Imre DeakandGreg Kroah-Hartman 9735d40f5f drm/dp_mst: Ensure mst_primary pointer is valid in drm_dp_mst_handle_up_req() ...

[ Upstream commit e54b00086f ]

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.

Cc: Lyude Paul <lyude@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com> (v1)
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241204132007.3132494-1-imre.deak@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

2025-01-02 10:32:06 +01:00

..

drm_display_helper_mod.c

…

drm_dp_aux_bus.c

…

drm_dp_aux_dev.c

…

drm_dp_cec.c

…

drm_dp_dual_mode_helper.c

drm/display: Fix building with GCC 15

2024-12-14 20:00:02 +01:00

drm_dp_helper_internal.h

…

drm_dp_helper.c

…

drm_dp_mst_topology_internal.h

…

drm_dp_mst_topology.c

drm/dp_mst: Ensure mst_primary pointer is valid in drm_dp_mst_handle_up_req()

2025-01-02 10:32:06 +01:00

drm_dsc_helper.c

…

drm_hdcp_helper.c

…

drm_hdmi_helper.c

…

drm_scdc_helper.c

…

Kconfig

…

Makefile

…