From: Alex Hung alex.hung@amd.com

commit 8aa2864044b9d13e95fe224f32e808afbf79ecdf ("drm/amd/display: Check link_index before accessing dc->links[]")

[WHY & HOW] dc->links[] has max size of MAX_LINKS and NULL is return when trying to access with out-of-bound index.

This fixes 3 OVERRUN and 1 RESOURCE_LEAK issues reported by Coverity.

Fixes: CVE-2024-46813 Reviewed-by: Harry Wentland harry.wentland@amd.com Acked-by: Tom Chung chiahsuan.chung@amd.com Signed-off-by: Alex Hung alex.hung@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com (cherry picked from commit 8aa2864044b9d13e95fe224f32e808afbf79ecdf) Signed-off-by: Shubham Pushpkar spushpka@cisco.com --- drivers/gpu/drm/amd/display/dc/core/dc_link_exports.c | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_exports.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_exports.c index f365773d5714..b5639e88c581 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_exports.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_exports.c @@ -37,6 +37,9 @@ #include "dce/dce_i2c.h" struct dc_link *dc_get_link_at_index(struct dc *dc, uint32_t link_index) { + if (link_index >= MAX_LINKS) + return NULL; + return dc->links[link_index]; }