Severity
Details
- CVSS score
- 7.8
- CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
drm/dp_mst: Ensure mst_primary pointer is valid in drm_dp_mst_handle_up_req()
While receiving an MST up request message from one thread in drm_dp_mst_handle_up_req(), the MST topology could be removed from another thread via drm_dp_mst_topology_mgr_set_mst(false), freeing mst_primary and setting drm_dp_mst_topology_mgr::mst_primary to NULL. This could lead to a NULL deref/use-after-free of mst_primary in drm_dp_mst_handle_up_req().
Avoid the above by holding a reference for mst_primary in drm_dp_mst_handle_up_req() while it’s used.
v2: Fix kfreeing the request if getting an mst_primary reference fails.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 6 ELS , CloudLinux 7 ELS , Oracle Linux 6 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS
- Affected packages:
- kernel @ 2.6.32 (+15 more)
In the Linux kernel, the following vulnerability has been resolved:
drm/dp_mst: Ensure mst_primary pointer is valid in drm_dp_mst_handle_up_req()
While receiving an MST up request message from one thread in drm_dp_mst_handle_up_req(), the MST topology could be removed from another thread via drm_dp_mst_topology_mgr_set_mst(false), freeing mst_primary and setting drm_dp_mst_topology_mgr::mst_primary to NULL. This could lead to a NULL deref/use-after-free of mst_primary in drm_dp_mst_handle_up_req().
Avoid the above by holding a reference for mst_primary in drm_dp_mst_handle_up_req() while it’s used.
v2: Fix kfreeing the request if getting an mst_primary reference fails.