| 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-2024-57876: drm/dp_mst: Fix resetting msg rx state after topology removal |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| drm/dp_mst: Fix resetting msg rx state after topology removal |
| |
| If the MST topology is removed during the reception of an MST down reply |
| or MST up request sideband message, the |
| drm_dp_mst_topology_mgr::up_req_recv/down_rep_recv states could be reset |
| from one thread via drm_dp_mst_topology_mgr_set_mst(false), racing with |
| the reading/parsing of the message from another thread via |
| drm_dp_mst_handle_down_rep() or drm_dp_mst_handle_up_req(). The race is |
| possible since the reader/parser doesn't hold any lock while accessing |
| the reception state. This in turn can lead to a memory corruption in the |
| reader/parser as described by commit bd2fccac61b4 ("drm/dp_mst: Fix MST |
| sideband message body length check"). |
| |
| Fix the above by resetting the message reception state if needed before |
| reading/parsing a message. Another solution would be to hold the |
| drm_dp_mst_topology_mgr::lock for the whole duration of the message |
| reception/parsing in drm_dp_mst_handle_down_rep() and |
| drm_dp_mst_handle_up_req(), however this would require a bigger change. |
| Since the fix is also needed for stable, opting for the simpler solution |
| in this patch. |
| |
| The Linux kernel CVE team has assigned CVE-2024-57876 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.1.18 with commit b30fcedeba643ca16eaa6212c1245598b7cd830d and fixed in 6.1.120 with commit 94b33b2d7640e807869451384eb88321dd0ffbd4 |
| Issue introduced in 6.3 with commit 1d082618bbf3b6755b8cc68c0a8122af2842d593 and fixed in 6.6.66 with commit d834d20d2e86c52ed5cab41763fa61e6071680ef |
| Issue introduced in 6.3 with commit 1d082618bbf3b6755b8cc68c0a8122af2842d593 and fixed in 6.12.5 with commit be826b4451fd187a7c0b04be4f8243d5df6e0450 |
| Issue introduced in 6.3 with commit 1d082618bbf3b6755b8cc68c0a8122af2842d593 and fixed in 6.13 with commit a6fa67d26de385c3c7a23c1e109a0e23bfda4ec7 |
| Issue introduced in 5.10.173 with commit ee4a4282d78d96e07e714c28ca54679713fa2157 |
| Issue introduced in 5.15.100 with commit db35e49413a4d03ea0c003598803e49956f59324 |
| Issue introduced in 6.2.5 with commit a579ed4613b5a64074963988ad481e43cf3b917b |
| |
| 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-2024-57876 |
| 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/display/drm_dp_mst_topology.c |
| include/drm/display/drm_dp_mst_helper.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/94b33b2d7640e807869451384eb88321dd0ffbd4 |
| https://git.kernel.org/stable/c/d834d20d2e86c52ed5cab41763fa61e6071680ef |
| https://git.kernel.org/stable/c/be826b4451fd187a7c0b04be4f8243d5df6e0450 |
| https://git.kernel.org/stable/c/a6fa67d26de385c3c7a23c1e109a0e23bfda4ec7 |
