Commit Graph

9 Commits

Author SHA1 Message Date
Suwan Kim
ea44d19076 usbip: Implement SG support to vhci-hcd and stub driver
There are bugs on vhci with usb 3.0 storage device. In USB, each SG
list entry buffer should be divisible by the bulk max packet size.
But with native SG support, this problem doesn't matter because the
SG buffer is treated as contiguous buffer. But without native SG
support, USB storage driver breaks SG list into several URBs and the
error occurs because of a buffer size of URB that cannot be divided
by the bulk max packet size. The error situation is as follows.

When USB Storage driver requests 31.5 KB data and has SG list which
has 3584 bytes buffer followed by 7 4096 bytes buffer for some
reason. USB Storage driver splits this SG list into several URBs
because VHCI doesn't support SG and sends them separately. So the
first URB buffer size is 3584 bytes. When receiving data from device,
USB 3.0 device sends data packet of 1024 bytes size because the max
packet size of BULK pipe is 1024 bytes. So device sends 4096 bytes.
But the first URB buffer has only 3584 bytes buffer size. So host
controller terminates the transfer even though there is more data to
receive. So, vhci needs to support SG transfer to prevent this error.

In this patch, vhci supports SG regardless of whether the server's
host controller supports SG or not, because stub driver splits SG
list into several URBs if the server's host controller doesn't
support SG.

To support SG, vhci sets URB_DMA_MAP_SG flag in urb->transfer_flags
if URB has SG list and this flag will tell stub driver to use SG
list. After receiving urb from stub driver, vhci clear URB_DMA_MAP_SG
flag to avoid unnecessary DMA unmapping in HCD.

vhci sends each SG list entry to stub driver. Then, stub driver sees
the total length of the buffer and allocates SG table and pages
according to the total buffer length calling sgl_alloc(). After stub
driver receives completed URB, it again sends each SG list entry to
vhci.

If the server's host controller doesn't support SG, stub driver
breaks a single SG request into several URBs and submits them to
the server's host controller. When all the split URBs are completed,
stub driver reassembles the URBs into a single return command and
sends it to vhci.

Moreover, in the situation where vhci supports SG, but stub driver
does not, or vice versa, usbip works normally. Because there is no
protocol modification, there is no problem in communication between
server and client even if the one has a kernel without SG support.

In the case of vhci supports SG and stub driver doesn't, because
vhci sends only the total length of the buffer to stub driver as
it did before the patch applied, stub driver only needs to allocate
the required length of buffers using only kmalloc() regardless of
whether vhci supports SG or not. But stub driver has to allocate
buffer with kmalloc() as much as the total length of SG buffer which
is quite huge when vhci sends SG request, so it has overhead in
buffer allocation in this situation.

If stub driver needs to send data buffer to vhci because of IN pipe,
stub driver also sends only total length of buffer as metadata and
then sends real data as vhci does. Then vhci receive data from stub
driver and store it to the corresponding buffer of SG list entry.

And for the case of stub driver supports SG and vhci doesn't, since
the USB storage driver checks that vhci doesn't support SG and sends
the request to stub driver by splitting the SG list into multiple
URBs, stub driver allocates a buffer for each URB with kmalloc() as
it did before this patch.

* Test environment

Test uses two difference machines and two different kernel version
to make mismatch situation between the client and the server where
vhci supports SG, but stub driver does not, or vice versa. All tests
are conducted in both full SG support that both vhci and stub support
SG and half SG support that is the mismatch situation. Test kernel
version is 5.3-rc6 with commit "usb: add a HCD_DMA flag instead of
guestimating DMA capabilities" to avoid unnecessary DMA mapping and
unmapping.

 - Test kernel version
    - 5.3-rc6 with SG support
    - 5.1.20-200.fc29.x86_64 without SG support

* SG support test

 - Test devices
    - Super-speed storage device - SanDisk Ultra USB 3.0
    - High-speed storage device - SMI corporation USB 2.0 flash drive

 - Test description

Test read and write operation of mass storage device that uses the
BULK transfer. In test, the client reads and writes files whose size
is over 1G and it works normally.

* Regression test

 - Test devices
    - Super-speed device - Logitech Brio webcam
    - High-speed device  - Logitech C920 HD Pro webcam
    - Full-speed device  - Logitech bluetooth mouse
                         - Britz BR-Orion speaker
    - Low-speed device   - Logitech wired mouse

 - Test description

Moving and click test for mouse. To test the webcam, use gnome-cheese.
To test the speaker, play music and video on the client. All works
normally.

* VUDC compatibility test

VUDC also works well with this patch. Tests are done with two USB
gadget created by CONFIGFS USB gadget. Both use the BULK pipe.

        1. Serial gadget
        2. Mass storage gadget

 - Serial gadget test

Serial gadget on the host sends and receives data using cat command
on the /dev/ttyGS<N>. The client uses minicom to communicate with
the serial gadget.

 - Mass storage gadget test

After connecting the gadget with vhci, use "dd" to test read and
write operation on the client side.

Read  - dd if=/dev/sd<N> iflag=direct of=/dev/null bs=1G count=1
Write - dd if=<my file path> iflag=direct of=/dev/sd<N> bs=1G count=1

Signed-off-by: Suwan Kim <suwan.kim027@gmail.com>
Acked-by: Shuah khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190828032741.12234-1-suwan.kim027@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-03 16:00:38 +02:00
Shuah Khan
248a220443 usbip: stub: stop printing kernel pointer addresses in messages
Remove and/or change debug, info. and error messages to not print
kernel pointer addresses.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-19 11:40:54 +01:00
Shuah Khan
be6123df1e usbip: fix stub_send_ret_submit() vulnerability to null transfer_buffer
stub_send_ret_submit() handles urb with a potential null transfer_buffer,
when it replays a packet with potential malicious data that could contain
a null buffer. Add a check for the condition when actual_length > 0 and
transfer_buffer is null.

Reported-by: Secunia Research <vuln@secunia.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-08 17:32:23 +01:00
Greg Kroah-Hartman
7f2b019c8d USB: usbip: Remove redundant license text
Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner.  So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text.  And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Valentina Manea <valentina.manea.m@gmail.com>
Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07 15:45:01 +01:00
Greg Kroah-Hartman
5fd54ace47 USB: add SPDX identifiers to all remaining files in drivers/usb/
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/usb/ and include/linux/usb* files with the correct
SPDX license identifier based on the license text in the file itself.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04 11:48:02 +01:00
Michael Grzeschik
b3b51417d0 usb: usbip: set buffer pointers to NULL after free
The usbip stack dynamically allocates the transfer_buffer and
setup_packet of each urb that got generated by the tcp to usb stub code.
As these pointers are always used only once we will set them to NULL
after use. This is done likewise to the free_urb code in vudc_dev.c.
This patch fixes double kfree situations where the usbip remote side
added the URB_FREE_BUFFER.

Cc: stable@vger.kernel.org
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-13 10:48:24 +02:00
Nobuo Iwata
6dc38da4a5 usbip: safe completion against unbind operation
This patch adds a code fragment to ignore completing URBs in closing
connection.

Regarding this patch, 2 execution contexts are related.

1) stub_tx.c: stub_complete() which is called from USB core
1-1) add to unlink list and free URB or
1-2) move to tx list

2) stub_dev.c: stub_shutdown_connection() which is invoked by unbind
operation through sysfs.
2-1) stop TX/RX threads
2-2) close TCP connection and set ud.tcp_socket to NULL
2-3) cleanup pending URBs by stub_device_cleanup_urbs(sdev)
2-4) free unlink list (no lock)

In the race condition, URBs which will be cleared in 2-3) may be
handled in 1).
In case 1-1), it will not be transferred bcause tx threads are stooped
in 2-1).
In case 1-2), may be freed in 2-4).

With this patch, after 2-2), completing URBs in 1) will not be handled
and cleared in 2-3).

The kernel log with this patch is as below.

kernel: usbip_core: usbip_kernel_unlink:792: shutting down tcp_socket
ef61d980
kernel: usbip-host 1-3: free sdev f5df6180
kernel: usbip-host 1-3: free urb f5df6700
kernel: usbip-host 1-3: Enter
kernel: usbip_core: usbip_stop_eh:132: usbip_eh waiting completion 5
kernel: usbip_host: stub_complete:71: complete! status 0
kernel: usbip_host: stub_complete:102: ignore urb for closed connection
e725fc00 (*)
kernel: usbip_host: stub_complete:71: complete! status -2
kernel: usbip-host 1-3: stopped by a call to usb_kill_urb() because of
cleaning up a virtual connection
kernel: usbip-host 1-3: free urb e725fc00 (**)
kernel: usbip-host 1-3: free urb e725e000
kernel: usbip_host: stub_complete:71: complete! status -2
kernel: usbip-host 1-3: stopped by a call to usb_kill_urb() because of
cleaning up a virtual connection
kernel: usbip-host 1-3: free urb e725f800
kernel: usbip_host: stub_complete:71: complete! status -2
kernel: usbip-host 1-3: stopped by a call to usb_kill_urb() because of
cleaning up a virtual connection
kernel: usbip-host 1-3: free urb e725e800
kernel: usbip_host: stub_complete:71: complete! status -2
kernel: usbip-host 1-3: stopped by a call to usb_kill_urb() because of
cleaning up a virtual connection
kernel: usbip-host 1-3: device reset
kernel: usbip-host 1-3: lock for reset
kernel: usbip_host: store_match_busid:178: del busid 1-3
kernel: uvcvideo: Found UVC 1.00 device Venus USB2.0 Camera (056e:700a)
kernel: input: Venus USB2.0 Camera as
/devices/pci0000:00/0000:00:1a.7/usb1/1-3/1-3:1.0/input/input22

(*) skipped with this patch in completion
(**) released in 2-3

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-28 12:28:08 -07:00
Alexander Popov
8c7003a3b4 usbip: fix NULL pointer dereference on errors
Fix NULL pointer dereference and obsolete comments forgotten when
usbip server was converted from an interface driver to a device driver.

Signed-off-by: Alexander Popov <alpopov@ptsecurity.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-28 12:28:08 -07:00
Valentina Manea
96c2737716 usbip: move usbip kernel code out of staging
At this point, USB/IP kernel code is fully functional
and can be moved out of staging.

Signed-off-by: Valentina Manea <valentina.manea.m@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-25 10:40:06 -07:00