| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-37021: fpga: manager: add owner module and take its refcount |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| fpga: manager: add owner module and take its refcount |
| |
| The current implementation of the fpga manager 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 manager if |
| the parent device does not have a driver. |
| |
| To address this problem, add a module owner pointer to the fpga_manager |
| struct and use it to take the module's refcount. Modify the functions for |
| registering the manager 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 manager as the |
| owner. This ensures compatibility with existing low-level control modules |
| and reduces the chances of registering a manager without setting the owner. |
| |
| Also, update the documentation to keep it consistent with the new interface |
| for registering an fpga manager. |
| |
| Other changes: opportunistically move put_device() from __fpga_mgr_get() to |
| fpga_mgr_get() and of_fpga_mgr_get() to improve code clarity since the |
| manager device is taken in these functions. |
| |
| The Linux kernel CVE team has assigned CVE-2024-37021 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.4 with commit 654ba4cc0f3ed7c0f08bfb39f66059d8c42943ee and fixed in 6.1.120 with commit 304f8032d601d4f9322ca841cd0b573bd1beb158 |
| Issue introduced in 4.4 with commit 654ba4cc0f3ed7c0f08bfb39f66059d8c42943ee and fixed in 6.6.33 with commit 2da62a139a6221a345db4eb9f4f1c4b0937c89ad |
| Issue introduced in 4.4 with commit 654ba4cc0f3ed7c0f08bfb39f66059d8c42943ee and fixed in 6.9.4 with commit 62ac496a01c9337a11362cea427038ba621ca9eb |
| Issue introduced in 4.4 with commit 654ba4cc0f3ed7c0f08bfb39f66059d8c42943ee and fixed in 6.10 with commit 4d4d2d4346857bf778fafaa97d6f76bb1663e3c9 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2024-37021 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| Documentation/driver-api/fpga/fpga-mgr.rst |
| drivers/fpga/fpga-mgr.c |
| include/linux/fpga/fpga-mgr.h |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/304f8032d601d4f9322ca841cd0b573bd1beb158 |
| https://git.kernel.org/stable/c/2da62a139a6221a345db4eb9f4f1c4b0937c89ad |
| https://git.kernel.org/stable/c/62ac496a01c9337a11362cea427038ba621ca9eb |
| https://git.kernel.org/stable/c/4d4d2d4346857bf778fafaa97d6f76bb1663e3c9 |
