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The syzbot fuzzer found that the interrupt-URB completion callback in
the cdc-wdm driver was taking too long, and the driver's immediate
resubmission of interrupt URBs with -EPROTO status combined with the
dummy-hcd emulation to cause a CPU lockup:
cdc_wdm 1-1:1.0: nonzero urb status received: -71
cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes
watchdog: BUG: soft lockup - CPU#0 stuck for 26s! [syz-executor782:6625]
CPU#0 Utilization every 4s during lockup:
#1: 98% system, 0% softirq, 3% hardirq, 0% idle
#2: 98% system, 0% softirq, 3% hardirq, 0% idle
#3: 98% system, 0% softirq, 3% hardirq, 0% idle
#4: 98% system, 0% softirq, 3% hardirq, 0% idle
#5: 98% system, 1% softirq, 3% hardirq, 0% idle
Modules linked in:
irq event stamp: 73096
hardirqs last enabled at (73095): [<ffff80008037bc00>] console_emit_next_record kernel/printk/printk.c:2935 [inline]
hardirqs last enabled at (73095): [<ffff80008037bc00>] console_flush_all+0x650/0xb74 kernel/printk/printk.c:2994
hardirqs last disabled at (73096): [<ffff80008af10b00>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline]
hardirqs last disabled at (73096): [<ffff80008af10b00>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551
softirqs last enabled at (73048): [<ffff8000801ea530>] softirq_handle_end kernel/softirq.c:400 [inline]
softirqs last enabled at (73048): [<ffff8000801ea530>] handle_softirqs+0xa60/0xc34 kernel/softirq.c:582
softirqs last disabled at (73043): [<ffff800080020de8>] __do_softirq+0x14/0x20 kernel/softirq.c:588
CPU: 0 PID: 6625 Comm: syz-executor782 Tainted: G W 6.10.0-rc2-syzkaller-g8867bbd4a056 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Testing showed that the problem did not occur if the two error
messages -- the first two lines above -- were removed; apparently adding
material to the kernel log takes a surprisingly large amount of time.
In any case, the best approach for preventing these lockups and to
avoid spamming the log with thousands of error messages per second is
to ratelimit the two dev_err() calls. Therefore we replace them with
dev_err_ratelimited().
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Suggested-by: Greg KH <gregkh@linuxfoundation.org>
Reported-and-tested-by: syzbot+5f996b83575ef4058638@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-usb/00000000000073d54b061a6a1c65@google.com/
Reported-and-tested-by: syzbot+1b2abad17596ad03dcff@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-usb/000000000000f45085061aa9b37e@google.com/
Fixes: 9908a32e94de ("USB: remove err() macro from usb class drivers")
Link: https://lore.kernel.org/linux-usb/40dfa45b-5f21-4eef-a8c1-51a2f320e267@rowland.harvard.edu/
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/29855215-52f5-4385-b058-91f42c2bee18@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When multiple streams are in use, multiple TDs might be in flight when
an endpoint is stopped. We need to issue a Set TR Dequeue Pointer for
each, to ensure everything is reset properly and the caches cleared.
Change the logic so that any N>1 TDs found active for different streams
are deferred until after the first one is processed, calling
xhci_invalidate_cancelled_tds() again from xhci_handle_cmd_set_deq() to
queue another command until we are done with all of them. Also change
the error/"should never happen" paths to ensure we at least clear any
affected TDs, even if we can't issue a command to clear the hardware
cache, and complain loudly with an xhci_warn() if this ever happens.
This problem case dates back to commit e9df17eb1408 ("USB: xhci: Correct
assumptions about number of rings per endpoint.") early on in the XHCI
driver's life, when stream support was first added.
It was then identified but not fixed nor made into a warning in commit
674f8438c121 ("xhci: split handling halted endpoints into two steps"),
which added a FIXME comment for the problem case (without materially
changing the behavior as far as I can tell, though the new logic made
the problem more obvious).
Then later, in commit 94f339147fc3 ("xhci: Fix failure to give back some
cached cancelled URBs."), it was acknowledged again.
[Mathias: commit 94f339147fc3 ("xhci: Fix failure to give back some cached
cancelled URBs.") was a targeted regression fix to the previously mentioned
patch. Users reported issues with usb stuck after unmounting/disconnecting
UAS devices. This rolled back the TD clearing of multiple streams to its
original state.]
Apparently the commit author was aware of the problem (yet still chose
to submit it): It was still mentioned as a FIXME, an xhci_dbg() was
added to log the problem condition, and the remaining issue was mentioned
in the commit description. The choice of making the log type xhci_dbg()
for what is, at this point, a completely unhandled and known broken
condition is puzzling and unfortunate, as it guarantees that no actual
users would see the log in production, thereby making it nigh
undebuggable (indeed, even if you turn on DEBUG, the message doesn't
really hint at there being a problem at all).
It took me *months* of random xHC crashes to finally find a reliable
repro and be able to do a deep dive debug session, which could all have
been avoided had this unhandled, broken condition been actually reported
with a warning, as it should have been as a bug intentionally left in
unfixed (never mind that it shouldn't have been left in at all).
> Another fix to solve clearing the caches of all stream rings with
> cancelled TDs is needed, but not as urgent.
3 years after that statement and 14 years after the original bug was
introduced, I think it's finally time to fix it. And maybe next time
let's not leave bugs unfixed (that are actually worse than the original
bug), and let's actually get people to review kernel commits please.
Fixes xHC crashes and IOMMU faults with UAS devices when handling
errors/faults. Easiest repro is to use `hdparm` to mark an early sector
(e.g. 1024) on a disk as bad, then `cat /dev/sdX > /dev/null` in a loop.
At least in the case of JMicron controllers, the read errors end up
having to cancel two TDs (for two queued requests to different streams)
and the one that didn't get cleared properly ends up faulting the xHC
entirely when it tries to access DMA pages that have since been unmapped,
referred to by the stale TDs. This normally happens quickly (after two
or three loops). After this fix, I left the `cat` in a loop running
overnight and experienced no xHC failures, with all read errors
recovered properly. Repro'd and tested on an Apple M1 Mac Mini
(dwc3 host).
On systems without an IOMMU, this bug would instead silently corrupt
freed memory, making this a security bug (even on systems with IOMMUs
this could silently corrupt memory belonging to other USB devices on the
same controller, so it's still a security bug). Given that the kernel
autoprobes partition tables, I'm pretty sure a malicious USB device
pretending to be a UAS device and reporting an error with the right
timing could deliberately trigger a UAF and write to freed memory, with
no user action.
[Mathias: Commit message and code comment edit, original at:]
https://lore.kernel.org/linux-usb/20240524-xhci-streams-v1-1-6b1f13819bea@marcan.st/
Fixes: e9df17eb1408 ("USB: xhci: Correct assumptions about number of rings per endpoint.")
Fixes: 94f339147fc3 ("xhci: Fix failure to give back some cached cancelled URBs.")
Fixes: 674f8438c121 ("xhci: split handling halted endpoints into two steps")
Cc: stable@vger.kernel.org
Cc: security@kernel.org
Reviewed-by: Neal Gompa <neal@gompa.dev>
Signed-off-by: Hector Martin <marcan@marcan.st>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20240611120610.3264502-5-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As described in commit 8f873c1ff4ca ("xhci: Blacklist using streams on the
Etron EJ168 controller"), EJ188 have the same issue as EJ168, where Streams
do not work reliable on EJ188. So apply XHCI_BROKEN_STREAMS quirk to EJ188
as well.
Cc: stable@vger.kernel.org
Signed-off-by: Kuangyi Chiang <ki.chiang65@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20240611120610.3264502-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As described in commit c877b3b2ad5c ("xhci: Add reset on resume quirk for
asrock p67 host"), EJ188 have the same issue as EJ168, where completely
dies on resume. So apply XHCI_RESET_ON_RESUME quirk to EJ188 as well.
Cc: stable@vger.kernel.org
Signed-off-by: Kuangyi Chiang <ki.chiang65@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20240611120610.3264502-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The transferred length is set incorrectly for cancelled bulk
transfer TDs in case the bulk transfer ring stops on the last transfer
block with a 'Stop - Length Invalid' completion code.
length essentially ends up being set to the requested length:
urb->actual_length = urb->transfer_buffer_length
Length for 'Stop - Length Invalid' cases should be the sum of all
TRB transfer block lengths up to the one the ring stopped on,
_excluding_ the one stopped on.
Fix this by always summing up TRB lengths for 'Stop - Length Invalid'
bulk cases.
This issue was discovered by Alan Stern while debugging
https://bugzilla.kernel.org/show_bug.cgi?id=218890, but does not
solve that bug. Issue is older than 4.10 kernel but fix won't apply
to those due to major reworks in that area.
Tested-by: Pierre Tomon <pierretom+12@ik.me>
Cc: stable@vger.kernel.org # v4.10+
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20240611120610.3264502-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Mika writes:
thunderbolt: Fix for v6.10-rc3
This includes one USB4/Thunderbolt fix for v6.10-rc3:
- Fix lane margining debugfs node creation condition.
This has been in linux-next with no reported issues.
The member "uzonesize" of struct alauda_info will remain 0
if alauda_init_media() fails, potentially causing divide errors
in alauda_read_data() and alauda_write_lba().
- Add a member "media_initialized" to struct alauda_info.
- Change a condition in alauda_check_media() to ensure the
first initialization.
- Add an error check for the return value of alauda_init_media().
Fixes: e80b0fade09e ("[PATCH] USB Storage: add alauda support")
Reported-by: xingwei lee <xrivendell7@gmail.com>
Reported-by: yue sun <samsun1006219@gmail.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Shichao Lai <shichaorai@gmail.com>
Link: https://lore.kernel.org/r/20240526012745.2852061-1-shichaorai@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The margin debugfs node controls the "Enable Margin Test" field of the
lane margining operations. This field selects between either low or high
voltage margin values for voltage margin test or left or right timing
margin values for timing margin test.
According to the USB4 specification, whether or not the "Enable Margin
Test" control applies, depends on the values of the "Independent
High/Low Voltage Margin" or "Independent Left/Right Timing Margin"
capability fields for voltage and timing margin tests respectively. The
pre-existing condition enabled the debugfs node also in the case where
both low/high or left/right margins are returned, which is incorrect.
This change only enables the debugfs node in question, if the specific
required capability values are met.
Signed-off-by: Aapo Vienamo <aapo.vienamo@linux.intel.com>
Fixes: d0f1e0c2a699 ("thunderbolt: Add support for receiver lane margining")
Cc: stable@vger.kernel.org
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
It is possible that also the GET_ERROR command fails. If
that happens, the command completion still needs to be
acknowledged. Otherwise the interface will be stuck until
it's reset.
Reported-by: Ammy Yi <ammy.yi@intel.com>
Fixes: bdc62f2bae8f ("usb: typec: ucsi: Simplified registration and I/O API")
Cc: stable@vger.kernel.org
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240531104653.1303519-1-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After commit 8fea0c8fda30 ("usb: core: hcd: Convert from tasklet to BH
workqueue"), usb_giveback_urb_bh() runs in the BH workqueue with
interrupts enabled.
Thus, the remote coverage collection section in usb_giveback_urb_bh()->
__usb_hcd_giveback_urb() might be interrupted, and the interrupt handler
might invoke __usb_hcd_giveback_urb() again.
This breaks KCOV, as it does not support nested remote coverage collection
sections within the same context (neither in task nor in softirq).
Update kcov_remote_start/stop_usb_softirq() to disable interrupts for the
duration of the coverage collection section to avoid nested sections in
the softirq context (in addition to such in the task context, which are
already handled).
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Closes: https://lore.kernel.org/linux-usb/0f4d1964-7397-485b-bc48-11c01e2fcbca@I-love.SAKURA.ne.jp/
Closes: https://syzkaller.appspot.com/bug?extid=0438378d6f157baae1a2
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Fixes: 8fea0c8fda30 ("usb: core: hcd: Convert from tasklet to BH workqueue")
Cc: stable@vger.kernel.org
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20240527173538.4989-1-andrey.konovalov@linux.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
percpu.h depends on smp.h, but doesn't include it directly because of
circular header dependency issues; percpu.h is needed in a bunch of low
level headers.
This fixes a randconfig build error on mips:
include/linux/alloc_tag.h: In function '__alloc_tag_ref_set':
include/asm-generic/percpu.h:31:40: error: implicit declaration of function 'raw_smp_processor_id' [-Werror=implicit-function-declaration]
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 24e44cc22aa3 ("mm: percpu: enable per-cpu allocation tagging")
Closes: https://lore.kernel.org/oe-kbuild-all/202405210052.DIrMXJNz-lkp@intel.com/
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All nodes need an explicit additionalProperties or unevaluatedProperties
unless a $ref has one that's false. As that is not the case with
usb-device.yaml, "additionalProperties" is needed here.
Fixes: c44d9dab31d6 ("dt-bindings: usb: Add downstream facing ports to realtek binding")
Signed-off-by: "Rob Herring (Arm)" <robh@kernel.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20240523194500.2958192-1-robh@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull perf tool fix from Arnaldo Carvalho de Melo:
"Revert a patch causing a regression.
This made a simple 'perf record -e cycles:pp make -j199' stop working
on the Ampere ARM64 system Linus uses to test ARM64 kernels".
* tag 'perf-tools-fixes-for-v6.10-1-2024-05-26' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools:
Revert "perf parse-events: Prefer sysfs/JSON hardware events over legacy"
Similar to what fixed in Commit a6fe37f428c1 ("usb: typec: tcpm: Skip
hard reset when in error recovery"), the handling of the received Hard
Reset has to be skipped during TOGGLING state.
[ 4086.021288] VBUS off
[ 4086.021295] pending state change SNK_READY -> SNK_UNATTACHED @ 650 ms [rev2 NONE_AMS]
[ 4086.022113] VBUS VSAFE0V
[ 4086.022117] state change SNK_READY -> SNK_UNATTACHED [rev2 NONE_AMS]
[ 4086.022447] VBUS off
[ 4086.022450] state change SNK_UNATTACHED -> SNK_UNATTACHED [rev2 NONE_AMS]
[ 4086.023060] VBUS VSAFE0V
[ 4086.023064] state change SNK_UNATTACHED -> SNK_UNATTACHED [rev2 NONE_AMS]
[ 4086.023070] disable BIST MODE TESTDATA
[ 4086.023766] disable vbus discharge ret:0
[ 4086.023911] Setting usb_comm capable false
[ 4086.028874] Setting voltage/current limit 0 mV 0 mA
[ 4086.028888] polarity 0
[ 4086.030305] Requesting mux state 0, usb-role 0, orientation 0
[ 4086.033539] Start toggling
[ 4086.038496] state change SNK_UNATTACHED -> TOGGLING [rev2 NONE_AMS]
// This Hard Reset is unexpected
[ 4086.038499] Received hard reset
[ 4086.038501] state change TOGGLING -> HARD_RESET_START [rev2 HARD_RESET]
Fixes: f0690a25a140 ("staging: typec: USB Type-C Port Manager (tcpm)")
Cc: stable@vger.kernel.org
Signed-off-by: Kyle Tso <kyletso@google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20240520154858.1072347-1-kyletso@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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