cf8f169670
The function virtqueue_add_split() DMA-maps the scatterlist buffers. In case a mapping error occurs the already mapped buffers must be unmapped. This happens by jumping to the 'unmap_release' label. In case of indirect descriptors the release is wrong and may leak kernel memory. Because the implementation assumes that the head descriptor is already mapped it starts iterating over the descriptor list starting from the head descriptor. However for indirect descriptors the head descriptor is never mapped in case of an error. The fix is to initialize the start index with zero in case of indirect descriptors and use the 'desc' pointer directly for iterating over the descriptor chain. Signed-off-by: Matthias Lange <matthias.lange@kernkonzept.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
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
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.