[PATCH 11/16] drm/amd/display: Handle dml allocation failure to avoid crash

[Hamza Mahfooz]

From: Ryan Seto <ryanseto at amd.com>

[Why]
In the case where a dml allocation fails for any reason, the
current state's dml contexts would no longer be valid. Then
subsequent calls dc_state_copy_internal would shallow copy
invalid memory and if the new state was released, a double
free would occur.

[How]
Reset dml pointers in new_state to NULL and avoid invalid
pointer

Cc: stable at vger.kernel.org
Reviewed-by: Dillon Varone <dillon.varone at amd.com>
Signed-off-by: Ryan Seto <ryanseto at amd.com>
Signed-off-by: Hamza Mahfooz <hamza.mahfooz at amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc_state.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_state.c b/drivers/gpu/drm/amd/display/dc/core/dc_state.c
index 2597e3fd562b..e006f816ff2f 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_state.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_state.c
@@ -265,6 +265,9 @@ struct dc_state *dc_state_create_copy(struct dc_state *src_state)
 	dc_state_copy_internal(new_state, src_state);
 
 #ifdef CONFIG_DRM_AMD_DC_FP
+	new_state->bw_ctx.dml2 = NULL;
+	new_state->bw_ctx.dml2_dc_power_source = NULL;
+
 	if (src_state->bw_ctx.dml2 &&
 			!dml2_create_copy(&new_state->bw_ctx.dml2, src_state->bw_ctx.dml2)) {
 		dc_state_release(new_state);
-- 
2.46.1