[PATCH 5.10 637/717] drm/amd/display: Fix memory leaks in S3 resume

Greg Kroah-Hartman
2020-12-28T14:40:01Z

From: Stylon Wang <stylon.wang@amd.com>

commit a135a1b4c4db1f3b8cbed9676a40ede39feb3362 upstream.

EDID parsing in S3 resume pushes new display modes
to probed_modes list but doesn't consolidate to actual
mode list. This creates a race condition when
amdgpu_dm_connector_ddc_get_modes() re-initializes the
list head without walking the list and results in memory leak.

Bug: https://bugzilla.kernel.org/show_bug.cgi?id=209987
Acked-by: Harry Wentland <harry.wentland@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Stylon Wang <stylon.wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2278,7 +2278,8 @@ void amdgpu_dm_update_connector_after_de

drm_connector_update_edid_property(connector,
aconnector->edid);
- drm_add_edid_modes(connector, aconnector->edid);
+ aconnector->num_modes = drm_add_edid_modes(connector, aconnector->edid);
+ drm_connector_list_update(connector);

if (aconnector->dc_link->aux_mode)
drm_dp_cec_set_edid(&aconnector->dm_dp_aux.aux,