From: Nicholas Kazlauskas nicholas.kazlauskas@amd.com
[ Upstream commit 44a09e3d95bd2b7b0c224100f78f335859c4e193 ]
[Why] If the BIOS table is invalid or corrupt then get_i2c_info can fail and we dereference a NULL pointer.
[How] Check that ddc_pin is not NULL before using it and log an error if it is because this is unexpected.
Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Nicholas Kazlauskas nicholas.kazlauskas@amd.com Reviewed-by: Eric Yang eric.yang2@amd.com Acked-by: Anson Jacob anson.jacob@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/display/dc/core/dc_link.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c index e1e5d81a5e43..21c7b642a8b4 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c @@ -1454,6 +1454,11 @@ static bool dc_link_construct(struct dc_link *link, goto ddc_create_fail; }
+ if (!link->ddc->ddc_pin) { + DC_ERROR("Failed to get I2C info for connector!\n"); + goto ddc_create_fail; + } + link->ddc_hw_inst = dal_ddc_get_line(dal_ddc_service_get_ddc_pin(link->ddc));