[PATCH AUTOSEL 6.14 09/44] drm/amd/display: Guard Possible Null Pointer Dereference

[Sasha Levin]

From: Sung Lee <Sung.Lee@xxxxxxx>

[ Upstream commit c87d202692de34ee71d1fd4679a549a29095658a ]

[WHY]
In some situations, dc->res_pool may be null.

[HOW]
Check if pointer is null before dereference.

Reviewed-by: Joshua Aberback <joshua.aberback@xxxxxxx>
Signed-off-by: Sung Lee <Sung.Lee@xxxxxxx>
Signed-off-by: Zaeem Mohamed <zaeem.mohamed@xxxxxxx>
Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/amd/display/dc/core/dc.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
index f84e795e35f58..4683c7ef4507f 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -5549,9 +5549,11 @@ void dc_allow_idle_optimizations_internal(struct dc *dc, bool allow, char const
 	if (dc->clk_mgr != NULL && dc->clk_mgr->funcs->get_hard_min_memclk)
 		idle_dramclk_khz = dc->clk_mgr->funcs->get_hard_min_memclk(dc->clk_mgr);
 
-	for (i = 0; i < dc->res_pool->pipe_count; i++) {
-		pipe = &context->res_ctx.pipe_ctx[i];
-		subvp_pipe_type[i] = dc_state_get_pipe_subvp_type(context, pipe);
+	if (dc->res_pool && context) {
+		for (i = 0; i < dc->res_pool->pipe_count; i++) {
+			pipe = &context->res_ctx.pipe_ctx[i];
+			subvp_pipe_type[i] = dc_state_get_pipe_subvp_type(context, pipe);
+		}
 	}
 
 	DC_LOG_DC("%s: allow_idle=%d\n HardMinUClk_Khz=%d HardMinDramclk_Khz=%d\n Pipe_0=%d Pipe_1=%d Pipe_2=%d Pipe_3=%d Pipe_4=%d Pipe_5=%d (caller=%s)\n",
-- 
2.39.5