| From bippy-1.1.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2022-49896: cxl/pmem: Fix cxl_pmem_region and cxl_memdev leak |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| cxl/pmem: Fix cxl_pmem_region and cxl_memdev leak |
| |
| When a cxl_nvdimm object goes through a ->remove() event (device |
| physically removed, nvdimm-bridge disabled, or nvdimm device disabled), |
| then any associated regions must also be disabled. As highlighted by the |
| cxl-create-region.sh test [1], a single device may host multiple |
| regions, but the driver was only tracking one region at a time. This |
| leads to a situation where only the last enabled region per nvdimm |
| device is cleaned up properly. Other regions are leaked, and this also |
| causes cxl_memdev reference leaks. |
| |
| Fix the tracking by allowing cxl_nvdimm objects to track multiple region |
| associations. |
| |
| The Linux kernel CVE team has assigned CVE-2022-49896 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.0 with commit 04ad63f086d1a9649b8b082748cbc7a570ade461 and fixed in 6.0.8 with commit f43b6bfdbab78606735ba81185cf0602b81e40b6 |
| Issue introduced in 6.0 with commit 04ad63f086d1a9649b8b082748cbc7a570ade461 and fixed in 6.1 with commit 4d07ae22e79ebc2d7528bbc69daa53b86981cb3a |
| |
| 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-2022-49896 |
| 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: |
| drivers/cxl/core/pmem.c |
| drivers/cxl/cxl.h |
| drivers/cxl/pmem.c |
| |
| |
| 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/f43b6bfdbab78606735ba81185cf0602b81e40b6 |
| https://git.kernel.org/stable/c/4d07ae22e79ebc2d7528bbc69daa53b86981cb3a |
