linux-stable.git/drivers/usb, branch v4.4.262 Linux kernel stable tree usbip: fix stub_dev usbip_sockfd_store() races leading to gpf 2021-03-17T15:07:21+00:00 Shuah Khan skhan@linuxfoundation.org 2021-03-08T03:53:29+00:00 9ee196f307ec006cac386a0d8b7935dd2ccd0083 commit 9380afd6df70e24eacbdbde33afc6a3950965d22 upstream. usbip_sockfd_store() is invoked when user requests attach (import) detach (unimport) usb device from usbip host. vhci_hcd sends import request and usbip_sockfd_store() exports the device if it is free for export. Export and unexport are governed by local state and shared state - Shared state (usbip device status, sockfd) - sockfd and Device status are used to determine if stub should be brought up or shut down. - Local state (tcp_socket, rx and tx thread task_struct ptrs) A valid tcp_socket controls rx and tx thread operations while the device is in exported state. - While the device is exported, device status is marked used and socket, sockfd, and thread pointers are valid. Export sequence (stub-up) includes validating the socket and creating receive (rx) and transmit (tx) threads to talk to the client to provide access to the exported device. rx and tx threads depends on local and shared state to be correct and in sync. Unexport (stub-down) sequence shuts the socket down and stops the rx and tx threads. Stub-down sequence relies on local and shared states to be in sync. There are races in updating the local and shared status in the current stub-up sequence resulting in crashes. These stem from starting rx and tx threads before local and global state is updated correctly to be in sync. 1. Doesn't handle kthread_create() error and saves invalid ptr in local state that drives rx and tx threads. 2. Updates tcp_socket and sockfd, starts stub_rx and stub_tx threads before updating usbip_device status to SDEV_ST_USED. This opens up a race condition between the threads and usbip_sockfd_store() stub up and down handling. Fix the above problems: - Stop using kthread_get_run() macro to create/start threads. - Create threads and get task struct reference. - Add kthread_create() failure handling and bail out. - Hold usbip_device lock to update local and shared states after creating rx and tx threads. - Update usbip_device status to SDEV_ST_USED. - Update usbip_device tcp_socket, sockfd, tcp_rx, and tcp_tx - Start threads after usbip_device (tcp_socket, sockfd, tcp_rx, tcp_tx, and status) is complete. Credit goes to syzbot and Tetsuo Handa for finding and root-causing the kthread_get_run() improper error handling problem and others. This is a hard problem to find and debug since the races aren't seen in a normal case. Fuzzing forces the race window to be small enough for the kthread_get_run() error path bug and starting threads before updating the local and shared state bug in the stub-up sequence. Tested with syzbot reproducer: - https://syzkaller.appspot.com/text?tag=ReproC&x=14801034d00000 Fixes: 9720b4bc76a83807 ("staging/usbip: convert to kthread") Cc: stable@vger.kernel.org Reported-by: syzbot <syzbot+a93fba6d384346a761e3@syzkaller.appspotmail.com> Reported-by: syzbot <syzbot+bf1a360e305ee719e364@syzkaller.appspotmail.com> Reported-by: syzbot <syzbot+95ce4b142579611ef0a9@syzkaller.appspotmail.com> Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org> Link: https://lore.kernel.org/r/268a0668144d5ff36ec7d87fdfa90faf583b7ccc.1615171203.git.skhan@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 9380afd6df70e24eacbdbde33afc6a3950965d22 upstream.

usbip_sockfd_store() is invoked when user requests attach (import)
detach (unimport) usb device from usbip host. vhci_hcd sends import
request and usbip_sockfd_store() exports the device if it is free
for export.

Export and unexport are governed by local state and shared state
- Shared state (usbip device status, sockfd) - sockfd and Device
  status are used to determine if stub should be brought up or shut
  down.
- Local state (tcp_socket, rx and tx thread task_struct ptrs)
  A valid tcp_socket controls rx and tx thread operations while the
  device is in exported state.
- While the device is exported, device status is marked used and socket,
  sockfd, and thread pointers are valid.

Export sequence (stub-up) includes validating the socket and creating
receive (rx) and transmit (tx) threads to talk to the client to provide
access to the exported device. rx and tx threads depends on local and
shared state to be correct and in sync.

Unexport (stub-down) sequence shuts the socket down and stops the rx and
tx threads. Stub-down sequence relies on local and shared states to be
in sync.

There are races in updating the local and shared status in the current
stub-up sequence resulting in crashes. These stem from starting rx and
tx threads before local and global state is updated correctly to be in
sync.

1. Doesn't handle kthread_create() error and saves invalid ptr in local
   state that drives rx and tx threads.
2. Updates tcp_socket and sockfd,  starts stub_rx and stub_tx threads
   before updating usbip_device status to SDEV_ST_USED. This opens up a
   race condition between the threads and usbip_sockfd_store() stub up
   and down handling.

Fix the above problems:
- Stop using kthread_get_run() macro to create/start threads.
- Create threads and get task struct reference.
- Add kthread_create() failure handling and bail out.
- Hold usbip_device lock to update local and shared states after
  creating rx and tx threads.
- Update usbip_device status to SDEV_ST_USED.
- Update usbip_device tcp_socket, sockfd, tcp_rx, and tcp_tx
- Start threads after usbip_device (tcp_socket, sockfd, tcp_rx, tcp_tx,
  and status) is complete.

Credit goes to syzbot and Tetsuo Handa for finding and root-causing the
kthread_get_run() improper error handling problem and others. This is a
hard problem to find and debug since the races aren't seen in a normal
case. Fuzzing forces the race window to be small enough for the
kthread_get_run() error path bug and starting threads before updating the
local and shared state bug in the stub-up sequence.

Tested with syzbot reproducer:
- https://syzkaller.appspot.com/text?tag=ReproC&x=14801034d00000

Fixes: 9720b4bc76a83807 ("staging/usbip: convert to kthread")
Cc: stable@vger.kernel.org
Reported-by: syzbot <syzbot+a93fba6d384346a761e3@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+bf1a360e305ee719e364@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+95ce4b142579611ef0a9@syzkaller.appspotmail.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/268a0668144d5ff36ec7d87fdfa90faf583b7ccc.1615171203.git.skhan@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usbip: fix vhci_hcd to check for stream socket 2021-03-17T15:07:21+00:00 Shuah Khan skhan@linuxfoundation.org 2021-03-08T03:53:27+00:00 8bface75505077ec0412358a0db636accf1e5fbe commit f55a0571690c4aae03180e001522538c0927432f upstream. Fix attach_store() to validate the passed in file descriptor is a stream socket. If the file descriptor passed was a SOCK_DGRAM socket, sock_recvmsg() can't detect end of stream. Cc: stable@vger.kernel.org Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org> Link: https://lore.kernel.org/r/52712aa308915bda02cece1589e04ee8b401d1f3.1615171203.git.skhan@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f55a0571690c4aae03180e001522538c0927432f upstream.

Fix attach_store() to validate the passed in file descriptor is a
stream socket. If the file descriptor passed was a SOCK_DGRAM socket,
sock_recvmsg() can't detect end of stream.

Cc: stable@vger.kernel.org
Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/52712aa308915bda02cece1589e04ee8b401d1f3.1615171203.git.skhan@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usbip: fix stub_dev to check for stream socket 2021-03-17T15:07:21+00:00 Shuah Khan skhan@linuxfoundation.org 2021-03-08T03:53:26+00:00 70d35bf3ce4f3d3d2ed727491c1d22b5f908112b commit 47ccc8fc2c9c94558b27b6f9e2582df32d29e6e8 upstream. Fix usbip_sockfd_store() to validate the passed in file descriptor is a stream socket. If the file descriptor passed was a SOCK_DGRAM socket, sock_recvmsg() can't detect end of stream. Cc: stable@vger.kernel.org Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org> Link: https://lore.kernel.org/r/e942d2bd03afb8e8552bd2a5d84e18d17670d521.1615171203.git.skhan@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 47ccc8fc2c9c94558b27b6f9e2582df32d29e6e8 upstream.

Fix usbip_sockfd_store() to validate the passed in file descriptor is
a stream socket. If the file descriptor passed was a SOCK_DGRAM socket,
sock_recvmsg() can't detect end of stream.

Cc: stable@vger.kernel.org
Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/e942d2bd03afb8e8552bd2a5d84e18d17670d521.1615171203.git.skhan@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB: serial: cp210x: add some more GE USB IDs 2021-03-17T15:07:21+00:00 Sebastian Reichel sebastian.reichel@collabora.com 2021-02-23T16:44:18+00:00 b74d79db33f6fdfe709a1e088255be67df33508a commit 42213a0190b535093a604945db05a4225bf43885 upstream. GE CS1000 has some more custom USB IDs for CP2102N; add them to the driver to have working auto-probing. Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com> Cc: stable@vger.kernel.org Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 42213a0190b535093a604945db05a4225bf43885 upstream.

GE CS1000 has some more custom USB IDs for CP2102N; add them
to the driver to have working auto-probing.

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB: serial: cp210x: add ID for Acuity Brands nLight Air Adapter 2021-03-17T15:07:21+00:00 Karan Singhal karan.singhal@acuitybrands.com 2021-02-16T16:03:10+00:00 36b46eb0287f15d968b1498dd74713065920681e commit ca667a33207daeaf9c62b106815728718def60ec upstream. IDs of nLight Air Adapter, Acuity Brands, Inc.: vid: 10c4 pid: 88d8 Signed-off-by: Karan Singhal <karan.singhal@acuitybrands.com> Cc: stable@vger.kernel.org Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ca667a33207daeaf9c62b106815728718def60ec upstream.

IDs of nLight Air Adapter, Acuity Brands, Inc.:
vid: 10c4
pid: 88d8

Signed-off-by: Karan Singhal <karan.singhal@acuitybrands.com>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB: serial: ch341: add new Product ID 2021-03-17T15:07:21+00:00 Niv Sardi xaiki@evilgiggle.com 2021-03-01T20:16:12+00:00 cd9b4ad7897a883f0464d95915061e811393df4d commit 5563b3b6420362c8a1f468ca04afe6d5f0a8d0a3 upstream. Add PID for CH340 that's found on cheap programmers. The driver works flawlessly as soon as the new PID (0x9986) is added to it. These look like ANU232MI but ship with a ch341 inside. They have no special identifiers (mine only has the string "DB9D20130716" printed on the PCB and nothing identifiable on the packaging. The merchant i bought it from doesn't sell these anymore). the lsusb -v output is: Bus 001 Device 009: ID 9986:7523 Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 1.10 bDeviceClass 255 Vendor Specific Class bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 8 idVendor 0x9986 idProduct 0x7523 bcdDevice 2.54 iManufacturer 0 iProduct 0 iSerial 0 bNumConfigurations 1 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 0x0027 bNumInterfaces 1 bConfigurationValue 1 iConfiguration 0 bmAttributes 0x80 (Bus Powered) MaxPower 96mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 3 bInterfaceClass 255 Vendor Specific Class bInterfaceSubClass 1 bInterfaceProtocol 2 iInterface 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x82 EP 2 IN bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0020 1x 32 bytes bInterval 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x02 EP 2 OUT bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0020 1x 32 bytes bInterval 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x81 EP 1 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0008 1x 8 bytes bInterval 1 Signed-off-by: Niv Sardi <xaiki@evilgiggle.com> Cc: stable@vger.kernel.org Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 5563b3b6420362c8a1f468ca04afe6d5f0a8d0a3 upstream.

Add PID for CH340 that's found on cheap programmers.

The driver works flawlessly as soon as the new PID (0x9986) is added to it.
These look like ANU232MI but ship with a ch341 inside. They have no special
identifiers (mine only has the string "DB9D20130716" printed on the PCB and
nothing identifiable on the packaging. The merchant i bought it from
doesn't sell these anymore).

the lsusb -v output is:
Bus 001 Device 009: ID 9986:7523
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               1.10
  bDeviceClass          255 Vendor Specific Class
  bDeviceSubClass         0
  bDeviceProtocol         0
  bMaxPacketSize0         8
  idVendor           0x9986
  idProduct          0x7523
  bcdDevice            2.54
  iManufacturer           0
  iProduct                0
  iSerial                 0
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0027
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0
    bmAttributes         0x80
      (Bus Powered)
    MaxPower               96mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           3
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass      1
      bInterfaceProtocol      2
      iInterface              0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x82  EP 2 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0020  1x 32 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0020  1x 32 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0008  1x 8 bytes
        bInterval               1

Signed-off-by: Niv Sardi <xaiki@evilgiggle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB: serial: io_edgeport: fix memory leak in edge_startup 2021-03-17T15:07:21+00:00 Pavel Skripkin paskripkin@gmail.com 2021-03-01T23:01:52+00:00 8e9e62fb49a5fae2500924c2d4b6c80b65bf9cd0 commit cfdc67acc785e01a8719eeb7012709d245564701 upstream. sysbot found memory leak in edge_startup(). The problem was that when an error was received from the usb_submit_urb(), nothing was cleaned up. Reported-by: syzbot+59f777bdcbdd7eea5305@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> Fixes: 6e8cf7751f9f ("USB: add EPIC support to the io_edgeport driver") Cc: stable@vger.kernel.org # 2.6.21: c5c0c55598ce Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit cfdc67acc785e01a8719eeb7012709d245564701 upstream.

sysbot found memory leak in edge_startup().
The problem was that when an error was received from the usb_submit_urb(),
nothing was cleaned up.

Reported-by: syzbot+59f777bdcbdd7eea5305@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Fixes: 6e8cf7751f9f ("USB: add EPIC support to the io_edgeport driver")
Cc: stable@vger.kernel.org	# 2.6.21: c5c0c55598ce
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xhci: Improve detection of device initiated wake signal. 2021-03-17T15:07:21+00:00 Mathias Nyman mathias.nyman@linux.intel.com 2021-03-11T11:53:51+00:00 bc06115e1bfd393dd75adce5310e274cb10f5585 commit 253f588c70f66184b1f3a9bbb428b49bbda73e80 upstream. A xHC USB 3 port might miss the first wake signal from a USB 3 device if the port LFPS reveiver isn't enabled fast enough after xHC resume. xHC host will anyway be resumed by a PME# signal, but will go back to suspend if no port activity is seen. The device resends the U3 LFPS wake signal after a 100ms delay, but by then host is already suspended, starting all over from the beginning of this issue. USB 3 specs say U3 wake LFPS signal is sent for max 10ms, then device needs to delay 100ms before resending the wake. Don't suspend immediately if port activity isn't detected in resume. Instead add a retry. If there is no port activity then delay for 120ms, and re-check for port activity. Cc: <stable@vger.kernel.org> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210311115353.2137560-3-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 253f588c70f66184b1f3a9bbb428b49bbda73e80 upstream.

A xHC USB 3 port might miss the first wake signal from a USB 3 device
if the port LFPS reveiver isn't enabled fast enough after xHC resume.

xHC host will anyway be resumed by a PME# signal, but will go back to
suspend if no port activity is seen.
The device resends the U3 LFPS wake signal after a 100ms delay, but
by then host is already suspended, starting all over from the
beginning of this issue.

USB 3 specs say U3 wake LFPS signal is sent for max 10ms, then device
needs to delay 100ms before resending the wake.

Don't suspend immediately if port activity isn't detected in resume.
Instead add a retry. If there is no port activity then delay for 120ms,
and re-check for port activity.

Cc: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210311115353.2137560-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usb: renesas_usbhs: Clear PIPECFG for re-enabling pipe with other EPNUM 2021-03-17T15:07:21+00:00 Yoshihiro Shimoda yoshihiro.shimoda.uh@renesas.com 2021-03-08T01:55:38+00:00 670388a683ccd6414014683d62901336436dd5c2 commit b1d25e6ee57c2605845595b6c61340d734253eb3 upstream. According to the datasheet, this controller has a restriction which "set an endpoint number so that combinations of the DIR bit and the EPNUM bits do not overlap.". However, since the udc core driver is possible to assign a bulk pipe as an interrupt endpoint, an endpoint number may not match the pipe number. After that, when user rebinds another gadget driver, this driver broke the restriction because the driver didn't clear any configuration in usb_ep_disable(). Example: # modprobe g_ncm Then, EP3 = pipe 3, EP4 = pipe 4, EP5 = pipe 6 # rmmod g_ncm # modprobe g_hid Then, EP3 = pipe 6, EP4 = pipe 7. So, pipe 3 and pipe 6 are set as EP3. So, clear PIPECFG register in usbhs_pipe_free(). Fixes: dfb87b8bfe09 ("usb: renesas_usbhs: gadget: fix re-enabling pipe without re-connecting") Cc: stable <stable@vger.kernel.org> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Link: https://lore.kernel.org/r/1615168538-26101-1-git-send-email-yoshihiro.shimoda.uh@renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b1d25e6ee57c2605845595b6c61340d734253eb3 upstream.

According to the datasheet, this controller has a restriction
which "set an endpoint number so that combinations of the DIR bit and
the EPNUM bits do not overlap.". However, since the udc core driver is
possible to assign a bulk pipe as an interrupt endpoint, an endpoint
number may not match the pipe number. After that, when user rebinds
another gadget driver, this driver broke the restriction because
the driver didn't clear any configuration in usb_ep_disable().

Example:
 # modprobe g_ncm
 Then, EP3 = pipe 3, EP4 = pipe 4, EP5 = pipe 6
 # rmmod g_ncm
 # modprobe g_hid
 Then, EP3 = pipe 6, EP4 = pipe 7.
 So, pipe 3 and pipe 6 are set as EP3.

So, clear PIPECFG register in usbhs_pipe_free().

Fixes: dfb87b8bfe09 ("usb: renesas_usbhs: gadget: fix re-enabling pipe without re-connecting")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/1615168538-26101-1-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usb: gadget: f_uac2: always increase endpoint max_packet_size by one audio slot 2021-03-17T15:07:21+00:00 Ruslan Bilovol ruslan.bilovol@gmail.com 2021-03-01T11:49:31+00:00 02a4adc2c432c79ddb0b2ac551e28983fb50c18f commit 789ea77310f0200c84002884ffd628e2baf3ad8a upstream. As per UAC2 Audio Data Formats spec (2.3.1.1 USB Packets), if the sampling rate is a constant, the allowable variation of number of audio slots per virtual frame is +/- 1 audio slot. It means that endpoint should be able to accept/send +1 audio slot. Previous endpoint max_packet_size calculation code was adding sometimes +1 audio slot due to DIV_ROUND_UP behaviour which was rounding up to closest integer. However this doesn't work if the numbers are divisible. It had no any impact with Linux hosts which ignore this issue, but in case of more strict Windows it caused rejected enumeration Thus always add +1 audio slot to endpoint's max packet size Fixes: 913e4a90b6f9 ("usb: gadget: f_uac2: finalize wMaxPacketSize according to bandwidth") Cc: Peter Chen <peter.chen@freescale.com> Cc: <stable@vger.kernel.org> #v4.3+ Signed-off-by: Ruslan Bilovol <ruslan.bilovol@gmail.com> Link: https://lore.kernel.org/r/1614599375-8803-2-git-send-email-ruslan.bilovol@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 789ea77310f0200c84002884ffd628e2baf3ad8a upstream.

As per UAC2 Audio Data Formats spec (2.3.1.1 USB Packets),
if the sampling rate is a constant, the allowable variation
of number of audio slots per virtual frame is +/- 1 audio slot.

It means that endpoint should be able to accept/send +1 audio
slot.

Previous endpoint max_packet_size calculation code
was adding sometimes +1 audio slot due to DIV_ROUND_UP
behaviour which was rounding up to closest integer.
However this doesn't work if the numbers are divisible.

It had no any impact with Linux hosts which ignore
this issue, but in case of more strict Windows it
caused rejected enumeration

Thus always add +1 audio slot to endpoint's max packet size

Fixes: 913e4a90b6f9 ("usb: gadget: f_uac2: finalize wMaxPacketSize according to bandwidth")
Cc: Peter Chen <peter.chen@freescale.com>
Cc: <stable@vger.kernel.org> #v4.3+
Signed-off-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Link: https://lore.kernel.org/r/1614599375-8803-2-git-send-email-ruslan.bilovol@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>