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Linux kernel
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SFC capability of video engines is not set correctly because i915
is testing for incorrect bits.
Fixes: c5d3e39caa45 ("drm/i915: Engine discovery query")
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Venkata Sandeep Dhanalakota <venkata.s.dhanalakota@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: <stable@vger.kernel.org> # v5.3+
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20201106011842.36203-1-daniele.ceraolospurio@intel.com
(cherry picked from commit ad18fa0f5f052046cad96fee762b5c64f42dd86a)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Move the specialised interactions with the physical GEM object from the
pread/pwrite ioctl handler into the phys backend.
Currently, if one is able to exhaust the entire aperture and then try to
pwrite into an object not backed by struct page, we accidentally invoked
the phys pwrite handler on a non-phys object; calamitous.
Fixes: c6790dc22312 ("drm/i915: Wean off drm_pci_alloc/drm_pci_free")
Testcase: igt/gem_pwrite/exhaustion
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Cc: stable@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20201105154934.16022-2-chris@chris-wilson.co.uk
(cherry picked from commit 852e1b3644817f071427b83859b889c788a0cf69)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
As there are more and more complicated interactions between the different
backing stores and userspace, push the control into the backends rather
than accumulate them all inside the ioctl handlers.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20201105154934.16022-1-chris@chris-wilson.co.uk
(cherry picked from commit 0049b688459b846f819b6e51c24cd0781fcfde41)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
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>
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