51f6302f81
commit 3ed21c1451a14d139e1ceb18f2fa70865ce3195a upstream.
In this function "c->off" is a u32 and "size" is a long. On 64bit systems
if "c->off" is greater than "size" then "size - c->off" is a negative and
we always return -E2BIG. But on 32bit systems the subtraction is type
promoted to a high positive u32 value and basically any "c->len" is
accepted.
Fixes: 4c8cf31885f6 ("vhost: introduce vDPA-based backend")
Reported-by: Xie Yongji <xieyongji@bytedance.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20211208103337.GA4047@kili
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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.