The work item can operate on

1. stale memory left over from the last transfer
the actual length of the data transfered needs to be checked
2. memory already freed
the error handling in appledisplay_probe() needs
to cancel the work in that case

Reported-and-tested-by: syzbot+495dab1f175edc9c2f13@syzkaller.appspotmail.com
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191106124902.7765-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

We want the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The spinlock was inside the urb completion function which is only
called once per display and is then resubmitted from this function.
There was no other place where this lock was used.

Signed-off-by: Alexander Theissen <alex.theissen@me.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver does allocate a DMA address with usb_alloc_coherent but did
not set the appropriate flag to signal that transfer_dma is set to a
valid value.

Signed-off-by: Alexander Theissen <alex.theissen@me.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Add another Apple Cinema Display to the list of supported displays.

Signed-off-by: Alexander Theissen <alex.theissen@me.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Add another Apple Cinema Display to the list of supported displays

Signed-off-by: Mattias Jacobsson <2pi@mok.nu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Upon success the update_status handler returns a positive number
corresponding to the number of bytes transferred by usb_control_msg.
However the return code of the update_status handler should indicate if
an error occurred(negative) or how many bytes of the user's input to sysfs
that was consumed. Return code zero indicates all bytes were consumed.

The bug can for example result in the update_status handler being called
twice, the second time with only the "unconsumed" part of the user's input
to sysfs. Effectively setting an incorrect brightness.

Change the update_status handler to return zero for all successful
transactions and forward usb_control_msg's error code upon failure.

Signed-off-by: Mattias Jacobsson <2pi@mok.nu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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: Keith Packard <keithp@keithp.com>
Cc: Juergen Stuber <starblue@users.sourceforge.net>
Cc: Cesar Miquel <miquel@df.uba.ar>
Cc: Richard Leitner <richard.leitner@skidata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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>