| 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-2023-53095: drm/ttm: Fix a NULL pointer dereference |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| drm/ttm: Fix a NULL pointer dereference |
| |
| The LRU mechanism may look up a resource in the process of being removed |
| from an object. The locking rules here are a bit unclear but it looks |
| currently like res->bo assignment is protected by the LRU lock, whereas |
| bo->resource is protected by the object lock, while *clearing* of |
| bo->resource is also protected by the LRU lock. This means that if |
| we check that bo->resource points to the LRU resource under the LRU |
| lock we should be safe. |
| So perform that check before deciding to swap out a bo. That avoids |
| dereferencing a NULL bo->resource in ttm_bo_swapout(). |
| |
| The Linux kernel CVE team has assigned CVE-2023-53095 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.19 with commit 6a9b028994025f5033f10d1da30b29dfdc713384 and fixed in 6.1.21 with commit 9ba1720f6c4a0f13c3f3cb5c28132ee75555d04f |
| Issue introduced in 5.19 with commit 6a9b028994025f5033f10d1da30b29dfdc713384 and fixed in 6.2.8 with commit 9d9b1f9f7a72d83ebf173534e76b246349f32374 |
| Issue introduced in 5.19 with commit 6a9b028994025f5033f10d1da30b29dfdc713384 and fixed in 6.3 with commit 9a9a8fe26751334b7739193a94eba741073b8a55 |
| |
| 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-2023-53095 |
| 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/gpu/drm/ttm/ttm_device.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/9ba1720f6c4a0f13c3f3cb5c28132ee75555d04f |
| https://git.kernel.org/stable/c/9d9b1f9f7a72d83ebf173534e76b246349f32374 |
| https://git.kernel.org/stable/c/9a9a8fe26751334b7739193a94eba741073b8a55 |
