commit fa77ce201f upstream.
Programmable lab power supplies made by GW Instek, such as the
GPP-2323, have a USB port exposing a serial port to control the device.
Stringing the supplied Windows driver, references to the ch341 chip are
found. Binding the existing ch341 driver to the VID/PID of the GPP-2323
("GW Instek USB2.0-Serial" as per the USB product name) works out of the
box, communication and control is now possible.
This patch should work with any GPP series power supply due to
similarities in the product line.
Signed-off-by: Stephan Brunner <s.brunner@stephan-brunner.net>
Link: https://lore.kernel.org/r/4a47b864-0816-6f6a-efee-aa20e74bcdc6@stephan-brunner.net
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 75e5b4849b upstream.
Stall the control endpoint in case provided index exceeds array size of
MAX_CONFIG_INTERFACES or when the retrieved function pointer is null.
Signed-off-by: Szymon Heidrich <szymon.heidrich@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 117b4e96c7 upstream.
With CPU re-ordering on write instructions, there might
be a chance that the HWO is set before the TRB is updated
with the new mapped buffer address.
And in the case where core is processing a list of TRBs
it is possible that it fetched the TRBs when the HWO is set
but before the buffer address is updated.
Prevent this by adding a memory barrier before the HWO
is updated to ensure that the core always process the
updated TRBs.
Fixes: f6bafc6a1c ("usb: dwc3: convert TRBs into bitshifts")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Link: https://lore.kernel.org/r/1644207958-18287-1-git-send-email-quic_ugoswami@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ac55d16385 ]
Calling dwc2_hsotg_ep_disable on ep0 (in/out) will lead to the following
logs before returning -EINVAL:
dwc2 49000000.usb-otg: dwc2_hsotg_ep_disable: called for ep0
dwc2 49000000.usb-otg: dwc2_hsotg_ep_disable: called for ep0
To avoid these two logs while suspending, start disabling the endpoint
from the index 1, as done in dwc2_hsotg_udc_stop:
/* all endpoints should be shutdown */
for (ep = 1; ep < hsotg->num_of_eps; ep++) {
if (hsotg->eps_in[ep])
dwc2_hsotg_ep_disable_lock(&hsotg->eps_in[ep]->ep);
if (hsotg->eps_out[ep])
dwc2_hsotg_ep_disable_lock(&hsotg->eps_out[ep]->ep);
}
Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20211207130101.270314-1-amelie.delaunay@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 26fbe9772b upstream.
The syzbot fuzzer has identified a bug in which processes hang waiting
for usb_kill_urb() to return. It turns out the issue is not unlinking
the URB; that works just fine. Rather, the problem arises when the
wakeup notification that the URB has completed is not received.
The reason is memory-access ordering on SMP systems. In outline form,
usb_kill_urb() and __usb_hcd_giveback_urb() operating concurrently on
different CPUs perform the following actions:
CPU 0 CPU 1
---------------------------- ---------------------------------
usb_kill_urb(): __usb_hcd_giveback_urb():
... ...
atomic_inc(&urb->reject); atomic_dec(&urb->use_count);
... ...
wait_event(usb_kill_urb_queue,
atomic_read(&urb->use_count) == 0);
if (atomic_read(&urb->reject))
wake_up(&usb_kill_urb_queue);
Confining your attention to urb->reject and urb->use_count, you can
see that the overall pattern of accesses on CPU 0 is:
write urb->reject, then read urb->use_count;
whereas the overall pattern of accesses on CPU 1 is:
write urb->use_count, then read urb->reject.
This pattern is referred to in memory-model circles as SB (for "Store
Buffering"), and it is well known that without suitable enforcement of
the desired order of accesses -- in the form of memory barriers -- it
is entirely possible for one or both CPUs to execute their reads ahead
of their writes. The end result will be that sometimes CPU 0 sees the
old un-decremented value of urb->use_count while CPU 1 sees the old
un-incremented value of urb->reject. Consequently CPU 0 ends up on
the wait queue and never gets woken up, leading to the observed hang
in usb_kill_urb().
The same pattern of accesses occurs in usb_poison_urb() and the
failure pathway of usb_hcd_submit_urb().
The problem is fixed by adding suitable memory barriers. To provide
proper memory-access ordering in the SB pattern, a full barrier is
required on both CPUs. The atomic_inc() and atomic_dec() accesses
themselves don't provide any memory ordering, but since they are
present, we can use the optimized smp_mb__after_atomic() memory
barrier in the various routines to obtain the desired effect.
This patch adds the necessary memory barriers.
CC: <stable@vger.kernel.org>
Reported-and-tested-by: syzbot+76629376e06e2c2ad626@syzkaller.appspotmail.com
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/Ye8K0QYee0Q0Nna2@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5b67b31503 upstream.
Two people have reported (and mentioned numerous other reports on the
web) that VIA's VL817 USB-SATA bridge does not work with the uas
driver. Typical log messages are:
[ 3606.232149] sd 14:0:0:0: [sdg] tag#2 uas_zap_pending 0 uas-tag 1 inflight: CMD
[ 3606.232154] sd 14:0:0:0: [sdg] tag#2 CDB: Write(16) 8a 00 00 00 00 00 18 0c c9 80 00 00 00 80 00 00
[ 3606.306257] usb 4-4.4: reset SuperSpeed Plus Gen 2x1 USB device number 11 using xhci_hcd
[ 3606.328584] scsi host14: uas_eh_device_reset_handler success
Surprisingly, the devices do seem to work okay for some other people.
The cause of the differing behaviors is not known.
In the hope of getting the devices to work for the most users, even at
the possible cost of degraded performance for some, this patch adds an
unusual_devs entry for the VL817 to block it from binding to the uas
driver by default. Users will be able to override this entry by means
of a module parameter, if they want.
CC: <stable@vger.kernel.org>
Reported-by: DocMAX <mail@vacharakis.de>
Reported-and-tested-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/Ye8IsK2sjlEv1rqU@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 0055858638 ]
When a new USB device gets plugged to nested hubs, the affected hub,
which connects to usb 2-1.4-port2, doesn't report there's any change,
hence the nested hubs go back to runtime suspend like nothing happened:
[ 281.032951] usb usb2: usb wakeup-resume
[ 281.032959] usb usb2: usb auto-resume
[ 281.032974] hub 2-0:1.0: hub_resume
[ 281.033011] usb usb2-port1: status 0263 change 0000
[ 281.033077] hub 2-0:1.0: state 7 ports 4 chg 0000 evt 0000
[ 281.049797] usb 2-1: usb wakeup-resume
[ 281.069800] usb 2-1: Waited 0ms for CONNECT
[ 281.069810] usb 2-1: finish resume
[ 281.070026] hub 2-1:1.0: hub_resume
[ 281.070250] usb 2-1-port4: status 0203 change 0000
[ 281.070272] usb usb2-port1: resume, status 0
[ 281.070282] hub 2-1:1.0: state 7 ports 4 chg 0010 evt 0000
[ 281.089813] usb 2-1.4: usb wakeup-resume
[ 281.109792] usb 2-1.4: Waited 0ms for CONNECT
[ 281.109801] usb 2-1.4: finish resume
[ 281.109991] hub 2-1.4:1.0: hub_resume
[ 281.110147] usb 2-1.4-port2: status 0263 change 0000
[ 281.110234] usb 2-1-port4: resume, status 0
[ 281.110239] usb 2-1-port4: status 0203, change 0000, 10.0 Gb/s
[ 281.110266] hub 2-1.4:1.0: state 7 ports 4 chg 0000 evt 0000
[ 281.110426] hub 2-1.4:1.0: hub_suspend
[ 281.110565] usb 2-1.4: usb auto-suspend, wakeup 1
[ 281.130998] hub 2-1:1.0: hub_suspend
[ 281.137788] usb 2-1: usb auto-suspend, wakeup 1
[ 281.142935] hub 2-0:1.0: state 7 ports 4 chg 0000 evt 0000
[ 281.177828] usb 2-1: usb wakeup-resume
[ 281.197839] usb 2-1: Waited 0ms for CONNECT
[ 281.197850] usb 2-1: finish resume
[ 281.197984] hub 2-1:1.0: hub_resume
[ 281.198203] usb 2-1-port4: status 0203 change 0000
[ 281.198228] usb usb2-port1: resume, status 0
[ 281.198237] hub 2-1:1.0: state 7 ports 4 chg 0010 evt 0000
[ 281.217835] usb 2-1.4: usb wakeup-resume
[ 281.237834] usb 2-1.4: Waited 0ms for CONNECT
[ 281.237845] usb 2-1.4: finish resume
[ 281.237990] hub 2-1.4:1.0: hub_resume
[ 281.238067] usb 2-1.4-port2: status 0263 change 0000
[ 281.238148] usb 2-1-port4: resume, status 0
[ 281.238152] usb 2-1-port4: status 0203, change 0000, 10.0 Gb/s
[ 281.238166] hub 2-1.4:1.0: state 7 ports 4 chg 0000 evt 0000
[ 281.238385] hub 2-1.4:1.0: hub_suspend
[ 281.238523] usb 2-1.4: usb auto-suspend, wakeup 1
[ 281.258076] hub 2-1:1.0: hub_suspend
[ 281.265744] usb 2-1: usb auto-suspend, wakeup 1
[ 281.285976] hub 2-0:1.0: hub_suspend
[ 281.285988] usb usb2: bus auto-suspend, wakeup 1
USB 3.2 spec, 9.2.5.4 "Changing Function Suspend State" says that "If
the link is in a non-U0 state, then the device must transition the link
to U0 prior to sending the remote wake message", but the hub only
transits the link to U0 after signaling remote wakeup.
So be more forgiving and use a 20ms delay to let the link transit to U0
for remote wakeup.
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Link: https://lore.kernel.org/r/20211215120108.336597-1-kai.heng.feng@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c76ef96fc0 ]
Function fs endpoint file operations are synchronized via an interruptible
mutex wait. However we see threads that do ep file operations concurrently
are getting blocked for the mutex lock in __fdget_pos(). This is an
uninterruptible wait and we see hung task warnings and kernel panic
if hung_task_panic systcl is enabled if host does not send/receive
the data for long time.
The reason for threads getting blocked in __fdget_pos() is due to
the file position protection introduced by the commit 9c225f2655
("vfs: atomic f_pos accesses as per POSIX"). Since function fs
endpoint files does not have the notion of the file position, switch
to the stream mode. This will bypass the file position mutex and
threads will be blocked in interruptible state for the function fs
mutex.
It should not affects user space as we are only changing the task state
changes the task state from UNINTERRUPTIBLE to INTERRUPTIBLE while waiting
for the USB transfers to be finished. However there is a slight change to
the O_NONBLOCK behavior. Earlier threads that are using O_NONBLOCK are also
getting blocked inside fdget_pos(). Now they reach to function fs and error
code is returned. The non blocking behavior is actually honoured now.
Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Link: https://lore.kernel.org/r/1636712682-1226-1-git-send-email-quic_pkondeti@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 1d7d4c0793 upstream.
When the USB core code for getting root-hub status reports was
originally written, it was assumed that the hub driver would be its
only caller. But this isn't true now; user programs can use usbfs to
communicate with root hubs and get status reports. When they do this,
they may use a transfer_buffer that is smaller than the data returned
by the HCD, which will lead to a buffer overflow error when
usb_hcd_poll_rh_status() tries to store the status data. This was
discovered by syzbot:
BUG: KASAN: slab-out-of-bounds in memcpy include/linux/fortify-string.h:225 [inline]
BUG: KASAN: slab-out-of-bounds in usb_hcd_poll_rh_status+0x5f4/0x780 drivers/usb/core/hcd.c:776
Write of size 2 at addr ffff88801da403c0 by task syz-executor133/4062
This patch fixes the bug by reducing the amount of status data if it
won't fit in the transfer_buffer. If some data gets discarded then
the URB's completion status is set to -EOVERFLOW rather than 0, to let
the user know what happened.
Reported-and-tested-by: syzbot+3ae6a2b06f131ab9849f@syzkaller.appspotmail.com
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/Yc+3UIQJ2STbxNua@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0f663729bb upstream.
Bugzilla #213839 reports a 7-port hub that doesn't work properly when
devices are plugged into some of the ports; the kernel goes into an
unending disconnect/reinitialize loop as shown in the bug report.
This "7-port hub" comprises two four-port hubs with one plugged into
the other; the failures occur when a device is plugged into one of the
downstream hub's ports. (These hubs have other problems too. For
example, they bill themselves as USB-2.0 compliant but they only run
at full speed.)
It turns out that the failures are caused by bugs in both the kernel
and the hub. The hub's bug is that it reports a different
bmAttributes value in its configuration descriptor following a remote
wakeup (0xe0 before, 0xc0 after -- the wakeup-support bit has
changed).
The kernel's bug is inside the hub driver's resume handler. When
hub_activate() sees that one of the hub's downstream ports got a
wakeup request from a child device, it notes this fact by setting the
corresponding bit in the hub->change_bits variable. But this variable
is meant for connection changes, not wakeup events; setting it causes
the driver to believe the downstream port has been disconnected and
then connected again (in addition to having received a wakeup
request).
Because of this, the hub driver then tries to check whether the device
currently plugged into the downstream port is the same as the device
that had been attached there before. Normally this check succeeds and
wakeup handling continues with no harm done (which is why the bug
remained undetected until now). But with these dodgy hubs, the check
fails because the config descriptor has changed. This causes the hub
driver to reinitialize the child device, leading to the
disconnect/reinitialize loop described in the bug report.
The proper way to note reception of a downstream wakeup request is
to set a bit in the hub->event_bits variable instead of
hub->change_bits. That way the hub driver will realize that something
has happened to the port but will not think the port and child device
have been disconnected. This patch makes that change.
Cc: <stable@vger.kernel.org>
Tested-by: Jonathan McDowell <noodles@earth.li>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/YdCw7nSfWYPKWQoD@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e484409258 upstream.
The Fresco Logic FL1100 controller needs the TRUST_TX_LENGTH quirk like
other Fresco controllers, but should not have the BROKEN_MSI quirks set.
BROKEN_MSI quirk causes issues in detecting usb drives connected to docks
with this FL1100 controller.
The BROKEN_MSI flag was apparently accidentally set together with the
TRUST_TX_LENGTH quirk
Original patch went to stable so this should go there as well.
Fixes: ea0f69d821 ("xhci: Enable trust tx length quirk for Fresco FL11 USB controller")
Cc: stable@vger.kernel.org
cc: Nikolay Martynov <mar.kolya@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20211221112825.54690-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f08adf5add ]
Szymon rightly pointed out that the previous check for the endpoint
direction in bRequestType was not looking at only the bit involved, but
rather the whole value. Normally this is ok, but for some request
types, bits other than bit 8 could be set and the check for the endpoint
length could not stall correctly.
Fix that up by only checking the single bit.
Fixes: 153a2d7e33 ("USB: gadget: detect too-big endpoint 0 requests")
Cc: Felipe Balbi <balbi@kernel.org>
Reported-by: Szymon Heidrich <szymon.heidrich@gmail.com>
Link: https://lore.kernel.org/r/20211214184621.385828-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 86ebbc11bb upstream.
Under some conditions, USB gadget devices can show allocated buffer
contents to a host. Fix this up by zero-allocating them so that any
extra data will all just be zeros.
Reported-by: Szymon Heidrich <szymon.heidrich@gmail.com>
Tested-by: Szymon Heidrich <szymon.heidrich@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 153a2d7e33 upstream.
Sometimes USB hosts can ask for buffers that are too large from endpoint
0, which should not be allowed. If this happens for OUT requests, stall
the endpoint, but for IN requests, trim the request size to the endpoint
buffer size.
Co-developed-by: Szymon Heidrich <szymon.heidrich@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6ae6dc22d2 upstream.
xHC hardware can only have one slot in default state with address 0
waiting for a unique address at a time, otherwise "undefined behavior
may occur" according to xhci spec 5.4.3.4
The address0_mutex exists to prevent this across both xhci roothubs.
If hub_port_init() fails, it may unlock the mutex and exit with a xhci
slot in default state. If the other xhci roothub calls hub_port_init()
at this point we end up with two slots in default state.
Make sure the address0_mutex protects the slot default state across
hub_port_init() retries, until slot is addressed or disabled.
Note, one known minor case is not fixed by this patch.
If device needs to be reset during resume, but fails all hub_port_init()
retries in usb_reset_and_verify_device(), then it's possible the slot is
still left in default state when address0_mutex is unlocked.
Cc: <stable@vger.kernel.org>
Fixes: 638139eb95 ("usb: hub: allow to process more usb hub events in parallel")
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20211115221630.871204-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fc153aba3e upstream.
Instead of maintaining a single-linked list of devices that must be
searched linearly in .remove() just use spi_set_drvdata() to remember the
link between the spi device and the driver struct. Then the global list
and the next member can be dropped.
This simplifies the driver, reduces the memory footprint and the time to
search the list. Also it makes obvious that there is always a corresponding
driver struct for a given device in .remove(), so the error path for
!max3421_hcd can be dropped, too.
As a side effect this fixes a data inconsistency when .probe() races with
itself for a second max3421 device in manipulating max3421_hcd_list. A
similar race is fixed in .remove(), too.
Fixes: 2d53139f31 ("Add support for using a MAX3421E chip as a host driver.")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20211018204028.2914597-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9aaa81c336 upstream.
Chipidea core was calling the interrupt handler from non-IRQ context
with interrupts enabled, something which can lead to a deadlock if
there's an actual interrupt trying to take a lock that's already held
(e.g. the controller lock in udc_irq()).
Add a wrapper that can be used to fake interrupts instead of calling the
handler directly.
Fixes: 3ecb3e09b0 ("usb: chipidea: Use extcon framework for VBUS and ID detect")
Fixes: 876d4e1e82 ("usb: chipidea: core: add wakeup support for extcon")
Cc: Peter Chen <peter.chen@kernel.org>
Cc: stable@vger.kernel.org # 4.4
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211021083447.20078-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e1959faf08 upstream.
Some USB 3.1 enumeration issues were reported after the hub driver removed
the minimum 100ms limit for the power-on-good delay.
Since commit 90d28fb53d ("usb: core: reduce power-on-good delay time of
root hub") the hub driver sets the power-on-delay based on the
bPwrOn2PwrGood value in the hub descriptor.
xhci driver has a 20ms bPwrOn2PwrGood value for both roothubs based
on xhci spec section 5.4.8, but it's clearly not enough for the
USB 3.1 devices, causing enumeration issues.
Tests indicate full 100ms delay is needed.
Reported-by: Walt Jr. Brake <mr.yming81@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Fixes: 90d28fb53d ("usb: core: reduce power-on-good delay time of root hub")
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20211105160036.549516-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 21b5fcdccb upstream.
musb_gadget_queue() adds the passed request to musb_ep::req_list. If the
endpoint is idle and it is the first request then it invokes
musb_queue_resume_work(). If the function returns an error then the
error is passed to the caller without any clean-up and the request
remains enqueued on the list. If the caller enqueues the request again
then the list corrupts.
Remove the request from the list on error.
Fixes: ea2f35c01d ("usb: musb: Fix sleeping function called from invalid context for hdrc glue")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Viraj Shah <viraj.shah@linutronix.de>
Link: https://lore.kernel.org/r/20211021093644.4734-1-viraj.shah@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a0548b2690 upstream.
On 64-bit:
drivers/usb/gadget/udc/fsl_qe_udc.c: In function ‘qe_ep0_rx’:
drivers/usb/gadget/udc/fsl_qe_udc.c:842:13: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
842 | vaddr = (u32)phys_to_virt(in_be32(&bd->buf));
| ^
In file included from drivers/usb/gadget/udc/fsl_qe_udc.c:41:
drivers/usb/gadget/udc/fsl_qe_udc.c:843:28: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
843 | frame_set_data(pframe, (u8 *)vaddr);
| ^
The driver assumes physical and virtual addresses are 32-bit, hence it
cannot work on 64-bit platforms.
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20211027080849.3276289-1-geert@linux-m68k.org
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 65a205e611 upstream.
A recent change that started reporting break events to the line
discipline caused the tty-buffer insertions to no longer be serialised
by inserting events also from the completion handler for the interrupt
endpoint.
Completion calls for distinct endpoints are not guaranteed to be
serialised. For example, in case a host-controller driver uses
bottom-half completion, the interrupt and bulk-in completion handlers
can end up running in parallel on two CPUs (high-and low-prio tasklets,
respectively) thereby breaking the tty layer's single producer
assumption.
Fix this by holding the read lock also when inserting characters from
the bulk endpoint.
Fixes: 08dff274ed ("cdc-acm: fix BREAK rx code path adding necessary calls")
Cc: stable@vger.kernel.org
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210929090937.7410-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
