with a log level, and now uses both the KERN_CONT marker and (for example) a KERN_INFO marker to show that it's an informational continuation of a line. Which is actually not a bad idea - if the continuation line cannot be attached to its predecessor, without the log level information we don't know what log level to assign to it (and we traditionally just assigned it the default loglevel). So having both a log level and the KERN_CONT marker is not necessarily a bad idea, but it does mean that we need to actually iterate over potentially multiple markers, rather than just a single one. Also, since KERN_CONT was still conceptually needed, and encouraged, but didn't actually _do_ anything, we've also had the reverse problem: rather than having too many annotations it has too few, and there is bit rot with code that no longer marks the continuation lines with the KERN_CONT marker. So this patch not only re-instates the non-empty KERN_CONT marker, it also fixes up the cases of bit-rot I noticed in my own logs. There are probably other cases where KERN_CONT will be needed to be added, either because it is new code that never dealt with the need for KERN_CONT, or old code that has bitrotted without anybody noticing. That said, we should strive to avoid the need for KERN_CONT. It does result in real problems for logging, and should generally not be seen as a good feature. If we some day can get rid of the feature entirely, because nobody does any fragmented printk calls, that would be lovely. But until that point, let's at mark the code that relies on the hacky multi-fragment kernel printk's. Not only does it avoid the ambiguity, it also annotates code as "maybe this would be good to fix some day". (That said, particularly during single-threaded bootup, the downsides of KERN_CONT are very limited. Things get much hairier when you have multiple threads going on and user level reading and writing logs too). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-22vt: Emulate \e[100-107m (bright background colors).Adam Borowski1-2/+3
For now, these fall back to regular (dark) colors. It'd be tempting to replace blink with bright backgrounds, as permitted by CGA/VGA -- we already muck with the other programmable bit (foreground brightness vs 512 character font). This would bring vgacon in line with fbcon, which doesn't support blink anywhere but on some drivers renders that bit as bright background. If that is done, this commit should be amended to be one of ways of setting that bit. Signed-off-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22vt: Support \e[90-97m (bright foreground colors).Adam Borowski1-0/+4
These codes are supported by all major terminals, thus they occasionally see some use despite being redundant with \e[38;5;(x+8)m or (less exactly) \e[1;3(x)m. Signed-off-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22vt: Drop a no longer true comment.Adam Borowski1-2/+2
Some guy went on a patching spree, adding 24-bit colour support all around: https://gist.github.com/XVilka/8346728 Signed-off-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22vt: Make a comparison <= for readability.Adam Borowski1-1/+1
All other uses of vc_npar are inclusive (save for < NPAR) which raises eyebrows, so let's at least do so consistently. Signed-off-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22vt: Fix a read-past-array in vc_t416_color().Adam Borowski1-1/+1
This makes it show up on UBSAN: perl -e 'for (0..15) {my @x=("0")x$_;push @x,qw(38 2 64 128 192 4);printf "\e[%smAfter %d zeroes.\e[0m\n", join(";",@x[0..($_+5<15?$_+5:15)]), $_}' Seems harmless: if you can programmatically read attributes of a vt character (/dev/vcsa*), multiple probes can obtain parts of vt_mode then lowest byte (5th on 64-bit big-endian) of a pointer. Signed-off-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-17tty, workqueue: remove keventd_up() usageTejun Heo1-4/+0
Now that workqueue can handle work item queueing from very early during boot, there is no need to delay schedule_work() while !keventd_up(). Remove it. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@linux.intel.com>
2016-07-04Merge 4.7-rc6 into tty-nextGreg Kroah-Hartman1-0/+1
We want the tty/serial fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt: Fix soft lockup in fbcon cursor blink timer.David Daney1-0/+1
We are getting somewhat random soft lockups with this signature: [ 86.992215] [<fffffc00080935e0>] el1_irq+0xa0/0x10c [ 86.997082] [<fffffc000841822c>] cursor_timer_handler+0x30/0x54 [ 87.002991] [<fffffc000810ec44>] call_timer_fn+0x54/0x1a8 [ 87.008378] [<fffffc000810ef88>] run_timer_softirq+0x1c4/0x2bc [ 87.014200] [<fffffc000809077c>] __do_softirq+0x114/0x344 [ 87.019590] [<fffffc00080af45c>] irq_exit+0x74/0x98 [ 87.024458] [<fffffc00080fac20>] __handle_domain_irq+0x98/0xfc [ 87.030278] [<fffffc000809056c>] gic_handle_irq+0x94/0x190 This is caused by the vt visual_init() function calling into fbcon_init() with a vc_cur_blink_ms value of zero. This is a transient condition, as it is later set to a non-zero value. But, if the timer happens to expire while the blink rate is zero, it goes into an endless loop, and we get soft lockup. The fix is to initialize vc_cur_blink_ms before calling the con_init() function. Signed-off-by: David Daney <david.daney@cavium.com> Cc: stable@vger.kernel.org Acked-by: Pavel Machek <pavel@ucw.cz> Tested-by: Ming Lei <ming.lei@canonical.com> Acked-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, remove unused vc_deccolmJiri Slaby1-1/+0
vc_deccolm is only set and never read, remove the member from vc_data. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, convert more macros to functionsJiri Slaby1-28/+34
Namely convert: * IS_FG -> con_is_fg * DO_UPDATE -> con_should_update * CON_IS_VISIBLE -> con_is_visible DO_UPDATE was a weird name for a yes/no answer, so the new name is con_should_update. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: linux-usb@vger.kernel.org Cc: linux-fbdev@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, whitespace cleanup in csi_mJiri Slaby1-84/+85
Flush the switch cases to be aligned with the switch. Mostly everything can now fit to the 80-chars terminal. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, too many commands per line in rgb_foregroundJiri Slaby1-11/+16
Do not opencode max3, use the macro. Separate commands. Until now, I have not noticed the comma. Make it one line, one command. And make the code obvious. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, do not pass structure over stackJiri Slaby1-33/+33
The compiler noticed passing structure over stack. Even though rgb is a small structure, let us define one and pass that over all the functions wherever needed. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, separate T.416 high colors handlerJiri Slaby1-48/+37
The code with T.416 high colors handling is flushed to the right and hard to read. Move the code to a separate function and remove code duplication for foreground & background colors. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, get rid of ugly FLUSH macroJiri Slaby1-13/+18
It's a macro accessing and changing some local variables. And the code uses it without appending semicolon which confuses everybody too. Switch from this bad guy to a sane standard function. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, drop VT_BUF_VRAM_ONLYJiri Slaby1-19/+3
It is never defined. And I spent quite some time looking into the history and cannot find how this was ever used. Given it was not used in the history, I doubt it currently works as expected after the years of changes all over the code. So kill it. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, consw->con_set_palette cleanupJiri Slaby1-1/+1
* allow NULL consw->con_set_palette (some consoles define an empty hook) * => remove empty hooks now * return value of consw->con_set_palette is never checked => make the function void * document consw->con_set_palette a bit Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: linux-usb@vger.kernel.org Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: linux-fbdev@vger.kernel.org Cc: linux-parisc@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: vt, consw->con_scrolldelta cleanupJiri Slaby1-1/+1
* allow NULL consw->con_scrolldelta (some consoles define an empty hook) * => remove empty hooks now * return value of consw->con_scrolldelta is never checked => make the function void * document consw->con_scrolldelta a bit Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: linux-usb@vger.kernel.org Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: linux-fbdev@vger.kernel.org Cc: linux-parisc@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25vt: remove lines parameter from scrollbackJiri Slaby1-4/+2
It is always called with 0, so remove the parameter and pass the default down to scrolldelta without checking. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-04tty: vt, finish looping on duplicateJiri Slaby1-5/+4
When the console is already registered, stop crawling the registered_con_driver array and return an error immediatelly. This makes the code more obvious. And we do not need to initialize retval anymore. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-04tty: vt, return error when con_startup failsJiri Slaby1-2/+3
When csw->con_startup() fails in do_register_con_driver, we return no error (i.e. 0). This was changed back in 2006 by commit 3e795de763. Before that we used to return -ENODEV. So fix the return value to be -ENODEV in that case again. Fixes: 3e795de763 ("VT binding: Add binding/unbinding support for the VT console") Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: "Dan Carpenter" <dan.carpenter@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30tty: vt, use proper type for default colorsJiri Slaby1-10/+17
Every user of default_red, default_grn, and default_blu treats them as unsigned char. So make it really unsigned char. And indent the initializers and module_param properly. This saves ~ 100 bytes of data. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30tty: vt, make color_table constJiri Slaby1-1/+1
This means all ->con_set_palette have to have the second parameter const too now. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30tty: vt, get rid of weird source code flowJiri Slaby1-31/+39
Some code in vc_allocate is indented by 4 spaces. It is inside a condition. Invert the condition and move the code to the first indentation level (using \tab). And insert some empty lines to have logical code blocks separated. Then, instead of freeing in an 'if' false branch, use goto-error label as fail path. Maybe better to look at this patch with diff -w -b. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30tty: vt, remove reduntant checkJiri Slaby1-4/+0
MAX_NR_CONSOLES and MAX_NR_USER_CONSOLES are both 63 since they were introduced in 1.1.54. And since vc_allocate does: if (currcons >= MAX_NR_CONSOLES) return -ENXIO; if (!vc_cons[currcons].d) { if (currcons >= MAX_NR_USER_CONSOLES && !capable(CAP_SYS_RESOURCE)) return -EPERM; } the second check is pointless. Remove both the check and the macro MAX_NR_USER_CONSOLES. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: Fugang Duan <fugang.duan@nxp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07tty: vt: initialize softcursor_original correctlyMelchior FRANZ1-1/+1
add_softcursor() stores the contents of the text buffer position in this variable before drawing the softcursor, whereas hide_softcursor() writes the value back. A value of -1 means that no cursor has been drawn and therefore no character is to be restored. softcursor_original, however, is only implicitly initialized with 0. Therefore, when hide_softcursor is called for the first time (console_init -> con_init -> redraw_screen -> hide_cursor), it wrongly writes 0x0000 in the top left corner of the text buffer. Normally, this is just as black as the rest of the screen (vc_video_erase_char) and can't be seen, but it appears as a black cursor rectangle on non-black backgrounds e.g. with boot option "vt.global_cursor_default=0 vt.color=0xf0". softcursor_original needs to be initialized with -1. Signed-off-by: Melchior FRANZ <mfranz@aon.at> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>