On 22.02.2023 15:44, Krzysztof Kozlowski wrote:
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:
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.
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@linaro.org
Fixes: 02efb49aa805 ("soundwire: qcom: add support for SoundWire controller")
Reviewed-by: Konrad Dybcio konrad.dybcio@linaro.org
Konrad
drivers/soundwire/qcom.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c index 79bebcecde6d..c296e0bf897b 100644 --- a/drivers/soundwire/qcom.c +++ b/drivers/soundwire/qcom.c @@ -1218,6 +1218,9 @@ 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);