Commit Graph

61 Commits

Author SHA1 Message Date
Ahmed S. Darwish 151db8c08c vt_ioctl: Remove in_interrupt() check
reset_vc() uses a "!in_interrupt()" conditional before resetting the
palettes, which is a blocking operation. Since commit
   8b6312f4dc ("[PATCH] vt: refactor console SAK processing")

all calls are invoked from a workqueue process context, with the
blocking console lock always acquired.

Remove the "!in_interrupt()" check.

Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20210208181615.381861-2-bigeasy@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-09 11:45:04 +01:00
Jiri Slaby ff2047fb75 vt: drop old FONT ioctls
Drop support for these ioctls:
* PIO_FONT, PIO_FONTX
* GIO_FONT, GIO_FONTX
* PIO_FONTRESET

As was demonstrated by commit 90bfdeef83 (tty: make FONTX ioctl use
the tty pointer they were actually passed), these ioctls are not used
from userspace, as:
1) they used to be broken (set up font on current console, not the open
   one) and racy (before the commit above)
2) KDFONTOP ioctl is used for years instead

Note that PIO_FONTRESET is defunct on most systems as VGA_CONSOLE is set
on them for ages. That turns on BROKEN_GRAPHICS_PROGRAMS which makes
PIO_FONTRESET just return an error.

We are removing KD_FONT_FLAG_OLD here as it was used only by these
removed ioctls. kd.h header exists both in kernel and uapi headers, so
we can remove the kernel one completely. Everyone includeing kd.h will
now automatically get the uapi one.

There are now unused definitions of the ioctl numbers and "struct
consolefontdesc" in kd.h, but as it is a uapi header, I am not touching
these.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210105120239.28031-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07 16:17:31 +01:00
Yan.Gao fa26b3263f tty: Fix whitespace inconsistencies in vt_io_ioctl
Replaces spaces with tabs for indentation.

Signed-off-by: Yan.Gao <gao.yanB@h3c.com>
Link: https://lore.kernel.org/r/20201209030551.48029-1-gao.yanB@h3c.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09 15:35:43 +01:00
Linus Torvalds 90bfdeef83 tty: make FONTX ioctl use the tty pointer they were actually passed
Some of the font tty ioctl's always used the current foreground VC for
their operations.  Don't do that then.

This fixes a data race on fg_console.

Side note: both Michael Ellerman and Jiri Slaby point out that all these
ioctls are deprecated, and should probably have been removed long ago,
and everything seems to be using the KDFONTOP ioctl instead.

In fact, Michael points out that it looks like busybox's loadfont
program seems to have switched over to using KDFONTOP exactly _because_
of this bug (ahem.. 12 years ago ;-).

Reported-by: Minh Yuan <yuanmingbuaa@gmail.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-11-02 14:49:17 -08:00
Jiri Slaby d546547903 vt_ioctl: fix GIO_UNIMAP regression
In commit 5ba1278787, we shuffled with the check of 'perm'. But my
brain somehow inverted the condition in 'do_unimap_ioctl' (I thought
it is ||, not &&), so GIO_UNIMAP stopped working completely.

Move the 'perm' checks back to do_unimap_ioctl and do them right again.
In fact, this reverts this part of code to the pre-5ba127878722 state.
Except 'perm' is now a bool.

Fixes: 5ba1278787 ("vt_ioctl: move perm checks level up")
Cc: stable@vger.kernel.org
Reported-by: Fabian Vogt <fvogt@suse.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20201026055419.30518-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-28 13:41:17 +01:00
Tetsuo Handa 988d076336 vt_ioctl: make VT_RESIZEX behave like VT_RESIZE
syzbot is reporting UAF/OOB read at bit_putcs()/soft_cursor() [1][2], for
vt_resizex() from ioctl(VT_RESIZEX) allows setting font height larger than
actual font height calculated by con_font_set() from ioctl(PIO_FONT).
Since fbcon_set_font() from con_font_set() allocates minimal amount of
memory based on actual font height calculated by con_font_set(),
use of vt_resizex() can cause UAF/OOB read for font data.

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

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

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

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

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

Reported-by: syzbot <syzbot+b308f5fd049fbbc6e74f@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+16469b5e8e5a72e9131e@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/4933b81b-9b1a-355b-df0e-9b31e8280ab9@i-love.sakura.ne.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-27 14:17:43 +02:00
Greg Kroah-Hartman 8f49a2fe8e Linux 5.9-rc3
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl9ML+IeHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGA8EIAIy/kTbFS0yrE9yV
 hb98oX0z9+EU9YQg9vhaRWwPd+rJF/JMQZLqYcwbhjG9abaUL3T3fEcSAefMHw8E
 LAt+hYzA38dHt7tqhsFQX3vV1VorvDVICBVN0yRPRWKKikq4OPIHzaAR9tleGAF5
 8btQisl1PjN+obwYmLuNb6aX16OCwAF+uXOwehcoJs9dvMNhwtXRzfOflWzOvOo6
 tE0bHErlylLDfLv4ZzEfczTdks4QJZ7C0xLSf3oN9AAynW42Xnhct4hi8qZY/hCf
 CMaqeN4hdpub6TvQIqBdDqMMjEXGFgeNSnAEBQY9VpvUqz8NTu6sQxwgJEKDF5tg
 d81lv2c=
 =uW/F
 -----END PGP SIGNATURE-----

Merge 5.9-rc3 into tty-next

We need the tty/serial fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-31 07:19:25 +02:00
Jiri Slaby ea239f1e32 tty: vt, fix kernel-doc
As in the previous patches, fix kernel-doc in vt.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085655.12071-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-18 13:51:18 +02:00
George Kennedy bc5269ca76 vt_ioctl: change VT_RESIZEX ioctl to check for error return from vc_resize()
vc_resize() can return with an error after failure. Change VT_RESIZEX ioctl
to save struct vc_data values that are modified and restore the original
values in case of error.

Signed-off-by: George Kennedy <george.kennedy@oracle.com>
Cc: stable <stable@vger.kernel.org>
Reported-by: syzbot+38a3699c7eaf165b97a6@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/1596213192-6635-2-git-send-email-george.kennedy@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-18 13:22:56 +02:00
Jiri Slaby 5ba1278787 vt_ioctl: move perm checks level up
Synchronize with others and check perm directly in vt_k_ioctl.
We do not need to pass perm to do_fontx_ioctl and do_unimap_ioctl then.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-38-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24 17:08:35 +02:00
Jiri Slaby a4c53c830b vt_ioctl: move vt_kdsetmode out of vt_k_ioctl
It's too long to be inlined.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-37-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24 17:08:34 +02:00
Jiri Slaby 7a0ac4b17f vt_ioctl: move vt_io_fontreset out of vt_io_ioctl
This also eliminates the ifdeffery by using if and __is_defined.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-36-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24 17:08:34 +02:00
Jiri Slaby 5422337d56 vt_ioctl: move vt_resizex out of vt_ioctl
It's too long to be inlined.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-35-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24 17:08:34 +02:00
Jiri Slaby 535082d907 vt_ioctl: move vt_reldisp out of vt_ioctl
It's too long to be inlined.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-34-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24 17:08:34 +02:00
Jiri Slaby ebf1efbb1a vt_ioctl: move vt_setactivate out of vt_ioctl
It's too long to be inlined.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-33-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24 17:08:34 +02:00
Jiri Slaby bfbbdfa4de vt_ioctl: move io ioctls to a separate function
We create a new vt_io_ioctl here and move there all the IO ioctls.  This
makes vt_ioctl significantly smaller.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-32-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24 17:08:34 +02:00
Jiri Slaby 832a62ab6b vt_ioctl: move K* ioctls to a separate function
We create a new vt_k_ioctl here and move there all the K* ioctls.  This
makes vt_ioctl significantly smaller.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-31-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24 17:08:34 +02:00
Jiri Slaby eca734d8f0 vt_ioctl: eliminate use of uival and ucval
They were used for the first parameter of put_user. But put_user accepts
constants in the parameter and also determines the type only by the
second parameter. So we can safely drop these helpers and simplify the
code a bit.

Including the removal of set_int label.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-30-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24 17:08:34 +02:00
Jiri Slaby 0ce8179e24 vt_ioctl: eliminate ret & breaks in vt_ioctl
This is still a leftover from BKL, when we locked it around vt_ioctl's
code. We can return instead of breaks in the switch loop. And we can
return in case of errors too. This allows for sifting of the code to the
left in some cases.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-29-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24 17:08:34 +02:00
Eric Biggers 7cf64b18b0 vt: vt_ioctl: fix use-after-free in vt_in_use()
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>
2020-03-27 12:35:04 +01:00
Eric Biggers ca4463bf84 vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console
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>
2020-03-27 12:35:04 +01:00
Eric Biggers 1aa6e058dd vt: vt_ioctl: remove unnecessary console allocation checks
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>
2020-03-12 21:43:49 +01:00
Jiri Slaby f400991bf8 vt: switch vt_dont_switch to bool
vt_dont_switch is pure boolean, no need for whole char.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 08:35:39 +01:00
Greg Kroah-Hartman ba08cf452f Merge 5.6-rc3 into tty-next
We want the tty fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-24 08:39:55 +01:00
Jiri Slaby e587e8f174 vt: ioctl, switch VT_IS_IN_USE and VT_BUSY to inlines
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>
2020-02-21 10:31:18 +01:00
Jiri Slaby dce05aa6ee vt: selection, introduce vc_is_sel
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>
2020-02-21 10:31:18 +01:00
Eric Dumazet 6cd1ed50ef vt: vt_ioctl: fix race in VT_RESIZEX
We need to make sure vc_cons[i].d is not NULL after grabbing
console_lock(), or risk a crash.

general protection fault, probably for non-canonical address 0xdffffc0000000068: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000340-0x0000000000000347]
CPU: 1 PID: 19462 Comm: syz-executor.5 Not tainted 5.5.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:vt_ioctl+0x1f96/0x26d0 drivers/tty/vt/vt_ioctl.c:883
Code: 74 41 e8 bd a6 84 fd 48 89 d8 48 c1 e8 03 42 80 3c 28 00 0f 85 e4 04 00 00 48 8b 03 48 8d b8 40 03 00 00 48 89 fa 48 c1 ea 03 <42> 0f b6 14 2a 84 d2 74 09 80 fa 03 0f 8e b1 05 00 00 44 89 b8 40
RSP: 0018:ffffc900086d7bb0 EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffffffff8c34ee88 RCX: ffffc9001415c000
RDX: 0000000000000068 RSI: ffffffff83f0e6e3 RDI: 0000000000000340
RBP: ffffc900086d7cd0 R08: ffff888054ce0100 R09: fffffbfff16a2f6d
R10: ffff888054ce0998 R11: ffff888054ce0100 R12: 000000000000001d
R13: dffffc0000000000 R14: 1ffff920010daf79 R15: 000000000000ff7f
FS:  00007f7d13c12700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd477e3c38 CR3: 0000000095d0a000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tty_ioctl+0xa37/0x14f0 drivers/tty/tty_io.c:2660
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x123/0x180 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45b399
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f7d13c11c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7d13c126d4 RCX: 000000000045b399
RDX: 0000000020000080 RSI: 000000000000560a RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000666 R14: 00000000004c7f04 R15: 000000000075bf2c
Modules linked in:
---[ end trace 80970faf7a67eb77 ]---
RIP: 0010:vt_ioctl+0x1f96/0x26d0 drivers/tty/vt/vt_ioctl.c:883
Code: 74 41 e8 bd a6 84 fd 48 89 d8 48 c1 e8 03 42 80 3c 28 00 0f 85 e4 04 00 00 48 8b 03 48 8d b8 40 03 00 00 48 89 fa 48 c1 ea 03 <42> 0f b6 14 2a 84 d2 74 09 80 fa 03 0f 8e b1 05 00 00 44 89 b8 40
RSP: 0018:ffffc900086d7bb0 EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffffffff8c34ee88 RCX: ffffc9001415c000
RDX: 0000000000000068 RSI: ffffffff83f0e6e3 RDI: 0000000000000340
RBP: ffffc900086d7cd0 R08: ffff888054ce0100 R09: fffffbfff16a2f6d
R10: ffff888054ce0998 R11: ffff888054ce0100 R12: 000000000000001d
R13: dffffc0000000000 R14: 1ffff920010daf79 R15: 000000000000ff7f
FS:  00007f7d13c12700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd477e3c38 CR3: 0000000095d0a000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: stable <stable@vger.kernel.org>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20200210190721.200418-1-edumazet@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-12 11:53:23 -08:00
Linus Torvalds 44adbac8f7 Merge branch 'work.tty-ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
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
  ...
2018-10-24 14:43:41 +01:00
Al Viro 9d1807daef vt_compat_ioctl(): clean up, use compat_ptr() properly
we need it for "convert the structure" cases too

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-10-13 00:50:50 -04:00
Gustavo A. R. Silva e97267cb4d tty: vt_ioctl: fix potential Spectre v1
vsa.console is indirectly controlled by user-space, hence leading to
a potential exploitation of the Spectre variant 1 vulnerability.

This issue was detected with the help of Smatch:

drivers/tty/vt/vt_ioctl.c:711 vt_ioctl() warn: potential spectre issue
'vc_cons' [r]

Fix this by sanitizing vsa.console before using it to index vc_cons

Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].

[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2

Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18 15:51:30 +02:00
Dominik Brodowski 66f4e88cc6 x86/ioport: add ksys_ioperm() helper; remove in-kernel calls to sys_ioperm()
Using this helper allows us to avoid the in-kernel calls to the
sys_ioperm() syscall. The ksys_ prefix denotes that this function is meant
as a drop-in replacement for the syscall. In particular, it uses the same
calling convention as sys_ioperm().

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: x86@kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02 20:16:12 +02:00
Linus Torvalds 93f30c73ec Merge branch 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull compat and uaccess updates from Al Viro:

 - {get,put}_compat_sigset() series

 - assorted compat ioctl stuff

 - more set_fs() elimination

 - a few more timespec64 conversions

 - several removals of pointless access_ok() in places where it was
   followed only by non-__ variants of primitives

* 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (24 commits)
  coredump: call do_unlinkat directly instead of sys_unlink
  fs: expose do_unlinkat for built-in callers
  ext4: take handling of EXT4_IOC_GROUP_ADD into a helper, get rid of set_fs()
  ipmi: get rid of pointless access_ok()
  pi433: sanitize ioctl
  cxlflash: get rid of pointless access_ok()
  mtdchar: get rid of pointless access_ok()
  r128: switch compat ioctls to drm_ioctl_kernel()
  selection: get rid of field-by-field copyin
  VT_RESIZEX: get rid of field-by-field copyin
  i2c compat ioctls: move to ->compat_ioctl()
  sched_rr_get_interval(): move compat to native, get rid of set_fs()
  mips: switch to {get,put}_compat_sigset()
  sparc: switch to {get,put}_compat_sigset()
  s390: switch to {get,put}_compat_sigset()
  ppc: switch to {get,put}_compat_sigset()
  parisc: switch to {get,put}_compat_sigset()
  get_compat_sigset()
  get rid of {get,put}_compat_itimerspec()
  io_getevents: Use timespec64 to represent timeouts
  ...
2017-11-17 11:54:55 -08:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Al Viro 1b3bce4d6b VT_RESIZEX: get rid of field-by-field copyin
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-29 12:36:26 -04:00
Adam Borowski f8564c93e0 vt: drop access_ok() calls in unimap ioctls
Done by copy_{from,to}_user().

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09 11:07:36 +02:00
Ingo Molnar 3f07c01441 sched/headers: Prepare for new header dependencies before moving code to <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>
2017-03-02 08:42:29 +01:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Jiri Slaby f8b0c2e688 tty: vt, ignore PIO_UNIMAPCLR param
We do not do hashtables for unicode fonts since 1995 (1.3.28). So it
is time to remove the second parameter of con_clear_unimap and ignore
the advice from userspace completely.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25 09:04:48 -07:00
Nicholas Mc Guire 4c0d9b17d1 vt: vt_ioctl: use msecs_to_jiffies for time conversion
Converting milliseconds to jiffies by "val * HZ / 1000" is technically
OK but msecs_to_jiffies(val) is the cleaner solution and handles all
corner cases correctly. This is a minor API consolidation only and
should make things more readable.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-07 04:02:26 +01:00
Ross Lagerwall ef223fb3d1 tty/vt: Return EBUSY if deallocating VT1 and it is busy
Commit 421b40a628 ("tty/vt: Fix vc_deallocate() lock order") changed
the behavior when deallocating VT 1.  Previously if trying to
deallocate VT1 and it is busy, we would return EBUSY.  The commit
changed this to return 0 (success).

This commit restores the old behavior.

Signed-off-by: Ross Lagerwall <rosslagerwall@gmail.com>
Tested-by: Mikael Pettersson <mikpe@it.uu.se>
Acked-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-17 12:37:29 -07:00
Peter Hurley 421b40a628 tty/vt: Fix vc_deallocate() lock order
Now that the tty port owns the flip buffers and i/o is allowed
from the driver even when no tty is attached, the destruction
of the tty port (and the flip buffers) must ensure that no
outstanding work is pending.

Unfortunately, this creates a lock order problem with the
console_lock (see attached lockdep report [1] below).

For single console deallocation, drop the console_lock prior
to port destruction. When multiple console deallocation,
defer port destruction until the consoles have been
deallocated.

tty_port_destroy() is not required if the port has not
been used; remove from vc_allocate() failure path.

[1] lockdep report from Dave Jones <davej@redhat.com>

 ======================================================
 [ INFO: possible circular locking dependency detected ]
 3.9.0+ #16 Not tainted
 -------------------------------------------------------
 (agetty)/26163 is trying to acquire lock:
 blocked:  ((&buf->work)){+.+...}, instance: ffff88011c8b0020, at: [<ffffffff81062065>] flush_work+0x5/0x2e0

 but task is already holding lock:
 blocked:  (console_lock){+.+.+.}, instance: ffffffff81c2fde0, at: [<ffffffff813bc201>] vt_ioctl+0xb61/0x1230

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (console_lock){+.+.+.}:
        [<ffffffff810b3f74>] lock_acquire+0xa4/0x210
        [<ffffffff810416c7>] console_lock+0x77/0x80
        [<ffffffff813c3dcd>] con_flush_chars+0x2d/0x50
        [<ffffffff813b32b2>] n_tty_receive_buf+0x122/0x14d0
        [<ffffffff813b7709>] flush_to_ldisc+0x119/0x170
        [<ffffffff81064381>] process_one_work+0x211/0x700
        [<ffffffff8106498b>] worker_thread+0x11b/0x3a0
        [<ffffffff8106ce5d>] kthread+0xed/0x100
        [<ffffffff81601cac>] ret_from_fork+0x7c/0xb0

 -> #0 ((&buf->work)){+.+...}:
        [<ffffffff810b349a>] __lock_acquire+0x193a/0x1c00
        [<ffffffff810b3f74>] lock_acquire+0xa4/0x210
        [<ffffffff810620ae>] flush_work+0x4e/0x2e0
        [<ffffffff81065305>] __cancel_work_timer+0x95/0x130
        [<ffffffff810653b0>] cancel_work_sync+0x10/0x20
        [<ffffffff813b8212>] tty_port_destroy+0x12/0x20
        [<ffffffff813c65e8>] vc_deallocate+0xf8/0x110
        [<ffffffff813bc20c>] vt_ioctl+0xb6c/0x1230
        [<ffffffff813b01a5>] tty_ioctl+0x285/0xd50
        [<ffffffff811ba825>] do_vfs_ioctl+0x305/0x530
        [<ffffffff811baad1>] sys_ioctl+0x81/0xa0
        [<ffffffff81601d59>] system_call_fastpath+0x16/0x1b

 other info that might help us debug this:

 [ 6760.076175]  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(console_lock);
                                lock((&buf->work));
                                lock(console_lock);
   lock((&buf->work));

  *** DEADLOCK ***

 1 lock on stack by (agetty)/26163:
  #0: blocked:  (console_lock){+.+.+.}, instance: ffffffff81c2fde0, at: [<ffffffff813bc201>] vt_ioctl+0xb61/0x1230
 stack backtrace:
 Pid: 26163, comm: (agetty) Not tainted 3.9.0+ #16
 Call Trace:
  [<ffffffff815edb14>] print_circular_bug+0x200/0x20e
  [<ffffffff810b349a>] __lock_acquire+0x193a/0x1c00
  [<ffffffff8100a269>] ? sched_clock+0x9/0x10
  [<ffffffff8100a269>] ? sched_clock+0x9/0x10
  [<ffffffff8100a200>] ? native_sched_clock+0x20/0x80
  [<ffffffff810b3f74>] lock_acquire+0xa4/0x210
  [<ffffffff81062065>] ? flush_work+0x5/0x2e0
  [<ffffffff810620ae>] flush_work+0x4e/0x2e0
  [<ffffffff81062065>] ? flush_work+0x5/0x2e0
  [<ffffffff810b15db>] ? mark_held_locks+0xbb/0x140
  [<ffffffff8113c8a3>] ? __free_pages_ok.part.57+0x93/0xc0
  [<ffffffff810b15db>] ? mark_held_locks+0xbb/0x140
  [<ffffffff810652f2>] ? __cancel_work_timer+0x82/0x130
  [<ffffffff81065305>] __cancel_work_timer+0x95/0x130
  [<ffffffff810653b0>] cancel_work_sync+0x10/0x20
  [<ffffffff813b8212>] tty_port_destroy+0x12/0x20
  [<ffffffff813c65e8>] vc_deallocate+0xf8/0x110
  [<ffffffff813bc20c>] vt_ioctl+0xb6c/0x1230
  [<ffffffff810aec41>] ? lock_release_holdtime.part.30+0xa1/0x170
  [<ffffffff813b01a5>] tty_ioctl+0x285/0xd50
  [<ffffffff812b00f6>] ? inode_has_perm.isra.46.constprop.61+0x56/0x80
  [<ffffffff811ba825>] do_vfs_ioctl+0x305/0x530
  [<ffffffff812b04db>] ? selinux_file_ioctl+0x5b/0x110
  [<ffffffff811baad1>] sys_ioctl+0x81/0xa0
  [<ffffffff81601d59>] system_call_fastpath+0x16/0x1b

Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 12:15:59 -07:00
Josh Triplett a5e04b760a drivers/tty/vt/vt_ioctl.c: Include <linux/suspend.h> for pm_set_vt_switch
C files should include the header files that prototype their functions.
This keeps the types in sync, and eliminates warnings from GCC
(-Wmissing-prototypes) and Sparse (-Wdecl).

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-21 15:19:52 -08:00
Rabin Vincent a7b12929be vt: fix race in vt_waitactive()
pm_restore_console() is called from the suspend/resume path, and this
calls vt_move_to_console(), which calls vt_waitactive().

There's a race in this path which causes the process which requests the
suspend to sleep indefinitely waiting for an event which already
happened:

P1                                      P2
 vt_move_to_console()
  set_console()
    schedule_console_callback()
  vt_waitactive()
    check n == fg_console +1
                                       console_callback()
                                         switch_screen()
                                         vt_event_post() // no waiters

    vt_event_wait() // forever

Fix the race by ensuring we're registered for the event before we check
if it's already completed.

Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-26 13:37:02 -07:00
Alan Cox 5d1a33fa55 vt: push the tty_lock down into the map handling
When we do this it becomes clear the lock we should be holding is the vc
lock, and in fact many of our other helpers are properly invoked this way.

We don't at this point guarantee not to race the keyboard code but the results
of that appear harmless and that was true before we started as well.

We now have no users of tty_lock in the console driver...

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-24 16:14:14 -07:00
Alan Cox 99cceb4e50 vt: waitevent is self locked so drop the tty_lock
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-08 11:10:28 -08:00
Alan Cox 20f62579dc vt: push down tioclinux cases
Some of this ventures into selection which is still a complete lost cause. We
are not making it any worse. It's completely busted anyway.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-08 11:10:27 -08:00
Alan Cox 4001d7b7fc vt: push down the tty lock so we can see what is left to tackle
At this point we have the tty_lock guarding a couple of oddities, plus the
translation and unimap still.

We also extend the console_lock in a couple of spots where coverage is wrong
and switch vcs_open to use the right lock !

[Fixed the locking issue Jiri reported]

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-08 11:10:27 -08:00
Alan Cox 079c9534a9 vt:tackle kbd_table
Keyboard struct lifetime is easy, but the locking is not and is completely
ignored by the existing code. Tackle this one head on

- Make the kbd_table private so we can run down all direct users
- Hoick the relevant ioctl handlers into the keyboard layer
- Lock them with the keyboard lock so they don't change mid keypress
- Add helpers for things like console stop/start so we isolate the poking
  around properly
- Tweak the braille console so it still builds

There are a couple of FIXME locking cases left for ioctls that are so hideous
they should be addressed in a later patch. After this patch the kbd_table is
private and all the keyboard jiggery pokery is in one place.

This update fixes speakup and also a memory leak in the original.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-08 10:50:35 -08:00
Alan Cox 247ff8e610 vt: lock the accent table
First step to debletcherising the vt console layer - pick a victim and fix
the locking

This is a nice simple object with its own rules so lets pick it out for
treatment. The user of the table already has a lock so we will also use the
same lock for updates.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-24 13:59:34 -08:00
Samuel Thibault cbcb834605 drivers/tty/vt/vt_ioctl.c: fix KDFONTOP 32bit compatibility layer
KDFONTOP(GET) currently fails with EIO when being run in a 32bit userland
with a 64bit kernel if the font width is not 8.

This is because of the setting of the KD_FONT_FLAG_OLD flag, which makes
con_font_get return EIO in such case.

This flag should *not* be set for KDFONTOP, since it's actually the whole
point of this flag (see comment in con_font_set for instance).

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Arthur Taylor <art@ified.ca>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-03 16:16:41 -08:00