From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> [ Upstream commit 2367e0ecb498764e95cfda691ff0828f7d25f9a4 ] There are two issues related to the number of ports coming from Devicetree when exceeding in total QCOM_SDW_MAX_PORTS. Both lead to incorrect memory accesses: 1. With DTS having too big value of input or output ports, the driver, when copying port parameters from local/stack arrays into 'pconfig' array in 'struct qcom_swrm_ctrl', will iterate over their sizes. 2. If DTS also has too many parameters for these ports (e.g. qcom,ports-sinterval-low), the driver will overflow buffers on the stack when reading these properties from DTS. Add a sanity check so incorrect DTS will not cause kernel memory corruption. Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx> Reviewed-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx> Link: https://lore.kernel.org/r/20230222144412.237832-2-krzysztof.kozlowski@xxxxxxxxxx Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/soundwire/qcom.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c index cee2b22231410..c535da166ca1d 100644 --- a/drivers/soundwire/qcom.c +++ b/drivers/soundwire/qcom.c @@ -1209,6 +1209,9 @@ static int qcom_swrm_get_port_config(struct qcom_swrm_ctrl *ctrl) ctrl->num_dout_ports = val; nports = ctrl->num_dout_ports + ctrl->num_din_ports; + if (nports > QCOM_SDW_MAX_PORTS) + return -EINVAL; + /* Valid port numbers are from 1-14, so mask out port 0 explicitly */ set_bit(0, &ctrl->dout_port_mask); set_bit(0, &ctrl->din_port_mask); -- 2.39.2
