d39b5bad86
A second regression was found in the immediate data transfer (IDT)
support which was added to 5.2 kernel
IDT is used to transfer small amounts of data (up to 8 bytes) in the
field normally used for data dma address, thus avoiding dma mapping.
If the data was not already dma mapped, then IDT support assumed data was
in urb->transfer_buffer, and did not take into accound that even
small amounts of data (8 bytes) can be in a scatterlist instead.
This caused a NULL pointer dereference when sg_dma_len() was used
with non-dma mapped data.
Solve this by not using IDT if scatter gather buffer list is used.
Fixes: 33e39350ebd2 ("usb: xhci: add Immediate Data Transfer support")
Cc: <stable@vger.kernel.org> # v5.2
Reported-by: Maik Stohn <maik.stohn@seal-one.com>
Tested-by: Maik Stohn <maik.stohn@seal-one.com>
CC: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/1564044861-1445-1-git-send-email-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
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In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
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