4210c35fe8
[ Upstream commit 977d2e7c63c3d04d07ba340b39987742e3241554 ]
In nonstatic_find_mem_region(), pcmcia_make_resource() is assigned to
res and used in pci_bus_alloc_resource(). There a dereference of res
in pci_bus_alloc_resource(), which could lead to a NULL pointer
dereference on failure of pcmcia_make_resource().
Fix this bug by adding a check of res.
This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.
Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.
Builds with CONFIG_PCCARD_NONSTATIC=y show no new warnings,
and our static analyzer no longer warns about this code.
Fixes: 49b1153adfe1 ("pcmcia: move all pcmcia_resource_ops providers into one module")
Signed-off-by: Zhou Qingyang <zhou1615@umn.edu>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Sasha Levin <sashal@kernel.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.