<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/usb/core, branch v4.4.243</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>USB: Add NO_LPM quirk for Kingston flash drive</title>
<updated>2020-11-10T09:22:21+00:00</updated>
<author>
<name>Alan Stern</name>
<email>stern@rowland.harvard.edu</email>
</author>
<published>2020-11-02T14:58:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fc3fcc09ee09fce82c9893d7d96cd5243b54740e'/>
<id>fc3fcc09ee09fce82c9893d7d96cd5243b54740e</id>
<content type='text'>
commit afaa2e745a246c5ab95103a65b1ed00101e1bc63 upstream.

In Bugzilla #208257, Julien Humbert reports that a 32-GB Kingston
flash drive spontaneously disconnects and reconnects, over and over.
Testing revealed that disabling Link Power Management for the drive
fixed the problem.

This patch adds a quirk entry for that drive to turn off LPM permanently.

CC: Hans de Goede &lt;jwrdegoede@fedoraproject.org&gt;
CC: &lt;stable@vger.kernel.org&gt;
Reported-and-tested-by: Julien Humbert &lt;julroy67@gmail.com&gt;
Signed-off-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Link: https://lore.kernel.org/r/20201102145821.GA1478741@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit afaa2e745a246c5ab95103a65b1ed00101e1bc63 upstream.

In Bugzilla #208257, Julien Humbert reports that a 32-GB Kingston
flash drive spontaneously disconnects and reconnects, over and over.
Testing revealed that disabling Link Power Management for the drive
fixed the problem.

This patch adds a quirk entry for that drive to turn off LPM permanently.

CC: Hans de Goede &lt;jwrdegoede@fedoraproject.org&gt;
CC: &lt;stable@vger.kernel.org&gt;
Reported-and-tested-by: Julien Humbert &lt;julroy67@gmail.com&gt;
Signed-off-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Link: https://lore.kernel.org/r/20201102145821.GA1478741@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>usb: core: Solve race condition in anchor cleanup functions</title>
<updated>2020-10-29T08:03:11+00:00</updated>
<author>
<name>Eli Billauer</name>
<email>eli.billauer@gmail.com</email>
</author>
<published>2020-07-31T05:46:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f087334c7ec65bccdf98e8b7b62e3ade200c8e8b'/>
<id>f087334c7ec65bccdf98e8b7b62e3ade200c8e8b</id>
<content type='text'>
[ Upstream commit fbc299437c06648afcc7891e6e2e6638dd48d4df ]

usb_kill_anchored_urbs() is commonly used to cancel all URBs on an
anchor just before releasing resources which the URBs rely on. By doing
so, users of this function rely on that no completer callbacks will take
place from any URB on the anchor after it returns.

However if this function is called in parallel with __usb_hcd_giveback_urb
processing a URB on the anchor, the latter may call the completer
callback after usb_kill_anchored_urbs() returns. This can lead to a
kernel panic due to use after release of memory in interrupt context.

The race condition is that __usb_hcd_giveback_urb() first unanchors the URB
and then makes the completer callback. Such URB is hence invisible to
usb_kill_anchored_urbs(), allowing it to return before the completer has
been called, since the anchor's urb_list is empty.

Even worse, if the racing completer callback resubmits the URB, it may
remain in the system long after usb_kill_anchored_urbs() returns.

Hence list_empty(&amp;anchor-&gt;urb_list), which is used in the existing
while-loop, doesn't reliably ensure that all URBs of the anchor are gone.

A similar problem exists with usb_poison_anchored_urbs() and
usb_scuttle_anchored_urbs().

This patch adds an external do-while loop, which ensures that all URBs
are indeed handled before these three functions return. This change has
no effect at all unless the race condition occurs, in which case the
loop will busy-wait until the racing completer callback has finished.
This is a rare condition, so the CPU waste of this spinning is
negligible.

The additional do-while loop relies on usb_anchor_check_wakeup(), which
returns true iff the anchor list is empty, and there is no
__usb_hcd_giveback_urb() in the system that is in the middle of the
unanchor-before-complete phase. The @suspend_wakeups member of
struct usb_anchor is used for this purpose, which was introduced to solve
another problem which the same race condition causes, in commit
6ec4147e7bdb ("usb-anchor: Delay usb_wait_anchor_empty_timeout wake up
till completion is done").

The surely_empty variable is necessary, because usb_anchor_check_wakeup()
must be called with the lock held to prevent races. However the spinlock
must be released and reacquired if the outer loop spins with an empty
URB list while waiting for the unanchor-before-complete passage to finish:
The completer callback may very well attempt to take the very same lock.

To summarize, using usb_anchor_check_wakeup() means that the patched
functions can return only when the anchor's list is empty, and there is
no invisible URB being processed. Since the inner while loop finishes on
the empty list condition, the new do-while loop will terminate as well,
except for when the said race condition occurs.

Signed-off-by: Eli Billauer &lt;eli.billauer@gmail.com&gt;
Acked-by: Oliver Neukum &lt;oneukum@suse.com&gt;
Acked-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Link: https://lore.kernel.org/r/20200731054650.30644-1-eli.billauer@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit fbc299437c06648afcc7891e6e2e6638dd48d4df ]

usb_kill_anchored_urbs() is commonly used to cancel all URBs on an
anchor just before releasing resources which the URBs rely on. By doing
so, users of this function rely on that no completer callbacks will take
place from any URB on the anchor after it returns.

However if this function is called in parallel with __usb_hcd_giveback_urb
processing a URB on the anchor, the latter may call the completer
callback after usb_kill_anchored_urbs() returns. This can lead to a
kernel panic due to use after release of memory in interrupt context.

The race condition is that __usb_hcd_giveback_urb() first unanchors the URB
and then makes the completer callback. Such URB is hence invisible to
usb_kill_anchored_urbs(), allowing it to return before the completer has
been called, since the anchor's urb_list is empty.

Even worse, if the racing completer callback resubmits the URB, it may
remain in the system long after usb_kill_anchored_urbs() returns.

Hence list_empty(&amp;anchor-&gt;urb_list), which is used in the existing
while-loop, doesn't reliably ensure that all URBs of the anchor are gone.

A similar problem exists with usb_poison_anchored_urbs() and
usb_scuttle_anchored_urbs().

This patch adds an external do-while loop, which ensures that all URBs
are indeed handled before these three functions return. This change has
no effect at all unless the race condition occurs, in which case the
loop will busy-wait until the racing completer callback has finished.
This is a rare condition, so the CPU waste of this spinning is
negligible.

The additional do-while loop relies on usb_anchor_check_wakeup(), which
returns true iff the anchor list is empty, and there is no
__usb_hcd_giveback_urb() in the system that is in the middle of the
unanchor-before-complete phase. The @suspend_wakeups member of
struct usb_anchor is used for this purpose, which was introduced to solve
another problem which the same race condition causes, in commit
6ec4147e7bdb ("usb-anchor: Delay usb_wait_anchor_empty_timeout wake up
till completion is done").

The surely_empty variable is necessary, because usb_anchor_check_wakeup()
must be called with the lock held to prevent races. However the spinlock
must be released and reacquired if the outer loop spins with an empty
URB list while waiting for the unanchor-before-complete passage to finish:
The completer callback may very well attempt to take the very same lock.

To summarize, using usb_anchor_check_wakeup() means that the patched
functions can return only when the anchor's list is empty, and there is
no invisible URB being processed. Since the inner while loop finishes on
the empty list condition, the new do-while loop will terminate as well,
except for when the said race condition occurs.

Signed-off-by: Eli Billauer &lt;eli.billauer@gmail.com&gt;
Acked-by: Oliver Neukum &lt;oneukum@suse.com&gt;
Acked-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Link: https://lore.kernel.org/r/20200731054650.30644-1-eli.billauer@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>USB: quirks: Add USB_QUIRK_IGNORE_REMOTE_WAKEUP quirk for BYD zhaoxin notebook</title>
<updated>2020-09-23T06:44:27+00:00</updated>
<author>
<name>Penghao</name>
<email>penghao@uniontech.com</email>
</author>
<published>2020-09-07T02:30:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c349187277b6e3cc3d7d2f1e0460bd18f6ca8f26'/>
<id>c349187277b6e3cc3d7d2f1e0460bd18f6ca8f26</id>
<content type='text'>
commit bcea6dafeeef7d1a6a8320a249aabf981d63b881 upstream.

Add a USB_QUIRK_IGNORE_REMOTE_WAKEUP quirk for the BYD zhaoxin notebook.
This notebook come with usb touchpad. And we would like to disable
touchpad wakeup on this notebook by default.

Signed-off-by: Penghao &lt;penghao@uniontech.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20200907023026.28189-1-penghao@uniontech.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit bcea6dafeeef7d1a6a8320a249aabf981d63b881 upstream.

Add a USB_QUIRK_IGNORE_REMOTE_WAKEUP quirk for the BYD zhaoxin notebook.
This notebook come with usb touchpad. And we would like to disable
touchpad wakeup on this notebook by default.

Signed-off-by: Penghao &lt;penghao@uniontech.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20200907023026.28189-1-penghao@uniontech.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>usb: Fix out of sync data toggle if a configured device is reconfigured</title>
<updated>2020-09-23T06:44:26+00:00</updated>
<author>
<name>Mathias Nyman</name>
<email>mathias.nyman@linux.intel.com</email>
</author>
<published>2020-09-01T08:25:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6a94540a84db51e59e8a243fe2966ab6a92f5c39'/>
<id>6a94540a84db51e59e8a243fe2966ab6a92f5c39</id>
<content type='text'>
commit cfd54fa83a5068b61b7eb28d3c117d8354c74c7a upstream.

Userspace drivers that use a SetConfiguration() request to "lightweight"
reset an already configured usb device might cause data toggles to get out
of sync between the device and host, and the device becomes unusable.

The xHCI host requires endpoints to be dropped and added back to reset the
toggle. If USB core notices the new configuration is the same as the
current active configuration it will avoid these extra steps by calling
usb_reset_configuration() instead of usb_set_configuration().

A SetConfiguration() request will reset the device side data toggles.
Make sure usb_reset_configuration() function also drops and adds back the
endpoints to ensure data toggles are in sync.

To avoid code duplication split the current usb_disable_device() function
and reuse the endpoint specific part.

Cc: stable &lt;stable@vger.kernel.org&gt;
Tested-by: Martin Thierer &lt;mthierer@gmail.com&gt;
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20200901082528.12557-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit cfd54fa83a5068b61b7eb28d3c117d8354c74c7a upstream.

Userspace drivers that use a SetConfiguration() request to "lightweight"
reset an already configured usb device might cause data toggles to get out
of sync between the device and host, and the device becomes unusable.

The xHCI host requires endpoints to be dropped and added back to reset the
toggle. If USB core notices the new configuration is the same as the
current active configuration it will avoid these extra steps by calling
usb_reset_configuration() instead of usb_set_configuration().

A SetConfiguration() request will reset the device side data toggles.
Make sure usb_reset_configuration() function also drops and adds back the
endpoints to ensure data toggles are in sync.

To avoid code duplication split the current usb_disable_device() function
and reuse the endpoint specific part.

Cc: stable &lt;stable@vger.kernel.org&gt;
Tested-by: Martin Thierer &lt;mthierer@gmail.com&gt;
Signed-off-by: Mathias Nyman &lt;mathias.nyman@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20200901082528.12557-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>USB: core: add helpers to retrieve endpoints</title>
<updated>2020-09-23T06:44:24+00:00</updated>
<author>
<name>Johan Hovold</name>
<email>johan@kernel.org</email>
</author>
<published>2017-03-17T10:35:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6c0359c083966ec7af79ff13d26accc12d13fc6f'/>
<id>6c0359c083966ec7af79ff13d26accc12d13fc6f</id>
<content type='text'>
commit 66a359390e7e34f9a4c489467234b107b3d76169 upstream.

Many USB drivers iterate over the available endpoints to find required
endpoints of a specific type and direction. Typically the endpoints are
required for proper function and a missing endpoint should abort probe.

To facilitate code reuse, add a helper to retrieve common endpoints
(bulk or interrupt, in or out) and four wrappers to find a single
endpoint.

Note that the helpers are marked as __must_check to serve as a reminder
to always verify that all expected endpoints are indeed present. This
also means that any optional endpoints, typically need to be looked up
through separate calls.

Signed-off-by: Johan Hovold &lt;johan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 66a359390e7e34f9a4c489467234b107b3d76169 upstream.

Many USB drivers iterate over the available endpoints to find required
endpoints of a specific type and direction. Typically the endpoints are
required for proper function and a missing endpoint should abort probe.

To facilitate code reuse, add a helper to retrieve common endpoints
(bulk or interrupt, in or out) and four wrappers to find a single
endpoint.

Note that the helpers are marked as __must_check to serve as a reminder
to always verify that all expected endpoints are indeed present. This
also means that any optional endpoints, typically need to be looked up
through separate calls.

Signed-off-by: Johan Hovold &lt;johan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>USB: quirks: Add no-lpm quirk for another Raydium touchscreen</title>
<updated>2020-09-03T09:19:27+00:00</updated>
<author>
<name>Kai-Heng Feng</name>
<email>kai.heng.feng@canonical.com</email>
</author>
<published>2020-07-31T05:16:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1fa308e648c1ef18eb56e8e316367bd6fc58ce2f'/>
<id>1fa308e648c1ef18eb56e8e316367bd6fc58ce2f</id>
<content type='text'>
commit 5967116e8358899ebaa22702d09b0af57fef23e1 upstream.

There's another Raydium touchscreen needs the no-lpm quirk:
[    1.339149] usb 1-9: New USB device found, idVendor=2386, idProduct=350e, bcdDevice= 0.00
[    1.339150] usb 1-9: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[    1.339151] usb 1-9: Product: Raydium Touch System
[    1.339152] usb 1-9: Manufacturer: Raydium Corporation
...
[    6.450497] usb 1-9: can't set config #1, error -110

BugLink: https://bugs.launchpad.net/bugs/1889446
Signed-off-by: Kai-Heng Feng &lt;kai.heng.feng@canonical.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20200731051622.28643-1-kai.heng.feng@canonical.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5967116e8358899ebaa22702d09b0af57fef23e1 upstream.

There's another Raydium touchscreen needs the no-lpm quirk:
[    1.339149] usb 1-9: New USB device found, idVendor=2386, idProduct=350e, bcdDevice= 0.00
[    1.339150] usb 1-9: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[    1.339151] usb 1-9: Product: Raydium Touch System
[    1.339152] usb 1-9: Manufacturer: Raydium Corporation
...
[    6.450497] usb 1-9: can't set config #1, error -110

BugLink: https://bugs.launchpad.net/bugs/1889446
Signed-off-by: Kai-Heng Feng &lt;kai.heng.feng@canonical.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20200731051622.28643-1-kai.heng.feng@canonical.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>usb: core: Add a helper function to check the validity of EP type in URB</title>
<updated>2020-07-22T07:10:05+00:00</updated>
<author>
<name>Takashi Iwai</name>
<email>tiwai@suse.de</email>
</author>
<published>2017-10-04T14:15:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5547c12c47d01ac44009cc814d2b94cabe6a3cea'/>
<id>5547c12c47d01ac44009cc814d2b94cabe6a3cea</id>
<content type='text'>
commit e901b9873876ca30a09253731bd3a6b00c44b5b0 upstream.

This patch adds a new helper function to perform a sanity check of the
given URB to see whether it contains a valid endpoint.  It's a light-
weight version of what usb_submit_urb() does, but without the kernel
warning followed by the stack trace, just returns an error code.

Especially for a driver that doesn't parse the descriptor but fills
the URB with the fixed endpoint (e.g. some quirks for non-compliant
devices), this kind of check is preferable at the probe phase before
actually submitting the urb.

Tested-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e901b9873876ca30a09253731bd3a6b00c44b5b0 upstream.

This patch adds a new helper function to perform a sanity check of the
given URB to see whether it contains a valid endpoint.  It's a light-
weight version of what usb_submit_urb() does, but without the kernel
warning followed by the stack trace, just returns an error code.

Especially for a driver that doesn't parse the descriptor but fills
the URB with the fixed endpoint (e.g. some quirks for non-compliant
devices), this kind of check is preferable at the probe phase before
actually submitting the urb.

Tested-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>usb: add USB_QUIRK_DELAY_INIT for Logitech C922</title>
<updated>2020-06-30T00:07:59+00:00</updated>
<author>
<name>Tomasz Meresiński</name>
<email>tomasz@meresinski.eu</email>
</author>
<published>2020-06-03T20:33:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e04cbde43abe9a2c94716fd35f634a4867fbe6bd'/>
<id>e04cbde43abe9a2c94716fd35f634a4867fbe6bd</id>
<content type='text'>
commit 5d8021923e8a8cc37a421a64e27c7221f0fee33c upstream.

The Logitech C922, just like other Logitech webcams,
needs the USB_QUIRK_DELAY_INIT or it will randomly
not respond after device connection

Signed-off-by: Tomasz Meresiński &lt;tomasz@meresinski.eu&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20200603203347.7792-1-tomasz@meresinski.eu
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5d8021923e8a8cc37a421a64e27c7221f0fee33c upstream.

The Logitech C922, just like other Logitech webcams,
needs the USB_QUIRK_DELAY_INIT or it will randomly
not respond after device connection

Signed-off-by: Tomasz Meresiński &lt;tomasz@meresinski.eu&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20200603203347.7792-1-tomasz@meresinski.eu
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>USB: core: Fix misleading driver bug report</title>
<updated>2020-05-27T14:40:24+00:00</updated>
<author>
<name>Alan Stern</name>
<email>stern@rowland.harvard.edu</email>
</author>
<published>2020-05-01T20:07:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b011419b32230caaf78bcde6b5ab30fbcc006148'/>
<id>b011419b32230caaf78bcde6b5ab30fbcc006148</id>
<content type='text'>
[ Upstream commit ac854131d9844f79e2fdcef67a7707227538d78a ]

The syzbot fuzzer found a race between URB submission to endpoint 0
and device reset.  Namely, during the reset we call usb_ep0_reinit()
because the characteristics of ep0 may have changed (if the reset
follows a firmware update, for example).  While usb_ep0_reinit() is
running there is a brief period during which the pointers stored in
udev-&gt;ep_in[0] and udev-&gt;ep_out[0] are set to NULL, and if an URB is
submitted to ep0 during that period, usb_urb_ep_type_check() will
report it as a driver bug.  In the absence of those pointers, the
routine thinks that the endpoint doesn't exist.  The log message looks
like this:

------------[ cut here ]------------
usb 2-1: BOGUS urb xfer, pipe 2 != type 2
WARNING: CPU: 0 PID: 9241 at drivers/usb/core/urb.c:478
usb_submit_urb+0x1188/0x1460 drivers/usb/core/urb.c:478

Now, although submitting an URB while the device is being reset is a
questionable thing to do, it shouldn't count as a driver bug as severe
as submitting an URB for an endpoint that doesn't exist.  Indeed,
endpoint 0 always exists, even while the device is in its unconfigured
state.

To prevent these misleading driver bug reports, this patch updates
usb_disable_endpoint() to avoid clearing the ep_in[] and ep_out[]
pointers when the endpoint being disabled is ep0.  There's no danger
of leaving a stale pointer in place, because the usb_host_endpoint
structure being pointed to is stored permanently in udev-&gt;ep0; it
doesn't get deallocated until the entire usb_device structure does.

Reported-and-tested-by: syzbot+db339689b2101f6f6071@syzkaller.appspotmail.com
Signed-off-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;

Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.2005011558590.903-100000@netrider.rowland.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit ac854131d9844f79e2fdcef67a7707227538d78a ]

The syzbot fuzzer found a race between URB submission to endpoint 0
and device reset.  Namely, during the reset we call usb_ep0_reinit()
because the characteristics of ep0 may have changed (if the reset
follows a firmware update, for example).  While usb_ep0_reinit() is
running there is a brief period during which the pointers stored in
udev-&gt;ep_in[0] and udev-&gt;ep_out[0] are set to NULL, and if an URB is
submitted to ep0 during that period, usb_urb_ep_type_check() will
report it as a driver bug.  In the absence of those pointers, the
routine thinks that the endpoint doesn't exist.  The log message looks
like this:

------------[ cut here ]------------
usb 2-1: BOGUS urb xfer, pipe 2 != type 2
WARNING: CPU: 0 PID: 9241 at drivers/usb/core/urb.c:478
usb_submit_urb+0x1188/0x1460 drivers/usb/core/urb.c:478

Now, although submitting an URB while the device is being reset is a
questionable thing to do, it shouldn't count as a driver bug as severe
as submitting an URB for an endpoint that doesn't exist.  Indeed,
endpoint 0 always exists, even while the device is in its unconfigured
state.

To prevent these misleading driver bug reports, this patch updates
usb_disable_endpoint() to avoid clearing the ep_in[] and ep_out[]
pointers when the endpoint being disabled is ep0.  There's no danger
of leaving a stale pointer in place, because the usb_host_endpoint
structure being pointed to is stored permanently in udev-&gt;ep0; it
doesn't get deallocated until the entire usb_device structure does.

Reported-and-tested-by: syzbot+db339689b2101f6f6071@syzkaller.appspotmail.com
Signed-off-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;

Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.2005011558590.903-100000@netrider.rowland.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>USB: hub: Fix handling of connect changes during sleep</title>
<updated>2020-05-02T15:20:45+00:00</updated>
<author>
<name>Alan Stern</name>
<email>stern@rowland.harvard.edu</email>
</author>
<published>2020-04-22T20:09:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2e80fd5aff9918b4400bd741387f00042c9e2766'/>
<id>2e80fd5aff9918b4400bd741387f00042c9e2766</id>
<content type='text'>
commit 9f952e26295d977dbfc6fedeaf8c4f112c818d37 upstream.

Commit 8099f58f1ecd ("USB: hub: Don't record a connect-change event
during reset-resume") wasn't very well conceived.  The problem it
tried to fix was that if a connect-change event occurred while the
system was asleep (such as a device disconnecting itself from the bus
when it is suspended and then reconnecting when it resumes)
requiring a reset-resume during the system wakeup transition, the hub
port's change_bit entry would remain set afterward.  This would cause
the hub driver to believe another connect-change event had occurred
after the reset-resume, which was wrong and would lead the driver to
send unnecessary requests to the device (which could interfere with a
firmware update).

The commit tried to fix this by not setting the change_bit during the
wakeup.  But this was the wrong thing to do; it means that when a
device is unplugged while the system is asleep, the hub driver doesn't
realize anything has happened: The change_bit flag which would tell it
to handle the disconnect event is clear.

The commit needs to be reverted and the problem fixed in a different
way.  Fortunately an alternative solution was noted in the commit's
Changelog: We can continue to set the change_bit entry in
hub_activate() but then clear it when a reset-resume occurs.  That way
the the hub driver will see the change_bit when a device is
disconnected but won't see it when the device is still present.

That's what this patch does.

Reported-and-tested-by: Peter Chen &lt;peter.chen@nxp.com&gt;
Signed-off-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Fixes: 8099f58f1ecd ("USB: hub: Don't record a connect-change event during reset-resume")
Tested-by: Paul Zimmerman &lt;pauldzim@gmail.com&gt;
CC: &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.2004221602480.11262-100000@iolanthe.rowland.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 9f952e26295d977dbfc6fedeaf8c4f112c818d37 upstream.

Commit 8099f58f1ecd ("USB: hub: Don't record a connect-change event
during reset-resume") wasn't very well conceived.  The problem it
tried to fix was that if a connect-change event occurred while the
system was asleep (such as a device disconnecting itself from the bus
when it is suspended and then reconnecting when it resumes)
requiring a reset-resume during the system wakeup transition, the hub
port's change_bit entry would remain set afterward.  This would cause
the hub driver to believe another connect-change event had occurred
after the reset-resume, which was wrong and would lead the driver to
send unnecessary requests to the device (which could interfere with a
firmware update).

The commit tried to fix this by not setting the change_bit during the
wakeup.  But this was the wrong thing to do; it means that when a
device is unplugged while the system is asleep, the hub driver doesn't
realize anything has happened: The change_bit flag which would tell it
to handle the disconnect event is clear.

The commit needs to be reverted and the problem fixed in a different
way.  Fortunately an alternative solution was noted in the commit's
Changelog: We can continue to set the change_bit entry in
hub_activate() but then clear it when a reset-resume occurs.  That way
the the hub driver will see the change_bit when a device is
disconnected but won't see it when the device is still present.

That's what this patch does.

Reported-and-tested-by: Peter Chen &lt;peter.chen@nxp.com&gt;
Signed-off-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Fixes: 8099f58f1ecd ("USB: hub: Don't record a connect-change event during reset-resume")
Tested-by: Paul Zimmerman &lt;pauldzim@gmail.com&gt;
CC: &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.2004221602480.11262-100000@iolanthe.rowland.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
</feed>
