CVE-2024-35247: fpga: region: add owner module and take its refcount

Description

In the Linux kernel, the following vulnerability has been resolved:

fpga: region: add owner module and take its refcount

The current implementation of the fpga region assumes that the low-level
module registers a driver for the parent device and uses its owner pointer
to take the module's refcount. This approach is problematic since it can
lead to a null pointer dereference while attempting to get the region
during programming if the parent device does not have a driver.

To address this problem, add a module owner pointer to the fpga_region
struct and use it to take the module's refcount. Modify the functions for
registering a region to take an additional owner module parameter and
rename them to avoid conflicts. Use the old function names for helper
macros that automatically set the module that registers the region as the
owner. This ensures compatibility with existing low-level control modules
and reduces the chances of registering a region without setting the owner.

Also, update the documentation to keep it consistent with the new interface
for registering an fpga region.

Classification

CVE ID: CVE-2024-35247

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.04% (probability of being exploited)

EPSS Percentile: 5.08% (scored less or equal to compared to others)

EPSS Date: 2025-02-04 (when was this score calculated)

References

https://git.kernel.org/stable/c/26e6e25d742e29885cf44274fcf6b744366c4702
https://git.kernel.org/stable/c/9b4eee8572dcf82b2ed17d9a328c7fb87df2f0e8
https://git.kernel.org/stable/c/75a001914a8d2ccdcbe4b8cc7e94ac71d0e66093
https://git.kernel.org/stable/c/4d7d12b643c00e7eea51b49a60a2ead182633ec8
https://git.kernel.org/stable/c/2279c09c36165ccded4d506d11a7714e13b56019
https://git.kernel.org/stable/c/b7c0e1ecee403a43abc89eb3e75672b01ff2ece9

Timeline