| 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-2024-46870: drm/amd/display: Disable DMCUB timeout for DCN35 |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| drm/amd/display: Disable DMCUB timeout for DCN35 |
| |
| [Why] |
| DMCUB can intermittently take longer than expected to process commands. |
| |
| Old ASIC policy was to continue while logging a diagnostic error - which |
| works fine for ASIC without IPS, but with IPS this could lead to a race |
| condition where we attempt to access DCN state while it's inaccessible, |
| leading to a system hang when the NIU port is not disabled or register |
| accesses that timeout and the display configuration in an undefined |
| state. |
| |
| [How] |
| We need to investigate why these accesses take longer than expected, but |
| for now we should disable the timeout on DCN35 to avoid this race |
| condition. Since the waits happen only at lower interrupt levels the |
| risk of taking too long at higher IRQ and causing a system watchdog |
| timeout are minimal. |
| |
| The Linux kernel CVE team has assigned CVE-2024-46870 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 6.10.9 with commit 31c254c9cd4b122a10db297124f867107a696d83 |
| Fixed in 6.11 with commit 7c70e60fbf4bff1123f0e8d5cb1ae71df6164d7f |
| |
| 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-2024-46870 |
| 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/amd/display/dc/resource/dcn35/dcn35_resource.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/31c254c9cd4b122a10db297124f867107a696d83 |
| https://git.kernel.org/stable/c/7c70e60fbf4bff1123f0e8d5cb1ae71df6164d7f |
