Linux kernel
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code
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Pull char/misc driver fixes from Greg KH:
"Here are some small driver fixes, and one "large" revert, for
5.10-rc7.
They include:
- revert mei patch from 5.10-rc1 that was using a reserved userspace
value. It will be resubmitted once the proper id has been assigned
by the virtio people.
- habanalabs fixes found by the fall-through audit from Gustavo
- speakup driver fixes for reported issues
- fpga config build fix for reported issue.
All of these except the revert have been in linux-next with no
reported issues. The revert is "clean" and just removes a
previously-added driver, so no real issue there"
* tag 'char-misc-5.10-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
Revert "mei: virtio: virtualization frontend driver"
fpga: Specify HAS_IOMEM dependency for FPGA_DFL
habanalabs: put devices before driver removal
habanalabs: free host huge va_range if not used
speakup: Reject setting the speakup line discipline outside of speakup
Pull tty fixes from Greg KH:
"Here are two tty core fixes for 5.10-rc7.
They resolve some reported locking issues in the tty core. While they
have not been in a released linux-next yet, they have passed all of
the 0-day bot testing as well as the submitter's testing"
* tag 'tty-5.10-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
tty: Fix ->session locking
tty: Fix ->pgrp locking in tiocspgrp()
This reverts commit d162219c655c8cf8003128a13840d6c1e183fb80.
The device uses a VIRTIO device ID out of a not-for-production range.
Releasing Linux using an ID out of this range will make it conflict with
development setups. An official request to reserve an ID for an MEI
device is yet to be submitted to the virtio TC, thus there's no chance
it will be reserved and fixed in time before the next release.
Once requested it usually takes 2-3 weeks to land in the spec, which
means the device can be supported with the official ID in the next Linux
version if contributors act quickly.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Tomas Winkler <tomas.winkler@intel.com>
Cc: Alexander Usyskin <alexander.usyskin@intel.com>
Cc: Wang Yu <yu1.wang@intel.com>
Cc: Liu Shuo <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20201205193625.469773-1-mst@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull USB fixes from Greg KH:
"Here are some small USB fixes for 5.10-rc7 that resolve a number of
reported issues, and add some new device ids.
Nothing major here, but these solve some problems that people were
having with the 5.10-rc tree:
- reverts for USB storage dma settings that broke working devices
- thunderbolt use-after-free fix
- cdns3 driver fixes
- gadget driver userspace copy fix
- new device ids
All of these except for the reverts have been in linux-next with no
reported issues. The reverts are "clean" and were tested by Hans, as
well as passing the 0-day tests"
* tag 'usb-5.10-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: gadget: f_fs: Use local copy of descriptors for userspace copy
usb: ohci-omap: Fix descriptor conversion
Revert "usb-storage: fix sdev->host->dma_dev"
Revert "uas: fix sdev->host->dma_dev"
Revert "uas: bump hw_max_sectors to 2048 blocks for SS or faster drives"
USB: serial: kl5kusb105: fix memleak on open
USB: serial: ch341: sort device-id entries
USB: serial: ch341: add new Product ID for CH341A
USB: serial: option: fix Quectel BG96 matching
usb: cdns3: core: fix goto label for error path
usb: cdns3: gadget: clear trb->length as zero after preparing every trb
usb: cdns3: Fix hardware based role switch
USB: serial: option: add support for Thales Cinterion EXS82
USB: serial: option: add Fibocom NL668 variants
thunderbolt: Fix use-after-free in remove_unplugged_switch()
Currently, locking of ->session is very inconsistent; most places
protect it using the legacy tty mutex, but disassociate_ctty(),
__do_SAK(), tiocspgrp() and tiocgsid() don't.
Two of the writers hold the ctrl_lock (because they already need it for
->pgrp), but __proc_set_tty() doesn't do that yet.
On a PREEMPT=y system, an unprivileged user can theoretically abuse
this broken locking to read 4 bytes of freed memory via TIOCGSID if
tiocgsid() is preempted long enough at the right point. (Other things
might also go wrong, especially if root-only ioctls are involved; I'm
not sure about that.)
Change the locking on ->session such that:
- tty_lock() is held by all writers: By making disassociate_ctty()
hold it. This should be fine because the same lock can already be
taken through the call to tty_vhangup_session().
The tricky part is that we need to shorten the area covered by
siglock to be able to take tty_lock() without ugly retry logic; as
far as I can tell, this should be fine, since nothing in the
signal_struct is touched in the `if (tty)` branch.
- ctrl_lock is held by all writers: By changing __proc_set_tty() to
hold the lock a little longer.
- All readers that aren't holding tty_lock() hold ctrl_lock: By
adding locking to tiocgsid() and __do_SAK(), and expanding the area
covered by ctrl_lock in tiocspgrp().
Cc: stable@kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Because dfl.c uses the 'devm_ioremap', 'devm_iounmap',
'devm_ioremap_resource', and 'devm_platform_ioremap_resource'
functions, it should depend on HAS_IOMEM.
This fixes make allyesconfig under UML (ARCH=um), which doesn't provide
HAS_IOMEM.
[mdf@kernel.org: Removed "drivers: " in commit message]
Fixes: 89eb35e810a8 ("fpga: dfl: map feature mmio resources in their own feature drivers")
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Moritz Fischer <mdf@kernel.org>
Link: https://lore.kernel.org/r/20201122001549.107023-2-mdf@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull x86 fixes from Thomas Gleixner:
"A set of fixes for x86:
- Make the AMD L3 QoS code and data priorization enable/disable
mechanism work correctly.
The control bit was only set/cleared on one of the CPUs in a L3
domain, but it has to be modified on all CPUs in the domain. The
initial documentation was not clear about this, but the updated one
from Oct 2020 spells it out.
- Fix an off by one in the UV platform detection code which causes
the UV hubs to be identified wrongly.
The chip revisions start at 1 not at 0.
- Fix a long standing bug in the evaluation of prefixes in the
uprobes code which fails to handle repeated prefixes properly.
The aggregate size of the prefixes can be larger than the bytes
array but the code blindly iterated over the aggregate size beyond
the array boundary. Add a macro to handle this case properly and
use it at the affected places"
* tag 'x86-urgent-2020-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/sev-es: Use new for_each_insn_prefix() macro to loop over prefixes bytes
x86/insn-eval: Use new for_each_insn_prefix() macro to loop over prefixes bytes
x86/uprobes: Do not use prefixes.nbytes when looping over prefixes.bytes
x86/platform/uv: Fix UV4 hub revision adjustment
x86/resctrl: Fix AMD L3 QOS CDP enable/disable
The function may be unbound causing the ffs_ep and its descriptors
to be freed while userspace is in the middle of an ioctl requesting
the same descriptors. Avoid dangling pointer reference by first
making a local copy of desctiptors before releasing the spinlock.
Fixes: c559a3534109 ("usb: gadget: f_fs: add ioctl returning ep descriptor")
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Vamsi Krishna Samavedam <vskrishn@codeaurora.org>
Signed-off-by: Jack Pham <jackp@codeaurora.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201130203453.28154-1-jackp@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tiocspgrp() takes two tty_struct pointers: One to the tty that userspace
passed to ioctl() (`tty`) and one to the TTY being changed (`real_tty`).
These pointers are different when ioctl() is called with a master fd.
To properly lock real_tty->pgrp, we must take real_tty->ctrl_lock.
This bug makes it possible for racing ioctl(TIOCSPGRP, ...) calls on
both sides of a PTY pair to corrupt the refcount of `struct pid`,
leading to use-after-free errors.
Fixes: 47f86834bbd4 ("redo locking of tty->pgrp")
CC: stable@kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Oded writes:
This tag contains two bug fixes for v5.10-rc7:
- Memory leak every time a user closes the file-descriptor of the device.
The driver didn't always free all the VA range structures it maintains
per user.
- Memory leak every time the driver was removed. The device structure was
not "put" at the device's teardown function in the driver.
* tag 'misc-habanalabs-fixes-2020-11-30' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/ogabbay/linux:
habanalabs: put devices before driver removal
habanalabs: free host huge va_range if not used
Pull perf fixes from Thomas Gleixner:
"Two fixes for performance monitoring on X86:
- Add recursion protection to another callchain invoked from
x86_pmu_stop() which can recurse back into x86_pmu_stop(). The
first attempt to fix this missed this extra code path.
- Use the already filtered status variable to check for PEBS counter
overflow bits and not the unfiltered full status read from
IA32_PERF_GLOBAL_STATUS which can have unrelated bits check which
would be evaluated incorrectly"
* tag 'perf-urgent-2020-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: Check PEBS status correctly
perf/x86/intel: Fix a warning on x86_pmu_stop() with large PEBS
Since insn.prefixes.nbytes can be bigger than the size of
insn.prefixes.bytes[] when a prefix is repeated, the proper
check must be:
insn.prefixes.bytes[i] != 0 and i < 4
instead of using insn.prefixes.nbytes. Use the new
for_each_insn_prefix() macro which does it correctly.
Debugged by Kees Cook <keescook@chromium.org>.
[ bp: Massage commit message. ]
Fixes: 25189d08e516 ("x86/sev-es: Add support for handling IOIO exceptions")
Reported-by: syzbot+9b64b619f10f19d19a7c@syzkaller.appspotmail.com
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/160697106089.3146288.2052422845039649176.stgit@devnote2
There were a bunch of issues with the patch converting the
OMAP1 OSK board to use descriptors for controlling the USB
host:
- The chip label was incorrect
- The GPIO offset was off-by-one
- The code should use sleeping accessors
This patch tries to fix all issues at the same time.
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Fixes: 15d157e87443 ("usb: ohci-omap: Convert to use GPIO descriptors")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20201130083033.29435-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>