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Linux kernel
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several of them using the Restructured Text markup notation.
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Merge tag 'driver-core-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core documentation fixes from Greg KH:
"Some small Documentation fixes that were fallout from the larger
documentation update we did in 5.10-rc2.
Nothing major here at all, but all of these have been in linux-next
and resolve build warnings when building the documentation files"
* tag 'driver-core-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
Documentation: remove mic/index from misc-devices/index.rst
scripts: get_api.pl: Add sub-titles to ABI output
scripts: get_abi.pl: Don't let ABI files to create subtitles
docs: leds: index.rst: add a missing file
docs: ABI: sysfs-class-net: fix a typo
docs: ABI: sysfs-driver-dma-ioatdma: what starts with /sys
Pull tty/serial fixes from Greg KH:
"Here are a small number of small tty and serial fixes for some
reported problems for the tty core, vt code, and some serial drivers.
They include fixes for:
- a buggy and obsolete vt font ioctl removal
- 8250_mtk serial baudrate runtime warnings
- imx serial earlycon build configuration fix
- txx9 serial driver error path cleanup issues
- tty core fix in release_tty that can be triggered by trying to bind
an invalid serial port name to a speakup console device
Almost all of these have been in linux-next without any problems, the
only one that hasn't, just deletes code :)"
* tag 'tty-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
vt: Disable KD_FONT_OP_COPY
tty: fix crash in release_tty if tty->port is not set
serial: txx9: add missing platform_driver_unregister() on error in serial_txx9_init
tty: serial: imx: enable earlycon by default if IMX_SERIAL_CONSOLE is enabled
serial: 8250_mtk: Fix uart_get_baud_rate warning
With the recent removal of the misc/mic/ directory, the documentation
build now warns because we forgot about this index file.
Fix that up so that there are no more warnings here.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Sudeep Dutt <sudeep.dutt@intel.com>
Link: https://lore.kernel.org/r/20201103083408.GA2511903@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull USB fixes from Greg KH:
"Here are some small USB fixes and new device ids:
- USB gadget fixes for some reported issues
- Fixes for the ever-troublesome apple fastcharge driver, hopefully
we finally have it right.
- More USB core quirks for odd devices
- USB serial driver fixes for some long-standing issues that were
recently found
- some new USB serial driver device ids
All have been in linux-next with no reported issues"
* tag 'usb-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: apple-mfi-fastcharge: fix reference leak in apple_mfi_fc_set_property
usb: mtu3: fix panic in mtu3_gadget_stop()
USB: serial: option: add Telit FN980 composition 0x1055
USB: serial: option: add LE910Cx compositions 0x1203, 0x1230, 0x1231
USB: serial: cyberjack: fix write-URB completion race
USB: Add NO_LPM quirk for Kingston flash drive
USB: serial: option: add Quectel EC200T module support
usb: raw-gadget: fix memory leak in gadget_setup
usb: dwc2: Avoid leaving the error_debugfs label unused
usb: dwc3: ep0: Fix delay status handling
usb: gadget: fsl: fix null pointer checking
usb: gadget: goku_udc: fix potential crashes in probe
usb: dwc3: pci: add support for the Intel Alder Lake-S
It's buggy:
On Fri, Nov 06, 2020 at 10:30:08PM +0800, Minh Yuan wrote:
> We recently discovered a slab-out-of-bounds read in fbcon in the latest
> kernel ( v5.10-rc2 for now ). The root cause of this vulnerability is that
> "fbcon_do_set_font" did not handle "vc->vc_font.data" and
> "vc->vc_font.height" correctly, and the patch
> <https://lkml.org/lkml/2020/9/27/223> for VT_RESIZEX can't handle this
> issue.
>
> Specifically, we use KD_FONT_OP_SET to set a small font.data for tty6, and
> use KD_FONT_OP_SET again to set a large font.height for tty1. After that,
> we use KD_FONT_OP_COPY to assign tty6's vc_font.data to tty1's vc_font.data
> in "fbcon_do_set_font", while tty1 retains the original larger
> height. Obviously, this will cause an out-of-bounds read, because we can
> access a smaller vc_font.data with a larger vc_font.height.
Further there was only one user ever.
- Android's loadfont, busybox and console-tools only ever use OP_GET
and OP_SET
- fbset documentation only mentions the kernel cmdline font: option,
not anything else.
- systemd used OP_COPY before release 232 published in Nov 2016
Now unfortunately the crucial report seems to have gone down with
gmane, and the commit message doesn't say much. But the pull request
hints at OP_COPY being broken
https://github.com/systemd/systemd/pull/3651
So in other words, this never worked, and the only project which
foolishly every tried to use it, realized that rather quickly too.
Instead of trying to fix security issues here on dead code by adding
missing checks, fix the entire thing by removing the functionality.
Note that systemd code using the OP_COPY function ignored the return
value, so it doesn't matter what we're doing here really - just in
case a lone server somewhere happens to be extremely unlucky and
running an affected old version of systemd. The relevant code from
font_copy_to_all_vcs() in systemd was:
/* copy font from active VT, where the font was uploaded to */
cfo.op = KD_FONT_OP_COPY;
cfo.height = vcs.v_active-1; /* tty1 == index 0 */
(void) ioctl(vcfd, KDFONTOP, &cfo);
Note this just disables the ioctl, garbage collecting the now unused
callbacks is left for -next.
v2: Tetsuo found the old mail, which allowed me to find it on another
archive. Add the link too.
Acked-by: Peilin Ye <yepeilin.cs@gmail.com>
Reported-by: Minh Yuan <yuanmingbuaa@gmail.com>
References: https://lists.freedesktop.org/archives/systemd-devel/2016-June/036935.html
References: https://github.com/systemd/systemd/pull/3651
Cc: Greg KH <greg@kroah.com>
Cc: Peilin Ye <yepeilin.cs@gmail.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://lore.kernel.org/r/20201108153806.3140315-1-daniel.vetter@ffwll.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Instead of adding titles just for the files, add titles
for each part of the ABI output, in order to make easier
to search for a symbol there.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/64752a5de06ab8263c296e3ed01414b25861e1eb.1604312590.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
current->group_leader->exit_signal may change during copy_process() if
current->real_parent exits.
Move the assignment inside tasklist_lock to avoid the race.
Signed-off-by: Eddy Wu <eddy_wu@trendmicro.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johan writes:
USB-serial fixes for 5.10-rc3
Here's a fix for a long-standing issue with the cyberjack driver and
some new device ids.
All have been in linux-next with no reported issues.
* tag 'usb-serial-5.10-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
USB: serial: option: add Telit FN980 composition 0x1055
USB: serial: option: add LE910Cx compositions 0x1203, 0x1230, 0x1231
USB: serial: cyberjack: fix write-URB completion race
USB: serial: option: add Quectel EC200T module support
Commit 2ae0b31e0face ("tty: don't crash in tty_init_dev when missing
tty_port") didn't fully prevent the crash as the cleanup path in
tty_init_dev() calls release_tty() which dereferences tty->port
without checking it for non-null.
Add tty->port checks to release_tty to avoid the kernel crash.
Fixes: 2ae0b31e0face ("tty: don't crash in tty_init_dev when missing tty_port")
Signed-off-by: Matthias Reichl <hias@horus.com>
Link: https://lore.kernel.org/r/20201105123432.4448-1-hias@horus.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The ReST output should only contain documentation titles
automatically created by the script.
There are two reasons for that:
1) Consistency.
just a handful ABI docs define titles
2) To avoid critical errors.
Docutils (which is the basis for Sphinx) allows a free
assign of documentation title markups. So, one document
could be doing things like:
Level 1
=======
Level 2
-------
While another one could do the reverse:
Level 1
-------
Level 2
=======
But the same document can't mix.
As the output of get_abi.pl will join contents from multiple
files, if they don't define the levels on a consistent errors,
errors like this can happen:
Sphinx parallel build error:
docutils.utils.SystemMessage: /home/rdunlap/lnx/lnx-510-rc2/Documentation/ABI/testing/sysfs-bus-rapidio:2: (SEVERE/4) Title level inconsistent:
Attributes Common for All RapidIO Devices
-----------------------------------------
Which cause some versions of Sphinx to go into an endless
loop.
It should be noticed that an alternative to that would
be to replace all title occurrences by a single markup,
but that will make the parser more complex, and, due to
(1) it would generate an inconsistent output.
So, better to just remove the titles defined at the ABI
files from the output.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/6c62ef5c01d39dee8d891f8390c816d2a889670a.1604312590.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull xfs fixes from Darrick Wong:
- Fix an uninitialized struct problem
- Fix an iomap problem zeroing unwritten EOF blocks
- Fix some clumsy error handling when writeback fails on filesystems
with blocksize < pagesize
- Fix a retry loop not resetting loop variables properly
- Fix scrub flagging rtinherit inodes on a non-rt fs, since the kernel
actually does permit that combination
- Fix excessive page cache flushing when unsharing part of a file
* tag 'xfs-5.10-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: only flush the unshared range in xfs_reflink_unshare
xfs: fix scrub flagging rtinherit even if there is no rt device
xfs: fix missing CoW blocks writeback conversion retry
iomap: clean up writeback state logic on writepage error
iomap: support partial page discard on writeback block mapping failure
xfs: flush new eof page on truncate to avoid post-eof corruption
xfs: set xefi_discard when creating a deferred agfl free log intent item
pm_runtime_get_sync() will increment pm usage at first and it
will resume the device later. If runtime of the device has
error or device is in inaccessible state(or other error state),
resume operation will fail. If we do not call put operation to
decrease the reference, the result is that this device cannot
enter the idle state and always stay busy or other non-idle
state.
Fixes: 249fa8217b846 ("USB: Add driver to control USB fast charge for iOS devices")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201102022650.67115-1-zhangqilong3@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add the following Telit FN980 composition:
0x1055: tty, adb, tty, tty, tty, tty
Signed-off-by: Daniele Palmas <dnlplm@gmail.com>
Link: https://lore.kernel.org/r/20201103124425.12940-1-dnlplm@gmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
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