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authorQingqing Zhuo <qingqing.zhuo@amd.com>2020-12-09 18:04:04 -0500
committerAlex Deucher <alexander.deucher@amd.com>2021-01-14 00:17:16 -0500
commit73644143b31cb95866c19e0d94be9e3127ec3a6b (patch)
tree8234bf2a7ac088122331ced80d448c913c7cf332 /drivers/gpu/drm/amd
parentf14a5c34d143f6627f0be70c0de1d962f3a6ff1c (diff)
downloadlinux-73644143b31cb95866c19e0d94be9e3127ec3a6b.tar.bz2
drm/amd/display: NULL pointer hang
[Why] In dc_link_dp_set_test_pattern, we assume all pipes have a stream, which can cause null pointer dereference. [How] Add a null pointer check before accessing stream. Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Qingqing Zhuo <qingqing.zhuo@amd.com> Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com> Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Diffstat (limited to 'drivers/gpu/drm/amd')
-rw-r--r--drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
index 2fc12239b22c..1bd1a0935290 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
@@ -3992,7 +3992,7 @@ bool dc_link_dp_set_test_pattern(
unsigned int cust_pattern_size)
{
struct pipe_ctx *pipes = link->dc->current_state->res_ctx.pipe_ctx;
- struct pipe_ctx *pipe_ctx = &pipes[0];
+ struct pipe_ctx *pipe_ctx = NULL;
unsigned int lane;
unsigned int i;
unsigned char link_qual_pattern[LANE_COUNT_DP_MAX] = {0};
@@ -4002,12 +4002,18 @@ bool dc_link_dp_set_test_pattern(
memset(&training_pattern, 0, sizeof(training_pattern));
for (i = 0; i < MAX_PIPES; i++) {
+ if (pipes[i].stream == NULL)
+ continue;
+
if (pipes[i].stream->link == link && !pipes[i].top_pipe && !pipes[i].prev_odm_pipe) {
pipe_ctx = &pipes[i];
break;
}
}
+ if (pipe_ctx == NULL)
+ return false;
+
/* Reset CRTC Test Pattern if it is currently running and request is VideoMode */
if (link->test_pattern_enabled && test_pattern ==
DP_TEST_PATTERN_VIDEO_MODE) {