In VT_ACTIVATE an almost identical code path has been patched
with array_index_nospec. In the VT_DISALLOCATE path, the arg is
the user input from a system call argument and lately used as a index
for vc_cons[index].d access, which can be reached through path like
vt_disallocate->vc_busy or vt_disallocate->vc_deallocate.
For consistency both code paths should have the same mitigations
applied. Also, the code style is adjusted as suggested by Jiri.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Xiaomeng Tong <xiam0nd.tong@gmail.com>
Link: https://lore.kernel.org/r/20220314122921.31223-1-xiam0nd.tong@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
in vt_setactivate an almost identical code path has been patched
with array_index_nospec. In the VT_ACTIVATE path the user input
is from a system call argument instead of a usercopy.
For consistency both code paths should have the same mitigations
applied.
Kasper Acknowledgements: Jakob Koschel, Brian Johannesmeyer, Kaveh
Razavi, Herbert Bos, Cristiano Giuffrida from the VUSec group at VU
Amsterdam.
Co-developed-by: Brian Johannesmeyer <bjohannesmeyer@gmail.com>
Signed-off-by: Brian Johannesmeyer <bjohannesmeyer@gmail.com>
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Link: https://lore.kernel.org/r/20220127144406.3589293-2-jakobkoschel@gmail.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
array_index_nospec ensures that an out-of-bounds value is set to zero
on the transient path. Decreasing the value by one afterwards causes
a transient integer underflow. vsa.console should be decreased first
and then sanitized with array_index_nospec.
Kasper Acknowledgements: Jakob Koschel, Brian Johannesmeyer, Kaveh
Razavi, Herbert Bos, Cristiano Giuffrida from the VUSec group at VU
Amsterdam.
Co-developed-by: Brian Johannesmeyer <bjohannesmeyer@gmail.com>
Signed-off-by: Brian Johannesmeyer <bjohannesmeyer@gmail.com>
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Link: https://lore.kernel.org/r/20220127144406.3589293-1-jakobkoschel@gmail.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Restore the original intent of the VT_RESIZEX ioctl's `v_clin' parameter
which is the number of pixel rows per character (cell) rather than the
height of the font used.
For framebuffer devices the two values are always the same, because the
former is inferred from the latter one. For VGA used as a true text
mode device these two parameters are independent from each other: the
number of pixel rows per character is set in the CRT controller, while
font height is in fact hardwired to 32 pixel rows and fonts of heights
below that value are handled by padding their data with blanks when
loaded to hardware for use by the character generator. One can change
the setting in the CRT controller and it will update the screen contents
accordingly regardless of the font loaded.
The `v_clin' parameter is used by the `vgacon' driver to set the height
of the character cell and then the cursor position within. Make the
parameter explicit then, by defining a new `vc_cell_height' struct
member of `vc_data', set it instead of `vc_font.height' from `v_clin' in
the VT_RESIZEX ioctl, and then use it throughout the `vgacon' driver
except where actual font data is accessed which as noted above is
independent from the CRTC setting.
This way the framebuffer console driver is free to ignore the `v_clin'
parameter as irrelevant, as it always should have, avoiding any issues
attempts to give the parameter a meaning there could have caused, such
as one that has led to commit 988d076336 ("vt_ioctl: make VT_RESIZEX
behave like VT_RESIZE"):
"syzbot is reporting UAF/OOB read at bit_putcs()/soft_cursor() [1][2],
for vt_resizex() from ioctl(VT_RESIZEX) allows setting font height
larger than actual font height calculated by con_font_set() from
ioctl(PIO_FONT). Since fbcon_set_font() from con_font_set() allocates
minimal amount of memory based on actual font height calculated by
con_font_set(), use of vt_resizex() can cause UAF/OOB read for font
data."
The problem first appeared around Linux 2.5.66 which predates our repo
history, but the origin could be identified with the old MIPS/Linux repo
also at: <git://git.kernel.org/pub/scm/linux/kernel/git/ralf/linux.git>
as commit 9736a3546de7 ("Merge with Linux 2.5.66."), where VT_RESIZEX
code in `vt_ioctl' was updated as follows:
if (clin)
- video_font_height = clin;
+ vc->vc_font.height = clin;
making the parameter apply to framebuffer devices as well, perhaps due
to the use of "font" in the name of the original `video_font_height'
variable. Use "cell" in the new struct member then to avoid ambiguity.
References:
[1] https://syzkaller.appspot.com/bug?id=32577e96d88447ded2d3b76d71254fb855245837
[2] https://syzkaller.appspot.com/bug?id=6b8355d27b2b94fb5cedf4655e3a59162d9e48e3
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org # v2.6.12+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Revert the removal of code handling extra VT_RESIZEX ioctl's parameters
beyond those that VT_RESIZE supports, fixing a functional regression
causing `svgatextmode' not to resize the VT anymore.
As a consequence of the reverted change when the video adapter is
reprogrammed from the original say 80x25 text mode using a 9x16
character cell (720x400 pixel resolution) to say 80x37 text mode and the
same character cell (720x592 pixel resolution), the VT geometry does not
get updated and only upper two thirds of the screen are used for the VT,
and the lower part remains blank. The proportions change according to
text mode geometries chosen.
Revert the change verbatim then, bringing back previous VT resizing.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Fixes: 988d076336 ("vt_ioctl: make VT_RESIZEX behave like VT_RESIZE")
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
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>
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>
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>
syzbot is reporting UAF/OOB read at bit_putcs()/soft_cursor() [1][2], for
vt_resizex() from ioctl(VT_RESIZEX) allows setting font height larger than
actual font height calculated by con_font_set() from ioctl(PIO_FONT).
Since fbcon_set_font() from con_font_set() allocates minimal amount of
memory based on actual font height calculated by con_font_set(),
use of vt_resizex() can cause UAF/OOB read for font data.
VT_RESIZEX was introduced in Linux 1.3.3, but it is unclear that what
comes to the "+ more" part, and I couldn't find a user of VT_RESIZEX.
#define VT_RESIZE 0x5609 /* set kernel's idea of screensize */
#define VT_RESIZEX 0x560A /* set kernel's idea of screensize + more */
So far we are not aware of syzbot reports caused by setting non-zero value
to v_vlin parameter. But given that it is possible that nobody is using
VT_RESIZEX, we can try removing support for v_clin and v_vlin parameters.
Therefore, this patch effectively makes VT_RESIZEX behave like VT_RESIZE,
with emitting a message if somebody is still using v_clin and/or v_vlin
parameters.
[1] https://syzkaller.appspot.com/bug?id=32577e96d88447ded2d3b76d71254fb855245837
[2] https://syzkaller.appspot.com/bug?id=6b8355d27b2b94fb5cedf4655e3a59162d9e48e3
Reported-by: syzbot <syzbot+b308f5fd049fbbc6e74f@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+16469b5e8e5a72e9131e@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/4933b81b-9b1a-355b-df0e-9b31e8280ab9@i-love.sakura.ne.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge 5.9-rc3 into tty-next
We need the tty/serial fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Synchronize with others and check perm directly in vt_k_ioctl.
We do not need to pass perm to do_fontx_ioctl and do_unimap_ioctl then.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-38-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We create a new vt_io_ioctl here and move there all the IO ioctls. This
makes vt_ioctl significantly smaller.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-32-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We create a new vt_k_ioctl here and move there all the K* ioctls. This
makes vt_ioctl significantly smaller.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-31-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
They were used for the first parameter of put_user. But put_user accepts
constants in the parameter and also determines the type only by the
second parameter. So we can safely drop these helpers and simplify the
code a bit.
Including the removal of set_int label.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-30-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is still a leftover from BKL, when we locked it around vt_ioctl's
code. We can return instead of breaks in the switch loop. And we can
return in case of errors too. This allows for sifting of the code to the
left in some cases.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-29-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
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>
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>
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
...
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>
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>
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
...
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
