7bdd969597
In pp_release(), there is an if statement on line 730 to check whether
pp->pdev is NULL:
else if ((pp->flags & PP_CLAIMED) && pp->pdev && ...)
When pp->pdev is NULL, it is used on line 743:
info = &pp->pdev->port->ieee1284;
and on line 748:
parport_release(pp->pdev);
Thus, a possible null-pointer dereference may occur.
To fix this bug, pp->pdev is checked on line 740.
This bug is found by a static analysis tool STCheck written by us.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Link: https://lore.kernel.org/r/20190724090426.1401-1-baijiaju1990@gmail.com
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.